View Full Version : Busa Datsun

09-28-2013, 09:43 PM
I purchased a wrecked Hayabusa last January and was looking around for a Austin Mini Cooper to put it into. Well they are hard to come by and well just too expensive to purchase and ship. I came across this 1967.5 Datsun roadster and well the wheels started turning.
I called Yoshi and picked his brain for a minute just before I bought the car, but now I'm wanting some of your opinions on what route I should go.

Option #1,(discussed with Yoshi) Position the engine transvers in the car, hook up the output shaft to a drive shaft into Yoshi's reverser and then to the Rear axle. What I don't like is not having the ability to fine tune the gear ratio like changing a sprocket, one tooth makes a difference. The other is I'm not sure on what gear ratio I'm needing.

Option #2, Put the engine inline and run a long chain to a Quaife FNR with a limited slip, this will complicate the build as I would need to build a IFS rear suspension, but this route I think would be more efficient and the ability to fine tune the gear ratio would be optimal. Down side it long chain, I think it would live but making repairs to a car 4 inches off the ground in the middle of the night not good.

Opinions please.


09-29-2013, 12:43 AM
Go with the drive shaft/Datsun rear end, if the ratios aren'twhat you want , there are a bunch of rear ends that would work.Dependable is what you need and if you build it bullet-proof thats what you'll have.Cheeper in the long run!!

09-29-2013, 08:41 AM
This sounds like a cool project. Is that roadster the two seat sports car that we saw in the states? Some pics of that if you please. Is there a quick change gear rear end that would work for this car? The shaft set up seems like the way to go. Is there enough room between the front shock towers for this engine to squeeze in?

09-29-2013, 08:45 AM

09-29-2013, 08:51 AM
That's the one!

09-29-2013, 08:54 AM
Cool little car,good luck AK,sounds like a fun project.

No chains in my opinion.

09-29-2013, 09:51 AM
Sounds like a cool project AK Im with others about the chain thing. They didnt work well on the first Polaris atvs .

09-29-2013, 10:56 AM
Well the drive shaft idea is the same as a dwarf car / legends race car. Except they don't run the inline reverse. I run a Toyota corolla diff and well they make a few third member gear sets.
And I believe 4.10 but I could be wrong. I'm tired and well I will look into that.
But it's a 1980 Toyota corrola rear axle.

So are you sure that option 1 has only 1 gear set for that rear end. Or may it be possible to get another gear set for that rear end. Or hey you could change it to a dwarf car rear axle and have a ton of options. Hey you could even get to cut the axle and lengthen or shorten it to fit that car too.

I want to say that the axle jig is 139.$ on eBay. It holds the axles so you can weld them your self.

I say this and know it's more work to have to do that. But it would give you a range of gear sets to play with.

09-29-2013, 01:00 PM
I have the Quaife FNR box with lsd in my Busa buggy. It's about a 1000# and about 200hp buggy. Not the best setup, I just had to replace mine. It was almost $3000. with shipping and took almost two months to get from the UK. In Quaife's defense it did take a high RPM shift in a low gear to break it, but it distroyed it and I'm not happy about having to worry about how I shift!

Definatly had to change how I drive going from top loader Ford in a jeep to the buggy, exspensive lesson, lol

09-29-2013, 11:37 PM
Go with the shaft and if the gearing can't be changed in the rear end shorten drive-shaft and add a manual trans.

09-30-2013, 02:10 AM
Thanks for the replies,

The rear axle in the Roadster is a open diff and the the stock engine at 93 hp it is a one wheel wonder :). The LSD is very expensive and really hard to find much less keep clutch packs in it. Other owners use RX7 rear ends, but just about anything will work having it cut down. Talked to a friend who builds Toyota trucks and he thinks the light weight truck axle that is undesirable for large tires would work good. Unlimited supply of OEM LSD and large selection of gear ratios. I'm leaning this way but thought it would be more efficient with a quaife Fnr.
Thanks Jeep401 for real world experience- I'll put that option to rest, and go with the seemingly unanimous opinions of the rear axle with the inline reverser.
Been a while since I posted pictures on this site, I now use a iPhone and the pics are too large. Got a photo bucket account and will work on getting some pics of the car and build.

09-30-2013, 07:45 AM
Sometimes if pics are to large you can email them to yourself and it automatically cuts them down to less bytes. Then they post. It has worked for me.

09-30-2013, 01:34 PM
Alright Nuts, lets try this.

Looks like they are click-on pictures.[smilie=gun_chair.g:

I just weighed the car, came in at 2,065 lbs. With taking out the cast iron engine and trans, hopefully I can keep this thing at around 1700 to 1800 lbs. Should make the car scoot.


10-01-2013, 01:29 AM
C'mon Diablo,lift ya game Mate!:p
http://i953.photobucket.com/albums/ae16/buggybaz/Datsun2_zps5feae085.jpg (http://s953.photobucket.com/user/buggybaz/media/Datsun2_zps5feae085.jpg.html)
http://i953.photobucket.com/albums/ae16/buggybaz/Datsun1_zps1ec4dc39.jpg (http://s953.photobucket.com/user/buggybaz/media/Datsun1_zps1ec4dc39.jpg.html)
http://i953.photobucket.com/albums/ae16/buggybaz/Datsun3_zps97ee6dec.jpg (http://s953.photobucket.com/user/buggybaz/media/Datsun3_zps97ee6dec.jpg.html)

10-01-2013, 05:57 PM
Ditch the rear axle for something stronger with more parts availability.

If you go the Toyota light truck route (which I would suggest), I have a limited slip diff for a Tacoma that I will make you a deal on...........

10-01-2013, 06:10 PM
The 1977/1982 toyota carolla would have a lug pattern of 4/115

10-01-2013, 09:33 PM
Lug pattern is easy to change. finding gear sets and posi's for obsolete rear ends is not.

10-02-2013, 06:26 AM
I would look at a mazda miata rear end.

10-04-2013, 04:01 PM
I was going to suggest a Miata rear end as well. I would graft the whole rear clip in. Performance parts are readily available too. Grafting the front suspension in might not be a bad idea either. Better brakes all around on top of the "modern" suspension would certainly be a good idea with the busa powerplant. There are some FAST Miatas! I drove one once and was very impressed.

03-17-2014, 05:35 PM
[/IMG]Well after the Holidays - daughters wedding ect., I'm finally starting to tear down the Datsun for the swap.


Pulled the motor and started to pull body panels off, oh the rust[smilie=rant.gif] What else would I expect from a almost 50 year old car. I'm going to replace the floor boards but leave all the body work until after I get her on the road - maybe next winter do the body and paint.


Pulled the engine.


Engine mounted transverse and will have a drive shaft going back to the X bracing to a Yoshi supplied Reverser and then to the stock rear axle for now.


03-17-2014, 05:46 PM

She is going to be real tight, on the Roadster the frame rails get real skinny only where the engine needs to be:mad:


So I got out the Plasma and clearanced the frame a little bit.


No room for header primaries so I'll just make a short turbo header:D


03-17-2014, 10:13 PM
This is gonna be SWEET!!!

I was worried progress had stopped since it's been a while, glad to see your still working on it.

CANT WAIT to see it GO!

03-18-2014, 07:31 PM
Thanks Lug, just got busy over the holidays, I'm slow but persistent.


Made sure hood would close, I didn't want to do some 70's hood scoop, I want it to look stock.


Pretty close to hood, I'll have to put some 90 degree elbows to move the throttle bodies down.


Start of the engine mount.


Finished forward mount. I figure I can't build the back mount until I build the header and route the down tube. The steering, engine mount and down tube will be competing for the same space[smilie=banghead.gi:


03-18-2014, 07:47 PM

Here is the start of the header, Knew this was not going to be easy so I used my CAD skills.


The cardboard aided design work like a charm, using 3/8" stainless for the mounting as I'll build bracing off it to hold the weight of the turbo. Hopefully keeping the cracking to a minimum.



Two and Three cylinders 45 degrees down to start.


03-18-2014, 07:58 PM

Basic header layout.


Cutting the donuts to form the collector.


Number one and four cylinders forming the up turn.



Engine and header in chassie, not sure on the angle of the mounting flange yet so that is not welded, I'm thinking of tilting it towards the inner fender to give more clearance for the engine.


03-18-2014, 11:04 PM
Thats awesome work!!!

Up north
03-19-2014, 01:03 PM
Looks like a lot of tedious and time consuming work, header turned out excelent AK

03-19-2014, 02:42 PM
Looking good!

06-10-2014, 02:49 AM

06-11-2014, 12:35 AM
Yea unfortunately I've been hard at it but I'm not dealing with anything good to post here. The car is 50 years old car and I'm chasing rust issues before I can move forward, also waiting on parts.

This is what I've been dealing with, drivers side floor boards, yea that's the frame and floor.


Made some door braces


Made a rotisserie, my plan is to get a solid body and get the car working, then work out any issues and put body back on rotisserie and change color to silver.

Cut out both floorboards and making patch panels all over the car

I did take some "Fun Time" and made the gauge mount

Right now the floorboards are ready to weld in now but need to finish the exhaust, mount reverser and currently starting on the wiring and access without floorboards is great. It shouldn't be long before I have some good pictures of progress.


06-11-2014, 12:42 AM
Yeah nuthin good to post , that was horrible!

06-11-2014, 01:36 AM
Looks like your hard at it!

Great cant wait to see more.

06-11-2014, 10:53 PM
Yeah nuthin good to post , that was horrible!

Haha you funny man bull....

But yea your right rust IS horrible, I'm ready to get to the meat and potatoes of this build and stop making patch panels!


06-11-2014, 10:56 PM
I hear ya, looks great and long time no see.

06-25-2014, 02:39 PM
Here is some Horrible pic for Bull....

http://www.minibuggy.net/forum/attachment.php?attachmentid=30935&stc=1&d=1403710470 Separated the cowl to get at the rust[smilie=gun_gun.gif]
http://www.minibuggy.net/forum/attachment.php?attachmentid=30936&stc=1&d=1403710515 Just a little Swiss cheese.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30937&stc=1&d=1403710593 What is left of the cowl after the wire wheel


06-25-2014, 02:45 PM
http://www.minibuggy.net/forum/attachment.php?attachmentid=30938&stc=1&d=1403710885 A lil grinding.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30939&stc=1&d=1403710885 building a patch.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30940&stc=1&d=1403710885weld in,
http://www.minibuggy.net/forum/attachment.php?attachmentid=30941&stc=1&d=1403711068 And REPEAT again and again.[smilie=ecstatic.gi:


06-25-2014, 03:35 PM
HOLY SCHNIKEY'S that is gonna be fun!!!

06-25-2014, 08:22 PM
WOW! You body guys have some patience!

Do you have a donor car to steal parts from?

06-25-2014, 09:36 PM
I was thinking the same thing bull... About patience, that is.

06-25-2014, 11:40 PM
Nope no donor car, I did however get a set of floor boards from Arkansas that saved me a lot of time:) Don't know about patience, already heat warped the cowl, now need to learn how to shrink metal, I can stretch it all day but shrink it? Had some success with my press - pressing between two flat plates to get out heat warp or dents but the cowl has too many curves.


06-26-2014, 12:38 AM
"I can stretch it all day"- LOL!

It takes a lot of experience.

Thanks for the pics.

06-26-2014, 01:41 AM
Shrink.. a flame, rag and water. And a few hours of practice.
Maybe a day or two

07-02-2014, 12:02 AM
If you have some pointers I'm all ears.[smilie=ext_secret.:
http://www.minibuggy.net/forum/attachment.php?attachmentid=30961&stc=1&d=1404262472 Mounting up the new clutch slave cylinder
http://www.minibuggy.net/forum/attachment.php?attachmentid=30962&stc=1&d=1404262494 Turbo collector is finished
http://www.minibuggy.net/forum/attachment.php?attachmentid=30963&stc=1&d=1404262544 Start of the 2" down pipe
http://www.minibuggy.net/forum/attachment.php?attachmentid=30964&stc=1&d=1404262590 Need to keep the temps down as the down pipe is right by the master cylinders, wraping in header wrap
http://www.minibuggy.net/forum/attachment.php?attachmentid=30965&stc=1&d=1404262627 That header wrap is some itchy shit so I'm sliding 3" over the pipe.


07-02-2014, 12:12 AM
http://www.minibuggy.net/forum/attachment.php?attachmentid=30966&stc=1&d=1404263059 Down pipe taking shape, need to locate the 3" going out the back before I can move forward. Once down pipe is completed I can make the back engine mount.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30967&stc=1&d=1404263059 Flip over the frame
http://www.minibuggy.net/forum/attachment.php?attachmentid=30968&stc=1&d=1404263150 Weld frame to steel pallet to minimize heat warpage.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30969&stc=1&d=1404263271 Cut 4" pipe and weld in.
http://www.minibuggy.net/forum/attachment.php?attachmentid=30970&stc=1&d=1404263271 Need to weld up, brace and then she's ready for the exhaust.


07-02-2014, 12:47 AM
Good god! Half the car's weight has to be in the frame alone!

Fantastic job so far! I certainly wouldn't have the patience for all that rust repair!

07-02-2014, 03:18 PM
I love this build, lotta work but its cool!!!

Sweet way to rout the exhaust.

That frame does look pretty heavy, but Im sure with a turbo busa you wont have any problems moving it down the road

07-12-2014, 04:05 AM
gotta remember, it's just a roadster shell on the frame, frame provides just about all of the structural rigidity. This one really brings back some memories. My brother had a 1600 that we tore down to resto, was in good shape through and through. Had the frame done, engine 1/2 done and doing minor bodywork when he got the boot and the car ended up going to the junkyard. Couldn't stop my dad who wanted everything gone.
Gonna be a killer ride AK!

08-02-2014, 05:02 PM
How goes the progress?

08-07-2014, 01:41 AM
Yea I'm still at it lugs-nuts, just waiting for something good to post for Bull.....

WOW! You body guys have some patience!

Do you have a donor car to steal parts from?

I didn't but now I do, donor car that is - patience eh not so much....

http://www.minibuggy.net/forum/attachment.php?attachmentid=30996&stc=1&d=1407377876 Hung the frame from the forklift, with a air hammer I vibrated the rust from inside. Needless to say I started to have less and less faith in this frame, so the hunt was on and contacted another member of the roadster website who had a stalled SR20 project - so now back to square one with modding a frame - but no rust[smilie=ext_hooray.:

http://www.minibuggy.net/forum/attachment.php?attachmentid=30997&stc=1&d=1407377965 Enter donor car - wish I had this a while ago. Too bad this is a high windshield car so not too many body parts will work on my low windshield 1967. My project is far from complete and my 18 year old son already wants to rat-rod the old frame and the 69 body...[smilie=dunno.gif]

http://www.minibuggy.net/forum/attachment.php?attachmentid=30998&stc=1&d=1407378153 Seems like I've done this before [smilie=gun_bash.gi: At least I'm faster now.

http://www.minibuggy.net/forum/attachment.php?attachmentid=30999&stc=1&d=1407378267 Since I'm redoing this again I decited to lower the engine 1 inch to allow more room for the throttle bodies. I didn't like the "S" curve intake manifold that I planned on, so hopefully this will be enough room under the hood to leave the throttle bodies in stock location.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31000&stc=1&d=1407378483 Needed to cut passengers side as well as the lower cross mount in order to drop the engine 1 inch. Hopefully the turbo is not crowding the inner fender too much, but the idea of having lower center of gravity, better engine to reverser drive shaft angle, and no backyard intake manifold that could cause de-atomization of intake charge at low RPM will make it worth the extra time and $


08-07-2014, 02:07 AM
LOL, Its all good!

Always enjoy your projects.

Congrats on the donor car, done in no time now!

08-14-2014, 12:20 AM
Now that the engine mounts are half done, I'm working on the exhaust and getting that done, then steering before the back engine mount.
http://www.minibuggy.net/forum/attachment.php?attachmentid=31009&stc=1&d=1407978712 This is basically where I left off with the old frame. Took out the 45 degree so that the down pipe will straighten out and pull it away form the inner fender.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31010&stc=1&d=1407978712 Little frame notch.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31011&stc=1&d=1407978905 shorter route for electric dump

http://www.minibuggy.net/forum/attachment.php?attachmentid=31012&stc=1&d=1407978905 I'm using a guillotine style dump hopes it seals.


http://www.minibuggy.net/forum/attachment.php?attachmentid=31013&stc=1&d=1407979068 finish enclosing the frame and currently building lower engine mounts.

08-14-2014, 03:32 AM
My Grandpa stated to show me how to shrink metal, many years ago. He did body work in the 40s and 50s.
Well over 35 years.
You want to use a carbonizing flame, more Ace than Ox.
Better to add carbon than Oxygen.
If you have a dimple, warm center out, Don't get it red hot.
Take wet rag and cool, repeat.
Use hammer and dolly. Work from outside in.
File smooth.
If you have a high area, heat outside in, Repeat as above.
It is a hard thing to master.
I am sure there are many books and video on how to do it.
I wish he would have shown me more.
This is a cool build, keep the pic's coming.

08-15-2014, 02:26 AM
Yep cool build

09-09-2014, 12:46 AM
Lil' more progress, problem is old man winter is coming fast up here, aint looking like I'll make a test run before the snow flies.[smilie=alright.gif]


Finished the exhaust dump


Started to fit the floorboards, new STI seats and where the Reverser will be placed.


Mounted the seat base to the OEM seat rails and made as low as possible.


Spacer sleeves for the Yoshi style reverser, bolt head recessed in.


All welded in.

10-03-2014, 10:57 PM
I'm needing more electrical power that what the stator will give me, so I went with a TomPro alt. The Alt is pretty big so maybe I'll get a 60 amp unit as its pretty tight to the fire wall.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31156&stc=1&d=1412379874 Working on the steering, new hole lower down so it will clear the header since I lowered the engine.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31157&stc=1&d=1412379908 Upper u-joint and needed to make stiffeners for the cowl since there is no steering tube that connects the floorboard to the dash.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31158&stc=1&d=1412380001 Floorboard pillow block

http://www.minibuggy.net/forum/attachment.php?attachmentid=31159&stc=1&d=1412380108 Connects to the lower 1"DD slip shaft, this is way better than the spear of death as my car was the last year for a solid shaft. Datsun went to the collapsible shaft on the '68. Ive heard it called the PCRS on the Roadster site (Post Crash Restraint System)[smilie=wbounce.gif]


11-17-2014, 11:00 PM
Hows it going? I need MOAR!!!

12-05-2014, 07:40 PM
Here you go Lug-Nuts

Once steering was in I could make the rear engine mount
Took off the Tom Pro Alt housing and welded a stud for the shifter.
Shifter half completed, now need to go from OEM shifter location to this shifter arm.
Now swimming in wiring, my favorite[smilie=thumbs_down:.
New Honda S2000 start engine switch where choke used to be.


12-05-2014, 08:11 PM
Well I've been in the parts sourcing mode lately, decided I needed the RX7 rear end and boy did I get lucky! Seems like if you want a GLS-SE from only 84-85 you need to buy the whole car as it is a popular rear end for Roadsters, other less desirable 1st gen RX7's rear ends ect. Well by Craigslisting all the western states I happened on a gen 1 RX7 project and he had sourced a GLS-SE already but not currently in his project so he let me purchase it. So one short truck/boat ride from Colorado it is finally in my grubby hands. Now with axle in hand I looked for wheels, settled on staggered ROTA RB's in the 16 x 7" & 8", a bit big but with having to cut down the RX7 rear should be no big deal. Next tires and man nothing is made for 16" rims anymore[smilie=gun_chair.g: I got some Bridgestone 205/55R16 & 245/45R16 for the rear. Now just need to start cutting down axle, change gear ratio to 4.875 (lowest I can find, supposedly there is a 5.12 but can't find it) and make a 4 link rear suspension.
Had no idea how hard 16" was to find. In hindsight I would have changed the bolt pattern to 5 on 4.5 and went with either 15" or 17" I've been told 17" looks to big and it would have made my gear ratio even worse.
New tires, the fronts are currently discontinues, so thinking of purchasing a second set after Holidays.
They said it wouldn't fit, currently rubbing with leaf springs but with a 4 link with watts or panhard bar should be fine. Probably will have to Mini-tub the rear fender wells also.
I'll be making the RX7 alxe about 1" narrower.
Rear rims are +10mm offset, so I'll try to hit the axle width right on with 10mm spacers and 1/4" from outer fender well, that way if they rub while cornering I have some play. If all goes well and I didn't need the spacers then I can purchase 8" rims with 0 offset in the future.


12-05-2014, 09:26 PM
Awesome work AK.

Was wondering if you have any run time on your motor with the alternator setup? I ask because I had an issue with mine leaking oil due to an undersized shaft (leak came out where the shaft comes through the bearings), but it might be an isolated case.

12-05-2014, 09:47 PM

No I don't have any run time on the Tom Pro alt setup. My shaft seems pretty tight on the bearings, is there play in yours? also it would seem to be pretty hard to leak right there as that does not fill up with oil, matter of fact I was actually thinking of plumbing the turbo return line into that housing.


12-05-2014, 09:55 PM
After I found the oil leak, I measured the shaft OD at 29.75mm. The bearings are meant for a 30mm shaft. I'm working on sorting things out with Tom. Hopefully mine was just a fluke.

12-20-2014, 05:54 AM

Propped up the rear tires and lowered the body down to see where the wheels fit into the wheel wells and measure mounting distances. This is about what I want as ride height, but must wait until I get the new lowering springs from Datsunparts.com. to see where the front ends up with.

Looks like I need 47.375" rear axle length. Thinking this is a +10mm offset so if I take off an additional 1/4" for clearance and an additional 10mm on each side then I'll have fudge room if 1/4" is not enough. Then if it works out next rims I purchase I can get 0 offset.

The frame is a "U" channel with a top cap with a lot of overhang. I trimmed the overhang in hopes that I don't need to narrow the frame to fit the wheels without fender flairs. But this is wishful thinking I'm afraid.
RX7 axle with OEM mounts cut off and getting ready to measure to shorten it up. I'll have to tub the inner fenders of the body and I'll start that next before I start cutting away at this axle.


12-20-2014, 11:06 AM
Awesome work Diablo!
I'm totally more amazed tho.that you can get so much done,considering ALL the time you spend on the phone?:D

12-20-2014, 01:36 PM
Ahh, Busa datsun

12-20-2014, 09:36 PM
Take a baseball bat and roll the fenders. Will get you an inch without changing the look of the flare.

12-30-2014, 05:02 PM
Thanks bdkw1, but I needed to take this all apart anyway, the previous repair and rust needs to be dealt with.

Inner panel is first to go.
Drill out spot welds and take out 1.25" each side. First line is cut line second is bend tab line.
Lots of rust to kill before I can move forward - really the only way I could see to do this properly.
Finding new holes under bondo repair.
This is what the flair looked like under 1/4" of bondo.the repair was not fully welded, guess it held the body filler better[smilie=ecstatic.gi:

12-30-2014, 05:34 PM
You are a Trooper !

12-30-2014, 09:22 PM
Well, you would have had to take them down even if you tried to just roll them. That bondo would have popped right out when you flexed the fender..........

01-01-2015, 12:58 PM
Wayne my friend, you are a gluten for punishment lol! Nice work as always. Love the CAD work concept!

02-13-2015, 07:19 PM
Wayne my friend, you are a gluten for punishment lol! Nice work as always. Love the CAD work concept!

Yea Odyknuck some times I don't know why either. How's that Wildcat treating you? ready for a Apex yet?

http://www.minibuggy.net/forum/attachment.php?attachmentid=31963&stc=1&d=1423857841 Went over to a auto body place and tried out their stretcher and then I needed my own.
http://www.minibuggy.net/forum/attachment.php?attachmentid=31964&stc=1&d=1423857901 The inner fender expansion ring.
http://www.minibuggy.net/forum/attachment.php?attachmentid=31965&stc=1&d=1423857977Now with my own shrinker and stretcher I'm making my own fender flairs.
http://www.minibuggy.net/forum/attachment.php?attachmentid=31967&stc=1&d=1423858707 Welded in, made flair 1.5" lower than stock.


02-13-2015, 07:28 PM

http://www.minibuggy.net/forum/attachment.php?attachmentid=31968&stc=1&d=1423858876 Prepped the frame for POR15

http://www.minibuggy.net/forum/attachment.php?attachmentid=31969&stc=1&d=1423858876 Painting front half of frame

http://www.minibuggy.net/forum/attachment.php?attachmentid=31970&stc=1&d=1423858994 Fresh paint and new parts.

http://www.minibuggy.net/forum/attachment.php?attachmentid=31971&stc=1&d=1423859130 Needing to get final rear axle measurement, I lowered the body onto the wheels. Now my son I pushing me to bag it.



02-27-2015, 06:18 PM
Building the 4 link rear suspension. Needed to move the inner frame rail in for the mini-tub so I can make the attachment points. After the 4 link is done and all welded in I'll cut the outer frame skinnier to match the body and cap it.

http://www.minibuggy.net/forum/attachment.php?attachmentid=32013&stc=1&d=1425064180 Start with 1/8" angle

http://www.minibuggy.net/forum/attachment.php?attachmentid=32014&stc=1&d=1425064180 Cut and form to frame

http://www.minibuggy.net/forum/attachment.php?attachmentid=32015&stc=1&d=1425064375 weld 1" inboard. Leaving top exposed to brace 4 link brackets.

http://www.minibuggy.net/forum/attachment.php?attachmentid=32016&stc=1&d=1425064435 Used a program from a buddy of mine who runs a 4x4 fab shop, probably from Priate 4x4 web site. Took WAG on center of gravity and placement as the car is not finished



02-27-2015, 06:28 PM
Making lower frame mounts, using old leaf spring bushings.

Welding into place, using 1/2" all thread to locate the width and 1/2" tubing to keep holes aligned.

Making lower axle mounts, because I guessed on weight, CG ect in the program I'm putting in 3 adjustment holes on the axle and 2 for the frame.

Mounting to axle.


02-27-2015, 07:53 PM
I always thought the WAG was the radiator cap...so yours looks pretty good. LOL.

03-17-2015, 03:23 AM
http://www.minibuggy.net/forum/attachment.php?attachmentid=32083&stc=1&d=1426557947 went with a reverse watts link so I could have roll center adjustment.
http://www.minibuggy.net/forum/attachment.php?attachmentid=32084&stc=1&d=1426557988 Seven holes but realistically only 3 or 4 will be used.
http://www.minibuggy.net/forum/attachment.php?attachmentid=32085&stc=1&d=1426558430 Broke down and I'm going to fully bag the car, although the front will be a bit of a challenge
http://www.minibuggy.net/forum/attachment.php?attachmentid=32086&stc=1&d=1426558908 All set-up


03-19-2015, 06:31 PM
Opps looks like when I resized it was too large

http://www.minibuggy.net/forum/attachment.php?attachmentid=32090&stc=1&d=1426789650 Reverse Watts link.

http://www.minibuggy.net/forum/attachment.php?attachmentid=32091&stc=1&d=1426789650 7 roll adjustment holes, although probably only 3 are useable

http://www.minibuggy.net/forum/attachment.php?attachmentid=32092&stc=1&d=1426789650 Airbags

http://www.minibuggy.net/forum/attachment.php?attachmentid=32093&stc=1&d=1426789650 Put it all together for a photo-op day.


03-20-2015, 04:25 AM
Good work!!!

Looks like there's a little more to it than just cobbling it all together.

03-30-2015, 05:10 PM
Happened to see your build featured on Speedhunter, very cool!

IAMTHESPEEDHUNTER: Your Bike-Powered Builds - Speedhunters (http://www.speedhunters.com/2015/03/iamthespeedhunter-your-bike-powered-builds/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+Speedhunters+%28Speedhunters% 29)

11-13-2015, 10:31 AM
So, how's the build going?

01-29-2016, 05:39 PM
Has it really been almost a year since I last posted??? Where does the time go...

Mech_head... Yea it was pretty cool to have speedhunter run a bike powered build, and at the urging of the Datsun crowd I submitted it, now if I can only get her done.

Lugs... Been working and need to bring this thread up to date...

Still fighting rust...seems to be a theme here.http://www.minibuggy.net/forum/attachment.php?attachmentid=32709&stc=1&d=1454110547
Finished up the frame narrowing for the mini-tub.



01-29-2016, 05:52 PM
Wanted the Roadster to have all one key so I decided to move all the Hayabusa locks over to the car
I'll have to do the trunk key at a later date once the rotisserie back-bone is removed.

Didn't like the first shifter linkage so I reworked it a little.


01-29-2016, 06:05 PM
Before I finished up the floor boards I decided to run tubing for strength and a nice place to run electrical wires front to back
Been a while since she's had any floor boards. Can't tell you how many times I still try to reach/look and the damn floor board is in the way.
With the floor boards in I can work on finishing up the mini-tub
Previous owner hacked up 6x9 speaker holes, now I'll only be able to run 6.5" speakers in the holes. Inner tub moved in approx 2"


01-29-2016, 06:24 PM
With the rear inner fenders tacked up I was able to work on the floor board/package tray transition. The 4 link upper frame mount was hitting on the body so I had to clearance it by 6"
Car floor about done [smilie=jumping.gif]
Now the seats.... what to do and I'm still wrestling with this issue. I love the low back seat look with or without a roll bar but can't keep thinking high back with rollbar for safety reasons as well as if I want to enter it in the local auto-cross events. No way around it, I'll have to have them.
Also since I'm in a rainy area I need a soft top and the roll bar heeds to be low enough for the frame to clear. Only way to make "look" right is to have the seats head rest cut down. Maybe take 3" out of seat back and leave headrest alone?
Like the roll bar look without the seats...just not so much for banging my head on the bar. Currently make another bar with Audi TT type individual hoops but not there yet[smilie=gun_bash.gi:


01-29-2016, 06:34 PM
More rust removal. Under the cowl was suspect metal and the thought of not being able to do anything about it once the cowl was welded back in place well....Out it comes

It was REAL thin in places with small pin holes. The paint store swore up and down Por15 would hold but with direct rain contact I didn't trust it to hold up.
Point of no return...
the fit up went pretty well, made in 3 parts and angled the bottom two for run off.


01-29-2016, 06:55 PM
Throttle, The OEM throttle is directly below the short lever arm I made. This gave too cable pull vs the peddle throw, so I needed to make linkage. First make short arm with different pulling locations
Made interior linkage with snowmobile reverse linkage. Also the arms on the peddle and small lever have two holes to further adj throw.
Firewall mount is adj to different lever arm holes. Cable is from a Yamaha Nytro throttle. Pretty short cable but gave me the 90 degrees I was after.
Wanted the radiator rubber mounted, so I picked up 4 wheeler seat rubber and mounted them on the radiator
For the frame I made adj stud mounts for the rubber to slide onto. Last will be attaching to the top core support bar but will have to wait until body is finally mounted with the mounting pads. Right now it's sitting on the frame and tightened down for welding floorboards ect.

01-29-2016, 07:00 PM
4-wheeler mounts worked good so why not use them on the intercooler. Mounted rubber right to frame and made studs for the intercooler. With charge tubes probably don't need anything else
Using the OEM Suzuki oil cooler
All three have found a new home.


01-29-2016, 07:36 PM
Good to see you AK!

Looks awesome! Such a cool project.

I wasn't looking for any specific details, but the throttle cable jumped out at me. Is there enough flex in the cable to accommodate for the engine movement? You probably have this figured out, but just wanted to mention it.

01-29-2016, 07:38 PM
Needed to make a speedometer pick-up. I made a bracket to hold sensor that mounts to the back engine mount. Then a piece of pipe with allen head bolts screwed into it. OEM has only 4 pickup points so I wanted too many instead of not enough.
With a speed healer I should get pretty accurate readings.
Coolant routing... needed to have cabin heat as well as cool the turbo so I went with a Yamaha Apex thermostat and took out the stock Hayabusa one. Also I'll eliminate the OEM bypass hose as I'll get plenty of bypass between the heater core and turbo.

Front barb off the thermostat will go to the turbo and the rear will go to heater.

Well that's about where I'm at, doesn't seem like much from last March but at least I'm persistent.


01-29-2016, 07:44 PM
Good to see you AK!

Looks awesome! Such a cool project.

I wasn't looking for any specific details, but the throttle cable jumped out at me. Is there enough flex in the cable to accommodate for the engine movement? You probably have this figured out, but just wanted to mention it.

Bull, I hope so...with the engine solid mounted and it being a 90 degree angle in there it should be fine. The body would have to pull away from the engine and I don't think that large frame will have that much flex in that short of a distance. Although it would be pretty bad if it did.[smilie=scared.gif]


01-29-2016, 08:00 PM
LOL, yeah, the throttle cable would be the least of your problems!

I figured you had it solid mounted.

You gotta be dying to drive this thing!

01-30-2016, 09:50 AM
Good to see your still working on this, and havent let it go by the wayside!

07-24-2017, 09:19 PM
Last month start up.......


I have a question. I replaced the inner torque limiter inner clutch (2011 Busa) with a billet clutch. It turns out that the billet clutch is designed for a lock up style clutch and the spring retaining arms are short causing the springs to coil bind. I can simply put spacers in there but now it's got me thinking of a lock up style clutch. Have any of you guys used the lock up clutch or is that just a drag racing application? With the added weight of the car and a turbo I'm thinking the clutch needs a little help especially on hard launches on pavement. Thoughts...


07-25-2017, 12:39 AM
Congrats AK! Badass!

That's not what I pictured the frame looking like but OK, I can see where your going.

Watch That master switch! The big red paddle one. They are not made like the old school ones. I had one fail almost immediately in the Briggs. I ended up taking the new and old one apart and making one good one.

I think I bought mine from Longacre? I had pics on here of the difference inside, I'll see if I can find them.

EDIT: cant find the pics. If you start having electrical problems, look at that switch.

07-26-2017, 12:37 AM

07-27-2017, 09:53 AM
Can you swap out the towers from the original setup? They are red loctited in, btw.

No need for a lockup clutch on a stock or near stock motor, they are meant more for racing where you can adjust their slip, and make them grab at a certain rpm for consistent hits. I assume you are asking about a single stage.

The busa clutch is pretty robust as is. I didn't bother to take the back torque limiter out since it only acts on engine braking, and the sand really slows the vehicle down, and I'm never in a situation where the engine is being forced to a high rpm.

Oh, didn't see you were going to turbo it. Heavy springs may be enough in that case.

07-27-2017, 11:00 AM
Billet basket and HD springs. Later yr Busa have a better basket already, but billet is still a good idea w turbo.

07-27-2017, 11:55 PM
I thought the Gen II Busa's don't turbo as well as the Gen I because of the higher compression?
Awesome project as usual for Ak.

07-28-2017, 12:14 AM
Properly built, either one will turbo just fine, but the gen 1 can take a few more pounds of boost with less octane.

I've heard the gen 1 cases are a little beefier in some sections, and some of the guys pushing the limits go back to gen 1 cases with the gen 2 crank and head. Maybe it was just the cylinders....

The gen 2 ecu is far more capable though. Addition of boost is easily accommodated without a fuel pressure regulator.

I've seen 6lbs for a gen 1 and 4 lbs for a gen 2 before you need to open it up for mods. I would be careful with boost on a stock motor though, these heavy vehicles definitely tax the motor harder and longer than a bike.

07-28-2017, 07:49 PM
I don't want to hijack this thread but do have a question on turbocharging, please see other thread

09-19-2017, 09:17 PM

My son Tyler took a video and since he's much better than me (cell phone vids) so here it is. Hopefully I can put her in paint this winter.

Well I had it on the road, not for long though I have bad vibration issues. With two drive lines they can clock differently in and out of the reverser, this means fight each other pretty bad depending on where they happen to land. Sometime is seems like they are coming apart at 30 and other times it not bad until 60. With the rear and front at different angles I don't think a double cardian U-joint CV will help either, I need to go to a true CV for the drive lines. I got in touch with the drive line shop in North Carolina who make expensive CV drive lines but have yet to hear back after I mapped out what I was dealing with. Maybe I just need to put in a non plunging CV at the reverser and adapt one to the engine output flange. Another problem I have is there is no cushion in the drive system and so she bangs pretty bad with each gear change. With a solid axle in the rear a Guibo is going to be hard to implement but I'll have to figure it out. Maybe even rubber mount the engine but that's just showing my age. It was pretty fun while it lasted. We only tuned to 2-3 lbs of boost because we kept popping the fuel pump fuse at about 8-9k RPM. The engine tuner is pushing to do engine mods this winter for more boost but we'll see, need to figure out this drive train first.


09-19-2017, 09:35 PM

Man those cars are small, it's like your wearing it. Have you weighed it yet?

Also might look into a guibo joints for the drive shaft.

09-19-2017, 09:50 PM
67busa! LOL.

Roll bar is a little low!

Very cool AK, congrats on getting to drive it.

Has to be hard to not let that thing scream!

09-19-2017, 10:34 PM
bdkw1, yes we did weigh it, 1970 lbs, pretty heavy for how small it is. Came out pretty even too LF 520, LR 490, RF 490, RR470
Yea on the guibo, thinking right after the reverser as in front will make the angle worse.

Bull, You have no idea how many people miss that. My wife said what is bus A? thinking is was tongue and cheek on how small the car is. One coworker said "but there is nothing in that car that's built in the USA. And yea not hard to keep the RPM's down because when the fuel pump fuse blows it kills the whole car. Need to put a rely with a 15-or 20 amp fuse but that easy and there was no real reason to keep going until we can go faster.


09-22-2017, 12:28 AM
Well done Diablo,great to see you finally driving it.Can't believe how small the car is tho,seems your hangin' outa it.
When we talked once on the phone we found wer'e about the same size/weight remember?...BUT not now,been doing situps like a crazyman.
Full extension ol style,300 sups in 13mins 55secs.Lost 10 kgs so far.Used to look like a 10 month overdue prego woman...now just 4 months prego![smilie=ohmy.gif]
We also share the dreaded stutter Mate! Dit dit dit :D

09-22-2017, 01:24 AM
Bazz, Bazz you know the camera add 10lbs....er 20 lbs. Yea I used to think Pilots were small...