Rebuilding Baja SAE car into Stadium Lite

[minibajaman]

[Akpilot]

Looks like a doner sled to me
I can't tell if it is a Liquid or a fan, if I had to guess it would be Liquid. *The front looks like it took a hit but you do have some nice skis on that machine. *C&A Pro's are top notch. *Looking forward to your build

Wayne

[minibajaman]

1994 Polaris Indy 440 liquid. *Was in real nice shape until this guy's daughter hit a tree stump or something with it, but the damage is really only to the front left suspension, bulkhead, and belly pan area. *Engine runs great. *It does have 5500 miles on it, but you can hardly tell. *Found it on ebay, bought it for $440.

It doesn't have electric start. *On the way home from picking it up (it was in Maryland) I stopped at a big snowmobile/atv/motorcycle salvage yard. *He just happened to have on the shelf a brand new electric start kit for a '94 Indy 440 l/c. *What are the chances of that, I couldn't believe it. *The only issue is it doesn't have the primary clutch with ring gear like the full kit you can buy from a dealer, but at 1/3 the cost I'll figure something out. *If the salvage guy can find a used clutch that will work he will just swap parts with mine, or I can probably find one on ebay cheap as well.

The sled does have reverse, but I haven't decided what I'm going to use for the drivetrain yet. *Does anyone think a Sportsman 500 gearbox would hold up to the power and rpm's of a 440 liquid? *I ask because the buggy is already set up for Sportsman axles, and bigger joints like 930's wont fit because of the close spacing on the 5 link suspension points. *I know the Polaris axles will handle the power, but I need at least the splined shaft they plug in to. *So I could either: *buy that shaft new for $160 (the salvage place only has complete gearboxes for Sportsmans), try to find a Sportsman 700/800 rear end on ebay (~250), or the salvage guy would trade the rest of the sled I just bought for a complete Sportsman 500 gearbox with high/low/reverse. *The other option is to get a shaft splined to match the cv joints (not sure on cost) and run a chain from the sled chaincase between them. *Once I get the parts modeled and put it in Solidworks I can figure how what will work out best for size and weight.

[whiplash]

Looks like a great buy Mini, I can't wait to see that little bugger in action! Should be fun!

[minibajaman]

I have been thinking about what to do for the exhaust pipe. *It seems like cutting up the stock pipe would be difficult and impractical and really messy and not worth the effort. *I really don't feel like trying to make a pipe from scratch either, sheet metal working is not really my forte. *I was looking into aftermarket pipes and called Aaen Performance, and they can sell me a pipe that is not welded up, but is just a bunch of cones and sections that I can rotate and weld to fit as needed. *It is lighter than stock and comes with a silencer and everything for around $150. *I think I'm going to go this route unless someone has a better idea.

[K-fab]

The cone setup is pretty much the way to go. *Done correctly (good brazing, matching & such) they can be a work of art. *

Back in the early 80's when the manufacturers were able to run full factory bikes, Honda had the most beautiful hand made cone section pipes on their motocross bikes. *Titanium cones, perfectly welded together. *Cool rainbow effect at the HAZ around each junction. *Man they were cool. * (sorry, getting nostalgic on you.)

[minibajaman]

I haven't been making as much progress recently as I would like. *I have the car mostly stripped down and cut off some the members in the rear that need to be changed. *I ordered some tubing today and will order the exhaust pipe and radiator today or tomorrow.

I have the basic layout drawn up in Solidworks. *I think what I might do is get the exhaust pipe figured out first (get it as compact as possible) then use that to determine the final engine placement. *I am going to use the sled's reverse chaincase and then run another chain drive off of that using 530 chain. *I am waiting for a quote on custom making a final drive shaft to mate with the Polaris CV joints that I have before I buy the Polaris part and modify it.

Question on carbs, what is the maximum angle they can be run at? *On my engine the carbs basically stick straight off the back, so if the cylinders are vertical the carbs are horizontal. *If I rotate the motor 10 degrees off vertical, the carbs will be 10 degrees off horizontal. *Will they still work ok like this or will there be issues? *I know on Briggs engines they say up to 15 degrees is ok. *Also, should I make an airbox or just run filters directly on the carbs?

[plkracer]

I'm not sure about the angle they can run at, but 10 degrees should be fine. A lot of slopes that snowmobiles climb are a lot steeper than that. Concerning the carbs, if they had velocity stacks in the sled, I would try to use them. Funny things happen when air can't enter the carb smoothly.

[Akpilot]

Mini,

With the pipe kit I got from Crank Shop, sounds a lot like the kit your refering to, it was in the configuration of a stock exhaust system. *It has long swooping curves that fit into the belly pan, this does not fit well in a buggy. *The best, tightest curves, is from the Arctic Cat Fire cat series. *They wrap around in nice tight bends. *I cut a sliver out of the cat head pipe and collapsed to get the diameter I needed to match the stock Polaris pipe. *It is much easier to collapse then try to make a bend tighter IMHO, I would look into Cat pipes, say a F-5 pipe, before you buy. * I used only the first 18" or so of a F-7 pipe then finished it off with the stock Polaris pipe. *The bends are nice and tight, cut and rotate into what fits, then collapse to your desired diameter and weld. *If you have a Cat shop near by see if they have any take offs or cracked pipes they'll sell cheap, I got my for free it was cracked.

Wayne

[minibajaman]

plkracer, the carbs did not have any velocity stacks so I'm probably good there. *On the angle, I agree that when driving the carbs are exposed to all sorts of crazy angles but there is sometimes a static recommendation for sitting flat and idling. *Most vehicle applications I have seen keep the carbs as horizontal as possible in a static configuration.

Wayne, I was planning on getting a pipe from Aaen that is unfinished (not welded up, just the sections) so that I could then rotate it to fit. *The arctic cat pipe is a good idea since they do bend around quite nicely. *There is a sled salvage place not too far from me that might have one. *I might still get the Aaen pipe since I don't want to have to use any part of the stock pipe if possible.