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I have a Indy 500, 98' carb. I want to put a turbo in it and make it trail friendly with plenty of power. I have enough knowledge of how it would work but I am still not sure how it would act with a push through system. (turbo pushing into the carbs). I know carbs dont understand pressure, but I read on details how to make it work but they were not very clear. Anyways, does anybody know how I could get this to work? I can get all the parts to make it work.
 

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I'm just finishing up a turbo installation on my Ski-Doo, and you better be prepared for quite a bit of work (not to mention trips to an auto parts store). I have CarQuest and Napa salesmen stop by daily for my business, so I didn't really have to hunt for simple things (fitings, air lines, fuel lines), but I've spent the last two months researching and getting everything I wanted. I'll give you a little breakdown of what I did, and if you want I'll send you some pictures to give you an idea. I tried everything I could to get any help I could on the setup, but NO ONE seems to want to help. I've never been so discouraged as when I assumed someone would be decent and help out, but very few people offered anything. Those that did seemed to have done what they could, but they were the ones that didn't have much information or knowledge themselves. In the end I had to figure it out on my own, and I suggest the same for you. I'll tell you what I can, though, because not everyone is as closemouthed as it would seem.

I purchased a used Aerocharger kit from Utah, but most of it was (sorry to the seller, because she was EXTREMELY nice and willing to help) pretty much junk for what I wanted. I'm very picky and a lot of it looked pretty bad. The first step was to build a new air box. I used a 4" ID aluminum pipe and welded 2.75" pipes on the bottom edge for the carbs, a 1.75" pipe on the top for the charge air tube, and drilled and tapped 10 1/8" pipe holes for fittings. The carbs were drilled and tapped at the caps and on the engine side to accept barbed fittings and they were all attached to the new air plenum along with the bowl vents from the 38mm Mikuni carbs. I had 290 and 300 main jets before (Ski-Doo's are always smaller on one side), but I'm running 480s in each carb now. I'm a little rich, but better safe that sorry to start with.
I used the pipe the girl from Utah sent from a 670 and chopped/re-attached the end pipe and turbo flange on to get the placement I wanted. I cut the (very small) can appart and put it back together in a manner that allowed me to use the original hole in the pan for the exhaust. A few other modifications were made (mounting brackets with rubber bushings to get a solid fit that could take some vibration) and then the entire exhaust was sent to Swain Tech coatings (google them if you don't know about them) to have it ceramic coated. At the same time I had a set of pistons done, but they're not installed, yet.
I replaced the stock gas tank fitting with a threaded brass one (3/8" barbed) and drilled another hole on the other side at the same height. These are for the fuel feed and return. I purchased a 45psi fuel pump from Napa and bought a new Mallory drag racing bypass fuel regulator. The one that came with the kit from Aerocharger is a cheap nitrous regulator and pretty cheap looking at that. I ran 3/8" fuel line between everything. The fuel pressure must be a rising rate model (they are more often referred to as fuel pressure regulators with vaccuum control). This will increase the fuel pressure as boost increases. The control barb is run to the air box as well, along with one of the barbs on the turbo. If you're not using an Aerocharger you would probably run a line from the air plenum to the wastegate and a boost control valve. I'm planning on running my boost control valve (when it gets here tomorrow) off of the middle barb on the aerocharger control actuator.
The setup is far from complete, but we're getting there. Amazingly, after two months apart and all of this crap the sled started up on one pull (after the fuel pump filled the carbs and it was primed). I'm running on 100 octane low lead aviation fuel. You can get it easily from any small airport. This was 2.85 a gallon. High octane is great insurance against detonation.

To give you an idea the first pull was last night (January 18th at midnight), so this is all quite fresh. We've got a way to go as far as tuning goes, but when the boost kicks in you had better hold on. There isn't anything like it. This little 500 puts out about 90 hp or so, and we're guessing we're getting about 160 hp at 5 psi with the aviation fuel. We need to do some clutch work, as well, but so far it's more than met expectations.

There are about 1000 things I left out (gauges being a HUGE one), but this is getting pretty long. Let me know if you want some more.
 

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What is that supposed to be a pic showing us sesnopro?? Besides the obvious engine on the sled.
 

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Snow Freak said:
What is that supposed to be a pic showing us sesnopro?? Besides the obvious engine on the sled.
Umm...How about the turbocharger system on the right side coming from the airbox in the front.......
 

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Ohh haha i didnt even notice that!:p i saw the thing going to the front but didnt know what it was.
 
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