Hi guys,

I am a new member to this forum, I am a member of the Snowest forum, but it has been down all weekend, so in order to satisfy my snowmobile forum addiction, I decided to come check this one out.

Here's a project I have been working on.

It is a 2001 Skidoo Summit with a Holset HY35W turbo off of a 2001 Dodge Cummins Turbo Diesel truck.

It's kind of an experimental project, but if it works like I hope it will it should put out 200+ HP. There are at least 2 other sleds out there that are running this turbo, one of them is a 2003.5 Skidoo Rev Summit, and the other is a Polaris 800. The turbo Rev Summit absolutely rocks from what I have heard.

If I can figure out how to attach some pictures I will post some.

Later,
Randy

Here is a picture of the chassis, as you can see it still needs some finishing touches.

Here is what the project started as... a bare bulkhead.

Then I added a CR Racing tunnel.

Another angle of the chassis.

Another underhood pic.

Yet another underhood pic. Does anybody know if there is a way to attach more than one pic to a post?

One more under the hood.

Nice sled there AB(thats one seriously large turbo(even by automotive standards)Just a couple of questions?Is that pipe an end outlet with the pop off valve on the centre outlet ?If so what happens to the clyinder mixture when the pop off opens?As i have never seen that exact system i was wondering if it is something that is popular out west?Let us flat landers know how that puppy works when you get her done(Im jealous)

The pipe is a center dump design, the end of it is just welded off. I wouldn't exactly call these turbo systems popular, but there are at least 2 other sleds out there running this turbo. I am planning on doing some dyno testing on this setup once I get the thing running, I will let you guys know the results. You are right, this is a large turbo, but from what I have heard the lag is not bad, the power is supposed to come on quite smooth actually. The upside to running a large turbo is I should really be able to crank up the boost and make some huge horsepower.

Nice piece you have there AB. Are you doing all the fabrication yourself? If so, it looks like you have a real talent. I couldn't help but notice that there are no lines off the carb tops to equalize pressure on top and bottom side of the slides. Under boost, the return spring will not overcome boost pressure when you lift off the throttle. It will stay WOT. Have you considered these areas in your design? How are you oiling the turbo?

Keep up the great work. It looks like a lot of fun. I hope it works for you.

rotax, I was told that on the flatslide carbs it is not necessary to run boost pressure to the top of the slide because the area of the slide is a lot smaller on a flat slide carb than on a round slide, plus the flat slide isn't sealed all the way around like it is on a round slide carb, so the boost pressure can make its way to the top of the slide internally. I'll be thoroughly testing it on the dyno before it ever hits the snow, just to be safe.

I have done most of the fabricating, but not all of it. As much as I would like to take credit for the pipe, I had Neil at NPP in Edmonton build it for me. All of the chassis work and installation of the turbo was done by me. Also one of the other members of the Snowest forum has built the boost bottle, sump for the turbo, steering post, and gas rack.

I am oiling the turbo with an electric oil pump that is designed for NASCAR cars to pump the gear oil in their differentials through an oil cooler. I am adding a rectifier and a battery to power the electric pump as well as an electric fuel pump.

Looks like a good job to me. Tunnel looks awesome. I am suprised by the lack of intercooler though. I've seen other set ups with them. Also, seems to me like you will be sucking a lot of hot air with the intake between the pipe and the motor but maybe it wasnt possible to route it out over the chaincase or something?
Ryan

I agree about the turbo sucking in hot air, I'm planning to duct the air intake up and out of the hood behind the windshield. The air filter is basically only on there right now to keep dirt out of the turbo during construction.

About the intercooler issue, I have been debating about whether to put one in or not. The problem is with this being a mountain sled, a lot of the time it will only be going 20 or 30 miles an hour through the trees, and when the powder is deep you get a lot of heat build up under the hood. Without adequate airflow, an air-to-air intercooler can turn into an "interheater" pretty quickly. For now my goal is just to get the thing running and making boost, once I have achieved that I will begin to look at making the system more efficient.

Great project AB,it sounds like you have put great deal of thought into it ,let us know how it works out ,Best of luck

I take it all back, you are two steps ahead of me!
Ryan

Here are a few more pictures of my project. I've got the chassis pretty much done, complete with 159x16" Rev track, Fabcraft carbon fiber front end, and MODS skis. Just a few more finishing touches and it will be time for the maiden voyage.

another pic

'nother one

another angle

last one, I promise

That is awesome!! How is the out-of-the-hole performance with the turbo compared to a non-turbo doo 800 twin? does it take awhile to get the turbo boost up?

Brian

Brian, I haven't actually had it running yet, so I can't say how the off the line performance will be, but I am expecting it to be as good or better than the stock 800. In an effort to make the sled as responsive as possible on the low end I switched to 38mm roundslide carbs, and the cylinders are stock,unported, just cleaned up a little, and the pipe dimensions are similar to stock, and the compression is 13.2 to 1, so it should make for a pretty snappy package. One of the other guys on Snowest that has a similar project has already been testing his on the grass and says there is no problem with lag if you keep the clutch engagement RPM high enough. His machine is engaging at 5200 and he says there is no noticable lag at all. I'm really getting anxious to pull the trigger on this thing.

EDIT: I have changed the carbs since the earlier pictures were taken, those are bored out 40mm flat slides in the first bunch of pictures.

I spoke with Chad at haydays about his tunnels. They sure do look sweet. I am thinking about installing one on my Doo.
How difficult was it to install? Did you buy his coolers or another brand?
Any advise would be appreciated.
Thanks

Pierre

The tunnel swap is a pretty large project. The hardest part was getting the existing one off, the rivets Skidoo uses are ridiculously hard. My install was a little more complicated because I did a drop and roll at the same time, but just a straight tunnel swap shouldn't be too bad. I would guess it could be done in a weekend.

I just used the stock Skidoo cooler, it fits in there fine.

When are you going to ride this beast?? Im looking for comments on the first ride :D

Wow thats sweet, I hope it comes out awesum!! I was wondering about how the jetting works?

First ride was on Monday, then went out for a day ride on Tuesday, everything went surprisingly well for a home built project, had a couple minor issues such as an oil leak on my turbo oil feed line and a clutch alignment problem, but for the most part it was a success. There was some lag with my old clutch setup but I increased the engagement RPM and added weight to the primary and now the lag isn't a problem. Olympic, once a jetting baseline is established jetting changes are made via adjustable power jets.

I was wondering if you had to make it rich untill the turbo comes in, because I know on a dump truck for example they are set rich. When a big truck with a turbo starts off black smoke dumps out of it untill the turbo kicks in than it is where its supose to be.

The power jet is fed by a fuel line from the float bowl, and the float bowl is pressurized with boost pressure. So when the turbo is not making boost, the fuel is only supplied by the main jet, but when the turbo is making boost, the float bowls pressurize and fuel is forced through the powerjets, so fuel is supplied by the main jet AND the power jet. You won't get perfect fuel delivery throughout the range but it's close.

wow thats pretty sweet

do you not plan on riding that thing at night?? im not seein a light?

is it under the bottom of the windshield or something?

nice sled