Install the app
How to install the app on iOS

Follow along with the video below to see how to install our site as a web app on your home screen.

Note: This feature may not be available in some browsers.

  • Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

Turbo Mountain Max

I'm still looking to turbo mine, anyone have thoughts on what size of turbo would work? I'm thinking Garrett GT2871r since that's what most 2-stroke Polaris 700/800's and others are using. I'm running a single pipe because of clearance issues, but if it works good, I may attempt the triples with a turbo. Right now I have a T3/T4 journal bearing turbo I wouldn't mind trying, but hear of constant lube issues when running journal bearing turbo's. Any info helps.:face-icon-small-hap

im new to turboing two stroke sleds (who isnt tho) but defiently not new to turbo setups in general, i would definetly say just bite the bullet and get a ball bearing turbo, journal bearing turbos are so damn finicky when it comes to lubrication, to much, too litle etc....

im also thinking about boosting my 700 mm, but i will be definetly fuel injecting it first and that will be a whole other project in its self and definetly wont happen till this season is over, if we even get a season here in oregon....

you would probally be ok with a 2871 but i would more likely look into the 30r's.
I would never dream of running an ebay/knock of turbo on any of my cars but the fact is some of them are being built better and better as the days go by and the price difference is incredible, i might end up picking up one for the initial setup but it will definetly be a knock off of the identical turbo i plan to run for the final setup.

In my opinion the actually physically mounting the turbo and running pipes/lines is the easy part, i plan to focus more on making it run properly and honestly i just dont want to mess with the carbs which is why i plan to ditch them in favor of microsquirt.
 
carbs are super simple if you just think about them and what you are doing while adjusting. plus if you make an adjustment you made an adjustment you dont need to wonder if your lamda is good. or if your 3 bar sensor is placed in the box correctly.

2860 on a 3 banger yami. unless you ride at 1000' of elevation then a 2871. no more though or else it will be hard to clutch out the lag.

for sur spend the bucks for a ball bearing turbo. tons less headaches.

JMO:face-icon-small-hap:face-icon-small-hap
 
I'll be riding at high elevation, from 3000' to 8500' I'm still looking for a BB turbo. I won't be finishing my turbo MM project until next season either. I was going to start on it this winter, but got burned on a turbo,that set me back a while. Now I'll have to find another or run the journal bearing T3. I've seen quite a few kits using greddy 16G journal bearing turbo's, I hear they work well and see their cheap.

I'm going with power-jets in the airbox tubes, I'll try to post a pic of a similar design.

What are you using for throttle bodies with the megasquirt setup? I've been looking at their site and it looks interesting.

Turbo airbox.jpg
 
Here's some pics of the kit I bought. It's for a Viper, but I'll be installing it on my MM700. Don't have a BB turbo yet. I have pretty much everything else I need for the build.

turbo.vip2.jpg turbo.2.jpg turbo.6.jpg
 
I'm hoping for 160HP or better. Not really looking to make a ton of HP, just want good power at high elevation to turn a longer track. I'm installing a dropped & rolled tunnel too, it should all make a big difference.
 
I'm hoping for 160HP or better. Not really looking to make a ton of HP, just want good power at high elevation to turn a longer track. I'm installing a dropped & rolled tunnel too, it should all make a big difference.

You mean a dropped and rolled chain case. I would love to see the finished product!
 
From what I've seen, all that needs to be done on these sleds is move the case down, cut off a couple mounts and re-weld them in a different spot. At least with the Ekholm tunnel. I'll be posting pics of the build. The tunnel already has a bulkhead with a drop & roll so I just need to do the mod on the chaincase. Going to see about a new ball bearing turbo next weekend, hope this one will work! Borg Warner TO4E
 
I'm hoping for 160HP or better. Not really looking to make a ton of HP, just want good power at high elevation to turn a longer track. I'm installing a dropped & rolled tunnel too, it should all make a big difference.

Can't a person can get the MM700 to 160hp WITHOUT a turbo?

I would think you would be STARTING at about 160 to 170hp with a triple piped turbo on a mtn max. Race gas....200+?
 
I'm sure you can. From what I've read they make 140HP with pipes, however all those calculations are done at sea level, so you can knock off horsepower every time you go 1000' higher. Where I live the valley bottom is 2500' and we ride up to 9000' at times, with that kind of altitude gain a N/A engine will lose 30% or more of it's horsepower. With forced induction it can make the same horsepower at high elevation provided you have an adjustable wastegate and a big enough turbo. I'm looking for something reliable, low boost and consistent power, a modded out engine would take a lot of tuning to keep it running right, I know a turbo will too, but I like the idea a lot better.
 
i did a turbo 700 the year dan sold his 700 turbo.
used a turbo from turbo doc in ogden ut. think it was an arodyme.
move the turbo to the end of the pipe.
as the turbo boost went up i needed to boost fuel preasure.
dont remember lag on botom end.
just would get it running good and burn down clutch side.
but what fun when it ran.
 
I sold that kit to him. It was built by a guy up in Northern Alberta, got a bunch of things wrong though. I finally got all the proper parts together to install it and have it run right, but picked up a TM8 for cheap that needed work (My current sled) so I didn't have time for both projects. Ended up selling both my MM's and the turbo kit separate. It's cool that Sam got it running
 
I sold that kit to him. It was built by a guy up in Northern Alberta, got a bunch of things wrong though. I finally got all the proper parts together to install it and have it run right, but picked up a TM8 for cheap that needed work (My current sled) so I didn't have time for both projects. Ended up selling both my MM's and the turbo kit separate. It's cool that Sam got it running

Yeah. Thanks for the turbo kit. Mm700 sounds epic on boost. It definitely needs race gas or 100LL. COOKED a couple pistons and cylinders without the proper octane. I did not run the turbo this year. I’ll be building that project again in the fall.
 
  • Like
Reactions: K45
Premium Features



Back
Top