Has anyone out there experimented with different turbo sizes? Any problems running the MSD with fuel injection, lights etc.? if you did install a turbo where did you mount it? It was a bit tight but I sandwiched it in between the radiator and the engine. Now i am just debating wether or not to install it under the seat.

 

I had mine installed under the seat at one time but went back to the forward position because it spooled up noticeably quicker and ended up stepping up another 2 sizes. Talk to Kelly at KMS he knows these systems better than anyone else and has done tons of R&D developing his turbo systems. Are your running EFI or carbs?

 

On a 650cc engine? What make do you want? Depending on boost.

Schwitzer: 3LD-168 Turbine area should be around .68 or smaller.
With an Airesearch you can go T3,T4. Trim should be J-1 and A/R should be N-.32
With a Rajay go with a 377B25.
On all models you will have to run a wastegate to dial what you want.

 

I'm running Kelley's efi and just switched over to the methanol. I don't seem to have much if any turbo lag, but then again the advance the msd is giving might be helping that area. I tried (though did not succeed) not to spend too much money (that I really didn't have) but I don't give up. You guys know what that's like. Anyhow I ended up with a T-25 and on full boost I've seen it around 11-12psi. So far , though not tested for any duration it's worked. How long it will keep working ????Thanks for the reply, I have spoken with both Kelly and his wife. She's the business lady, and he is a very sharp guy that puts out some clean work. I am actually waiting for him to send me a different map for the EFI.
Thanks again,
Rob

 

Thanks for the info Doc. In regards to turbo sizes, where does a t-25 fall into in the line up of turbos you listed? I am also running a 3"exhaust into an aftermarket pipe, do you think that might be a little too large?
Thanks again for your info and response.
Rob

 

Rob, the T-25 is a Garrett product. I have never dealt with Garrett. A T-25 is a small cartridge turbo. Meaning the center section is very small. This is good for a bike/quad app because, as you know, there is not much room to mount things.
As for what is good for your app, you can put a number of sizes of turbin and compressor snails on any given cartridge. In other words, I can make a t-4 fit a 283 SBC all the way past a 500CI motor. It's all in the trim sizing. If you want more boost than you have now, just call up the people that your dealing with and they will be able to give you the size snail your motor needs. They might not get every last ounce of HP out of the thing because of motor set-up ect, but they know what they are doing if they have dealt with turbo's for very long.
Your almost running 2 atmospheres in your motor. That means that your 650cc is now thinking it's a 1300cc in size. Yes, it's taking in that much air!!!!!! Make damn sure you have a BIG air cleaner on that thing. The bigger you have the more it will cut down on lag.

As far as the pipe size goes, the BIGGER the better AFTER the turbin. Now if you are talking about before the turbin, that is a touchy subject. Just like header size on a N/A motor, you can go too big before the turbin. You usually don't have to worry about pipe size before the turbin because the maker of the kit will supply you with the correct size pipe. When you have too big of a pipe before the turbin you will have more lag but also more top end. As you know, you don't worry about top end with a turbo system. I don't at least!!!
I screwed myself once by going too big on a cross over pipe on my set-up of a SBC. I went and bought a Corrvett 2.5" when I should have just stuck with a 2". I payed lots of $$$$ and got worse preformance with that 2.5".

It's all a numbers game and how much you want to spend!! Have fun with your "snail."

PS. Your doing the right thing with the EFI. All of my stuff was old school carb/turbo combo. Although nice, it never did work the way I wanted it to. I now bought an Accel puter. We will see how that works!!! By the time I have time to put it on the engine, we will have no gasoline in the world.

 

Well the nickname "Doctorturbo" couldn't of fit you any better. You are one savvy person. I really appreciate all the information. The filter I have in the pictures I have posted is not the one i am running. On the exhaust I am running a 3"SS header i made to mount and rout in the same way the factory one did. From the head to the turbo I am running a 1 1/2"on each exhaust port to the turbo. I don't have the $ to pay anyone to fab my goofy ideas so I do what i can in my garage.
Thanks Again Doc.

Rob

 

Thanks for the compliment Rob. To say your quad engine is busy is the understatement of all time!!!! Looks very nice. With 12 LBS of boost I bet it really pulls.
Someone on here said that turbo's were going to start making a big impact on the quad world soon. I agree. Carbs and points type ing. systems worked ok with turbo's, but with todays computer controlled systems they are light years ahead of the old school stuff. I learned that one day when a Grand National raced me in my BBC Nova. He beat me with a 6 cyl. engine with his stereo and AC on!!!!! That was the day I started to respect computer control systems and how well they worked with turbo's.
If I have some time I will put a computer controlled turbo engine in the Vega in my profile. Next year I think I will be able to talk the owner into a supercharged engine.
If you want to try something that really worked well for me was compounding nitrous with a turbo. I know nothing about quad racing so the two combined might blow your tires off the line. If you can hook it up, it really works well. A plus with this system is the N2O is only on for maybe 2 seconds at the most. By that time the boost takes over and your gone. A small bottle lasts forever.
Good luck with all your projects Rob. Remember; too much boost and the engine goes BANG!!!!!