Sorry, the 1988-89 MR2 factory SC uses a clutch on the roots blower triggered by the ECU. When boost is called for by either the throttle position, or the AFM then the clutch is locked, the SC spins and boost is provided. Any other time the clutch freewheels and the SC is disengaged. It's quite an elegant system that gives you the best of both worlds, instant boost and good fuel mileage.

 

Got a pic of that setup?
I'd like to see how the air get's into the motor with the SC turned off

 

i was saying you would have to use a clutch on it to have no boost at all.

 

http://www.mr2sc.com/websites/tech/tccs.htm

This will explain how it works but i still dont see how an IC will work before the air gets compressed and heat is added , if u try to cool 70 degree air with 70 degree air at 40mph ur gunna end up with about 68 degree air is it really worth it?????

 

Did you look at the diagram?

The IC is AFTER the SC.

And remember, there are two types of ICs. There are A2A (Air To Air) or A2W
(Air to Water, also called A2L for Liquid).

 

i see that but how would u put an IC after a roots SC like the one that were talkin about for the VG30????

 

its most likely similar to the new JRSC AWIC setup for Hondas with a air/water IC "plate" between the SC and the head(or in this case lower IM)

 

I could take a pic, but it's a pretty compact setup. Basically it just routes the air around the SC using an ABV valve. Like I said, it's a pretty compact, simple and elegant system. Makes a TON of low end torque and with headers and free flow exhaust it makes good HP right up to the rev limiter at 7500 rpm.

If I had the money to have DPR do a good reworking of the head it would probably make another 25-30 hp at 8K or so.

If you go to http://www.mr2sc.com/websites/tech/tccs.htm you'll see three diagrams towards the bottom of the page that will let you visualize it better then a photo will.

 

ahhhhhhhhhhhh Cant be very efficient but i see how it might work!! Referring to the SC Roots IC

 

The point is, if you can't use an IC, it's NOT WORTH DOING AT ALL!

 

not really. i'm running my turbo without an aftercooler and its fun enough. aftercoolers just allow you to turn up the boost more than without since it keeps the heat down which inturn keeps chances of detonation down.

 

you CAN run an s/c on a motor, have not be attached to the crank pulley via belt {IE not spinning} and still be able to run. not very well, but will run.

turbo's and s/c are not completely sealed systems. hence why you can run a clutch system on the s/c and use it when need be.

the s/c on ebay won't work on a the maxima version of the vg30e. read my list of parts needed to make this work, all parts listen are factory issue over the counter nissan parts.


pay attention please

 

I guess I'm just looking further down the road. If your satisfied with the 6psi or so you can run without an IC. But even at 6 psi you'll see a great improvement if you use an IC. Like I said before, I've dynoed an 18hp difference on my 14psi 1.6L between the crappy OEM IC and the IC I had custom built for me by Spearco. I can't imagine what damage no IC would do to my power. I'm sure that next summer when I install the A2W IC instead of the A2A I'll see even more power unleashed.

And since you're probably still running the standard compression ratio even with an IC you wouldn't be able to get more then 2-3 psi more boost before you run into problems.

I run 14psi on my SC. I'm now at the outer limits of what that supercharger can produce. If I spin it faster to make more boost it will actually start making more heat then boost. I now have to either move to either a lysolm blower, a larger roots type or scrap the SCs and go to a turbo if I want more.

I've run, riden and worked on MR2 Turbos running at over 21psi and pushing 400 rwhp on pump gas out of 2L in daily drivers (no freaking NOS either). The ones that last have been well thought out and designed as a system. This includes intercooling.

My objectives for boost have ALWAYS been more reliable (not talking 10k, more like 50K miles) power, with wide power bands to make street driving easy and fun. It also has to make tons of reliable power on the road course. So to me, 6 psi is a waste of my time and resources if I can't take it any farther.

 

i actually should be at about 7 or 8 and i can take it up to 10 non-aftercooled. with one i can run it up to 15 psi but after that the turbo starts making more heat and either doesn't increase power or takes power. this turbo is too dang small.

i've also seen some crazy mr2's. there was one with a white trd wide body kit that was turboed pushing 20 psi or more and there was another with the trd wide body and yellow and black paint. not sure what pressure he was boosting at but i think it ran mid to high 11's. if you've ever seen old school there's a possibility you've seen the yellow mr2. its in the background of one of the scenes. that damn car nearly made me late to my hs graduation.