Compound Forced induction
 

because ive never seen a thread in here on it, i though i would start one

as anyone ever seen, hurd read etc an rx7 running a system like this? i searched all my fav search engines and couldnt come up with anything

for thoes of you who dont know what this is, from my understanding its using a turbocharger and supercharged together, benifits from both

i know that anythings possible, but its it theasable to get a turbo and supercharger under the hood of an rx7? seems like it would be a tight fit

anyone got any thoughts

-Jacob

Rick Dobbertim(sp?) did it to some GM POS in the 80's. He had a big-block chevy with twin turbo's feeding twin SC's

someone posted that a while ago... last time i checked someone out there was working on that... don't know much about that though... to me that's just a waste of good money, maybe it's good for someone else :confused:

Agreed!

it did seem a bit expensive, and there is probly a much cheaper/easyier way to get the same #'s

i have the march issue of Turbo infront of me, and they built MR2 with the 94 v6, and fitted it with a compound system

without either system hooked up, they got 181hp at like 5k,

with just the supercharger the got 100 at like 2k and it climbed to 250 at 6.75k

running the compound system they got the same 100ish right at 2k, but then it got 250 5k, and at that point they cut the run, from what i read i guess it wasnt fully tuned at that point

cool concept, but i guess the more i think of it, the more show/proof of concept it seems

neat idea never the less

-Jacob

I have heard of this method being used on older European rally cars (not sure of makes or models right now), but rule changes banned it after too many accidents (too much power in too small of a car). I'll have to research this one further.

I can see using this system to make up for the disadvantages of each part. Superchargers make power immediately, but drop off at higher RPMs. Turbos have to spool up, but then have the ability to make huge power.

You can use this system with a huge turbo. The supercharger will help on the low end until the turbo takes over, then wham! - see ya.

Due to the complexity of the idea, it would take a large amount of time, research and money to make a system that works really well. The Turbo article shows that you can throw a system together, but it won't make as much power as a well engineered stand alone system. There would also be issues just trying to fit all the stuff in the engine bay of a car. The RX-7 is pretty roomy in front of the engine, but it would still be tight.

the ability to make up for each components loss's is a points that was made in the artical

im still new to the math involved with boosting an engine, but the artical made a point to say how the majestic T-76 was putting quite a bit of boost at 3k

-Jacob

there was a recent sport compact car to do it. 94 integra b18c1 LS motor. Turbo for high boost supercharger for low boost. IT made over 400hp on a stock bottom end which is god awful crazy for a honda. -if you ever see it it is the meguiars integra but this is about a year old news -Gabe

i think it'd just be much easier to throw some nitrous on there to spool the turbo rather than farting around with all that piping.

im guessing your talking about this car

http://www.teammeguiars.com/feat_typer.asp


thats freaking insane, tobad i cant find any pic's of the engine bay

-Jacob

that is true

but with the compound system, there would be no bottle filling

This is popular with the 88-89 SC MR2's. Not many guys do it, since it's so costly and such as hassle, but if you want info on it, that is where to look.

It's a very good concept, but pretty hard to integrate the two systems properly.

From that meguiar's car it seems that HKS was the one that made the "twin charger" as they called it.

i think the money saved from customs fabrication could more than make up for the bottle fills.

i was wondering if someone was going to say that

your deffinetly right, and as of now i dont see it as a superiour setup, i just would rather have that setup, and not have to worry about filling up my bottle


on the other hand i havent found anything about someone putting this type of system in a 7, but i wont give up

-Jacob

This whole supercharging/turbocharging setup is infamous in one thing and one thing only

1980's Group B rally cars. Specifically the Lancia 037 S4 which included a turbo and supercharger. It made 327hp and has a torque curve that wasn't a curve but a flat line from 500rpm and on up.

As far as street car is concerned, it is impractically, horridly hard to tune and prone to breakage due to the heat put out by both the turbo and the supercharger. I have only seen and heard of a few with such setup, all running untuned and prone to detonation like a 13bt on crack.

Of course such a setup provides instant boost and and throttle response like a horse jockey.

i don't have any problems with it, it just seems like a pain in the ass to me. besides, nitrous is fun:rock:

which would kick ass and id love to have it, but with the costs involved, will probly stay a dream


i use to think it was cheap, almost cheating, i dont really know why, i was probably being ignorant, but now i totaly agree, and some day when my car runs, whatever year that is ill probly have a bottle in my car

-Jacob