m21sniper

Sublimate- "Obviously a rear turbo will keep underhood temps lower than an underhood turbo, but do you think it'll be much cooler than a SC? Yes, a SC gives off heat due to it's inefficiency, but I don't think the difference would be big."

That's one of the very few advantadges a SC holds over a turbo- significantly lower underhood temps.

A rear mount turbo takes that away, and if the plumbing has an excellent ceramic thermal barrier and no underhood air to water intercooler- sure, it could even get close to N/A temps.

m21sniper

Chris- "So do I!!! Actually, a turbo 'costs' NOTHING to drive... exhaust gases that normally go straight out the tailpipe do it."

Driving the turbine still causes some drag and backpressure in the exhaust stream, so there are still losses, but nothing like an S/C at a comparable boost level.

m21sniper

jyoon- "how are people managing fuel control in boosted cars, whether it be turbo or sc?"

I think most of the S/C kits are just running RFPRs. As far as turbos, Herr-Kuhn is the one to ask about that.

G Man

What MY will the kit work with. My guess is it will be for the 32 valve cars and the OB's will be left to watch from the sidelines.

IcemanG17

Hmm
A fourth concept to join the big HP battle...current contenders: Stroker (proven)....S/C (two systems...big power for modest $$$)....twin turbo (still developing...shows great promise) & now rear mount turbo? All have pros & cons....it would be great to see a head to head test in a couple years when the turbos have the kinks worked out....a 4 way battle to see exactly what is the baddest (& most reliable) 928 out there! My opinon...a boosted 6.5L (probably twin turbo)...big $$$$, but huge power potential!
Brian

chris0626

The drag and backpressure are absolutely minimal. A well designed turbo is highly efficient.

Even an S/C at idle to 1500rpm!

Tony

Have those guys up there in the PACNW thought about emailing or calling STSturbo for some input on a rear turbo application for a 928?
http://www.ststurbo.com/home
Wouldnt hurt.

Im sure they could be a tremendous resource with the ins and outs of a rear system while you guys are familair with the ins and outs of a 928. Would be a good partenership and with enough interest they coudl set up fabrication much easier.

Herr-Kuhn

The rear mount turbo should be able to powerfully sting an equally boosted CS car because it will come on full tilt before redline. I've considered this setup for well over a year now (even before I broke into Goldmember) but somehow I can't draw myself to do it...time will tell. Blown head gaskets ususlly mean detonation is in the picture. Remember, the turbo will make the same boost at altitude, CS will be down on boost at altitude.

Fuel management...now there is a topic for discussion. Can't talk about that with my new car...proprietary! Goldmember runs MAF conversion with bigger injectors...works well and can be re-programmed.

BTW...I don't think STS actually has a patent on this "***-end" setup. I did the search over 18 months ago...nothing. I will look on USPTO.gov again to see if I can find it now. There is nothing to patent there, it is bull****. Corky Bell and Gerhard Schruf did this many years ago on NSX and Focus. Nothing to patent in my mind. But I have seen cleverly worded patents before...

I'm proud to report that I'm still running the Gold Knight 3-spd in the Goldmember with good results!

Tom. M

Tony,

That is exactly the way it is happening... Funny how that works eh?

Later,
Tom
midlman@rennlist.net
89GT

atb

Jyoon wrote:
>>>how are people managing fuel control in boosted cars, whether it be turbo or sc?

The rear turbo car is using nothing fancy at this point, just 30lb injectors, RRR, and SMT6.


Tony wrote:
>>>>>Have those guys up there in the PACNW thought about emailing or calling STSturbo for some input on a rear turbo application for a 928?


I believe they went to STS to get some baseline specs for their system. It was pretty far off, and they have ended basically enlarging everything from their prototype. I guess the 928's like to move more air than their detroit counterparts.

sublimate

A boosted stroker? It seems that limitations in the gearbox will show up before then. Perhaps someone will have done a Vet transaxle by then? Which brings up the question: Will you allow transplants in your big HP shootout? A 928 with a new 500hp LS7 mill? Hell, strokers already have Chevy pistons and rods.

Personally for me it's all about how the car drives and I could care less what it says on the valve covers.

Tom. M

While we are on the topic..just a few opinions of the system..

While every system has it's plusses and minuses...here are a few pluses of the rear turbo setup..:

It is relatively easy to implement, and uses space formerly taken up by the mongo rear muffler.
Preliminary dyno data is good and tweaks are forthcoming (right now about 100 rwhp over stock)
Inside the engine bay it removes the two air tubes and opens up the engine area for all to see in all its glory..(or as paint peeling oil covered mess.. haha).
Can go back to stock easily
The sound is awesome when the turbo spools....but somewhat odd coming from the back..haha...

I am awaiting final results...and may even consider putting on my GT.to see how much diff the GT cams would make...

Later,
Tom
midlman@rennlist.net
89GT

atb

Tom wrote:
>>>>>>I am awaiting final results...and may even consider putting on my GT.to see how much diff the GT cams would make...


Dude, we got the motor out, you want to reseal your GT cam covers anyway, SWAPPY TIME!

TAREK

Tony,

STS had a booth at a local "muscle car" show. One of their trucks was there too. The guys I spoke to were salesmen and full of BS. If it's not on their catalog, they know nothing about it. Even the knowledge of their own product on the applications they offer, was lacking....so it was disappointing. Oh well...I'll just have to stuff my turbos and Air/Air intercoolers under my mucho rear flares and let you know how it goes

Tom. M

haha...don't think that it hasn't crossed my mind

Oh...we won't be able to finish the engine refresh in time...but if you twist my arm I might offer up my car as a test bed..since I've got plenty of baseline dyno data..haha..

Later,
Tom
midlman@rennlist.net
89GT