Looking at that dyno chart....

Shows torque down 50 at 2500rpm, you'd definitely MISS that much! (at least in daily driving). Now if this were a race/track car, fine. But I'm driving on the street more that anything. This setup is less and less appealing.

 

You'd lose too much potential exhaust energy if you did that... have the 2 tubes merge just before the turbo.

 

That's my whole point... also, looking at this again... why does low end HP & torque actually DROP below 3300 RPM at 7 PSI, compared to 5psi? Very odd...

 

That's what I meant, but didn't say.

The headers/manifolds would go into a 'Y' then back out to two pipes (one with a valve). Then merge together again at the turbo.

 

Perhaps there's another modification that isn't listed (between the 5 & 7 runs). It shouldn't drop at all.

 

Typically when you go from a 5 psi maximum boost to a 7 psi you are using a different turbo and contrary to public opinion the turbo restriction of the exhaust by forcing it to spin a turbine does cost energy. The larger turbos for higher boost tend to have more lag and require more energy to spin. Turbo chargers can only be efficient over a limited range of RPM ,you choose the RPM

 

just got off the phone with tech at STS and they stated that the numbers below 2500 on that graph are an anomally for some reason. They stated that there is no loss/change in driveability around town and that before the turbo starts to boost, you can't even tell that you have a turbo installed. This is also my experience with the GN. Around town it feels like a normally aspirated 6 cylinder until you get on it and then you can tell there is something special.

Also, in regards to off the line turbo lag, on an automatic this is a non- issue, powerbrake and hold and be prepared to hold on.

My brakes can hold about 5 PSI before they break loose.

Also tech told me they sell a kit with turbo, oiling system, waste gate and aircleaner for $2125. That would leave fabbing the intake.

 

Also the kinetic energy (heat) that the turbo absorbs from the exhaust gases can be no greater then the exhaust pipes in the same location absorb. The only diff. would be the heat sinking ability of the turbo. Ie... it would take langer to heat up and cool off then an exhaust pipe. Also, a fairly simple way to counteract turbo lag, even on a huge ceramic ball bearing turbo, is to increase the stall of the converter (auto.)

Obviously putting a honking huge turbo on a 3400-3800 stall converter will work, but you wouldn't want to drive the car except at the strip

 

nuc,

Thanks for the info!
...

So all I need do is develop my variable cam timing system, variable exhaust gas speed system, and then bolt one of these puppies on for the icing on the cake!

 

Sorry, they also said they include the wiring harness in that price.

 

nuc, did they point you to an anomaly-free chart? Also the mods you describe are not applicable to my 5 speed. One other thing... as Jim points out, it costs energy to spin a turbo. I'm very skeptical of the claim that there is NO impact on driveability.

 

But what turbo are they using for the LS1/whatever the camaro has in it engine? I think a t3 with an a/r of .46 would be fine, spool quick, boost aplenty! (for the smaller 928 engines).

Any input from the other turbo guys here?

Just waiting for John Kuhn to chime in here. C'MON JOHN!!!! ::

 

Sharkskin, the guy that I spoke with wasn't aware of the exact chart that I was describing from the site. He was a tech, probably not the owner or web guy. He just stated that there has not been any noticeable difference in driving experience with no boost and turbo or not having the system at all. He said that the chart seems to be an anomally. At a 50 HP reduction driving around town the LS1 guys would be screaming about the loss of torque and HP. I also cannot tell the diff. between driving a NA 6 cyl. Regal and then driving my GN (enginewise) around town until I get on it.

Seems like somebody should hop onto a few camaro boards and find out driver's experiences.

Also, in regards to your particular car, a 5 speed can also easily use a turbo with no lag off the line. You just need to use the parking brake to build boost while you let out the clutch. Also, in order to prevent overboosting and bending the turbine shaft on a manual trans car, you need a blow-off valve, whereas on an automatic it is overkill.

HTH

 

I really don't think you guys have any idea what you're talking about. Ask yourselves this: when you are out driving, how often is your tach indicating below 2400 RPM?

If you do like cruising around town at 2000 RPM, then based upon your driving style, it would make sense to NOT get any power-adder since you'll just be lugging the engine anyway.

 

Not a chance. Thanks for the input but I'm beginning to see that we have some very different views as to what a 928 can or should be.