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Torque Curve Dyno comparison: turbo vs Centrifugal

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Old 11-29-2005, 12:53 PM
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MarkRobinson
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Default Torque Curve Dyno comparison: turbo vs Centrifugal

I plan to put this on my site since the "word" remains all about the torque.

I plan to hit hte dyno this sat. with my corrected intercooler end-tanks: I had welded my inlets up with 2" pipe, thinking (at the time) that 2" was my limit under the car, but since even 2" doesn't fit and I/ve moved all my plumbing into the engine bay, 2.25" is a better fit & a bet less restrictive. So, I have a huge turbulent area where my 2.25" has to step down to 2" (12% reduction in area not to mention the turbulence/velocity choke), but even so, the HP/TQ increase is very apparent.
Old 11-29-2005, 01:00 PM
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MarkRobinson
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Forgot to mention since I'm sure someone will bring this to my attention: the outlet of the turbocharger is less than 2" ID (outlet is 2" OD), so keeping the piping small (2" ID) does not affect the "restriction" of the plumbing, & keeps the overall volume down so that spool is quicker.
Old 11-29-2005, 01:07 PM
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drnick
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mark, is there any way to shift that tourque curve further to the right?
Old 11-29-2005, 01:10 PM
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mulik51
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I am in no way guru in this stuff, but what if you increase the psi, won't the graph shift to the right. It is observable on SC runs, 5 psi vs 6 psi...

Just a thought...
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Old 11-29-2005, 01:12 PM
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Tony
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If i didnt have the TS on my car already i would consider being an S4 guinea pig .
Looks good Mark, nice comparison charts.

Actually i already have a manifold with an intercooler in it! Pretty simple fabrication for a small chamber to mount the TB and MAF to...all id have to do then is hook the pipe from your turbo set up to it!
Old 11-29-2005, 01:24 PM
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PorKen
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drnick,

Retard the cam timing?
Old 11-29-2005, 01:34 PM
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yeah porken, im already thinking this... the GTS has just got big lumps of midrange tourque already (maybe not as much as the forced induction crowd) which is really fun, but id like to see it shifted right. might do a search on cam timing to see how far this has already been taken.
Old 11-29-2005, 01:36 PM
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heinrich
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Well that's interesting. Shane's torque curve is very very flat.
Old 11-29-2005, 01:44 PM
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BC
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Do we have a Dyno graph to overlay from a 6 or 7psi kit from one of the current CS sellers? ON a 5.0, 32V?

Many of those guys are already at 10, 11 and 13psi safely, so I'm not sure how many are left, so...
Old 11-29-2005, 01:53 PM
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Not yet tuned dyno from 90 GT TS
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Old 11-29-2005, 02:04 PM
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Shane
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Originally Posted by heinrich
Well that's interesting. Shane's torque curve is very very flat.

Huh?
Old 11-29-2005, 02:06 PM
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Tony
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In the time between my post above, i fired up my $99 turbo cad and edited some of the things i had rendered already.
That is to scale to the nats *** as well.
Very doable!!

Actually i think the MAF on your system is prior to the Turbo inlet , correct Mark?
If so , easier..... even more room in the engine bay!!
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Old 11-29-2005, 02:13 PM
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Tony,

I just gotta say I wish I had 1/2 the energy and know how that you have.
Cool drawings

edited
oops, wrong thread...
I agree, there should be plenty of boostards in Denver.
There's always next year for the haircut and bath.



Originally Posted by Tony
In the time between my post above, i fired up my $99 turbo cad and edited some of the things i had rendered already.
That is to scale to the nats *** as well.
Very doable!!

Actually i think the MAF on your system is prior to the Turbo inlet , correct Mark?
If so , easier..... even more room in the engine bay!!

Last edited by Jim_H; 11-29-2005 at 02:25 PM. Reason: wrong thread
Old 11-29-2005, 03:03 PM
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Originally Posted by Shane
Huh?
Well it was, when Heidi had one
Old 11-29-2005, 03:23 PM
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You could shift the torque curve to the right by using a .96 AR turbine housing on the turbo...will make things happen about 500rpm later.. Though on a GTS, I'd think it would just lengthen the curve to the right & not simply move it over.


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