Re: 200Q: Ruminations on low-end torque

["Linus D. Toy" <linust@interramp.com>]

At 08:57 PM 3/11/96 -0800, you wrote:

>On Mon, 11 Mar 1996, Arun Rao wrote:
>DELETED:  question about torque in the 20v turbos...
>
>I believe that thread was about the S2/S4/S6 motor.  I don't know if the 
>figures are the same/similar for the 200's motor.  Also, that figure is 
>true, but with the turbo already spun up, not from a dead stop.  It 
>should be higher if you don't spin the turbo first.

the '91 200q engine is quite similar to the S4/S6 engine.  minor differences
include distributorless ignition and a limited overboost condition that gets
it a bit more hp/torque.  however, the intake tract is much more convoluted,
crossing over from the right side to the left side, with some *long* pipes.
peak torque on the '91 200q is also at 1950 rpm

 tdonohue@xnet.com (Terry Donohue) adds:

>This always bothered me too, because the low end torque of our turbos is
>generally useless.  However, the specifications are correct, but only in
>the dyno lab.  
>[DELETE:  dyno lab rating method description].
>So these output numbers, while technically correct, are truly misleading
>in the real world.  If you want to confirm full boost at low RPM in your
>car, put it in 5th (or 4th) at 2000, give it full throttle, and also apply
>enough brake to keep it at that constant speed-you will slowly see the
>boost rise (and I mean slowly) before either your brakes or your
>determination gives out.

On the 20v turbos, you're more likely to see peak torque (1.8 bar stock) if
you start at 1500 rpm going up a slight hill.  And while it might take a
bit, I typically see 1.6 or 1.7 bar within a couple seconds--1.8 does take
longer, but 1.7 ain't bad!  btw Terry, your sig doesn't say--do you have a
'91 200q or other year?  don't know how the boost rises in the 10v turbos.

your comment on real world, though, is interesting.  only in the US where we
play in the stop-light drags does the off-the-line grunt of the turbos put
us at a disadvantage.  on the freeway, even in non-boost mode, flooring the
gas pedal has a strong effect--and if you want more, just downshift!

linus
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* linus toy           email:  linust@interramp.com                   *
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