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Discussion Starter #1
Run was made on a dynojet. Pump/race fuel mixture of 5gal/12gal. Pulled TRAC fuse,
overdrive off, outside temp. was around 82 degree F.

My mods are below in the sig. Set the boost
limit to 1.25 bar. The dyno tech could not
figure out where to put the RPM sensor so
my run was for HP only, so my power is power
curve is plotted as HP vs. Speed.

Brought the car slowly up to 3rd gear and at 60 MPH, I floored it all the way to redline
for both runs.

First run, DSBC ratio=65,gain=5 max. boost
hit 1.07bar(~15.4psi)and only 261 RWHP.

Second run, DSBC ratio=72,gain=5 max. boost
hit 1.09bar(15.7psi) and only 268 RWHP. WTF!

I can routinely hit my 1.2 bar boost limit on the street with ratio=72.

When I look at both curves, I let off at redline and the dyno was only registering
125mph!!! When I floored it at 60mph both
curves show the power coming on, at 80mph the
car is making 240HP, but then the power abruptly drops by about 25HP, and the curve after that is alot flatter. Max. HP is only at around 105 mph.

On my way home, I could hit 1.2bar and did
not hear any death whine.

What the heck is going :confused: :confused:
 
Z

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OUCH! :eek:

sorry to hear that...I know what you are going through, my first dyno had almost exact #s as yours.

first, even with fan blowing at your FMIC, your car is not getting enough air which means lower boost. and where is your cone air intake?

The place I went dyno is ran by some redneck machnics who has no idea about our sophisticated japanease car, took him about 30 min to hook the wire up for torque measuement...where did you go?

when I dynoed my, I has a fuel leak and boost leak which only pushed o.7 bar with my AVCR set at 1.5. Cant explain the sudden drop of 25hp though, timing retard shouldnt take away that much, on mine the power curve just looked very jagged. most likely its from the actuators opening up just before the #2 turbo kicks in if you are in sequential mode.

However, with car pushing 1.0 260 is still a bit low. If I were you I would check the engine compression right away, dont worry about your turbo cuz as long as the boostgauge is reading 1.2, than your engine is getting 1.2 bar of boost no matter what the condition of the turbo is.

Another thing to consider could be your clutch. did you notice any slippage during high gear pull?

Jonas
 

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Discussion Starter #3
I went to the closest shop around my area at
The Dyno [email protected] Mustang Ranch.

That HP drop at 80mph was either the car downshifted or that was the 2nd turbo
transition.

I did not notice the any slippage near the end of the run but the curve from 100 to 125
was just undulating by about 5~10HP.

Max HP just topped out 100mph.

I'll have the compression checked Monday.

Thanks

[ June 24, 2001: Message edited by: booster ]
 
Z

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could be the compression...if not, an overheated engine running with lots of timing retard.
where you gonna get it tested? near San jose?
I am thinking of doing one to my TT also, maybe we can get it done together?

let me know

Jonas
 
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was it staying in third? or downshifting to a lower gear? did you have the MANU button selected? you have pretty much the same setup as me and i put down 400rwhp a couple months ago... i'd be inclined to say your car was fine, it just kicked down to 2nd gear and you were dynoing in 2nd.
 
Z

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can auto ake 80mph in 2nd? I am not familiar with supra auto tranny, but if the manual botton is pushed, shouldnt it be only downshifting 1 gear only to 3rd?
 

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Discussion Starter #7
Originally posted by NOVAsupra:
<STRONG>was it staying in third? or downshifting to a lower gear? did you have the MANU button selected? you have pretty much the same setup as me and i put down 400rwhp a couple months ago... i'd be inclined to say your car was fine, it just kicked down to 2nd gear and you were dynoing in 2nd.</STRONG>
I really did not notice/feel the car downshift, I know the car was in 3rd gear
at 60mph because I counted the shifts and I
felt them as I slowly brought it up to 60pmh.
The power curve from 60 to 80, when I stomped the gas looks like it is on Viagra. But when
that 25HP drop occured at 80mph, the curve
after that looks like it got doused with ice
cold water.

If the car did downshift to 2nd at 80mph, why
did it not shift back to 3rd for the rest of
the run?

Will MANU mode still work with the TRAC fuse pulled? It would like to try another dyno run
but this time with MANU mode in 3rd gear. Is
this reasonable?

Thanks
 

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i have heard from b4, that the manu mode does not work when u have the trac fuse pulled...hope that helps some
kev
 
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