Are my RPMs going to high for making max power?
05-20-2003, 04:01 PM
#1
TECH Apprentice
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Are my RPMs going to high for making max power? Not sure where I should post this, but Ill ask it here.. I have always had my shift points at 6300 on my stock internal 98 A4. According to my tach it shifts ~6500, but I have read that the tachs can be off.. I had a ST3500 converter and the RPMS would fall to about 5 grand or so and then climb again. Well I went to a different converter now. I went to a TP4500 stall.. Now my shift is at the same spot but the RPMS are only falling to like the 6000 range according to my tach. 2nd gear doesnt seem near as strong as what it used to seem... Do you think Im overthrowing my powerband of the stock cam... Im thinking about lowering my shift points down some and maybe it will fall lower after the shift instead of keeping it so high..
Let me know what you guys think about the RPM issue with stock cam....
Thanks
Let me know what you guys think about the RPM issue with stock cam....
Thanks
05-20-2003, 09:46 PM
#2
Launching!
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Re: Are my RPMs going to high for making max power? I think the easiest way to see if you're winding too high on your shifts would be to consult a dyno--then you'd be able to see your powerband and could make a more educated decision as to where to shift to maximize your power...
05-20-2003, 10:05 PM
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Re: Are my RPMs going to high for making max power? just curious, but y did u take out the st3500?? people r running 10's with that converter... i do think ur keeping ur car out of its power band with that 4500... u should be shifting at 6000 with a stock cam, plus the stock springs will not take much more than that... i bet ur getting valve float from spinning the motor that high on the stock springs...
05-20-2003, 11:44 PM
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D(irecto)r Pepper
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Re: Are my RPMs going to high for making max power? The stock tach sucks. At WOT it is at least 300 rpm off.
The TP4200 is a superior race verter than the ST3500. With that said... if you have a heavy car I would run the ST and if your car is set up for the strip...light, and made to run, the TP should pull it in the mid range and the top end.
Now are your RPM's too high? First of all with the stock tach you have no idea what RPM's you are running.
Borrow a buds atou tap and make a few runs and see where it is shifting.
...best idea? go to the track. Make three runs and get a baseline. Then adjust the shift points up 100 rpms and try it again for three runs.
Keep raising or lowering the shift points until you get your best times.
Launch the same, burn out the same, use the same lane etc... the only change should be the shift points.
Good luck.
For what it's worth when i was stock i shifted at 6500~6600.
Later.
The TP4200 is a superior race verter than the ST3500. With that said... if you have a heavy car I would run the ST and if your car is set up for the strip...light, and made to run, the TP should pull it in the mid range and the top end.
Now are your RPM's too high? First of all with the stock tach you have no idea what RPM's you are running.
Borrow a buds atou tap and make a few runs and see where it is shifting.
...best idea? go to the track. Make three runs and get a baseline. Then adjust the shift points up 100 rpms and try it again for three runs.
Keep raising or lowering the shift points until you get your best times.
Launch the same, burn out the same, use the same lane etc... the only change should be the shift points.
Good luck.
For what it's worth when i was stock i shifted at 6500~6600.
Later.
