Converter question.
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9 Second Club NA
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From: Houston, TX
Converter question. Ok...lets say a converter has a shift extension of 5500 rpms, what kind of range should it have between shift points and the shift extension? For example, a converter should have at least 500 rpms between the shift extension and the actual shift point. I really dont know how to word this question, so Im trying my best to make it clear. Another example, obviously you dont want the shift extension and shift points to be too close, 5500 shift extension with a 5700 shift point. With that example, youll be going through the gears really quick hurting your times. How long do you wanna stay in the gear? I havent tried out my converter yet to see what kind of shift extension it has because it keeps hitting the rev limiter, but what Im looking for is, how much range should there be between the shift extension and the actual shift point. Does that make sense? Then lets look at the other way, you wouldnt want a converter that has a 5500 shift extension if you have 7500 rpm shift points because there is too much gap. Im only assuming. Anyhow, hopefully Ive worded my questions right and provided enough info for an answer. 
Thanks.
Thanks. 
I would look for around 600 - 1000 rpm if I were trying to optimze it and had a converter properly designed for a long extension. Normally peak HP flattens out a couple hundred rpm before peak. You don't want your shift extension to go past peak HP. IMO, you want to stay close to peak HP for as long as possible. For example, if your shift extension lands 300 rpm before peak and you shift 500 rpm past peak, you'll have a spread of 800 rpm. With the right converter, you'll have excellent MPH with a converter designed like that.
BTW, the tradeoff for an optimized shift extension may be a sub-optimal stall speed. The incorrect stall speed would hurt you more at the track then you would gain from the shift extension.
BTW, the tradeoff for an optimized shift extension may be a sub-optimal stall speed. The incorrect stall speed would hurt you more at the track then you would gain from the shift extension.
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9 Second Club NA
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From: Houston, TX
Im in the process of looking for a cam, but if I find a cam that peaks around 6400 and I shift the car at 6600 rpms, I would want the shift extension to be around 5800 for a range of 800 rpms. If that is a optimized set up, then that would be perfect because I think the PT4400 has a shift extension of around 5700-5900. More than likely I wanna find a cam that peaks around 6300-6400 because Im going to have 6600 shift points. I never looked into this when choosing what converter I wanted to go to from the SS4000 I had. I just went with the PT4400 because everyone said and proved that it was the best performing naturally aspirated converter. So it may look like I chose the right one coinsidently.
Thread Starter
9 Second Club NA
iTrader: (180)
Joined: Mar 2003
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From: Houston, TX
So do I have the right idea above?
Also...
Could you explain more on the above quote? Thanks.
Also...
BTW, the tradeoff for an optimized shift extension may be a sub-optimal stall speed. The incorrect stall speed would hurt you more at the track then you would gain from the shift extension.
