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How to determine what the best shift extensions are for you?

Old Jul 16, 2003 | 08:31 PM
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Default How to determine what the best shift extensions are for you?

Ive got pretty much everything figured out that I want in my converter, but Im lacking where I want my shift extensions. To be honest, I really dont know what it is, but I was asked during a conversation discussing the converter. Im wanting to know where I should have them so that it can be built with it. Could you also explain a little what shift extension is? My car currently has all the bolt ons, C2 cam/valvetrain, and I will be doing 5.3L stage 1.5/2 heads later. Im not sure what all you need to know to determine where I should put them, but if you need to know what my car has and what it will have in the future, let me know and Ill break it down for ya! Thanks
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Old Jul 16, 2003 | 08:51 PM
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Default Re: How to determine what the best shift extensions are for you?

i too would be interested in this since i'm having a converter built very soon
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Old Jul 16, 2003 | 10:06 PM
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Default Re: How to determine what the best shift extensions are for you?

Shift extention means what RPM does the engine drop to on the gear changes. For example, my car has MTI stage 2 heads/cam, and with my PT 4200 converter the engine drops to 5700ish right after a shift. If you run all motor with cam or heads/cam you should choose a converter with a high shift extention for best ET. However, the higher shift extention converters will usually feel looser in a daily driving situation. The yank SS 3800 converter is supposed to have a shift extention around 4900-5000 and I hear it feels quite a bit tighter than my converter does. I can't really say how much because I have not been a car with that converter before.

Jordan
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Old Jul 16, 2003 | 10:28 PM
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Default Re: How to determine what the best shift extensions are for

I'd say somewhere in the 800 to 1200 rpm drop in between shifts at the rpm u shift at..

EG 6600 shift point drops to 5400 to 5800...
EG 6000 shift point drop to 4800 to 5200....

Thats a rule of thumb but one that seems to work well
for me and alot of guys I know that race.

JS
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Old Jul 16, 2003 | 11:19 PM
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Default Re: How to determine what the best shift extensions are for

Yup what JS said is correct. Unless the car is on the bottle, then you'll probably want a lower shift extension/shift recovery.
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Old Jul 17, 2003 | 01:29 PM
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Default Re: How to determine what the best shift extensions are for

As of right now with my 6-speed set up, the car redlines at 6700rpm, but I shift it at 6500rpm. Will converting to an auto have any play on where the shift points should be? If so, when I decide on my shift points, will it help me to figure out where I want my shift extensions? Ok...I understand what shift extensions are, but how do you determine where you want to set yours at? Does the shift extensions affect the gas mileage at all? I plan to do a bigger cam and 5.3L heads later down the line, will that affect where my shift extensions will be? Let me know if you need more info on my car to help me decide on where I want to put them. Thanks
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Old Jul 17, 2003 | 02:33 PM
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From: Jersey boy
Default Re: How to determine what the best shift extensions are for

if its 800-1200 fo a N/A car what would it be on a nitrous car? that is what i really want to set up this converter for
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Old Jul 18, 2003 | 01:57 AM
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Default Re: How to determine what the best shift extensions are for

if its 800-1200 fo a N/A car what would it be on a nitrous car? that is what i really want to set up this converter for

I would say for a car set up for the bottle on the motor you want to have between 1400 and 1800 on the shift recovery/extension. The Best N20 Converters seem to be the Yank 3600, and Tci 3500
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Old Jul 18, 2003 | 02:44 PM
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Default Re: How to determine what the best shift extensions are for

Where do you think that I should have them put at? All the bolt ons, cam/valvetrain, and stage 1.5/2 5.3L heads down the road. Ill probably be running a 3800 with a 2.5 or 2.6 str with 98% efficiency. Thanks
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Old Jul 18, 2003 | 03:19 PM
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From: Jersey boy
Default Re: How to determine what the best shift extensions are for

mustang eater: eveyone says it should be lower for nitrous. it seems your numbers go the other way . doesa bigger number for shift extention mean less like the way guages work(wire/gun guages not car guages).
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Old Jul 18, 2003 | 04:44 PM
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Default Re: How to determine what the best shift extensions are for

I dont get what you're asking. On a Heads Cam car with a TCI3500 on the motor you're looking at Recovering around 4800 w/ a 6600 shift point, at least mine does that. 6600-4800=1800. When you bottle the car the converter will flash higher won't it? So the shift recovery/extension will be higher.
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Old Jul 18, 2003 | 05:40 PM
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Default Re: How to determine what the best shift extensions are for

Derek said mine is supposed to be at 5800. Just talk to him about it, he will explain anything you need to know and even help your decision.
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