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Robert Palmer 07-13-2009 09:44 PM

Shift Points
So I have a question about shift points.

What would be the highest shift point for the 5.7 HEMI on 1-2 and 2-3, that makes power and I am not spinning the revs for no reason?



Marlin 07-15-2009 08:43 PM

Re: Shift Points
Joe, best thing I could suggest is look up the factory rpm specs for your hemi.

Best performance will typically come from shifting at the peak POWER rpm.
On the shift that will typically bring the rpm back to somewhere around the peak TORQUE.

Get me???

Robert Palmer 07-15-2009 08:48 PM

Re: Shift Points
Ok Ben. Here is my 1-2 shift:

Here's the chart:

What do you think?

Marlin 07-15-2009 09:03 PM

Re: Shift Points
dont see the chart?

Robert Palmer 07-15-2009 09:12 PM

Re: Shift Points

Here you go.

Marlin 07-15-2009 09:27 PM

Re: Shift Points
I'm not a member mate..... so i cant see it.

---------- Post added at 12:27 PM ---------- Previous post was at 12:27 PM ----------

Anyway, just tell me peak power and torque rpm

Robert Palmer 07-15-2009 09:31 PM

Re: Shift Points

Scottina06 07-15-2009 09:59 PM

Re: Shift Points
wasting your time bro unless you got the mods to support it...told you this on the phone....LOL

Marlin 07-15-2009 10:04 PM

Re: Shift Points
Well, I'd shift up at 5600/5700, judging by the vid that should bring it back to around 4k in 2nd gear, right at the peak of torque.

But do you have a custom tune? Things will change dramatically with one, these hemis run ridiculously rich at WOT.

Robert Palmer 07-15-2009 10:06 PM

Re: Shift Points
I have the Canned 93 Diablo Tune.

What would you suggest Ben?

blackpepper 07-15-2009 10:10 PM

Re: Shift Points
Rich at WOT?

See Joe, 2% is too much up at the higher RPMs... bring it back down to neutral or make it run lean by no more than a percent.

Marlin 07-16-2009 01:11 AM

Re: Shift Points
A canned tune is ok, but you'll ALWAYS get much larger benefits from a dedicated tune by a good operator on a dyno. Yep, take it to a good dyno tuner who can tune Diablo, and have them strap it to their dyno and tune it. It's not cheap (think $500), but real gains never are.

Maybe DynoSteve can help you? He's an Aussie ex pat now stateside, quite experienced with these. He dyno'd a 5.7 in a 300C with the factory tune while I was in the dyno cell, and I was astounded to see air/fuel ratios approching 8:1 at WOT high RPM. Those kind of numbers are ridiculous! As you know stoich is about 14:1. Obviously Chrysler runs them so rich to allow for every ounce of abuse that someone could dish out. That's why I've said before, clean up that fuel map, and there's ALOT of power to be had.
Now, my humble opinion is the canned tunes DO give you an improvement, but very slight given they also want to keep a large margin for all types of abuse. They dont want internet word spreading that an engine running their canned tune blew up (even though the guy might have been doing donuts in sand dunes for 3 hours before it finally cried enough).

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