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More power and torque for my ‘96 Chev 454

Posted: Tue Aug 31, 2021 8:36 pm
by Dknister
Hi folks. I just purchased a 1996 Fleetwood Southwind that has the 7.4 454 Vortec. It’s a 36-foot, 21000 lb rig and I plan to tow so looking for ideas on how best to boost low end torque. I’ve read a ton on these engines in larger motorhomes and the constant back and forth of diesel vs gas in larger motorhomes. My budget doesn’t support diesel and I’m pretty sure there are some relatively inexpensive upgrades I can make to increase power and torque.
We live in Alberta, Canada and have family in BC so some of our RVing will involve driving in the mountains. And like I said, we want to tow a small vehicle.
From what I’ve been able to find, the 7.4 Vortec cranked out about 290hp and ~410 ft-lb. I’m looking for what can be done to increase that to help out with climbing those mountains and/or towing my toad. I’m not a mechanic, but have some knowledge of engines. Any advice would be greatly appreciated. Would like to see what is the simplest cheapest thing(s) I could do and then some of the more expensive. Basically, what’s the best bang for the buck in terms of providing some decent power-torque increases. Thanks in advance. Darrell K

Re: More power and torque for my ‘96 Chev 454

Posted: Fri Sep 03, 2021 8:18 am
by Truckedup
That 454 should have factory forged 8-1 compression pistons.. perfect for a moderate boost supercharger. Not really inexpensive but may be the best choice...

Re: More power and torque for my ‘96 Chev 454

Posted: Thu Sep 09, 2021 10:17 am
by 408swinger
I would move this to the engine tech forum . You will get many more responses.
I am eager to read the input as I have a Dodge RV with a 440 that I would like to enhance.

The trick is making power mods that will live under constant load .

Re: More power and torque for my ‘96 Chev 454

Posted: Thu Sep 09, 2021 12:38 pm
by In-Tech
I've got one finished up on the engine stand . We went a little crazier on the build though. Ditched the junker preignition L29 heads in lieu of some alum brodix I had laying around , stroked it to a 496, used a long runner mercury marine intake manifold, custom cam, etc etc. All in the hunt for torque and fuel economy. I'm not looking forward to how long it will take me to "fix" the calibration in the old black box pcm but oh well, pretty good bud of mine. =D>

Best bang for the buck is a cam change and work over the heads(will require pcm tuning), pay special attention to the heart shaped chamber and lay it back a bit to keep that "glow plug" chamber in check.

Re: More power and torque for my ‘96 Chev 454

Posted: Thu Sep 09, 2021 11:50 pm
by Racer71
If you’re referencing the 4plug black box pcm you can swap to 0411 pcm easily which is much more tuneable. That would also allow you to convert to speed density if desired. The pins are the same just have to swap them into the 411 connector in the appropriate places and flash as a 3500 454 express van then tune away via hptuners etc.

Re: More power and torque for my ‘96 Chev 454

Posted: Fri Sep 10, 2021 1:12 am
by In-Tech
The black box is no problem. I have GM software =D> Thanks for the reply though.