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Discussion Starter · #1 ·
Hi all,

Long time lurker, first time poster. I'm trying to prop my new Chaparral. It's a '95 2130SS, and I need to know what the optimum RPM range and HP is for the stock carb'd 454 that's in it.

Thanks!
Shane
 

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Should be a tag on the valve cover also stating MAX rpm range. If you haven't already checked that, I know they usually don't state HP though. I have heard differing stories as to HP ratings. My 7.4, I been told, was 330 at flywheel, 300 props (Bravo 3). 4800 was shown as mx rpm there too. Welcome also!
 

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If it's a 454 mag the prop shaft hp is 385.The max RPM is 4900 at least this is what my brothers 1997 Baja Hammer is rated.
 

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for a standard 7.4L in 1995, hp is actually 300 or 310hp (dont know why some are different) at flywheel (peanut port heads) rpm 4200-4400 , its the weakest of the bunch , probably 270 at the prop , I know , I have that very one and it has the specs right on the engine tag.
 

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Discussion Starter · #7 ·
HTRDLNCN said:
for a standard 7.4L in 1995, hp is actually 300 or 310hp (dont know why some are different) at flywheel (peanut port heads) rpm 4200-4400 , its the weakest of the bunch , probably 270 at the prop , I know , I have that very one and it has the specs right on the engine tag.

Hmmm, so if I do have that one, then the 15.25x19P hitting 4700 RPM's is over revving the motor a little. I'm going to pull serial #'s tonight and get verification for sure.


Thanks! (Though it kind of sucks I might have the "dog" of the 7.4L world...)
 

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I have tried a 22p Bravo1 prop, a 23P Rev4 and a 21pMirage and a labbed 24p Bravo1 and so far the best all around has been the labbed 24, gets on plane easily and runs [email protected], at least it did till I blew up the 454..
:(
Once I have the money I will be fixing it and swapping the peanut port heads and intake for large port ovals and an Ebrock rpm intake.
It will add a bit of hp (30-40?) but even better really improves the rpm range because the heads are no longer choking the engine.
Even with the same cam what I have read posted are gains of 4-5mph with just the heads and intake.
 
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