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What to expect out of a 496 CI

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Old 03-31-2009, 09:26 PM
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Default What to expect out of a 496 CI

Just wondering what respectable but yet conservative number you can get out of a 496. I have been contiplating on stroking my 454's. I have always been able to achieve pretty good numbers and reliability from 454 rebuilds in the past however I was thinking of taking them to the next level. Reaching near 530 ft pds of trq and 500 HP at 5500rpm with 454/468's.
What would you think to expect with a 496 without going crazy. I'm ready to hang my rods and pistons to complete the short block and then I had a brain fart.

Any help with the project would be great so I can get moving here.

thanks,
John
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Old 03-31-2009, 09:45 PM
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:with everything else same as before,i think gains of 50 hp and 70 tq sounds right.this is a good question for dean,ray or tyler,ihope they post a reply on this.
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Old 03-31-2009, 09:49 PM
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500hp max


After that call your padre.
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Old 03-31-2009, 10:01 PM
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Hmmmmmm. Really
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Old 03-31-2009, 10:06 PM
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It all depends. What exhaust, heads, cam, intake. The only thing I would do different when I built mine was different heads. I used Edelbrock 290cc. Other than that I spared no expense best of everything. Like said above, just adding 42 cubic inches I would be surprised to see 50hp.

It reminds me of my first V8 boating engine I built, swamped the 305 228HP to a built 350. That shows my age
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Old 03-31-2009, 10:34 PM
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Default RE: 454 upgrades

Thanks for the reply.

new question is:

with all the proper engine components such as solid bottom end, recommended intake - dart?, Perf. RPM Airgap?, holley 800 cfm., Say something similar to the 168731 cam - rmbuilder spec., Roller rockers, 9.5 to 1 comp. and gill exhaust. Parts for a 496 what to expect on the conserv. side as far as trq. and HP.
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Old 03-31-2009, 11:10 PM
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The heads being used at this time are the worked over 049 casting's oval port 2.19's and 1.85's by Valako. We get these things to flow well and considering were under 500 CI and staying under 610 to 615 lift they will work fine. I used many of the dart recs and use to wedge them at this CI. Trq. and dyno results are amazing.

This is kind of a quick fix for this year. Next year I have decided to go to the 572's

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Old 03-31-2009, 11:57 PM
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Quote:
Originally Posted by getrdunn View Post
Just wondering what respectable but yet conservative number you can get out of a 496. I have been contiplating on stroking my 454's. I have always been able to achieve pretty good numbers and reliability from 454 rebuilds in the past however I was thinking of taking them to the next level. Reaching near 530 ft pds of trq and 500 HP at 5500rpm with 454/468's.
What would you think to expect with a 496 without going crazy. I'm ready to hang my rods and pistons to complete the short block and then I had a brain fart.

Any help with the project would be great so I can get moving here.

thanks,
John

Without going crazy and having a reliable piece that can run on pump gas, you can expect about 1.20 hp/ci with aluminum heads and about 9.5:1 compression. With a little more compression and a decent size cam, you could expect to see 1.27-1.29 hp/ci. Hope this helps, Eddie
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Old 04-01-2009, 12:43 AM
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Quote:
Originally Posted by Young Performance View Post
Without going crazy and having a reliable piece that can run on pump gas, you can expect about 1.20 hp/ci with aluminum heads and about 9.5:1 compression. With a little more compression and a decent size cam, you could expect to see 1.27-1.29 hp/ci. Hope this helps, Eddie
496 times 1.20=595.2.thats nice.eddie ,thanks ,thats just about what i figured.
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Old 04-01-2009, 12:49 AM
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Quote:
Originally Posted by getrdunn View Post
The heads being used at this time are the worked over 049 casting's oval port 2.19's and 1.85's by Valako. We get these things to flow well and considering were under 500 CI and staying under 610 to 615 lift they will work fine. I used many of the dart recs and use to wedge them at this CI. Trq. and dyno results are amazing.

This is kind of a quick fix for this year. Next year I have decided to go to the 572's
If you're keeping those heads, then I'd just leave it as a 468. I'd guess that you'd only gain about 30hp/40tq by stroking it with all other things the same. Not worth it, especially if you're gonna go to bigger power next year.
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