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454 500hp Build Question

 
YoungGunSTL
I love my Chevy Chevette!
Posts: 10
Joined: 03/14
Posted: 03/25/14 08:58 PM

Hey everybody, im looking to build another 454 for my 85 elcamino being that the exhaust shop blew my other one up. Ive been looking at the "454 500hp Budget Build" and have a question about my pistons. Will using the flat-top 2 valve relief pistons in my 1973 block, will i be able to run procomp oval ports the same camshaft that the build used? Im really trying replicate the build and am looking into just leaving the bottom end stock (just rebuild its with new seals and bearings) and just running some oval ports heads with big valves,a decent sized camshaft (around the .540 lift area) and dual plane intake with 850 holley dp. Is my build sounding like a 500hp area build? Im just thinking its going to be a dog at around 8.5:1 compression? Any Suggestions? thanks for your time. (btw transmission is th400 with 2500 stall and stage 2 internals)  

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tuffnuff
Moderator
Posts: 7841
Joined: 12/09
Posted: 03/25/14 09:36 PM

How much street time is the car going to see? If you're not looking at a lot of street driving, I'd look at getting a 3.73 for the rear gear.
The big ticket to getting budget power out of your 454 is compression ratio (9.5 to 1) would be a step in the right direction and of course a suitable cam. A good hydraulic roller will be your best option. But, just don't throw any cam at your motor. Get all your head specs together, then call one of the cam companies, tell them what you want to do, and ask for the best recommendation. More often than not, the best cam is not the biggest.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

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YoungGunSTL
I love my Chevy Chevette!
Posts: 10
Joined: 03/14
Posted: 03/25/14 10:14 PM

The car will be a weekend racer but see the street for the most part, but will not be daily driven by any means. Im looking to make good power but do not want to pull my bottom end apart if i could make good power with lower compression, the budget build article said the ran stock flat top 2 valve relief with procomp heads and still pulled 500hp out of it if im not mistaken. Just am trying to avoid ripping the already assembled bottom end back out to run a dome top piston. Thanks for the advice!  

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YoungGunSTL
I love my Chevy Chevette!
Posts: 10
Joined: 03/14
Posted: 03/25/14 10:32 PM

Oh and eventually the car will see either a grand national rear end or a 9 inch with 3.73 or 4.11 gear.  

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shyrgfuh3
V-6 Camaros rule!
Posts: 67
Joined: 01/14
Posted: 03/26/14 12:34 PM

hello,

procomp heads are chinese ans flow poorly so take your chances. if you buy them you should get them ported.

you can make "decent" power at 8.5 but as tuffnuff mentioned, 9.5 is better.

if you have stock rods, stock rod bolts and stock type cast pistons and stock cast crank i would not build it over around 350 hp.

milling heads .028" from stock will increase your compression by .4 without causing intake fitment problems.

since the procomps are chinese, you would have to place them on them and the intake on the engine and "guestimate" how much you can safely remove.

there is no such thing as cheap RELIABLE horsepower.  

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YoungGunSTL
I love my Chevy Chevette!
Posts: 10
Joined: 03/14
Posted: 03/26/14 03:46 PM

Should i look into a set of 840 heads? The guy who is selling them is telling me i can get at least 10:1 with flat tops with these heads, They have extensive port work and the large 2.30 and 1.88 valves and he's only asking for 1000 dollars, and they come with new .650 lift roller springs, If i went that route i would buy a roller retro cam kit. Motor has a steel crank and dimple rods. With those heads and a decent roller cam it should be easy to make my hp goal right? But is that bottom end going to hold up?  

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YoungGunSTL
I love my Chevy Chevette!
Posts: 10
Joined: 03/14
Posted: 03/26/14 03:47 PM

Should i look into a set of 840 heads? The guy who is selling them is telling me i can get at least 10:1 with flat tops with these heads, They have extensive port work and the large 2.30 and 1.88 valves and he's only asking for 1000 dollars, and they come with new .650 lift roller springs, If i went that route i would buy a roller retro cam kit. Motor has a steel crank and dimple rods. With those heads and a decent roller cam it should be easy to make my hp goal right? But is that bottom end going to hold up?  

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shyrgfuh3
V-6 Camaros rule!
Posts: 67
Joined: 01/14
Posted: 03/27/14 02:55 PM

well those heads are 109 cc which will get you only 8.25 static comp on a .030 over engine with flat top pistons.

the porting might be good or might be a hack job.

you need to see how much the heads have been milled. if it is more than around .035" you might have intake fitment problems.  

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shyrgfuh3
V-6 Camaros rule!
Posts: 67
Joined: 01/14
Posted: 03/27/14 03:08 PM

well those heads are 109 cc which will get you only 8.25 static comp on a .030 over engine with flat top pistons.

the porting might be good or might be a hack job.

you need to see how much the heads have been milled. if it is more than around .035" you might have intake fitment problems.

206, 702, 390, 802, 215 heads then mill them .023 from stock.

94 cc chambers will get you 9.2 compression. this is enough on a 454

i mentioned what you i think you should do to your bottom end for 500 hp.  

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Dave632
I mow my lawn and find Chevys
Posts: 2253
Joined: 07/08
Posted: 03/28/14 05:42 PM

The stock BB bottom end is pretty good and it will hold up pretty well under mild power increases. This is why it is such a staple in drag racing. It has been around for almost 50 years now and there are many of them still out there fighting the drag wars. I think it would hold up OK with about 500hp as long as you keep the revs in the 6000 and under category. There are no guarantees in racing however and I have seen high dollar setups go bad in my time.
I am not familiar with the build you are talking about but I would surely listen to tuffnuff when building a BB in this way as he has experience in building stock headed oval port BBs and getting over 500hp out of them with heavy porting. PM him for some more information it will help you a lot.
My experience is with much crazier stuff and I was able to get little out of stock oval port heads but I gave them little chance as I dumped them after one trip to the track. My CRs were in the 14 to 15-1 range running little 600+ inch motors.  
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