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velocity320 05-09-2011 04:39 PM

454 build horsepower?
 
I have a pretty standard build but just wanted to ask any of the motor guys how much horsepower and or reversion I might have with this setup before I finish it up.

454 .30 over balanced and shotpeened internals
L2399F speed pro forged pistions .095 dome height
comp roller cam and lifter setup xr284h-r12
Dart 308cc heads 2.25 int 1.88 exh
Edelbrock Rect. port air gap intake
Demon 825 carb
Dui distributors
Stainless Marine Gen 3 exhaust

I think it should have somewhere around 9.5 compression, but not sure on the horsepower. Also I was going to use stock ratio rockers, but would different ratio increase horsepower?

Thanks again for any input

getrdunn 05-09-2011 05:14 PM


Originally Posted by velocity320 (Post 3398740)
I have a pretty standard build but just wanted to ask any of the motor guys how much horsepower and or reversion I might have with this setup before I finish it up.

454 .30 over balanced and shotpeened internals
L2399F speed pro forged pistions .095 dome height
comp roller cam and lifter setup xr284h-r12
Dart 308cc heads 2.25 int 1.88 exh
Edelbrock Rect. port air gap intake
Demon 825 carb
Dui distributors
Stainless Marine Gen 3 exhaust

I think it should have somewhere around 9.5 compression, but not sure on the horsepower. Also I was going to use stock ratio rockers, but would different ratio increase horsepower?

Thanks again for any input

I had a very simular set up only with the Dart oval port heads (valako) worked. Actually this was back in my learning days of porting, Jim supervised and flowed. less the .030 over on the bore with 9.5/1 comp and was at 481 or 485 hp at 5,600. That was with dyno headers however on the boat I used lightenings. Holley 800 cfm/9022. I still have the sheets around here some where. Ran great and very dependaple. No issues with reversion and that was with the 502/465 mag cam (flat tappet) and think the ones I used were on a 110 ls and still no rev. This was back in 1993. Can't think of the grind right at the moment however it's all over here on the board.

picklenjim 05-09-2011 05:36 PM

My quess on hp would be about 475. I would have used a cam with a little more lift. Using 1.8 rockers would give you a little more lift. Assume your going to use roller rockers. Shouldn't have to worry about reversion.

cam specs
284/290
.547" I&E
112

pantera232 05-09-2011 05:38 PM

I have similar build Bob m told me 500hp with 781 heads, morel lifters, smarine exh, .6 lift cam, what size cam you going to run.

getrdunn 05-09-2011 06:03 PM

If your not going to dyno I would wait on the 1.8's. You can always add them later. You may see some or a little gain on the intakes and the 1.72 on the exh. Just my opinion and experience. post a cam card or specs when you can. It seems like that cam has + duration. You have a pretty good set up and looks like your on the right track. Did you take anything off your heads? I remember with the same comp and basic chambers as well as dome pistons I was getting close with intake valve piston clearance but you should be fine as long as you install cams/cam according to your card and don't advance.

velocity320 05-09-2011 06:07 PM

Thanks for the input guys, heres the cam card.

Cam Style Hydraulic roller tappet
Basic Operating RPM Range 2,200-5,800
Intake Duration at 050 inch Lift 230
Exhaust Duration at 050 inch Lift 236
Duration at 050 inch Lift 230 int./236 exh.
Advertised Intake Duration 284
Advertised Exhaust Duration 290
Advertised Duration 284 int./290 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.547 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.547 in.
Valve Lift with Factory Rocker Arm Ratio 0.547 int./0.547 exh.
Lobe Separation (degrees) 112

I was looking for around 475hp

velocity320 05-09-2011 06:10 PM

Nothing off the heads, bought everything new. The dart part number is 15100010, they come set up for 2.250 and 1.880. I had the lower ends for another project ready to go and bought all the upper end stuff so I could enjoy the summer. I have the gen 6 502s that were with the boat (1 had bad rod) when I bought it. Was thinking about bore and strokin for next summer.

getrdunn 05-09-2011 06:15 PM


Originally Posted by velocity320 (Post 3398791)
Nothing off the heads, bought everything new, I had the lower ends for another project ready to go and bought all the uppers so I could enjoy the summer. I have the gen 6 502s that were with the boat (1 had bad rod) when I bought it. Was thinking about bore and strokin for next summer.

You got, Go have fun. You have a very reliable good package there.


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