H.O motor question

[PowerSlideGT]

Hey guys, Please help me, give me an estimation on how much horse power this motor would have.

H.O 302 Bored 40 over
flat top pistions
Roller cam 380 lift
Roller rockers
gt-40 manifold
202 roush heads, double springs
Balanced and blue printed
headmen headers
H pipe
3.73 gears
tremec world class tranny

Just curious. Thanks

[tireburner163]

I think you've got the cam wrong. Stock lift is .444 lift. We need to know the duration @.050 on the intake and exhaust side, and the lift

Are the roller rockers 1.6 or 1.7?

What kind of compression are we looking at here?

Shortie headers or long tubes?


And I still say those heads are too big for your combo. 200cc runners are just too big for your combo. I would sell them and go with a set of World products Windsor Jr or Roush 180 heads or a set of used alminum TFS or AFR heads.

[420nitro]

Need more info on the cam specs. (380) is that the lift of the cam lobe? If it is...that would yeild you just over .600 lift with a 1.6 Rollor Rockers.
Look you can run that size head, but it would require alot of rpm and or a lot of spray. But what ever.
Whats the cam spec?
What intake?
zero deck?
Who's flat top piston?
How much of a piston relief in your flat top piston?
Carb or EFI?
How many cc's in the heads when done?

[tireburner163]

He listed at GT-40 intake, so I assume it's EFI.


And Nitro is right, to get power out of your combo with those heads your really gonna have to rev it. Higher than the 6250 fuel cut-off. You could get a RPM extender from Ford, but I don't think I'd wanna spin anything other than a built short block that high.

[420nitro]

Originally posted by tireburner163
He listed at GT-40 intake, so I assume it's EFI.

Oh yea....oops

Then that intake aint gonna work with the GT-40 upper on!! The only thing would be is to put a box upper on it. And the intake will have to flow about 15% more then the heads at peak cam lift.
Alot of work and $$$.

[srv1]

290-310 horse.

James

[tireburner163]

your combo with a good cam and the Roush 180 heads.

ballpark of about 325hp

[red82gt]

All I know is that is not a combo that should go together. Do some more research.

[MiracleMax]

Well lesse your engine displaces 308 cubes (3.07.7) and the roush heads feature 2.24 sq. in. of port area.

These heads in this application are good for about a peak torque value of 5100 rpm and since HP is a mathematical function of torque (I think peak HP is 1500 rpm higher than peak torque) then your looking at a peak HP value coming in around 6600 rpm.

here is the tech document on the Roush 200 heads from World Products.

http://www.worldcastings.com/tech/ro...inderheads.doc

this is a handy reference page for getting an idea about how to go about things.

http://www.newcovenant.com/speedcraf...ors/intake.htm

Conclusion

You at the very least need to make a manifold change to better take advantage of the heads and the ??cam??

The only easy info on manifolds I can find is from Edelbrock. Using the same calcultor suggests using the Performer 5.0 RPM (Which has an exiting port area designed for about 200 higher RPM)

so less'see a visit to the comp cams website and a check on the catalog suggests something in the 280 +/- adv degree range.

BTW, another rough estimation calculator for header length based on primary pipe O.D engine size and max revs fond here

http://www.bgsoflex.com/bestheader.html

suggests using a header with an 1-5/8 primary tube 31 inches in length.

Hooker makes a header with those dimensions as a regular stocking item.

Interestingly if you up the dia to 1-3/4 and bump the engine size to 347 then the pipe length remains about the same.

if anybody has flow figures for the Roush Heads (about 6 to 8 points preferably from .050 or .100 lift on up) I can plug these into a dyno sim for a rough idea on power. As well as compression ratio for 64cc heads and flat-top pistons.