Lee Weltens

I hope im in the right forum . If not please send me in the right direction . Im hoping to build a 350 to 400 hp engine for my truck . I have a freshly rebuilt 2 bolt ( block # 3970010 ) I picked up msd ignition with blaster 2 coil , 461 heads ported and polished with ss valves . I really need help on putting the right parts along with the engine to give me a 350/400 hp engine . Itll be bolted to a turbo 400 with a stage 3 shift kit going back to a ford 9 inch rear end with 456 gears . Clearly I am not an expert at this so any help or advice would be greatly appreciated . The i take is an edelbrock performer pn 7116 and i have a choise of a holly 650 double pumper or edelbrock carb pn 1406 . Thanks everyone ..Lee .

Exgie

Ok well you need a small chamber high flow head. You need about 250CFM I 190CFM E 9.5:1 compression. a cam that looks something like this 10/0.520 lift split, a 230/236 duration split and a 110-degree lobe separation angle. Then run a single plane intake. That should get you around the 400hp target.

It is all going to to come down to the cylinder heads which I don't thin 461s are going to cut it without going stupid radical on other things. 461s will get you about 350 streetable hp.

Lee Weltens

Hey thanks for the reply Exgie. Thats the kind of info I need . The cam you mentioned. ...what manufacturer do you recommend. The guy I bought the heads recommended a 280h . Also which intake would be best . You mentioned a single plane . Again who do you recommend. Thanks for all your help .

Richard Till

Compression ratio? How many rpm`s are you expecting to turn when crossing the line? The cam manufacturer is not as important as the advise on the chosen numbers.

Lee Weltens

Hey Richard .Thank you for the input . Seeing as they are 456 gears in the back , im expecting to be at a fairly high rpm . Whay exactly ...I have no idea . Any thoughts? Thanks for your help . Lee

Exgie

Well we already established 9.5:1 is his target. What it really is we don't know. That was based off a 63cc chamber with a stock piston, which is also a guess. If you are 1/4 mile racing it might be important what RPM you are crossing the line at. If not then it is not important. What is important is the RPM range you want to run in and where you want the power. Yeah, I suspect a 456 gear is going to RPM high, however, tire size and transmission gearing will play into it as well.


I do not believe the heads are going to pull 400 HP.

Yeah cam manufacture doesn't matter that much. Whoever has the cam that will be a good match for what you are trying to do.

It is like baking a cake. You need all the right ingredients in the right proportions for it to be a cake and a good cake at that. I am basing my info off a proven recipe. How close it is to your motor is largely a guess.

A Performer intake is a dual plane. Again it doesn't mater a lot whose intake, but a good single plane low rise intake. Maybe a mid rise if the RPMs are going to be up there consistently.


A comp cams 280h is

• "Magnum" Hydraulic flat tappet camshaft and lifters.
• Fits 1955-1998, 265-400 cu.in. Chevrolet V8.
• RPM range: 2,000 to 6,000 rpm
• Duration at .050" lift: 230/230 (int/exh)
• Valve lift with 1.5 rockers: .480"/.480" (int/exh)
• Needs headers and lower gears, rough idle.

which is in the neighborhood of what I mentioned.

Lee Weltens

Thanks again Exgie . I believe the pistons are stock , as I have the engine on a stand , tin and heads off , now would be the time to upgrade the pistons . What would you suggest I put in my " cake ". And thanks again for all your help!

Lee Weltens

Also .... The cam you mentioned earlier , when I go to the shop . Do I give him the numbers you gave me and get him to match that up ?

Exgie

You need to cc the heads and get a piston that will give you 9.25 - 9.50: 1 compression.

Exgie

Yes just tell him what you want. Personally I prefer a split grid cam I.e. where the exhaust and intake are ground different.