Hey guys, I just input my big block project data in desktop dyno and got 609hp @6500 and 576 lbs/ft at 5000 rpm, whats your guys' opinions on these numbers?, heres my combo. The motor Im building is a 468 big block w/ 11:1 comp. I will be using GM Signature Series aluminum rectangular port heads w/ 315/300 cc int. port and 110cc exh. port but for desktop dyno I entered oval port pocket ported heads to bring the #s down and make them more accurate and valves are 2.19/1.88, my cam is a 294* total duration int/exh and 248 @.05 int/exh w/ 110LSA and .595 total lift. Holley 850 cfm carb and victor jr. single plane intake, open headers since it will be a race motor ill probly choose hookers cuz im not rich ... anymore after this build. So what do you guys think does 609 hp and 575 lbs/ft sound reasonable for this motor?? I hope it is because my goal was to build around a 600 hp race car that i could drive on the street.

If you have a motor like mine please tell me your hp and tq #s and 1/4 miles, im hopin for 10s if i dont get it NA ill be spraying
Thanks

 

Did you get a curve, or just peak #'s?

1.3 HP/CI is a pretty healthy NA engine. I'm not doubting it's possible, but am curious about the specifics of that cam. It has slightly more duration than mine, but not more lift. Everything sounds fine to me, although I suspect that is a hydraulic cam, and solid lifters really do nicely with higher lift BBC cams. I'm lovin' mine to death.

The only incongruity is the part about streetable. Open headers and retangular port heads don't go along with streetable.

I hope you have a 6-point rollbar in your budget. Along with other drivetrain upgrades. Whatever you spend on the engine, figure on spending at least that much more backing it up.

 

Actually the cam im using is a solid flat tappet by comp cams if you wanna look it up on summit the pn is 11-219-4. Also to clarify the car is going to be a race car and not designed for the street at all but for fun Im gonna drive it on city streets from time to time. As far as backing it up im going w/ a 10 point cage, already have a strange 12 bolt, and am looking at gettin a ProBuilt Turbo 400 to back up my motor.

 

Sounds simmilar to a couple of combos I have had over the years my current one is an old 408 ci BBC with a 510/515 lift hyd roller with a Team G /800 Holley and .250 domed forged pistons, oval port "semi open" chamber (390 HP,427 vette heads) port & polished, Manley rods, steel GM truck crank, the engine was dynoed at 503 HP@ 5700 RPM on the engine and 830 HP @ 6200with a 350 HP plate this engine has been my daily driver in my 78 Z28 until I recently purchaced a 88 Pro Street T/A that is getting the same engine with a new fogger or possibly another plate, I took the plate off the 78 and never ran the N2o after the dyno runs, no hood clearence! but the bird has some extra so Im going to put something back on ... this engine would put the 78 into the high 12s on the engine so an extra 100 HP should put you close to that 11-10 sec range , just expect some drivetrain loss, and gear the car for the RPM range of the engine.. it'll take some tuning but it sounds like a good start!

 

Ah, a Magnum grind. When I started looking at cams a couple of years ago, i asked them about a Magnum cam. They responded that while it would make more peak HP & torque, an XE cam of the same duration would make the car faster because it would make more power earlier.