air dyno

forvicjr · Post by **forvicjr** » Fri Jan 01, 2010 8:14 pm

? .030 454,stock781, heads stock replacement pistons,RPM air gap intake,750holley,cam11-420-8 comp hyd roller,double roller chain,1.7 magnum roller rockers(comp) Estimated power????

Thanks vic...

#84Dave · Post by **#84Dave** » Sun Jan 03, 2010 2:38 pm

1086 HP ??????????????????????????????????????

David Redszus · Post by **David Redszus** » Sun Jan 03, 2010 11:58 pm

#84Dave wrote:1086 HP ??????????????????????????????????????

I bid 1125 HP

Post by **Stan Weiss** » Mon Jan 04, 2010 12:15 am

If I have the spec.'s on that cam correct it is only 215 / 215 @ 0.05
450-500 HP

Stan

Keith Morganstein · Post by **Keith Morganstein** » Mon Jan 04, 2010 7:59 pm

Stock dish pistons and stock 781 heads.... maybe 350 hp with that cam.

OTOH, small dome pistons, larger valves and good bowl / short turn work, good mid 230's cam and a bigger carb and you could add 100HP.

crazyman · Post by **crazyman** » Tue Jan 05, 2010 3:01 am

I would hazard a guess between 345-395hp.

Depending on your goals, I would have to agree that the stock pistons are killing your potential.

I know it's not the right thinking (terminology, hear me out) but it's better to have too much suction on a head that can't flow than it is to have a head that flows too much without enough suction. (I know, high pressure seeks low presure)

According to what I've learned, a 204 214 is about the biggest cam you can run with a stock convertor on a typical SBC. So 215 is probably about the same in BBC speak.

That cam is pretty tame, but you'll still better the stock numbers by 30 each, conservatively.

Your intake choice probably made the biggest gains on your setup.

IMO, an RPM intake is too big for that cam and compression unless you rev the snot out of it all the time. Then why not have the cam and compression in the first place? If all else stays the same, I'd choose a performer, or a stealth with your specs.

Choose your goals, then tell us about them, so we can help you more definitely.

Mismatched components are a high school thing. Some guys never get out of the cycle.

(sorry, probably 9 edits. I keep editing until someone else replies)

I like your term, air dyno, Tenth edit.

MadBill · Post by **MadBill** » Tue Jan 05, 2010 3:25 pm

Aren't you glad the 're-post' timer is down to what, 15 sec. now?

Carroll · Post by **Carroll** » Tue Jan 05, 2010 4:27 pm

A friend of mine did a simular engine made 400hp. and around 450 tq.

Joe C

forvicjr · Post by **forvicjr** » Wed Jan 06, 2010 6:08 pm

Havent been here in a while. The engine is temporary,its in an 81 vette,got ruffly $2000 in it. bought as an assembled engine with the idea it was a probable bad biuld. The engine only ran few min so the parts it came with was not hurt.(it was a horrible build by the way)So i had it touched by a hone by my machinest to clear the cylinders to seat new rings,And here i am. The 81 was a small block car and i wanted a BB, but with the economy the 496 in my plans was out money wise until i found and saved this motor.I just wanted to have an idea where it stood HP wise. I would have ran a bigger cam but thats what it came with,along with the rest of the motor.All i had to do is redo it and add carb and dist. Any ideas are welcome as i was hoping for around 450HP if its out of reach without major parts changing Ill deal with the 350 to 400 HP mark.

Thanks to all that responded

Not dish pistons, there flat with two valve reliefs,think its a 70 model truck engine.

forvicjr · Post by **forvicjr** » Thu Jan 07, 2010 4:03 pm