ive heard anywhere from 30-80hp gain going with the MCs over the orig.im trying to decide what is the best bet.

That sounds about right, it depends on how much you're willing to spend on port work, and who does it. Hemphill might be able to get more but $$$.

having a hard time deciding on what to do.....i like to do things once im shooting for 950-1000hp. i know pred deal would be the best bet but i already have 2sets of wedge headers and would have to build for the preds and $$ for the pred stuff too.hows koffels cnc program?i spoke with Hemphill too he is same $$ as koffels or i might let my guy locally do em hes got some pretty impressive #s from the origs.

How many cubes are you thinking... the bore does
get a bit tight with the 2.4 valve on the MC

540-557 havent made a decision but 4.5bore

If you have to buy castings, makes no sense to go originals. Get mc's and be done. Porting should cost the same.

you can hit that hp range with the originals. my 528ci made 994hp on the dyno (i know this dyno to not be a happy dyno). this was with originals ported by koffels.

yes i know the origs can make 1000 and the porting cost the same my situation is i can buy a set of origs locally or buy new MCs at $3000+ diff in price.so 3k worth the gain in hp?

M/C's are easily 1000HP with a 4.500 bore and can get to the 1100 range too. As said, get the M/C's and have room to grow with a cam change. If the price of Koffel's and Hemphill are the same, I would have Hemphill do the porting. He's been doing it almost as long as Koffel and I've heard some impressive numbers out of his stuff. Nothing against Koffel, just what I know about Hemphill. I wouldn't have someone experiment on them, that's for sure. JMO

Buck did the originals on the 572 that Wade built. That was a fairly low compression pump gas motor with not near a max effort cam that made over 900 on pump swill with ease. So the question is how much power you want. If what you quoted above is all you want, the extra 3k tag for the MCs makes no sense

Have a friend with a 570" Pontiac with Edelbrock heads that makes over 1100 with a head that flows maybe 400 on a good day. So it's not JUST the parts........it's the effort

my goal is low maintence piece easy on parts.....compression i dont mind i run Q16 now... id like to make as much power as possible and be able to drive on the street alittle and not have to change valvesprings etc every season.what kinda max power is achievable with that in mind?

Best bet for something like that is a boosted motor. If you have E85 local it's even better.

I hesitate to post anything on this site anymore. I'm not trying to rotate the earth with my combo so it is what it is. Here is the flow sheet for my B1-MC's recently sent to Modern Cylinder Head for their CNC program and valve job.

Nice! Mid lift #s are excellent. I would think 1100 is possible with an all out effort.

thought about getting modern to do mine and the price is way better than koffels but they never answer the phone.

Bob can be hard to get on the phone, keep trying to call or you might try sending an email moderncyl@aol.com

I agree like we discussed before. I would go with an MC head if B1 was the direction I want. But I have both and a set of Predators. IMO its all in who does the port work, how much you want to spend and how fast you want to go. I have a set of CFE Originals that are nice and made a tick over 1000 in a build that was meant to be in a bracket car.

I would go MC's if it were me. Better to have to much than not enough. Al is correct make sure the port work is done by somebody that knows what they are doing.

yup Al knows his stuff.....i think for how old buddys heads are new is the way go.