BBC High Lift Camshaft Question

[rustbucket79]

It's been years since I've worked on those castings, but beware that those heads came with 2 different spring pocket depths. IIRC the installed heights were either 1.800 or 1.900 on the intake valve, and a corresponding difference on the exhaust valve. Best to check your heads long before starting work on them, you'll need the taller installed heights.

[nickpohlaandp]

...why are so many guys stuck on iron heads!... Aluminum really is OK for a engine...

You're not telling me anything I don't know. Trust me, I'd love to dump 50-60 lbs or more off my engine, run a bit more compression, so on and so on. Where are these cheap (under $2500) aluminum heads you speak of. Maybe where you live there's a few sets at every Goodwill, but not around here.

If you only knew how tempted I am just to buy a set of bare ProComps you'd understand the struggle within myself. I just haven't read, heard, or seen really anyone using them and that makes me wonder why. A good set of Dart or AFR heads just aren't in my budget. Maybe they could be an add on some day down the road, but for now I've got to work with what I have.

[nickpohlaandp]

It's been years since I've worked on those castings, but beware that those heads came with 2 different spring pocket depths. IIRC the installed heights were either 1.800 or 1.900 on the intake valve, and a corresponding difference on the exhaust valve. Best to check your heads long before starting work on them, you'll need the taller installed heights.

Good info. Thank you!

[CamKing]

If you're going to go with longer valves, go with ones that are long enough to fit a spring with 2.050" installed height. That will open up a lot more spring options for you.

Duly noted. Would you recommend staying with 1.7:1 rocker ratio or going staggered 1.7/1.8, or bringing both up to 1.8? Obviously the lobe lift wouldn't have to be as tall with a 1.8 rocker, I'm just curious about the effect it would have on overall performance. Also, going to 1.8 rockers seems like moving the fulcrum could possibly make it easier to break a rocker... or am I getting way ahead of myself? I've read about, seen in magazines and on TV, but never personally seen a broken rocker. I'm curious if an issue like that is a quality control escape, poor valvetrain geometry, excessive spring pressures, or a combination of two or more of those.

For what you want to do, stick with 1.7 rockers

[nickpohlaandp]

For what you want to do, stick with 1.7 rockers

I went back and opened up DV's book on budget BBC builds (his newest one, not the older one) last night. I was reading about rocker ratio, BBC's liking the exhaust with a little more duration, not necessarily lift, and just how important the intake lift, duration, and timing events are. I'm curious, why do you say stay with a 1.7/1.7 setup vs. a 1.8/1.7? Seems like there are gains to be had with the staggered setup.

Oh, FWIW I plan on getting whatever heads I use flow tested and having a cam spec'd with the COS-Cam program.

[blwilliams]

...why are so many guys stuck on iron heads!... Aluminum really is OK for a engine...

You're not telling me anything I don't know. Trust me, I'd love to dump 50-60 lbs or more off my engine, run a bit more compression, so on and so on. Where are these cheap (under $2500) aluminum heads you speak of. Maybe where you live there's a few sets at every Goodwill, but not around here.

https://phoenix.craigslist.org/evl/pts/ ... 63958.html

[nickpohlaandp]

...https://phoenix.craigslist.org/evl/pts/ ... 63958.html

Hmmm. Those look identical to these.

http://www.ebay.com/itm/BBC-CHEVY-496-5 ... SwAPlXgY0V

Then there's these (ProComp Oval port)

http://www.ebay.com/itm/BIG-BLOCK-BBC-C ... SwzgRWv21L

I'd like to stay with an oval port because I really think, from what I've read, that a rectangle port will hurt more than help me on my way to my end result. This engine is NOT going to be a trailer queen, drag race only engine. It'll live the majority of it's life on the street. I'm not opposed to the Rectangle port linked above (the Bravo heads), but I'd prefer to go with an oval port. Only problem is that I run into the same issue... I haven't heard of anyone using the ProComp heads with good results... and until about 5 minutes ago, I've never heard of a "Bravo" cylinder head. I imagine it's similar in manufacturing quality to the ProComp.

[blwilliams]

...https://phoenix.craigslist.org/evl/pts/ ... 63958.html

Hmmm. Those look identical to these.

http://www.ebay.com/itm/BBC-CHEVY-496-5 ... SwAPlXgY0V

Then there's these (ProComp Oval port)

http://www.ebay.com/itm/BIG-BLOCK-BBC-C ... SwzgRWv21L

I'd like to stay with an oval port because I really think, from what I've read, that a rectangle port will hurt more than help me on my way to my end result. This engine is NOT going to be a trailer queen, drag race only engine. It'll live the majority of it's life on the street. I'm not opposed to the Rectangle port linked above (the Bravo heads), but I'd prefer to go with an oval port. Only problem is that I run into the same issue... I haven't heard of anyone using the ProComp heads with good results... and until about 5 minutes ago, I've never heard of a "Bravo" cylinder head. I imagine it's similar in manufacturing quality to the ProComp.

The heads I sell on CL in the link above may very well be the same casting as you show from Ebay.
I guarantee they are not Procomp castings.
The Ebay heads will have imported valves springs retainers etc.
All of my heads have USA made parts. All parts are from Erson/PBM.
The heads I sell I have personally ran 7.85 175 in my super pro 498 BBC dragster.

[nickpohlaandp]

...https://phoenix.craigslist.org/evl/pts/ ... 63958.html

Hmmm. Those look identical to these.

http://www.ebay.com/itm/BBC-CHEVY-496-5 ... SwAPlXgY0V

Then there's these (ProComp Oval port)

http://www.ebay.com/itm/BIG-BLOCK-BBC-C ... SwzgRWv21L

I'd like to stay with an oval port because I really think, from what I've read, that a rectangle port will hurt more than help me on my way to my end result. This engine is NOT going to be a trailer queen, drag race only engine. It'll live the majority of it's life on the street. I'm not opposed to the Rectangle port linked above (the Bravo heads), but I'd prefer to go with an oval port. Only problem is that I run into the same issue... I haven't heard of anyone using the ProComp heads with good results... and until about 5 minutes ago, I've never heard of a "Bravo" cylinder head. I imagine it's similar in manufacturing quality to the ProComp.

The heads I sell on CL in the link above may very well be the same casting as you show from Ebay.
I guarantee they are not Procomp castings.
The Ebay heads will have imported valves springs retainers etc.
All of my heads have USA made parts. All parts are from Erson/PBM.
The heads I sell I have personally ran 7.85 175 in my super pro 498 BBC dragster.

(Dumb and Dumber quote) "You'll have to excuse my friend...."

I did not put two and two together that you were the seller. So is this a setup that you always have for sale, or is quantity limited? I'm not in a position to drop $1250 today.

Also, you say you ran 7.85... that's awesome. Are the heads you run worked on beyond what you sell, as in port work, valve job, etc? And how heavy is your car, if you don't mind divulging that info.