PROCOMP sbc cylinder heads

mrvette said:
Years ago in the Chem lab wing of a company I worked at, there was a Perkin Elmer Xray mass spec machine...they froze the sample in liquid nitrogen? and then pulled it out for shooting Xrays? and then looking at the readout, the machine was not very large, really, but the readout was across the monitor screen giving all that periodic table/density? element readout....

I would THINK something like that should be fairly common today, as I"m sure it was then....

thing is, just because ONE piece of metal from ONE head is say brand X, don't mean shit that the next one is....

:shocking::beer:
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I worked in the aluminum industry for 30 years.
When a furnace of molten is ready to pour a sample is taken and sent to the lab for analysis.
They burn the aluminum alloy with an electric arc and read the gases with a Quantometer. A printout tells if it is in spec or out.
If needed, adjustments are made to the metal in the furnace and then subjected reanalysis.

Pure aluminum is almost useless for any type of fabrication, it is to soft. About the purest aluminum a consumer will come across is 1100, aluminum foil.

I always chuckle at the term "aircraft aluminum.

I have no idea what this magical metal is.
We made metal for all sorts of aircraft, including Cessna's, 747's C5's, F-18's, Airbuses, MD80's etc.
Not once did I ever see any of this metal spec'd as aircraft grade, type or any other term.
It was 6061t651 or whatever alloy and temper the aircraft builder ordered.
It was the same metal as any other metal of the same alloy and temper ordered by someone else to build say garbage compactors or whoozits.
Heck it may have even came out of the same pour in the furnace as that wing spar for the aircraft order.

There are about 1000 alloys of aluminum, many of which are a proprietary alloy.
The first digits are the alloy, the Txxx is the temper.
Remember the Quantometer?
All the aluminum companies have them.
Wonder what the competitors alloy is, simple - burn it..
The trick is how did they make that combination of alloys work.
That is the secret part and often very hard to replicate.
 
My one comment about this thread. EVERYONE seems to be making FLOW NUMBERS the standard bearer of what constitutes a "better hea" or not.....just sayin.

I have been saying this for YEARS!

Flow numbers are nothing more than a marketing scheme and do not give a clear indication of which head works better than any other head, there are MANY more factors to consider...
 
jsssgrl1209 said:
I bought a pair of Brodix Track 1 heads for my 434 small block stroker. They were cnc machined and the intake runners were not smooth......they had little tiny machined "steps" or ridges around the entire intake runners. .


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This helps atomize fuel in your engine. It is hard to see in the pic and in person the ridges are much more noticeable and easy to feel.

The reason fuel injected engines dont need help with atomization is because the fuel is being sprayed into each port directly. So it is already atomizing.

While on a car with a carb fuel is sprayed into the intake and then flows into the runners, without much atomization....it works but isnt the best process.

For anyone who is not sure what atomization is......here is a simple explanation. It is the process where fuel is broken up into a bunch of smaller drops allowing it to burn more efficiently. Its like turning your garden hose from full stream to mist

~~~the pic is not of the heads I bought, but a photo of Brodix heads I found on the intenet.~~~~ My heads cost around 1750 and were not cheap........brodia track ones 1150 cnc track ones 1750 steep!
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Oh geeze....Those are really nice heads. Good choice.

HOWEVER, atomization has more to do with chamber deisgn than runner design. Those ridges are there because that's the way the tooling works.
 
76BluRay said:
any more updates?
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I removed all valves for the second time, to see if I overlooked something. Again, I found out that no extra work to the runners and bowls was needed. All runners are perfect as cast, much better than expected! The Edelbrock - Vortec inlet manifold (see my previous posting), however, had uneven casting, but is now port matched. All other major parts are ready to be installed. I'll come back to you about the engine project, hopefully comming summer. Just now, replacement of T/As and installing Steeroids have to come first.

Arne
 
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About 1 year has gone since I posted on this thread. The Steeroids is now installed and so are a set of T/As. A new 3.55 diff (swapping the original 3.7) is still waiting for its turn. :bounce: My 78 L82 has now improved handling drastically and is at last ready for more power. I have made some alterations in plans because after my final inspections of my PC3003 PROCOMPs, I clearly see that these nice cylinder heads really "deserve" some "better" parts. As you see from my posting, I was planning to use a XE268H cam and a Edelbrock 1411 750 carb. The new consept is XR282HR roller and Holley Street Advenger 770 (0-80770). All parts are bought and waiting to be installed. As for the inspection of my PROCOMPs, I could only find some minor dips under the valve seats. They were so small (approx. 0.1 - 0.15 mm) and not subjected to any modifications. So the heads will be installed without any porting. On the Edelbrock 27164 inlet manifold, however, port matching was needed. The Eddie had some bad casting, which is now grinded out. Well hopefully I will speed up the work now, because my old 350 is sold and the new owner is waiting! Hopefully I'll get some time to post some pics as I go along with the mods and engine swap.

Arne
 
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I heard that Comp bought them a few years back, they may have gotten better. When I read about a flow test done on them way back when, they flowed similar to Vortec heads. Which isn't all that but it's not horrible.

If I were you I'd keep the 210s, street driven or not. With those heads I think you're better off.
 
My PROCOMPs are Vortec style like with much bigger runners. If they don't flow better than the 906s I will be amazed, even with modified extended lift above 0.500". The bowls have a distiguished port bias, all fully according to the book. They look very much the same as the new Edelbrock E200. To be on the safe sideI bought a complete retrofit cam kit, K12-432-8. Last night I changed springs, retainers and stem locks. The old ones are no-brand (made i USA I was told) for flat tappet cams up to .600 lift. The valves and seals seem to be OK, so kept them. As for now both heads are ready for installation.

Arne
 
The XR282HR cam is now installed.

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first a installed this button ....

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but shimming was not easy, so I ended up with this easy-fit:

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Arne
 
... and the aluminium timing cover is installed, but timing tab does not fit ....

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.... and the short aluminium water pump seated with some light grinding to match....

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Arne
 
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Head gasket (expensive!) choosen and installed.

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Heads are installed and torqued.

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Which rockers to use?

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Tried these first.

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... but they wouldn't fit under my valve covers....

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Arne
 
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roller rockers won't fit under tall valve covers??

Is it interfering with that screw in baffle under the hole?

Does it say PEP on those rockers as in CAT PEP/California Auto Transpeed? If so, I'd use the other ones.
 
I didn't investigate closely, but it seems like I would need wider covers. The pusher side of the rockers touched the inside wall. The height is ok. I had two sets of rockers available so I went for the tip roller CC Magnum. They'll do for now and I'll see what I do when I retorque the heads.

Arne
 
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Hello Guys, I read a thread somewhere that indicated covering the pin with the locking plate would prevent it from falling out (if it ever got loose) and causing damage to the timing chain and gears. Why is there a hole for the pin in the locking plate anyway. My new Comp Cam timing gear set came with a plate with only the three bolt holes in it. I am building up a 383 with Procomp heads, thumper retro roller cam, timing gears, and magnum roller rockers.
 
Eagle, don't know where you read that but I would be skeptical. For one thing, the dowel should protrude from the alignment hole in the sprocket so bolting the retainer over the pin would prevent it from seating flush. Now if you were truly worried about such a thing, I suppose you could file the dowel flush with the sprocket and then bolt the lock plate on however you feel like. Hell, that's really not a bad idea. But the reality is in all the engines GM has made around the world you could probably count on one hand the number of times that dowel pin has fallen out of a cam.
 
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