PROCOMP sbc cylinder heads

I bought my set of PROCOMP cylinder heads from http://stores.shop.ebay.com/GR8HOTRODS__W0QQ_armrsZ1 GR8HOTRODS.COM is amongst many that offer this brand at very low prices. First I ordered a set of 190cc heads with 68cc combustion chambers. According to adverts they are sold as PC3002PT. Shortly after I was told that the seller that the 190/68cc was out of stock and we agreed that I’ll wait for a set of 68cc chamber heads when available. Because of CR issues I decided to go for 68cc chambers rather than 64cc, which was available at that time. Couples of weeks later I was informed that the seller had shipped a set of 68cc. When I finally received the heads, I noticed that the cylinder heads were stamped with PC3003. As per the URL www.procompelectronics.com, the PC3003 would be 210cc runners with 64cc chambers. I’ll come back to my detailed findings as I progress in this thread.

This pic is taken from Procomp Electronics:



Yes I know, these heads are moulded in China, sized, milled and assembled in the United States …., but I also know that so are my Scat stroker crank, my flat top pistons and so on. I ensure you that I have no agenda when I publish my findings and you must all take it for what it is and make up your private minds. However I feel somewhat obliged to tell you the facts, when I have my hands on these very cylinder heads, which a lot of people have spoken so negatively about. Some issues may be true, but I don’t think that those horror stories apply to the pair of cylinder heads I have inspected, that is for sure.

The supplier has done his “best” to hide the orginator. :lol:




Arne

did you buy them assembled or bare?

i got a bare set of 190cc procomps from guru for $250 never installed. I need to get some 202 valves.

Mine are with OEM valves (2.02 and 1.6) installed. All components are purchased from Precision Engine Parts, Las Vegas. The valves are 21-4N stainless. The springs, retainers, locks and rocker studs are the best steel available (according to the supplier Gr8HotRods). Valve seals are Viton.


http://www.precisionengineparts.com/



Arne

When I received the cylinder heads this Easter, I made a thorough visual inspection. I was in general very pleased with the quality of cast and machining. Both intake and exhaust runners are good for direct bolt on. So are combustion chambers. The cast inside is quite even and will not require much work to be perfect. The PC#3003s are told to be of a newer cast, different to older casts. I have not tried to prove the justification in this statement, but it seems to me that the cylinder heads I have received do not look like those being frequently posted by the hardcore disbelievers. All combustion chambers had a good even surface and without blemishes of any kind. The valves were evenly seated and correctly spaced. I noticed that there was a 0.7mm height difference between I/E measured on top of the stems. I don’t think that will make any difference to the valve train geometry.












Arne

I inspected all threaded bolt holes and found no imperfections except for rocker bolt holes. They were all drilled half thru the intake runner upper wall, see pic. This must be observed and fixed prior to installation. Burr edge must be removed and rocker bolts threads properly sealed. Easy fix, no worries, you find this almost all OEM cylinder heads with threaded rocker bolts.


Arne

I did the gasket alignment, using the FelPro #1003 head gaskets The #1003s and the ProComps have a perfect match. Both cylinder heads are tested.



Arne

Looks as good as that set of Edelbrocks I had some years ago....

:surrender:

The cylinder heads I received have slanted intake runners like the GM Vortec heads. The inlet runner height is much higher than standard and calls for other than standard gaskets. The following pics have FelPro#1206 installed to show the actual match or mismatch if you like.


I tried to see how the Edelbrock Performer EPS will fit. The reason for using Edel EPS:
http://www.vettemod.com/forum/showthread.php?t=3449



... here with the FelPro#1206 installed. Inadvertently the gasket is placed inside out, but never mind...:


The mating flange of the Edel EPS is too small and does not allow much metal removed if you want a good match between runner and intake. How much that means to power loss is debatable, but I’ll look for a better solution


Arne

Luckily the PROCOMs have Vortec bolt pattern and the Edelbrock Vortec EPS has much larger flange which allows sufficient metal removed. The Vortec flange requires different gasket (FelPro#1255) and fasteners (4 off each side). Just to illustrated the different runner patterns the #1206 is shown here.





Arne

It seems that they are cast very well

How much do they weight?

I've heard the ProComps don't flow very well, you're probably better off with the 210s anyways. Just buy a thicker MLS HG to lower the compression, you can lower it more than 1/2 a point with just the HG.

Thank you for interesting comments. I’ll come back to weight and flow later when I have finished liquid tests of cavities. As for head gaskets and lowering compression ratio, I have discussed this in detail in my thread:
http://www.vettemod.com/forum/showthread.php?t=3918

Arne

To day I liquid tested the PROCOMs combustion chambers to be 67.5 cc. All eight were of equal size. After a thorough inspection of the intake runners I got a good impression of the total quality of the cylinder heads. The intake runners show an excellent shape, size and smoothness and evidently there is no need for any modifications for my purpose. The bowls just behind the valve have been frequently reported to be of poor quality. My PROCOMPs have no evidence of such and show a smooth surface. The bowls could of cause have been improved to obtain higher flow, but my build is a mildly tuned street engine and does not call for such modifications. Drivability is the most important goal and the speed of flow at low lifts is far more important. The Edelbrock 27164 SBC Performer EPS Vortec manifold had some imperfections inside just at the mounting flange (see pic). I decided to go for a simple gasket matching job to adjust the larger intake runners of the PROCOMPs. I used FelPro #1255 ( 0.120”) and the obtained match is satisfactory.







-------------
Arne

arneoe said:

To day I liquid tested the PROCOMs combustion chambers to be 67.5 cc. All eight were of equal size. After a thorough inspection of the intake runners I got a good impression of the total quality of the cylinder heads. The intake runners show an excellent shape, size and smoothness and evidently there is no need for any modifications for my purpose. The bowls just behind the valve have been frequently reported to be of poor quality. My PROCOMPs have no evidence of such and show a smooth surface. The bowls could of cause have been improved to obtain higher flow, but my build is a mildly tuned street engine and does not call for such modifications. Drivability is the most important goal and the speed of flow at low lifts is far more important. The Edelbrock 27164 SBC Performer EPS Vortec manifold had some imperfections inside just at the mounting flange (see pic). I decided to go for a simple gasket matching job to adjust the larger intake runners of the PROCOMPs. I used FelPro #1255 ( 0.120”) and the obtained match is satisfactory.









-------------
Arne

Click to expand...

About what I did on my China Heads. I did a little bowl work, just couldn't stop myself.

turtlevette said:

did you buy them assembled or bare?

i got a bare set of 190cc procomps from guru for $250 never installed. I need to get some 202 valves.

Click to expand...

man that is a deal

arneoe said:

To day I liquid tested the PROCOMs combustion chambers to be 67.5 cc. All eight were of equal size. After a thorough inspection of the intake runners I got a good impression of the total quality of the cylinder heads. The intake runners show an excellent shape, size and smoothness and evidently there is no need for any modifications for my purpose. The bowls just behind the valve have been frequently reported to be of poor quality. My PROCOMPs have no evidence of such and show a smooth surface. The bowls could of cause have been improved to obtain higher flow, but my build is a mildly tuned street engine and does not call for such modifications. Drivability is the most important goal and the speed of flow at low lifts is far more important. The Edelbrock 27164 SBC Performer EPS Vortec manifold had some imperfections inside just at the mounting flange (see pic). I decided to go for a simple gasket matching job to adjust the larger intake runners of the PROCOMPs. I used FelPro #1255 ( 0.120”) and the obtained match is satisfactory.
-------------
Arne

Click to expand...

Thanks for posting this, you have my attention and interest. My local speed shop sells Patriot heads complete with 2.02 intake ss valves and 1.6 exhaust valves, 190 cc runners and 64 cc chambers and springs good up to .580 lift. The heads have been CNC machined to Fel Pro gaskets and look absolutely perfect for $880 complete. No porting necessary. Things happened and I had to postpone my purchase, but now you have me thinking. My purpose is for a street/strip machine, so reliability is a high priority. For $700 I think you got a deal. Post results after you have it running. Ooh..and BTW, what is wrong with the 64 cc chamber?

It is nothing wrong with a 64cc chamber, but just for this build I wanted not to exceed CR 10:1, due to the pump gas available locally. A 64cc chamber for my 383 would result in approx. 10.5:1 and a 68cc 10:1. I may reconsider this and go for the .041” FelPro because of the measured 67.5cc chambers.

I have also considered the Patriot 190cc, and if I should believe what have seen from flow specs, they are even better than the PROCOMPs. I have never had hands-on the Patriots and have to rely on what people say. From my sources, I have only heard positive remarks about the Patriots. I have “filtered out” CF and some other related forums, which in my little world does not count as reliable sources in this case. It would be nice if members here on VetteMod shared with us their experience with the Patriots. Surely someone here must have first hand information on this topic.

The reason for buying my PROMCOMPs, was solely out of curiosity, I just had to find out if they were bad or good. From what I read on CF, the odds were not very good…. Anyway from what I have seen so far, all seems OK and there is nothing wrong with my PROCOMPs … that is for sure. Probably they are no CNCed AFRs, but well suited for someone that wants a build for less money and reasonable results.

I’ll take you further as things progress, but it may take some time, fall and winter are soon here.

Arne

Thanks arneoe, another point of interest is that you cc'ed the chambers to find they are all equal in volume. My thought this lends testamony to the quality of the casting; unless they were machined, and that doesn't appear to have been done. Also, I notice yout heads are going on a 383 and what I decided to do with my 3970010, four bolt two piece main seal block. It will be decked to get as much compression possible with pump gas. My plan is to spend the extra bucks and make it a roller motor.

Maybe, you can share some of the particulars of your build like what rotating assembly and cam you chose? My experience building engines has been limited to stock motors with an overbore, so I'm on that learning curve. Next Monday, while I'm in the area, I am going to stop at Murray's Speed and Custom to see if he still has those Patriot heads I mentioned. If he lets me, I will take a few pictures to post here for comparison; if you don't mind?

I agree with what you say about some attitudes about those China heads. I'm sure at one time there were casting problems, but it seems they have been solved and a thing of the past. Thanks again for posting your finding!

Red said:

Thanks arneoe, another point of interest is that you cc'ed the chambers to find they are all equal in volume. My thought this lends testamony to the quality of the casting; unless they were machined, and that doesn't appear to have been done. Also, I notice yout heads are going on a 383 and what I decided to do with my 3970010, four bolt two piece main seal block. It will be decked to get as much compression possible with pump gas. My plan is to spend the extra bucks and make it a roller motor.

Maybe, you can share some of the particulars of your build like what rotating assembly and cam you chose? My experience building engines has been limited to stock motors with an overbore, so I'm on that learning curve. Next Monday, while I'm in the area, I am going to stop at Murray's Speed and Custom to see if he still has those Patriot heads I mentioned. If he lets me, I will take a few pictures to post here for comparison; if you don't mind?

I agree with what you say about some attitudes about those China heads. I'm sure at one time there were casting problems, but it seems they have been solved and a thing of the past. Thanks again for posting your finding!

Click to expand...

I dunno if you can retro fit a FACTORY set of roller lifters or not, but those toggle things in pairs....I have seen pix of them breaking and wiping out a ton of expensive shit.....fine for a petted over race car, but there is a reason GM went dawg bone along with Mopar, that I know of, for holding them lifters from twisting.....

maybe get a later 80's truck block, that's what mine is....'89 one piece roller block from the factory...4 bolt mains to boot....

:gurney:

Red said:

I agree with what you say about some attitudes about those China heads. I'm sure at one time there were casting problems, but it seems they have been solved and a thing of the past. Thanks again for posting your finding!

Click to expand...

The next thing China needs to make is a SBC block. $4000 is just too much. You're paying for all those losers to go on disability.