PROCOMP HEADS ------ STICKY------

billandlori wrote:From what I gather, if you have to go and do a bunch of porting to get them to work you would be money ahead using iron heads and follow the mad porter's instructions. Its not a cheap hobby but the iron heads would be more economical.

Bill

IF you are going to port iron heads to the Mad Porter's recomendations, isn't that "doing the work yourself"...?
I don't know how many heads you have ported but, I'd certainly rather port on aluminum instead of cast iron , any day.

rmcomprandy wrote:

billandlori wrote:From what I gather, if you have to go and do a bunch of porting to get them to work you would be money ahead using iron heads and follow the mad porter's instructions. Its not a cheap hobby but the iron heads would be more economical.

Bill

IF you are going to port iron heads to the Mad Porter's recomendations, isn't that "doing the work yourself"...?
I don't know how many heads you have ported but, I'd certainly rather port on aluminum instead of cast iron , any day.

That is true!! Iron does take longer to port.

If you had to buy ProComps then pay for cnc or buy iron heads from Scotty with the porting done it would be more economical for the irons. If total cost/HP is the issue this would be the way to go. GOOD CNC porting ain't cheap.

Bill

I bought some because of the ebay ad that bruno posted as well as the flow numbers listed. the flow numbers where not as advertised (i don't have the out of the box flow sheet anymore, but the peak intake flow was around 260 cfm) the 'valve job' was such that the valves would not fully seat the valves and guides where so tight to each other that it was verry difficult to remove the valves from the heads. the intake valve spring pockets on one head where deeper on one head than the other. long story short. the heads are not ready to run out of the box. it cost me almost 1200 dollars to have them brought up to usable condition (i had the guides honed, the valve job re done and a mild port polish job) for what i spent between the "ready to run cnc procomps" and the work they required, i could have bought p51's and sevral cases of beer.

I have sold a lot of sets to be run on street engines however, I get those castings bare and hone the guides, install good valves with a good valve job and minor bowl port work.
I sell them for $1,195.00 a pair with the valves and NO spring seats, seals, springs, retainers, locks or studs & guideplates.
They flow about what a warmed-over, (not completely ported), bigger valve pair of D3's will do. I have dyno tested them "back to back" and seen no appreciable differences in power one way or the other; although the aluminum heads will accept a bit less octane fuel.
That the aluminum tends to not detonate as much at higher water temperatures is the major difference.

They are certainly NOT a race head but, do a decent job IF you use them where they have their place.

In my mind...

Easier to port than iron. Save some weight over stock heads. Cheap if you don't expect much out of them. Market will be flooded with them, so in a few years may become a viable swap-meet alternative to stock iron castings.

Things to consider are... Are the valve-seats going to fall out after some run time? Are you putting Americans out of work by purchasing them instead of a US product? Are you going to be embarrised when your buddy out runs you with his iron-headed BBC ?

.

One of the problems I see is these heads just plain don't work compaired to the tfs streets, p-51's scj's ect and they Throw in a fancy "shiney" cnc job and alot of people think that because they are cnc ported "the turd has been polished"......... Wake up!!! A bad design is a bad design!!! Doesn't matter how cheap it is or who made it!!!

D0VE C filled with brass 230 max cfm 1.75" valve
Procomp raised very much like the TFS street. 251 max. 1.76 tuliped exhaust valve.
D3 with no floor fill but a bunch of port work. TFS cutter on seats. 1.8" exhaust valve. 214 cfm max.
Decent flowing P-51 research prototype. 1.76" tuliped valve 250 max cfm. Later P-51's max out at 262 cfm.
Out of the box SCJ casting.
Iron cj with typical mid 80's exhaust port work tweeked by RHP

Heads were flowed with 2" primary header pipe 4" straight off of the flange with one 90 degree bend vs the crites #8 primary for the 67 galaxie which abruptly turns down off of the flange and has a 50 degree bend.

Dove straight / crites..... P/C straight / crites....D3 straight / crites... P-51 straight / crites.. SCJ straight / crites... Iron cj straight / crites

.200" 116 / 114..............115 / 113..................107 / 106..........116 / 115...........102 / 101.....................104 / 103
.300" 156 / 150..............160 / 151..................145 / 145..........151 / 147...........139 / 136.....................142 / 140
.400" 184 / 176..............198 / 187..................176 / 174..........178 / 174...........164 / 160.....................169 / 165
.500" 205 / 192..............226 / 207..................201 / 196..........204 / 200...........184 / 182.....................189 / 184
.600" 217 / 204..............238 / 218..................213 / 209..........227 / 219...........197 / 192.....................200 / 194
.700" 224 / 209..............245 / 223..................214 / 211..........238 / 230...........207 / 199.....................207 / 200
.800" 230 / 213..............251 / 226..................214 / 210..........250 / 239...........211 / 204.....................210 / 204



So looking at this, why is the procomp getting such a bad rap......they outflowed everything else tested.....am i missing something......this is from mad prters post on exhaust stuff.....just a copy and past....

Flow numbers are only a small part of it........to many are hung up on flow this and flow that, shine this and shiney that......... Its about how much power they make and how fast they go.... Not the flow!!!!!!!! They work only marginaly better (if that) than factory stuff!!! Flow means nothing if power isn't produced !!!

It appears we will have another "knowledgeable" guy to gather info from on these heads...

http://www.youtube.com/watch?v=UDfZGPqxs5g

Ohh Jon...

Tee hee hee

agreed,a lot of people worry to much about peak BIG flow numbers.they don't worry about low-mid lift flow,velocity etc etc.. my brother wasted his money on the chinese junk,the only benefit was the car lost some weight,but by the time he fixed all the cheap junk ie valve seats,guides and the horrible ports he had almost as much in them as he would have a quality proven cylinder head.theres a lot of opinions on here about the pro-cough heads,but from personal experience save the time and money and do it right the first time

Les must be tryin to slow his car down some..............

They certainly HAVE their position in the marketplace for only certain applications ... used anywhere else and they are a terrible deal.

richter69 wrote:Les must be tryin to slow his car down some..............

what a F'n A Clown........ You know a good set of D3's would make that turd faster.

And being able to see over the steering wheel with out a booster seat and reaching the pedals would't hurt either.........

frank13 wrote:D0VE C filled with brass 230 max cfm 1.75" valve
Procomp raised very much like the TFS street. 251 max. 1.76 tuliped exhaust valve.
D3 with no floor fill but a bunch of port work. TFS cutter on seats. 1.8" exhaust valve. 214 cfm max.
Decent flowing P-51 research prototype. 1.76" tuliped valve 250 max cfm. Later P-51's max out at 262 cfm.
Out of the box SCJ casting.
Iron cj with typical mid 80's exhaust port work tweeked by RHP

Heads were flowed with 2" primary header pipe 4" straight off of the flange with one 90 degree bend vs the crites #8 primary for the 67 galaxie which abruptly turns down off of the flange and has a 50 degree bend.

Dove straight / crites..... P/C straight / crites....D3 straight / crites... P-51 straight / crites.. SCJ straight / crites... Iron cj straight / crites

.200" 116 / 114..............115 / 113..................107 / 106..........116 / 115...........102 / 101.....................104 / 103
.300" 156 / 150..............160 / 151..................145 / 145..........151 / 147...........139 / 136.....................142 / 140
.400" 184 / 176..............198 / 187..................176 / 174..........178 / 174...........164 / 160.....................169 / 165
.500" 205 / 192..............226 / 207..................201 / 196..........204 / 200...........184 / 182.....................189 / 184
.600" 217 / 204..............238 / 218..................213 / 209..........227 / 219...........197 / 192.....................200 / 194
.700" 224 / 209..............245 / 223..................214 / 211..........238 / 230...........207 / 199.....................207 / 200
.800" 230 / 213..............251 / 226..................214 / 210..........250 / 239...........211 / 204.....................210 / 204



So looking at this, why is the procomp getting such a bad rap......they outflowed everything else tested.....am i missing something......this is from mad prters post on exhaust stuff.....just a copy and past....

Yes Frank you are missing something. All of the above work that Scotty did, was a flow test of the exhaust ports only. You are missing the intake ports and their flow. That's the other half of the equation. If you ask the question which port is more important in regards to making horsepower, the answer is the intake ports. The intake flow of the Pro Comps suffers badly when compared to the other OEM and CJ style heads.

Hope this helps,
Uncle Charlie