PROCOMP sbc cylinder heads

[Red]

Hi Red, nice to see the photos you took of the Patriot heads at the Murray's Speed and Custom. These heads are as you indicated not CNC ported, but just gasket matched, probably by hand. I have not inspected these cylinder heads myself, but it seems like they have a reasonable flow as cast for mild street engine builds. I’ll try to do some work on my PROCOMPs next week and hopefully I have some more information to post as I progress. If you have some more information about the Patriots Red, I’ll appreciate sharing your findings.

As for the roller cam; I don't think that the 3970010 block is well suited for such. I would choose a flat tappet cam to be safe.

Arne

I never did get to see the Patriot head valve pockets, but think thay have been ported. After talking with a few other engine builders, they say the CNC porting is OK for FI cas, as the spray amomizes the fuel. Carburetors need the rough tool marks to help in this process. The CNC porting is too smooth for a carburetor fueled car. I'm going to look into this some more. Sometime in October I should be ready to buy my heads.

Recently, I spoke with a CF member who built his original 73 Corvette two bolt block using a cast crank, Edel 64 cc 170 heads, CC roller cam .510 and Holley 750 carb. It was dynoed at the builders shop to make 440 HP. My high nickle 010 four bolt block should do similar with a more aggressive cam and 190 runners in the heads. The two piece MS block will take a roller cam if you use the more expensive bar type roller lifters. My block will be decked, just like the engine built by the member and used as an example. It runs fine on 93 octane PG with a 10.25 CR. This is my plan, but anything can happen. Right now I'm still trying to fully understand the work done on the Patriot heads I'm looking at. I need to see the valve pockets. If it isn't fully ported, I may just do a set myself and save a little money.

A concern with porting an aluminum head is removing too much material. Aluminum comes out real fast and that is my fear. I've done iron heads with great results. My experience with aluminum, using my aluminum burrs, has been scarry. Maybe, it was just a soft alloy, but it was gone in a flash.

 

[jsssgrl1209]

CNC porting.

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. .




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!

 

[arneoe]

If you go for the Patriots, I think they'll work quite well as cast ....and you'll not gain much from hand porting. The Patriots dry flow numbers in low/medium lifts will be more than sufficient for mild street builds. Find your self a cam that will be a good combo with your cylinder heads and CR.

Red, start a new thread here on VM about your project and you'll get good help from the real experts. ... At last, just a friendly Warning to you; don't post positive remarks about Patriot cylinder heads on CF.... I have nasty exprience!:rofl:
Good luck

Arne

 

[arneoe]

Just some information of intrest.... I found on YouTube .... for porting the PROCOMPs and other heads. On my PROCOMPs I did not find much imperferctions inside the runner and I think they were big anought for my use as is, but anyway:

[ame]http://www.youtube.com/watch?v=JmOc7xOLqsM[/ame]

Arne

 

[Twin_Turbo]

He talks about the intake port and says "where the bolt goes through" that's not where the bolt goes through, that ridge is from the pushrod hole. It's real easy to break through there.

Real porting is not just cleaning stuff up and hogging stuff out or port matching, it's reshaping the port and bowl contour to improve flow in such a way that it suits your engine. Usually this involves reshaping the short and long side radius and port roof as well as minor port floor work and work on the port to bowl transition. Often modifying the port bias to the side of the bowl to more efficiently swirl the mixture past the valve. That's the real trick where it concerns the transition from port to bowl, getting the mixture to swing past the port and then also reshaping the chamber to the bore diameter to reduce valve shrouding.

He says there's nothing scientific about it but really..there is and it's very easy to f-up a head and make it flow worse. If you don't know what you're doing, just clean the port up, smooth it out and work the bowl and guides and leave it at that. Professional porters have learned from a lot of trial and error and testing, it's as much magic as it's science.

 

[Red]

Just some information of intrest for porting the PROCOMPs and other heads. I did not find much imperferctions inside the runner on my heads and I think they were big anought for my use as is.

http://www.youtube.com/watch?v=JmOc7xOLqsM

Arne

It sounds like you have put a lot of thought into porting your heads. What you have done looks good to me. For a street engine you will be way ahead of most guys who just bolt on a pair of untouched heads and go. The serious racers wouldn't use those heads anyway, runner volume is too small, and have way more tools at their disposal for porting than 'shade tree mechanics.' They are fighting for every last HP in a heads up racing environment.

I did exactly the same as you, making the exhaust port slightly larger than the gasket and solved it the same as you, but on iron heads. Blending the valve boss is an important part of the job and I thought you demonstrated it well. Thanks for taking the time to illistrate what needs to be done in a basic port job. The best I can do is provide some fuzzy photos, but I will try and take some after buying my Patriot heads. You had to unleash some free HP as a result of your effort and that's the idea.

 

[Bee Jay]

I'd be really interested to know how these "Chineese" heads compare to stock GM heads. sometimes it takes $400-500 of machine work to restore factory heads. These have new valves, new guides, new keepers, and they are aluminum. The "Japaneese' used to make perfect imitations of the original. I wonder what the Chineese heads used as a mold?
Bee Jay

 

[Twin_Turbo]

Stock GM heads are thin castings with thin decks, small chambers and small valves. The L98 head won't even accept 2.02 & 1.6 valves, they simply don't fit the chambers. Not saying the Chinese heads are better but GM heads aren't all that either.

 

[Bee Jay]

Stock GM heads are thin castings with thin decks, small chambers and small valves. The L98 head won't even accept 2.02 & 1.6 valves, they simply don't fit the chambers. Not saying the Chinese heads are better but GM heads aren't all that either.

So, in your opinion, it's better to spend $400-500 on a set of these heads instead of spending $350-450 to rebuild a set of iron oem heads?
Bee Jay

 

[Twin_Turbo]

Iron heads? Yes, certainly. I figured you were talking about aluminum heads.

 

[arneoe]

For those who want to look closer into a SBC budget engine project, using affordable offshore :chinese: alu heads, may find a lot of interesting information in the October issue of SUPER CHEVY. In the article THE CHUMP CHANGE CHALLENGE on page 064, they have built a 400hp 350 street engine for approx. $1000 of total spending, using a set of brand new PROCOMPs 190cc (#3002). These are as cast and compared with L98 stock heads the PROCOMPs flow far better up to .600 lift. From the measured low lifts flow of the 190cc PROCOMPS, a swap from stock iron to alus (together with a suitable cam) will significantly increase torque and hp in the usable rpm band for street use.

For my own 383 build, there has not been much progress the last three weeks, there’s much work to do outdoors before we have the first snow.

best regards
Arne

 

[JAKE]

A few months back when I was head hunting, my first, over-riding concern was the actual spec of the aluminum used in the casting.

Was there any indication of the aluminum spec? Re-cycled beer cans wouldn't be my first choice, LOL.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

 

[arneoe]

A few months back when I was head hunting, my first, over-riding concern was the actual spec of the aluminum used in the casting.
.....

Very interesting subject.... please inform us which specific technical specifications have been your requirement for the selection of cylinder heads? And finally which brand and type did you chose?

Arne

 

[Red]

For those who want to look closer into a SBC budget engine project, using affordable offshore :chinese: alu heads, may find a lot of interesting information in the October issue of SUPER CHEVY. In the article THE CHUMP CHANGE CHALLENGE on page 064, they have built a 400hp 350 street engine for approx. $1000 of total spending, using a set of brand new PROCOMPs 190cc (#3002). These are as cast and compared with L98 stock heads the PROCOMPs flow far better up to .600 lift. From the measured low lifts flow of the 190cc PROCOMPS, a swap from stock iron to alus (together with a suitable cam) will significantly increase torque and hp in the usable rpm band for street use.

For my own 383 build, there has not been much progress the last three weeks, there’s much work to do outdoors before we have the first snow.

best regards
Arne

Thanks for the heads up Arne!

 

[JAKE]

I'm not by any means a guru when it comes to metals but I suspect most of us know that aluminum cylinder heads are not cast from pure aluminum. They're an alloy, meaning there are other trace metals present in certain, rather precise, percentages. Metals like copper, magnesium and silicone, etc. come to mind.

These trace metals make the finished product more suitable for certain applications than others. Cylinder heads, that are exposed to all sorts of stresses and temperature changes, require a certain percentage of trace metals be added to the "aircraft grade" aluminum to give the best performance when used as cylinder head castings.

I like to see, at least, that words "aircraft grade" aluminum is shown in the ads along with the heat treating spec. From the research I did on this C355-T61 seems to be the spec touted as being best for cylinder heads.

Bottom line is, when I read an ad that makes no mention of the casting material spec, my suspicious meter goes up. What comes to mind is the rash of inferior/often breaking bolts that came out of China a while back. Makes me wonder if heads cast in China aren't being cast from old lawn chairs.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

 

[mrvette]

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 **** that the next one is....

:shocking::beer:

 

[arneoe]

According to my US supplier, the the PROCOMs are of aircraft grade A356 aluminum alloy heat treated to T-6 specifications. I do not think that this is of much inferior spec to the C355-T61, which is used by DART.

http://www.dartheads.com/ftp/C355-T61 Aluminum Alloy.htm

If we leave politics for a minute, I see reasonable good quality machined cylinder heads resting here on my work bench. I have published close up pics in this very thread .... and this should prove this.... just see for your self and compare with the GM iron smog maidens which they are to replace. And again, I have no agenda with this, but I see what I see .... these PROCOMs are very well suited for my 383 mild and modest street build.

Arne

 

[JAKE]

According to my US supplier, the the PROCOMs are of aircraft grade A356 aluminum alloy heat treated to T-6 specifications. I do not think that this is of much inferior spec to the C355-T61, which is used by DART.

http://www.dartheads.com/ftp/C355-T61 Aluminum Alloy.htm


Arne

Whatever floats your boat. Compare the differences between the two and choose your poison.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

 

[Twin_Turbo]

And the dart stuff is cast from fresh ingots, you can bet your azz that the Chinese stuff is made from recycled soda cans

 

[MYBAD79]

Here's some good info on aluminum:

http://materials.globalspec.com/Spe...errous_Metals_Alloys/Aluminum_Aluminum_Alloys

Now, since we're talking about a casting and material quality.... the stock cast iron heads often crack, can these chinese aluminum casting really be worse than the crap that came on these cars ?? I think as long as there are no voids in the casting it should be fine.... did anyone x-ray their chinese SBC heads ??? That could reveal some very interesting details.... LOL

 

[Finn]

I find it tiring that the product is referred as Chinese as they are, to my understanding, Australian by Pro Comp from Victoria, Australia.

If these heads are Chinese then my American Racing Hopsters, which arrived yesterday, are Chinese, too, since that's where they are manufactured now.

 

[JAKE]

I don't know where the heads were cast, that wasn't even my point. In my research for sa set of heads to buy, I simply wanted to know from what they are cast.

Absence of that information makes me curious about not only the casting material being used, but also why no mention is made of the material. This applies to ALL the heads I looked at, not just yours. It's a question, not an accusation.

When I was searching the different LT1 cylinder head offerings I looked to see:

Would they fit my application (LT1), then

Company's reputation then

What material they are cast from, then

Combustion chamber size/port volume, then

Valve sizes then

Installed springs then

Flow numbers, then

Any special, non-stock parts needed, then

Cost, then

Availability, then

Any dyno comparisons/results then

Feed-back from those running those heads.

Just how I did it, pretty much in that order.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

 

[arneoe]

I find it tiring that the product is referred as Chinese as they are, to my understanding, Australian by Pro Comp from Victoria, Australia.

If these heads are Chinese then my American Racing Hopsters, which arrived yesterday, are Chinese, too, since that's where they are manufactured now.

Tjanare grabben! :friends:...

Sure:chinese:, but I think they still make wonderful wheels, regardless:
http://www.jalopyjournal.com/forum/showthread.php?t=263034

You'll find the point of contact for the PROCOMPs offered in the States here:
http://sydneyspeedsupplies.com/

Arne

 

[Finn]

Tjanare, Arne. :drink:

 

[BRUTAL64]

Just a point of interest here. I bought a set of CHEAP China heads from a back east no name company. I just wanted to try a set to see if there would be a major difference between iron and alum heads for compression ratios.

I do my own porting, so that is not an issue. So anyway---I put five hours of porting in to each head and bolt them on. That was over 2 years ago and NOT one problem with them. I run my MULE motor hard.:beer:

 

[arneoe]

Just a point of interest here. I bought a set of CHEAP China heads from a back east no name company. I just wanted to try a set to see if there would be a major difference between iron and alum heads for compression ratios.

I do my own porting, so that is not an issue. So anyway---I put five hours of porting in to each head and bolt them on. That was over 2 years ago and NOT one problem with them. I run my MULE motor hard.:beer:

Very interesting David. Do you have more spesific details about your cylinder heads? I think I recall they are PROCOMPs, like the ones in your avatar.

Arne

 

[arneoe]

I don't know where the heads were cast, that wasn't even my point. In my research for sa set of heads to buy, I simply wanted to know from what they are cast.

Absence of that information makes me curious about not only the casting material being used, but also why no mention is made of the material. This applies to ALL the heads I looked at, not just yours. It's a question, not an accusation.

When I was searching the different LT1 cylinder head offerings I looked to see:

Would they fit my application (LT1), then

Company's reputation then

What material they are cast from, then

Combustion chamber size/port volume, then

Valve sizes then

Installed springs then

Flow numbers, then

Any special, non-stock parts needed, then

Cost, then

Availability, then

Any dyno comparisons/results then

Feed-back from those running those heads.

Just how I did it, pretty much in that order.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

That seems very well organized.... and which cylinder heads did you end up with Jake?

Arne

 

[JAKE]

I don't know where the heads were cast, that wasn't even my point. In my research for sa set of heads to buy, I simply wanted to know from what they are cast.

Absence of that information makes me curious about not only the casting material being used, but also why no mention is made of the material. This applies to ALL the heads I looked at, not just yours. It's a question, not an accusation.

When I was searching the different LT1 cylinder head offerings I looked to see:

Would they fit my application (LT1), then

Company's reputation then

What material they are cast from, then

Combustion chamber size/port volume, then

Valve sizes then

Installed springs then

Flow numbers, then

Any special, non-stock parts needed, then

Cost, then

Availability, then

Any dyno comparisons/results then

Feed-back from those running those heads.

Just how I did it, pretty much in that order.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

That seems very well organized.... and which cylinder heads did you end up with Jake?

Arne

Dart Pro 1s. Advertised at 180ccs but I, (and others) cc'd them at 189.5. 58cc chambers and I went with thin head gaskets to keep the a CR up. I swapped to 7/16" ARP studs and used Scorpion 1.7/1.65 RRs.

Cost and Availability knocked AFR Eliminators out of the running. The Dart's were $1,350 which included the shipping from JEGS and I received them in 3 days.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!

 

[arneoe]

Here is my first dyno simulation printout. It seems to me that my goal for a high torque engine is quite close with this combo. I have done very little to the runners, just gasket matching as described in my earlier posting. I am a little concerned about CR, but I estimate around 10:1 will do.

Arne

 

[76BluRay]

any more updates?