Don Terrill’s Speed-Talk

I am building a 598 Merlin3 with a eagle forged rotating assembly.
I am on a very very tight budget and found a set of pro comp 360
heads that are pre assembled.
I had some people say that if i replaced the springs and small parts
that i could make a decent set of heads. They say the valves are ok.
If anyone has any info on these heads please let me know.
Thanks R.C.

I had a set in here last fall. They wouldn't be my first choice. The customer only drove his car one day and it was slower than his stock iron heads. It took a lot of work to get them close to right. Replaced all the hardware. The exhaust guides were off center on the valve seat and were worn to an oval in about 10 miles of driving. I had to replace the exhaust guides. (the reason for it being slow, none of the exhaust valves were seating)They were an odball size, .506 and I couldn't find them anywhere. I bought some larger ones and cut them down. All the rocker studs came with heli-coils and some of them had to be replaced as they were hanging down in the intake port half unwound. They did make some decent power, 800 hp on an E85 496. You would be money ahead to just start with something better.

Thanks for the info. What if i bought them bare and had the heads worked at a shop?
I could get them cnc ported at the same time.
R.C.

I got a set of 781 stock cast could i have them worked.
I also got a guy who has a set of 781s that have 225-188
that already has some port work done to them.
R.C.

598 BIG RAT wrote:Thanks for the info. What if i bought them bare and had the heads worked at a shop?
I could get them cnc ported at the same time.
R.C.

WAIT A MINUTE ! you can afford to have them re-worked ( 4-500 dollars) and have them CNC PORTED ( 1000 DOLLARS) ......BUT can t afford a set of 2300 dollar BRODIX,AFR,DART heads READY TO GO !!! ???????????????????????????????????????


DOESN'T ADD UP AFTER THE PURCHASE PRICE OF THE PROCOMPS(600 DOLLARS) !

jason snyder wrote:

598 BIG RAT wrote:Thanks for the info. What if i bought them bare and had the heads worked at a shop?
I could get them cnc ported at the same time.
R.C.

WAIT A MINUTE ! you can afford to have them re-worked ( 4-500 dollars) and have them CNC PORTED ( 1000 DOLLARS) ......BUT can t afford a set of 2300 dollar BRODIX,AFR,DART heads READY TO GO !!! ???????????????????????????????????????


DOESN'T ADD UP AFTER THE PURCHASE PRICE OF THE PROCOMPS(600 DOLLARS) !

X2 and if you go to sell them years later you likely get more $ for the name brand heads

Save your money.
Buy a quality set the first time.
You will be miles ahead.
Buy the PC heads and eventually you will wish you had saved up for the quality piece.
It is not the power producing potential. It's everything else.
Heads are certainly not the area to cheap out on a performance build.

Support your local USA Co.s. we need to keep them around.
ARN

jason snyder wrote:

598 BIG RAT wrote:Thanks for the info. What if i bought them bare and had the heads worked at a shop?
I could get them cnc ported at the same time.
R.C.

WAIT A MINUTE ! you can afford to have them re-worked ( 4-500 dollars) and have them CNC PORTED ( 1000 DOLLARS) ......BUT can t afford a set of 2300 dollar BRODIX,AFR,DART heads READY TO GO !!! ???????????????????????????????????????


DOESN'T ADD UP AFTER THE PURCHASE PRICE OF THE PROCOMPS(600 DOLLARS) !

i don't have 2300 at this moment.

A Atwood wrote:Save your money.
Buy a quality set the first time.
You will be miles ahead.
Buy the PC heads and eventually you will wish you had saved up for the quality piece.
It is not the power producing potential. It's everything else.
Heads are certainly not the area to cheap out on a performance build.

Support your local USA Co.s. we need to keep them around.
ARN

I have been trying to find a good used set ,but who do you trust.
SAVE SAVE SAVE
R.C.

598 BIG RAT wrote: i don't have 2300 at this moment.

Then stop right now and save the lunch money to get quality heads.

Even the aluminum used on those Pro Craps is worst quality possible.

If the money is really tight, get a stock set of retangular ports and port them yourself. Put new guides & valves and run it.

here you go ! http://westernmass.craigslist.org/pts/3564107377.html

or these ? http://lexington.craigslist.org/pts/3552540436.html

BrazilianZ28Camaro wrote:

598 BIG RAT wrote: i don't have 2300 at this moment.

Then stop right now and save the lunch money to get quality heads.

Even the aluminum used on those Pro Craps is worst quality possible.

If the money is really tight, get a stock set of retangular ports and port them yourself. Put new guides & valves and run it.

What about the 781 ovals would they be worth a re-ground and valve job. I dont even know what valve is in the 781s

R.C.

I built a friend a 427 with 781s. Street motor 10:1. Runs 11:90 on motor 10:90 on spray. Stock 2.080 1.720 valves.I looked at one of those Ebay 541 motors with Pro Comp heads. The valves are pretty far out of line with the studs and push rods on the intakes causing the rocker to be off to the side of the valve way off. The guy he bought it from told him to take a hammer and bend the stud until they lined up. He said he didn't have time to make all of that stuff right for the price he got. And one more thing Pro Comp and dependability don't even belong on the same page!

robert1 wrote:I built a friend a 427 with 781s. Street motor 10:1. Runs 11:90 on motor 10:90 on spray. Stock 2.080 1.720 valves.I looked at one of those Ebay 541 motors with Pro Comp heads. The valves are pretty far out of line with the studs and push rods on the intakes causing the rocker to be off to the side of the valve way off. The guy he bought it from told him to take a hammer and bend the stud until they lined up. He said he didn't have time to make all of that stuff right for the price he got. And one more thing Pro Comp and dependability don't even belong on the same page!

you know uaually when people are diskin equipment someone in the growd has some good experiences,not in this case. I thought as long as they have been making these heads they would have improved them by now.
they seem to have improved on the pistons and rotatting equipment. (or have they?)

R.C.