h/o guy

Had a customer come to my shop with a 75 Cutlass that has a 350cid engine with several components purchased through the above noted vendor.


One of these items was the top end package utilizing the Pro Comp cylinder heads, roller rockers, pushrods and related items.


This vendor sent out the "out of the box" heads to another machine shop be milled for the small block combustion chamber but never cc'd a head to properly figure out how much to mill. The heads were only milled about approximately .050- .060 so for those of you who know ( and for those who don't) that was only about half as much as is needed to be even in the ballpark for a proper compression ratio.


These heads as assembled are simply slapped together at Pro Comp and are not checked for proper guide clearance, seat to valve face contact, valve stem height, valve stem quality ( nicks and burrs) etc but they are advertised as being identical to what the "Bog Boys" sell which is far from the truth.


This vendor also sent the package out with the Pro Comp push rod guide plates which are ok to use for 3/8 push rods but never explained to the customer that when installing them, there is a built in offset to them for aligning the push rods / rockers so six of the eight were installed incorrectly and the rockers were riding on the edge of the vale stems.


Lastly the Pro Comp roller rockers that were supplied were not even close to having proper valve train geometry nor were the pushrods the right length.


I wanted to point this out because many may see a big difference in price between this vendor and some others out there that also sell Pro Comp heads but do so for more money and there is a reason, its called paying attention to detail!. The Speedmaster / Pro Comp casting is a good product, but the components and prep that are put into them is sub par and should be addressed before your hard earned money that is spent on your engine build is wasted with a severe failure and the need for a full rebuild as is the case with this customer we are helping.


Feel free to email me or pm directly if you want further input / suggestions on this scenario or other Olds components you are considering.


Grant

h/o guy

Correction on spelling...."Big Boys"...

83hurstguy

That's why you pretty much always throw out the low ball bid. They're either working for free or cutting corners...

From what I've heard, that vendor is an ex-Mondello employee (or so the story goes).

Classics65

I purchased the speedmaster heads knowing the risks. Before I did anything with them I had my local machine shop check all the valve guides and seats. Came back good from the machine shop. Hoping I can get my 468ci on the dyno the winter/spring for break in so I will know the true value of the heads I purchased then. But if all run well it will be a a pretty good deal for the price even with the machine shop once over. Just like any major component likes a cylinder head/engine block etc it's always good to have a machine shop or engine builder double check everything

olds 307 and 403

Doesn't .006" equal 1cc on Olds heads? I believe Mark said they actually measure 77cc out of box. That should put them in the 67cc range. I plan on buying mine bare and adding Edelbrock valves and whatever springs and about a .060" cut for that 67cc chamber size.

h/o guy

I suggest you have those heads cc'd before deciding how much to cut. I can tell you the chambers are larger in most cases than what is advertised.

olds 307 and 403

I would cc before cutting. I know people were saying 83-84cc when they first came out. What did this "64"cc set actually measure?

70W-32

Jr., I dont think he's actually an ex employee, just operating out of a different address so people dont realize its still Lynn. Thats my understanding.

If someone isnt going to have the heads checked after purchase, they should buy from Bernard Mondello

h/o guy

Just an update on this post, I finally had Bernard Mondello cc these heads that came from OldsRocketParts.com and one head came in at 71cc and the other at 72cc so not even close to the advertised 64cc.


Feel free to go to Bernard's Face Book page and see the results and his input on this.


If you are buying parts, machine work, or complete assemblies of any kind from Jr. or for that matter from Lynn at MPP you will be spending that money again and then some with a reputable builder so consider that when you see that "deal" being advertised.


Grant

gs72

thats a shame. That dual plane air gap Intake manifold they sell looks like a good deal. Has anyone here used one?

70W-32

Its made in China, and I see them forsale second hand all the time. Doesnt matter how good a deal if you have to sell it later and buy the American made version.