I kind of figured the Olds was already installed. Just inquireing about the year.
Really, I have never heard this before, interesting. Guys have milled Olds iron and aftermarket heads as much as .100". It is needed to run the BBO or Procomp Aluminum heads on a 350 and get any sort of compression. Of course those heads need port work to flow. Another thing guys have done is mill the intake less than the heads and raise the roof of the port, Olds has a very flat 6 degree valve angle. The Procomp heads will go on my 350, milled and CNC ported if Edelbrock can't get their *ss in gear and release the new 68CC aluminum this Summer. They also need to make the Olds RPM intake available, needed with those heads. It won't surprise me if that current Olds 350 is healthy enough to put early 350 heads on. They were much better than the sbc for durability from that era, just super choked at 165 HP. Mill the early heads to 64cc, they are probably 68 to 70CC as cast. Otherwise you are only gaining half a point of compression going to early heads. Pistons sit .025" below deck and Felpro head gaskets are .042" compressed vs .017" for the factory shim gaskets which are no longer available. Same goes for early motors, don't swap head gaskets. The thinnest available head gasket is the expensive Cometic MLS available in .027", the rest are .038" to .045". The nylon coated cam gear timing set and under 200 duration and .400" lift peanut cam should be replaced. Also use the OS30471C pan gaskets and either the 292 Ford or AMC 252 rubber rear main seal in place of the rope seal. Good luck.If you are going to change the heads, do not mill them anymore than needed to make them square. Flat milling for compression is worse for airflow. Airflow makes more power than a couple of tenths of compression. Going from 79 to 64, that will help. But someone mentioned 68, if that is what they are leave them alone.
Yada yada yada...If you have the money look into a website called oldsparts.com, the guy will answer any question and usually has all his parts in stock. I've bought an oil pan and pickup, distributor, spark plugs and wires from him and soon to be pistons all for a very reasonable price. He even sells Procomp BBO heads already milled for a SBO and a matching intake manifold at a reasonable price, I've heard a lot about the setup being good and the compression would be at 10:1 if I remember correctly but I didn't buy it because I don't have that kind of money right now and my 7a heads are already 64 cc and I'm having 2.07 in intake valves installed. But I would never go LS, IMO it's overrated but I'm die hard Oldsmobile to the point where my project is my 1982 Cutlass and my daily is a 1998 LSS.
Go open your door and put head between the jamb and door and slam it hard three times. This will be your experience with Brothers except you will still have your money.
Which is exactly why I use Mark Remmel, a one man operation. It take time for Mark to get quotes and parts out these days. https://newoldsperformance.com/Yada yada yada...
All fine and good until YOU have an issue with something, like one of those aftermarket pieces that doesn't fit....it's YOUR fault if it doesn't fit.
I made the mistake from giving him money for his garbage years ago. Never again. I'm not the only story, either, so take it for what it's worth. Anything he has you can get elsewhere, and I advise you get it elsewhere if possible. If he's changed his business practices for the better, then that's good for someone. I'm still never going to chance that again.
It used to be Brothers Automotive. If anyone's familiar with that, you know what I'm talking about. Would put a PICTURE of a warehouse he didn't even have on the catalog for illustrative purposes only, apparently. SMDH.
Here's a quote from someone else that sums it up better than me.
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