Advice on limitations with compression

Discussion in 'Small Block Tech' started by chris sworik, Mar 1, 2021.

  1. chris sworik

    chris sworik Active Member

    Hi everyone. Back again for some advice. Been searching the SBB thread for quite some time. My head is spinning with SCR, DCR, camshafts and just about everything else. Just to refresh everyone, I have a 72 Skylark which I removed the heads to do some cleaning and mods. I thought 72 heads were a strange head since everyone talks about 68-71 heads and I was doomed. Went to my stockpile to find the alternative 71 engine was siezed. OK, took heads off this engine and compared it to the 72 and saw the only visible difference was the AIR holes. (Yes, casting #'s, year on exhaust horn were) Everything else looks the same. I have a few questions some basic some maybe not. First off, most of the links in the sticky or first posts come up as an error, cannot be found. I remember the site was compromised and many posts destroyed. Is this true or am I doing something wrong?
    Not sure what everyone means by double scallops. It's all 455 posts. No pictures etc. I think it is two coolant passages in the middle of the head.
    Heads are off and I am going to drop them off at machine shop for cleaning and check for cracks.
    The heads off the 72 do not have spring dampers on exhaust springs. Has someone been working on these prior? Did 72 have dampers like other years?
    Looking at possibility about replacing the cam. What kind of SCR will I require for a Crower Level3. Hear lots of good talk about it but don't know if that is a possibility without changing pistons. 91 octane fuel here. Not sure if this can be accomplished with head or block decking. Or, is a Level2 more practical.
    Have plenty more questions but do not want to go overboard on the first post. Thanks, Chris.
  2. sean Buick 76

    sean Buick 76 Buick Nut

    Yes I need to try to fix a lot of the links in the sticky’s. The v8 board got re formatted and it screwed up the links.

    I wouldn’t be too worried about which year heads you are using. Yes the 72 and later heads should have the Center cooling port that was added to eliminate the cracking the 68-71 heads are prone to.

    yes you should stick to the milder level 2 cam unless you want to replace the pistons and in that case the level 3 is fine with a true 10:1 static compression ratio. Right now you are at 8:1 and milling the heads and block too much just cost $ and creates intake manifolds fitment issues.
  3. alec296

    alec296 i need another buick

    The crower level 3 will make decent lower and mid power , just mill your heads .030 for about 50 cc head. Stock is only about 8.2 measured.
    That will net about 8.75 scr and 6.72 dcr. If you advance the cam 4 degrees. Add a 22-2400 small block rated torque converter. Then it’s all about tuning. A different year distributor would be good also. 72-73 can be lacking in full advance. you will see the extra coolant ports circled in pic
    I would change front cam bearing while your there. Save the headache of low hot oil pressure

    Attached Files:

  4. chris sworik

    chris sworik Active Member

    I really appreciate the info guys. The picture is exactly what I thought it was. Strange but my 72 does not have those cooling passages. Maybe an early production date, A5 and A26. I see you may have blocked your cleanout holes. Is there an advantage to doing this? Currently in limbo until I get the heads to the machine shop. Just want to know they are good to go with no cracks. (they are the only heads I ever had no exhaust bolts break on. lol) One question though, how much can I deck or machine heads until I need to get resized push rods? Thanks. Chris.
  5. alec296

    alec296 i need another buick

    Yes could be an early production engine. . No clue on the blocked ports. This was not my engine. Just needed the picture.
    I believe.030 is about the most you can get milled before pushrods are an issue due to lifter preload. And every engine is slightly different, so you may still see something at .030. But the rocker arms and shafts may have some wear. So then your just making up for wear.

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