Help with ID on this sbb 350

Discussion in 'Small Block Tech' started by 72stage2, Feb 2, 2021.

  1. 72stage2

    72stage2 Well-Known Member

    My son is looking at a buick 350 motor for his skylark but the block casting # is throwing me off 1382201-L serial # 49c119569 engine code on block deck between 1 and 2 plugs RP413 my apologies I'm sure this is old news that's posted but like I said the block casting # is throwing me off. Thanks for your help!
     
  2. 72stage2

    72stage2 Well-Known Member

    Sorry my bad double posted didn't see it up getting to old can't see #^$# with out my glasses
     
  3. alec296

    alec296 i need another buick

    RP is a 350-4 barrel. Should be the high compression engine. 9.4 actual compression. Oil thru rockers/heads.
     
  4. 72stage2

    72stage2 Well-Known Member

    After more digging the block casting was say 1970 but rp engine code was showing 69 GS 350 10.25.1 comp. 280 hp and serial is showing 69. So I was confused with the casting say 70 I'm guessing it must have been late 69 production? So my question is this 350 worth doing a performance build and or goodies?
     
  5. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Depends on what you mean by performance build and or goodies. What are you going to replace/do to it? Pistons, cam, heads, etc?
     
  6. 72stage2

    72stage2 Well-Known Member

    From my understanding some of the 350s you really dont gain much with a performance build and or bolt on stuff like intake or headers for the cost I may be way off base my cars have been 455s so for starters my kid was talking a good intake and headers for this rp code motor and if the heads that came with this block if they are worth some porting and if the have a big valve kit probably a good ta cam to match? It has the original q- jet. Thanks Larry your opinion is valuable to me!
     
  7. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    OK, so basically bolt on stuff. If that's the case, the first thing you want to do is a compression check to determine if the short block is healthy. Given that, there is no way for anyone to predict whether the particular block you are looking at is in good condition. Also, these engines are over 50 years old, so you really don't know if it is all original from 1969-70, it might not be, it might have been rebuilt at some point and then all bets are off. If you intend on putting a moderately sized cam in it, realize that you really should know, not guess, or assume what the actual static compression is as that effects your cam choice. The reason is Dynamic Compression, and I have linked this thread more times than I can count.

    http://cochise.uia.net/pkelley2/DynamicCR.html

    Some guys react to the above article by telling me that is way above their head. My reaction to that is read it and ask questions based on what you don't understand. I mean, that's how we learn right? The biggest mistake performance enthusiasts make is to over cam an engine, and the above linked article details one reason why. The higher the static compression, the bigger you can go on a cam if you want. Obviously, the 1969-70 engines, IF they are original are going to have a higher static compression. The problem is the specifications for static compression that are listed are never quite accurate. A 1970 SS 455 Stage 1 engine is rated at 10.25:1 static compression, it's more like 9.8:1. One reason is that the pistons are .050" or more in the hole at TDC. That makes them more susceptible to detonation on pump fuel.

    So it really depends on specific choices you make and what you intend to do. A later model lower compression block in healthy condition might be a better choice if you intend to stay small on a cam choice than a 69-70 block that is worn.

    I don't think there is that much difference in 350 heads. Most of the compression difference is in the pistons, so any heads are worth porting, again, subject to condition. Have they had previous valve jobs, remember, it's a 50 year old motor.

    For starters, intake, headers? Block condition and ACTUAL compression are what you want to know. Hope that helps.
     
  8. 72stage2

    72stage2 Well-Known Member

    Knew I could count on you! And yes static compression is where you chose best choice of cam. The motor and turbo 400 long shaft was in a 52 GMC pickup. I commend the guy that put in the small block buick!!!! And like you said 52 year old motor chances are at some point you would think it's been freshened up. I do know it ran very strong before it was pulled to do an LS swap. So definitely need to figure out the Internals. But for now a good intake and headers that will fit the 350 in a 67 skylark and possible any board member leads that may have these for sale. Once again Larry great lesson!
     
  9. alec296

    alec296 i need another buick

    The blocks/heads/ crank . Are all basically equal thru all year 350 engines. So bolt ons will improve any engine that is in good mechanical condition as Larry mentioned.
    Combination is where the mistakes happen. Too big a cam, too big an exhaust, to big or small a carb , or improper calibration of carb. Cam not matching compression ratio. rear end gear or torque converter not matching cam and intake.
    the 68-72 have small oil pickup passages. I personally like to have these opened up and get a later big pick up screen. A ta backgrooved front cam bearing will help solve oiling problems and suggest it. If you find the 350 to be in good mechanical condition, and choose to use it as a base, head modifications (bowl porting, blending and big valve )
    Increase potential . Head flow is a limiting factor on this engine.
    I suggest finding some know combinations to follow vs making an assortment of performance parts not matching work together in this engine.
     
  10. 72stage2

    72stage2 Well-Known Member

    Yes you and Larry are right on point! I think for right now with his budget and just buying the 67 skylark for starters he will look for some bolt on parts intake and headers for starters and a good tune. Then he can save some bucks for a decent performance build. What that budget will be not sure but once he figures that out then he can come to the board for build suggestions to his budget. Thanks my Buick Brothers
     
  11. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    If the engine has a 4bbl intake, I would skip that. Headers and a good MSD or other distributor with adjustable mechanical and vacuum advance. Get a good Q-jet calibrated for the engine and you are set.
     
  12. 72stage2

    72stage2 Well-Known Member

    It does have the original q-jet so your saying really not worth doing an intake until he does a build and I'm with you on the distributor tune and carb calibration. Question what headers do we need to look for to go in the 67 skylark with the 350 that will fit right? Thanks again!
     
  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    The only thing an intake will get you is weight reduction, and the ability to run a Holley carb without an adapter. As far as headers, I would call TA. They advertise fit in 68-77 A body, so I am not sure.
     
  14. 72stage2

    72stage2 Well-Known Member

    Thanks again Larry!
     
  15. Mart

    Mart Gold level member

    Looks like you may have a good one there... check the pistons out.
     

    Attached Files:

Share This Page