Winter project

Discussion in 'Small Block Tech' started by partsrparts, Oct 22, 2020.

  1. partsrparts

    partsrparts Silver Level contributor

    Update. Re-used main and rod bearings, new cam bearings, cam installed and degreed, bottom end back together, measured and ordered 1pc. push rods.
    Only thing left is check valve to piston clearance and set cam end play.
    And alittle porn
    Keith new build6.JPG new build6.JPG new build5.JPG
     

    Attached Files:

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  2. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    Looks sweet ready to rock and roll.
     
  3. Mart

    Mart Gold level member

    Cant tell in pics on my cell,, You opted for a none adjustable std vs 9 keyway roller chainset?
    How tight was that standard link belt chainset since the roller set was so loose??
    Where did cam end up degreeing in at?
     
  4. partsrparts

    partsrparts Silver Level contributor

    It's the 9 key roller chainset. the chain is tight, as it was the last time when installed at first
    Straight up at 112
     
  5. partsrparts

    partsrparts Silver Level contributor

    Started it up for the first time sat., 40lbs oil pressure @ 1,000rpm. Let it run for about 15min. to get it warm and then shut it down to cool off. Gotta love the sound of those roller rockers!
    Sunday re-torqued the intake and valve covers.
    Today put the front clip back on except for hood,(makes it a lot easier to work on the engine without it in the way).
    Tomorrow I will take it down and put fresh gas in it and then start tuning. It will be interesting to see how much difference there will be in the tune between the two set ups. Flat tappet, dual plane, stock iron heads to roller, SP3, alum. heads.
    Keith
     
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  6. Mark Demko

    Mark Demko Well-Known Member

    Hurry up:p
     
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  7. partsrparts

    partsrparts Silver Level contributor

    Went and put fresh fuel in, if you try to give it any real throttle it goes instantly lean,(AFR meter will flat line). You can ease into it ant keep the AFR around 13.0-13.5, idles at 12.8, light throttle, cruise is in the 13-14 range which is fine, I don't care about fuel mileage.
    Jets are 66 front, 73 rear, #35 squirters front and rear, pink cam on #1 hole front and rear, power valve a 6.5 I believe. Can't tell by the AFR when the power valve kicks in
    I will double check all tomorrow. Plan on disconnecting secondaries and just tuning primaries first.
    Keith
     
  8. sean Buick 76

    sean Buick 76 Buick Nut

    Did you adjust the idle mixture screws?
     
  9. Mart

    Mart Gold level member

    Which carb?
    Did you pop pistons out, hone and re-ring?
     
  10. Mart

    Mart Gold level member

    Hey, another dual plane for sale for somebody.:D:D:D
     
  11. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    66 jet does not seem like enough. if it is a Holley It should be around 70-77 or 70-75 0r 69-75 something like that You have list number on air horn I have Holley book with list numbers. Actually numbers all over the place just depends on what carb you have.

    Most of the primary squirters in my book are from 25 to 31 but it does depend on what carb but that is the general range.

    At 6.5 on the power valve is when the valve will open at that vacuum. You would have to use a vacuum gauge and try and look at that and the AFR gauge at the same time to know if the enrichment came in and at what number on the AFR. Too much to look at would need to record it.

    If you do disconnect the secondaries just do the part throttle like about half way to see how the response is. Floor it from dead stop and see if the squirter up front is enough. You probably need to just go a couple hundred feet to tune this part. After that you need the secondaries to bring it on thru. Then go put in CD or Stick, Deep Purple in Highway Star and go out and rip some rubber!
     
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  12. partsrparts

    partsrparts Silver Level contributor

    Really no adjustment needed from where they were from before according to vacuum gauge

    Holley 750DP 4 corner idle. Engine only had 10,000mi. on it, pulled pistons, cleaned pistons and re-spaced end gaps. Still had good cross hatch.

    I have 2 #37 squirters I can try also. Do the little brass nipples on the squirters do anything?
    I will also change jets up if I can't get anywhere on the squirters.
    Tried watching both, the vacuum gauge is in the dash and the AFR is under the dash.
    Keith
     
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  13. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    You probably will never see the AFR gauge change when the power valve opens I wouldn't worry about that part. Just do the part throttle cruise and when it is on the floor the rest is pump shot and such.

    The brass nipples just help to direct the gas to the venturies more that is all, It may or may not help with bog, they are supposed to be better.

    Your 750 should have a 70 in the primaries It could be bogging since the primaries are not big enough.

    The jet is taylored to the venturies in carb and should not be very far from original setting I would not go lower than a 68 on primary. you got to remember this is your part throttle cruise and should not be lean during this time.

    You have a list number on top of the air horn what does it say?

    The 37 is probably going to cause it to flood and that will seem like a bog. This is why I need the list number you need to go back to its' original jetting and go from there. Originally it probably had a 28 up front and a 31 in the rear
     
  14. Mart

    Mart Gold level member

    Ran 78/91's on my old 750, 6.5 p.v., think 37 squirters. 66 is small. Think stock jetting is abt 72/80.

    No Ridge at 10k miles?
     

    Attached Files:

  15. Mark Demko

    Mark Demko Well-Known Member

    All 350 Buicks should have an SP3
    The 350 Buick is a torque beast amongst small blocks
    The SP3 kills little if any low end torque.
     
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  16. Mark Demko

    Mark Demko Well-Known Member

    Shouldn't be any noise from the rockers:eek:
     
  17. partsrparts

    partsrparts Silver Level contributor

    I found the original settings for the carb and put it back, 71 primary, 80 secondary, 28 front squirter, 31 rear, 6.5PV.
    The difference was day and night, solved 95% of the issue. Still a slight hesitation but nothing like before. 60mph cruise 12.8-13.2 AFR, 40mph cruise 11.8-12 AFR. 40mph, 3rd gear 1800rpm to WOT slight hesitation 12.8 AFR.

    Just slight carbon ridge, came off with brake clean.

    Actually seems to be sound from valves slamming shut, removed valve cover breather cap and sound did not change and seems sound is coming through the carb. With air cleaner on the sound is a lot quieter.
    Keith
     
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  18. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    Great! now just use knowledge and try different shooters or the pump cam. Do only one at a time and if that don't work take that part back to original setting and try the other. May need a combination of both to get your tip in and a romp to the floor, just work on one at a time now and your on your way.
     
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  19. partsrparts

    partsrparts Silver Level contributor

    21build2.JPG HOLY CRAP! Put it in 1st at a stop and slammed it to the floor, about a half second hesitation and then rpm's climbed so fast didn't get a chance to look at tach before I had to shut it down. Thought for a sec. that maybe trans was slipping except for the rear wiggling a little and the smell of burnt rubber!! This thing rocks!
     
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  20. Dano

    Dano Platinum Level Contributor

    That's awesome!
     
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