What’s the biggest cam a stock appearing

Discussion in 'Stock Appearing' started by wildcat4, Nov 23, 2019.

  1. wildcat4

    wildcat4 Well-Known Member

    I am trying to go from headers back to manifolds and I wonder what’s the biggest cam a guy can use when running through the little 2 1/4” hole.
    My 455 has ported stage 1 heads
    10:8 compression (if I remember correctly)

    Thanks for some help
    Rob
     
  2. David Hemker

    David Hemker Well-Known Member

    It's all in the combo. I've seen what is considered very large cams used and I've seen extremely small cams used. You will want to use a large spread dual pattern cam like the factory did to compensate for the less than stellar exhaust flow inherent to the Buick exhaust ports and manifolds. Having head flow data available is important. Matching the torque convertor to the combo is critical. Your exhaust manifolds must have been worked on to get to 2 1/4".
     
    SpecialWagon65 likes this.
  3. wildcat4

    wildcat4 Well-Known Member

    Yes the manifolds were worked on.
    I guess I will just have to try a cam and see if it improves any or not. With no flow numbers on the heads I can only guess. When Gessler ported the heads he suggested 500 to 560 lift max. Currently the engine has a .520 lift 298-298 cam with 21* overlap.
    I assume this is too much but wondered if anyone has seen that work.
     
  4. David Hemker

    David Hemker Well-Known Member

    Do you know the .050 duration specs for the cam that you are using?
    Will you be using street tires or sticky's at the track?
    What stall convertor will you be using?
     
  5. wildcat4

    wildcat4 Well-Known Member

    I want to use the TA 310 cam which I have on the shelf but I don’t have the cam card for it,
    Just hoping I could get by with it.
    I guess I could get those specs by sticking it in a spare block and check it manually.
    32-3500 and a 3:90 gear. I will be using drag radials.
    My car is loaded and weighs 4020 going down the track. It’s not going to break any records but I enjoy it.
     
  6. pbr400

    pbr400 68GS400

    I’m running the 290/94; it’s a little milder (split duration on a 112) and it drives really well. I have 2.93 gears and less stall than you and it ran bottom 13s on slicks. (Hoping with a little more driving it’ll sneak into the 12s). The 310 is a single pattern; I think with manifolds you’d be better off with a split duration.
    Patrick
     
  7. wildcat4

    wildcat4 Well-Known Member

    Right, from what I am learning that is probably what I will have to buy.
    Your car must cruise down the highway without even trying.
     
  8. pbr400

    pbr400 68GS400

    I haven’t been on the interstate with it yet, but driving around town and on country roads it’s really nice. The 455 that was there was very mild and ran high 13s with a stock converter; I drove it regularly and commuted to Atlanta with it fairly frequently. The current engine has more compression, mildly ported Stage 1 heads along with the cam and converter (Hughes GM20BPO). It definitely doesn’t sound stock and seems to drink faster but it now has plenty of power for safe merging and passing. I’d love to see your ‘Cat run BSA in May! Pick Dave Hemker’s brain about your combo. He knows a thing or two, as do Starc Traxler and Bryan Woodworth. Check the BSA threads for more info.
    Patrick
     
  9. wildcat4

    wildcat4 Well-Known Member

    Awesome
    I need all the help I can get. I have been searching through some older threads and learning here and there.
     
  10. wildcat4

    wildcat4 Well-Known Member

    And yes this is all based on getting me into BSA in May
     
    Jim Rodgers likes this.
  11. UNDERDOG350

    UNDERDOG350 350 Buick purestock racer

    I've had good results with Crower cams with wide centerlines in the 350 with iron manifolds. I'll bet they work well in big blocks also. You really want a little more lift and duration on the exhaust side.
    Look at PN 52240
    HIGH PERFORMANCE COMPU-PRO / Performance Level 3
    Intended for the hot street application, these cams offer extended rpm range with emphasis on upper
    bottom and top end power. RPM Power Range: 1800 to 4500 / Redline: 5000 Plus.
    280/286 duration, .488..498 lift on 112 lobe sep.
    Anything much more than that will be choked by the manifolds.
    Mr Hemker has custom grinds made that work very well.
     
    wildcat4 likes this.
  12. David Hemker

    David Hemker Well-Known Member

    The TA-310 cam is 232-232 duration at .050 on 110 degree lobe centers (most likely 106 for the intake and 114 for the exhaust) with .499 lift using stock rockers.
    I'm guessing you might have the TA-298 cam in it now. If so that is the Hemi-killer with 241-241 duration at .050 with a little more lift which as you may know is the cam that the Diabo's used many years ago in round 3 of the GS vs Hemi Shootout.
    Switching to the TA-310 you may notice a little more low rpm power and a little better street manners. In my opinion not really worth the switch.
    To maximize the combo you will need a good dual pattern with 10 - 20 degree's of split at .050 duration.
    The 290/94 is a good cam however your 3200 stall might be a bit much for it.
     
  13. wildcat4

    wildcat4 Well-Known Member

    Ok thanks,
    I noticed an older Lunati cam I have that may be better choice, but would like your opinion.
    253/266 on 109 centerline
    Int. Opens 17.5 @ 50 ext closes 14 @ 50
    .541 lift intake
    .552 exhaust with 1.55 rockers
    Probably too much duration
     
    Last edited: Dec 16, 2019
  14. David Hemker

    David Hemker Well-Known Member

    That is big duration wise. Would work well with your convertor and compression but really needs ported TA heads to work properly. Might be a bit choppy for the idle quality rule of BSA.
     
    wildcat4 likes this.
  15. Thumper (aka greatscat)

    Thumper (aka greatscat) Well-Known Member

    I agree with Dave,from my experience a iron head motor likes a split duration with lots of duration on the exhaust. We run the old KB118 in Sandys X ,I know its old school and have had it in since 1989 but an all around cam that works for both street and strip. Its 228/247 with just under .500 lift on a 118LC. Has plenty of vacuum and a nice lope,want another tenth? the 113 is the same cam but on a 113 LC, less vacuum though. she runs 12.7's at 106mph thru 2 1/2" exhaust,3.42 gears,3000 converter,9.8 compression and mildly worked on iron heads,intake and exhaust manifolds.Its all in the combo.
     
    Mike Nussell, wildcat4 and pbr400 like this.
  16. wildcat4

    wildcat4 Well-Known Member

    Thanks
    I thought about that cam, I do have it but it’s in my other car. I’m probably going to buy a new one since I don’t really want to take it out of a great running engine.
     
  17. Thumper (aka greatscat)

    Thumper (aka greatscat) Well-Known Member

    Sounds like you already have a positive experience with that cam.
     
  18. rkammer

    rkammer '71 GS455 Arctic White

    I had my 455 built to be stock appearing with ported exhaust manifolds (by Jim Rogers) and a Performer intake with the "Performer" filed off the painted Buick red. I custom spec'd the comp cam at 228/237 @ .050 on 115 lobe separation and the motor dyno'd at 468 HP with the stock exhaust manifolds and only 25 degrees total timing due to the builder not setting it correctly. Heads are the T/A aluminum stage 1 (painted red) with stock valve train. Compression is 10.5 and it runs great with 33 deg. of timing (now) on 93 octane pump gas. Goes high 12s at 107 MPH on Radial TAs (not drag radials). Here's the cam card.

    [​IMG]
     
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  19. wildcat4

    wildcat4 Well-Known Member

    Yes I love that old cam!
    Tried and true
     
  20. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

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