1st track testing of the alum 350 head on this forum

Discussion in 'Small Block Tech' started by partsrparts, May 17, 2021.

  1. partsrparts

    partsrparts Silver Level contributor

    Finally made it to the track. Fri night test and tune was rained out. Sat bracket race was 2 time trials then eliminations.
    Off the trailer, 1st pass with this combo, 20lbs in the MT drag radials, stock shooters(28 front 31 rear) BIG bog. That was not me sleeping on the RT, lots of tire spin off the line. 2.68 60ft

    2nd pass, changed rear shooter to #33, still some bog but not as bad, 18lbs in tires, 2.09 60ft., still some spin, forgot to turn on electric booster pump, started leaning out on top end.

    3rd pass, 1st round elim. changed front shooter to #31, less bog, 16lbs in tires, 2.05 60ft., slight spin, 12.2 AFR @ WOT, turn same ET as 2nd pass.
    Now is when things start to get weird, I'm shifting 1-2 @ 6000rpm but then hitting 6000rpm in 2nd before the lights! This is a 1/8 track, last combo I was shifting into 3rd just before the lights on a 1/4 track. Got the feeling something was slipping or spinning. Actually shifted into 3rd at the 1/8mi. lights. But I won.

    4th pass got the bye run, changed rear shooter to #35 and took care of the bog, dropped tire pressure down to 14 and for the first time broke the 2.00 sec. 60ft time!
    I had been shifting off the shift light until this pass and watched the tach instead, it seemed to jump instantly from 3500-6000rpm with the slipping/spinning feel, backed off a little when this happened, hit 2nd and then went back to WOT and still set the shift light off.

    Ego wants to think that the tires are breaking loose. But my mind jumps to conclusions and thinks trans or TC slipping.
    I plan on taking it out on a deserted road where I can check things out better and not be limited to a 1/8 mile.
    Race got rained out after that round and I ended up in the top 4. They split up the money in my class 4 ways so I got back my entry fee and then some.

    The first 2 passes before things got weird it pulled strong all the way to 6000rpm.
    The SP3 wants a big shot of fuel going from idle to WOT. rowell3.JPG roswell2.JPG
     
    Gold GS, PGSS, alec296 and 3 others like this.
  2. Max Damage

    Max Damage I'm working on it!

    Thanks for sharing! What is the Transmission you are using?
     
  3. partsrparts

    partsrparts Silver Level contributor

    TH400 3:23 gears
     
  4. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    Any ets with the old heads? Sounds like your getting it sorted out
     
  5. partsrparts

    partsrparts Silver Level contributor

    1/4 et's were low 14's. I have alot of tuning to do to really sort out this combo.
     
  6. Fox's Den

    Fox's Den 355Xrs

    Based on your et and mph in the 1/8 you should be able to click off a 13.60-80 in the 1/4 if you can keep from spinning tires in 60 ft. I would put in a 200r4 trans and a 373-410 gear and it will be a rocket.
     
  7. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    How tall are the rear tires?
     
  8. gsjohnny1

    gsjohnny1 Well-Known Member

    part of the problem is not enough gear. 3.23 are for funeral cars.
    how big is the holley. i used a 650 with no problems, even on the blower.
    i said in the beginning about the s/p the rpm will jump right up there. shifting at 6k, how long did it take to get back to 6k?
    when i used my s/p, rpm jumped to 6500. shift, rpm dropped about 500 and right back to 6500. first time it was ''what the hell happened''
     
    Dano likes this.
  9. Dano

    Dano Platinum Level Contributor

    I'd say 4.33 or even 4.56 w/the 200-4R. Would still give a nice cruising gear with the OD and should launch better. Would have to look @ anticipated trap rpm.
     
  10. alec296

    alec296 i need another buick

    Short shift first by 200-300 rpm. See if you pick up anything. What converter do you have?
    A 2.75 first gear set would help launch.
     
  11. partsrparts

    partsrparts Silver Level contributor

    26" 255/60/15

    Seeing how this was the first time out with this combo I have alot of things to watch and only 4 passes to do it in. First 3 passes were just getting off the line with no bog or tire spin. Now that those 2 issues are taken care of for now I can start keeping a closer eye on shift points and rpm drop.

    JW 3200 stall that actually flashes to 3400

    Keeping the TH400 and will be going to 3:73's. I don't live anywhere near an interstate hwy anymore.
     
    Dano and Max Damage like this.
  12. Mark Demko

    Mark Demko Well-Known Member

    :cool: Awesome!
    Is this in your car in your Avatar?
    Keep tuning:D
     
  13. partsrparts

    partsrparts Silver Level contributor

    Yes. I need a more updated photo.
     
  14. alec296

    alec296 i need another buick

  15. knucklebusted

    knucklebusted Well-Known Member

    alec296 and Max Damage like this.
  16. partsrparts

    partsrparts Silver Level contributor

    I just installed Caltracs on the car a week before taking it to the track, they probably need more preload. I didn't want to try and do to many things at once. It took 3 passes to cure the hesitation and 4 to stop the spinning off the line. I only got 4 passes. next thing is more preload, 90-10 front shocks and disconnect the sway bar to try and keep the rear tires planted.
     
    alec296 and sean Buick 76 like this.
  17. sean Buick 76

    sean Buick 76 Buick Nut

    Do you know how much it weighs?
     
  18. Fox's Den

    Fox's Den 355Xrs

    I wouldn't put special shocks on or disconnect the sway bar or any of that. This is not the way you drive it on the street so why go to all that trouble at the track. Unless you are trying to get a low time but it is not worth going to all that trouble unless you are going to race the car all the time then that is different.

    The suspension on my car is totally different than stock I have large 1 1/2"sway bars poly bushings all the way around.
    The springs are really stiff and I have 77 Camaro spindles up front for the disc brakes. Totally made to handle in the corners.
    I couldn't bounce the car without the shocks the springs were so stiff.

    All of this slows me down in the 1/4 and I am sure if it wasn't for this handling package I would have hit a 12.90 a long time ago on the motor.

    I would keep working on the short time and get that worked out first then work on the top end Work those shooters and cams on the carb to get it all dialed in.
    Then you can play with the timing and the jets for top end power.

    you probably need some kind of traction bars or no hop bars depending on your suspension to keep tires from spinning, It is not a good idea to go to 14 lbs as some of us have done that and you could get squirrley at top end don't forget you are doing 100 mph at this point in the 1/4. n18 lbs in the tires is a better place.

    I am sure car weighs 3200 tops.

    professor out.
     
  19. Mark Demko

    Mark Demko Well-Known Member

    18 seems to be a magic number for me in my MT DR's, I tried 20 it spins a bit, never went lower than 18 lbs
     
  20. partsrparts

    partsrparts Silver Level contributor

    I'm retired so time to switch things back and forth isn't an issue. Yes I am shooting for the fastest time possible. With the last combo I ran the fastest time with the sway bar disconnected and open headers, but at this track open headers will put you in the Pro class.
    It seems the tires are breaking loose at the top of 1st gear and into 2nd so that needs to be cured before I can mess anymore with timing and jets.
    I don't like the 14lbs either so I need to work on the Caltrac pre-load.
     

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