Dyno test tomorrow - what will it make?

Discussion in 'Street/strip 400/430/455' started by 87GN_70GS, Nov 19, 2020.

  1. 436'd Skylark

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

    I'm sure you read my thread this fall when I swapped intakes. the B4B was much more enjoyable to drive over the SP1 around town. No discernible difference when mashing the pedal either- violent wheel spin. I picked up 1-2 mpg too. No track times yet, but I don't expect a huge difference. Either way the improved street manners may be worth the tenth..
    87GN_70GS likes this.
  2. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Yeah, I think I might have to try it. My car is way more of a streetcar.
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  3. 71stagegs

    71stagegs bpg member #1417

    Wizard how do u think the AED 1000 will like dual plane
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    BQUICK Well-Known Member

    Also if a B4B or Performers is massaged there is something to gain. Port equalizing and matching. I picked up over a tenth over stock B4B after Greg Tomilson worked my B4B. Ran smoother as well. There was an article in GSXTRA showing his porting numbers on various intakes.
    87GN_70GS likes this.
  5. Jim Weise

    Jim Weise 1000+HP

    I run the big Holleys on B4B and Performers all the time.. they work fine, typically best with a 1" spacer.. had very good luck with the transition spacer from HVH.. And yes Bruce, I too do the porting and equalizing on the dual planes, one of these days I will quantify that work with a back to back dyno test, with a stock one, and one that is ported. I know already from testing that the port match is worth 15 HP on a 500 HP engine. Been there, done that. We started out with a out of the box performer, did a few pulls, than replaced that intake with a SP-1, and while we were playing with that, Brian at the dyno shop took the Performer into the porting room, and port matched it.. nothing more..

    We then put it back on at the end of the day, and I was quite surprised in the performance difference. This was long ago, all that info is on the hard drive of my last computer, I will have to get those sheets for you..

    I always wanted to duplicate that test in a car.

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  6. 87GN_70GS

    87GN_70GS Well-Known Member

    Best hp with qjet and open spacer 583.
    Best torque with qjet was 600 and semi-divided spacer. It did not like the center divider being removed from the intake, nor did it liked stacked open and divided spacers.
    Last edited: Nov 21, 2020
    techg8 likes this.
  7. 87GN_70GS

    87GN_70GS Well-Known Member

    The dyno shop has both an 850 ultra hp and 950 ultra hp. Which should I ask to try?

    Still have the Thermoquad to run tomoro, was below 10 AFR today.With the qjet pulling 2" of vacuum, its strangling the motor
  8. Bens99gtp

    Bens99gtp Well-Known Member

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  9. Jim Weise

    Jim Weise 1000+HP

    The 950 Scott.. excellent numbers, keep tuning..

    That massive mid range torque is going to feel great in the car.. see if you can get him to start a pull at 3200, so we can see the whole torque curve..

    Last edited: Nov 21, 2020
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  10. hugger

    hugger Well-Known Member

    I said 585 ...what do I win
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  11. 87GN_70GS

    87GN_70GS Well-Known Member

    Send me your address and I'll mail you a box of chocolate Krispy Kremes:D
  12. 87GN_70GS

    87GN_70GS Well-Known Member

    Will do.

    Have you noticed what I saw today, that advancing the timing reduced torque down low but increased hp up top?
  13. BQUICK

    BQUICK Well-Known Member

    Yeah, that's opposite what I thought I knew......
  14. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    At the track, everytime I advance my timing, the trap speed goes up. My best trap speeds are with 38-39* of timing.
  15. BQUICK

    BQUICK Well-Known Member

    I run 4 deg of retard at 5000 rpm (34 back to 30). Always seemed to help MPH.
    That's what the Stinger S4 was all about.....38deg back to 33deg....hot ticket back in the day.
    BUT that was with IRON heads....I'm thinking aluminum heads like a lot more timing than I'm used to feeding iron heads.
  16. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    I tried that as well. I set my MSD digital 6 up with a single stage of retard. I can set RPM and amount of retard. I tried 1-4* @ 5000RPM, and I lost trap speed each time.
  17. Jim Weise

    Jim Weise 1000+HP

    That is an interesting phenomenon Larry... and I do not doubt you, but I can assure you, 39 degrees of timing is killing the motor, most likely to the tune of 20-30 HP...

    So we are left with only two, maybe three possibilities..

    ............your timing light is lying to you.

    .......... Something is happening during the run, that is retarding the timing from where your setting it at in the pits.

    .......... Your heavy car, with a combo that is most decidedly not drag strip optimized, likes the higher timing setting and boost in torque at low speeds..

    With regards to the last possibility

    Does the higher timing setting help the 60'?

    Does the 1/8 mph to 1/4 mph show that the car is pulling harder in that segment?

    Or is the higher mph gained before the 1/8th?

  18. Jim Weise

    Jim Weise 1000+HP

    Maybe... depends on how much we are talking about here. If your talking about torque way down low, below 3500, then that is actually pretty normal.. You give up low speed torque to optimize spark timing for high rpm hp.

    The indicator that you have achieved optimal timing is when it just trims the torque number at the peak slightly and boosts the peak hp slightly.. if we are talking about more than just a couple numbers, in that scenario, then no, I have not seen that..

    Try this for me if you get a chance... once you reach your best pull, simply pull the distributor cap and rotor, and put in the heaviest springs available on the advance mechanism. Be great if they had a set of the monster ones that the MSD distributors come with.

    then do a pull and see what happens.

    87GN_70GS likes this.
  19. standup 69

    standup 69 standup69

    Something I noticed years ago I chassis dynoed my car and found best power with 31 degrees of timing .next time to the track the car felt slow so I put the timing back to 34 deg. The car went faster ...
  20. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Wish I could remember Jim, it has been awhile. I will have to see if I can dig out the time slips and see if I wrote it down.

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