#1  
Old 10-30-2024, 09:38 PM
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CraigG. CraigG. is offline
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Default Improving 60's with loosening the Converter?

Could I gain much from increasing stall from 4,500 on "8 race converter and Turbo 400 with a brake to 5,500 or so?

Shift at 6,500 - 6,800

1/8 = 6.61 with a 1.41 at 106
Combination:
72 GTO - Race weight 3400 with me
Elevation 980 Feet
465 and 12 1/2 to 1
455 bored .040 over
Bore … Stroke…
Hand Ported E-heads - '1999 - '2000
Heads Flowed 331 int. and 235 ext.
72 CC milled .060
Zero Decked
Flat Top Ross Pistons

Solid Roller at 276 / 279 at .050 and .635 lift
Installed at 104
Comp Cams - Grind# P8 4028B / 4049B R 108.0
Intake Exhaust
Valve Adjustment .020 .022
Gross Valve Lift .631 .630
Duration @ .020 Tappet Lift 312 316

Valve timing Open Close
@ .050 INT: 30 BTDC 66 ABDC
EXH: 67 BBDC 31 ATDC
108.0 Intake Center Line
Intake Exhaust
Duration @ .050 276 279
Lobe Lift .4210 .4200
Lobe Separation 108

MSD 6AL 2
MSD Billet Dist.
Advance Locked at 34 degrees
North Wind
Holley 1050 Dominator
"3 1/2 x 16 air filter

"2 Hookers Headers
Turbo 400 with a brake
"8 4500 stall on the brake
4.11 gears with MT 10.5w x 28 slicks


Last edited by CraigG.; 10-30-2024 at 10:15 PM.
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  #2  
Old 10-30-2024, 11:04 PM
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Scott Stoneburg Scott Stoneburg is offline
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If it hooks I would say yes.

  #3  
Old 10-31-2024, 05:32 AM
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It sounds like you might have a high enough power band for it rpm wise, but if your hp is nosing over by 6500 it's hard to be sure without having a dyno sheet to confirm what's going on.

What does that 4500 converter you have now flash to?

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  #4  
Old 10-31-2024, 09:35 AM
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I don't know about the flash - if I footbrake it will flash to 4,500. It will set at 5,000 on the brake - I have only gone to 4,500 with the 2-step.

  #5  
Old 10-31-2024, 09:36 AM
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What stall converters are stock and super stock class cars using?

  #6  
Old 10-31-2024, 12:25 PM
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In my combo going from a 4,500 to a 5,000 of the same brand my car actually slowed up a bit .

  #7  
Old 10-31-2024, 09:48 PM
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Yes if converter is built right. We run a 5600rpm stall in GTO and shift it at 6400

  #8  
Old 10-31-2024, 11:10 PM
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slowbird - who do you use and what converter?

  #9  
Old 11-01-2024, 06:14 AM
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U need to know a few things, where does it flash stall to now, where does it drop on the shifts, where’s it go thru the traps at?

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74 Grandville 2Dr 455 c.i 4550#
2011 1.60 60 ft,7.33@94.55-11.502@117.74


2017, 74 firebird -3600 lbs (all bests) 1.33 60 ft, 6.314@108.39 9.950@134.32
M/T 275/60 ET SS Drag Radial

2023,(Pontiac 505) 1.27 60 ft, 5.97@112.86, 9.48@139.31.... 275/60 Radial Pro's
  #10  
Old 11-01-2024, 10:38 AM
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What might be the cheapest way to get that data?

  #11  
Old 11-01-2024, 01:21 PM
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I think you should pick up with more stall. Your combo is really close to the 463 I ran for several years. You have a little more cam and compression. It really liked the 10" PTC I have. It would stall to 5000 but lock up really well at 6500 through the traps. Typical 60' was 1.41-1.43 running low 10's @ 132-133. The way I measure stall is to go WOT at abut 25 mph in high gear.

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Greg Weigart

IAIIA 520/pump gas/SD 325 E-heads/266-272 SR cam/1050 Dominator/3.73/ET Street Radial Pro/3300lbs/1.35 60'/6.21@110.47/9.77@137.08

Hot Rod Drag Week finishing averages:
2014 - 11.12 @ 118.56
2015 - 10.84 @ 124.97
2016 - 10.56 @ 127.88
2017 - 10.29 @ 130.74
2018 - 10.29 @ 130.53
2019 - 10.16 @ 132.34
2021 - 10.09 @ 132.69
2022 - 10.13 @ 133.07

  #12  
Old 11-01-2024, 04:23 PM
Dragncar Dragncar is offline
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Quote:
Originally Posted by CraigG. View Post
What might be the cheapest way to get that data?
Playback tach. 400ish $

  #13  
Old 11-01-2024, 07:25 PM
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Quote:
Originally Posted by Dragncar View Post
Playback tach. 400ish $
A playback tach is a pretty handy tool! This is the playback of my 25mph WOT test with the 10" PTC behind the new 520.

https://youtube.com/shorts/sXlpb65TE...kxzhEn5OTVjOMX

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Greg Weigart

IAIIA 520/pump gas/SD 325 E-heads/266-272 SR cam/1050 Dominator/3.73/ET Street Radial Pro/3300lbs/1.35 60'/6.21@110.47/9.77@137.08

Hot Rod Drag Week finishing averages:
2014 - 11.12 @ 118.56
2015 - 10.84 @ 124.97
2016 - 10.56 @ 127.88
2017 - 10.29 @ 130.74
2018 - 10.29 @ 130.53
2019 - 10.16 @ 132.34
2021 - 10.09 @ 132.69
2022 - 10.13 @ 133.07

  #14  
Old 11-01-2024, 09:42 PM
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AG AG is offline
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Another good tool to have is a GOPRO. I use one in my race car positioned to see the tach, gauges, fuel pressure gauge and the back of the drivers head, it makes evaluating a run really easy. I also have a dual FAST A/F gauge with playback, gets you all the data you need for the budget racer.

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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
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  #15  
Old 11-02-2024, 08:51 AM
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Fetch used GoPro and mount it inside on roll bar etc, I’ve done that for years and I can zoom in on the gauges etc

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Darby
74 Grandville 2Dr 455 c.i 4550#
2011 1.60 60 ft,7.33@94.55-11.502@117.74


2017, 74 firebird -3600 lbs (all bests) 1.33 60 ft, 6.314@108.39 9.950@134.32
M/T 275/60 ET SS Drag Radial

2023,(Pontiac 505) 1.27 60 ft, 5.97@112.86, 9.48@139.31.... 275/60 Radial Pro's
  #16  
Old 11-02-2024, 04:59 PM
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I used my android cell phone on the roll bar with a Big fail as picture, vibration and sound distortions.

GoPro recommendations - model, features, vibration and sound qualities?

Thanks, Guys

  #17  
Old 11-02-2024, 08:20 PM
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AG AG is offline
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My converter stalls at about 5000 rpm but probably should stall at 5500. My typical 60' is 1.45 and i think it would improve with a higher stall. I shift at 6500 rpm and go across the line at 6700 rpm so you would probably improve your ET with a higher stal, which is very tricky to get right without spending a lot of $ through trial and error.

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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
  #18  
Old 11-02-2024, 09:20 PM
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AG what transmission, Brake or rear gear do you have?

  #19  
Old 11-03-2024, 08:42 AM
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My car stalls about 5000 rpm and I 60' between 1.26 to 1.30 on a 9" tire.

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  #20  
Old 11-03-2024, 10:37 AM
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Quote:
Originally Posted by CraigG. View Post
AG what transmission, Brake or rear gear do you have?
I run a TH400 that I built with a full manual reverse pattern valve body, use a 3.90 rear gear, 28" tire and use a Redneck Racing 9.5" converter that has 6.5% slip across the line. I could use a slightly higher stall, 5400-5500, to get a better 60' time.

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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
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