Bracket Talk
Conv headed ,598 on alky perfomance in a 1950 dragster

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October 05, 2020, 12:10 PM
Mike Frizie
Conv headed ,598 on alky perfomance in a 1950 dragster
Just wondering what performance any of you running a similar combo are seeing peformance wise. I.E. 60ft times, 1/8 et and mph. best im seeing is mid to upper 4.7x's @ 143, 144mph. feel like my 60' foot times and mph are off compared to other combos. I've tried multiple carbs, converters, and rear gear changes. also double checked timing and found it 6 degrees high, moved back to 34. still absolutely no change. thoughts. what am i missing.


Michael Frizie
ET 2471
October 05, 2020, 12:42 PM
SP 124X
I don't have a 598 but I have a 555 with an APD 1250 thats been 4.75 @145 but really hovers around 4.79-4.81 143-144. Mine is in a hardtail that weighs 1930.

The worst air I saw all season was the SFG Million and I was going 4.81-4.85 that week if you happened to be at that race.

I'm no expert but with everything you've changed I'd say you're just not flowing enough cfm to make the HP or it's down on compression.


Denis LeBlanc

October 05, 2020, 12:52 PM
Mike Frizie
should be 15:1 . so says build sheet.


Michael Frizie
ET 2471
October 05, 2020, 01:07 PM
TORQIN
My son Cory's Ezell Dragster has a Wilson steel block 598 with BB3s with 1250 alcohol APD went 4.62 at 148 in Bristol last week with 1.04 60ft and went 4.53 at 150 in Galot the week before...car weighs 1885 with skinny man in it!
October 05, 2020, 01:24 PM
Mike Frizie
assuming scales i used to weigh mine with my fat azz in it i was at 1960 sitting in it. rupert 1250 on mine . i only ran 4.8's at 142 at bristol.


Michael Frizie
ET 2471
October 05, 2020, 01:32 PM
seabass
My dads was running 4.4-4.5 conventional head single ally carb


J.R. Baxter

""Fathom the hypocrisy of a Government that requires every citizen to prove they are insured ..but not everyone must prove they are a citizen."

2025 Miller
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Abruzzi
October 05, 2020, 01:45 PM
TORQIN
quote:
Originally posted by seabass:
My dads was running 4.4-4.5 conventional head single ally carb


Rusty's ran REALLY well all times of the year too !
October 05, 2020, 01:57 PM
Mike Frizie
just cant seem to find where the mis match is at though. nothing ive tried has made any changes.


Michael Frizie
ET 2471
October 05, 2020, 03:04 PM
TOP38
quote:
Originally posted by DRB Motorsports:
Just wondering what performance any of you running a similar combo are seeing peformance wise. I.E. 60ft times, 1/8 et and mph. best im seeing is mid to upper 4.7x's @ 143, 144mph. feel like my 60' foot times and mph are off compared to other combos. I've tried multiple carbs, converters, and rear gear changes. also double checked timing and found it 6 degrees high, moved back to 34. still absolutely no change. thoughts. what am i missing.


What are you expecting? From your numbers your motor is making 925 to 945 HP. You listed no cam, head, intake motor info, no converter trans gear and tire info...

If your heads are on the small side, try a gas carb, you will see a performance gain if so.
October 05, 2020, 03:22 PM
Mike Frizie
intake is bm 2017
heads are bb3 rec ports ( i wanna say 380cc runner) but not the cnc version from brodix
cam is really close to the RM 420-117 numbers
have tried both a 4.10 and 4.30 rear gear, both with 3191 lil
bubba tires. one converter stalling 6800, the other 6600
car has wing and beadlocks.


Michael Frizie
ET 2471
October 05, 2020, 03:45 PM
TOP38
quote:
Originally posted by DRB Motorsports:
intake is bm 2017
heads are bb3 rec ports ( i wanna say 380cc runner) but not the cnc version from brodix
cam is really close to the RM 420-117 numbers
have tried both a 4.10 and 4.30 rear gear, both with 3191 lil
bubba tires. one converter stalling 6800, the other 6600
car has wing and beadlocks.


What for the gear change do?

Is the wing a real one or just a rule wing that does nothing like the old Undercovers?

If you can borrow a good gas carb and you pick up a reasonable amount I'd say your current carb and or heads are holding you back. But I don't think there's a bunch if any missing either.
October 05, 2020, 03:48 PM
Mike Frizie
weird part about all the changes is not a positive or negative change at all .


Michael Frizie
ET 2471
October 05, 2020, 04:05 PM
NC3x58
quote:
Originally posted by DRB Motorsports:
intake is bm 2017
heads are bb3 rec ports ( i wanna say 380cc runner) but not the cnc version from brodix
cam is really close to the RM 420-117 numbers
have tried both a 4.10 and 4.30 rear gear, both with 3191 lil
bubba tires. one converter stalling 6800, the other 6600
car has wing and beadlocks.


The wing can be worth up to .05 et, but if the heads aren't the CNC version of the bb3's, I would have to venture a guess to say that that could be your culprit.. But also, what are the cam specs? Being "close" to the R-M 420-117 can leave a lot of variables in the air with the cam also.. I would try to list the cam if you could, and maybe find out more info on those heads.. But realistically, mid-high 4.70's with a 598 on alky and non-cnc heads at 1960 lbs doesn't sound that far off..


Nick Craig

1971 Camaro Split Bumper
376ci LS3
October 05, 2020, 05:00 PM
00 DEAD ON
I got a 598 in my dragster 1980 lbs on the starting line. Terminator and a PTC 10” Conv. This past Saturday at MDIR I went 4.70 @ 144
Lil Bubbas and 430 gear. Conv falls back to 6350 after the shift. 7300.


Brian Mollison
2013 American Dragster
2020 Sumerduck Dragway VA Top ET Champion
2017 Sumerduck Top ET & SSS Track Champion
2017 MAC Top ET Track Champion
2009 Sumerduck Dragway Va Top ET & IHRA SSS Track Champion
2008 IHRA Division 1 Top ET Bracket Final Runner-up
2007 Colonial Beach Dragway Top ET Track Champion
October 05, 2020, 05:17 PM
Mike Frizie
Wow, 900 fall back


Michael Frizie
ET 2471
October 09, 2020, 10:54 AM
Triple Nickel
If you can get the weight down to 1900 range 4.75 in 2000' should be possible and upper 4.60's when weather and track are really good. My son's 598 is 2000 on the starting line and runs upper 4.70's low 4.80's in 1500' of air. Low 4.80's this summer when it was bad hot out. It made 1025 and 830, but i've been playing with converters all year so i think it has more left in it.