Bracket Talk
Lets talk about tire shake
December 01, 2022, 03:41 PM
imakehpLets talk about tire shake
I'm also thinking of putting the wheelie bar on the car and take the 45lbs off the nose. Don't now if it would help/hurt the shake but it's 45lbs off the car so I could/should pick up some ET
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Dave
F J B
December 01, 2022, 03:41 PM
Mike RietowCould be a 20608. A racer I know won a IHRA Hot Rod Championship with a 540 BBC in Bertozzi's white 68 Camaro, with a 20608 converter.
Returned to defend it the following year and broke the sprag at two consecutive races, might of been three consecutive races. Cost him defending the championship, by the time he made the 20608 converter spragless.
December 01, 2022, 03:48 PM
imakehpI went back out to the trailer and re-checked the box and you guys are absolutely correct, it is a 20608 B&M convertor.
Sorry for the confusion. Even though it was only me confused....lol
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Dave
F J B
December 01, 2022, 03:50 PM
Mike RietowIt could be a lot of different possibilities causing it, with a car that hasn't been run in a while. But if I'm shaking the tires, I'm letting air out.
December 01, 2022, 03:59 PM
imakehpOne thing I noticed Mike is the higher I went up with air pressure the more MPH I lost. If my computer is to be believed I'm going across the 1/8 mile finish line at 7400 ?!? Either the B%M convertor is slipping like a b!tch and/or the tires have ZERO growth.......
I realize I changed WAYYYY to many things at one time and now I have no idea what went wrong.
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Dave
F J B
December 01, 2022, 04:02 PM
B KINGSonoma has bracket racing mid Jan. & Vegas usually starts late Jan. both are 2-day races.
1980 Camaro
Taking the Best Working Small Tire Shyt Box & making it Greater Than Before!
3000 lbs.
Pump Gas 436
December 01, 2022, 04:36 PM
imakehpquote:
Originally posted by B KING:
Sonoma has bracket racing mid Jan. & Vegas usually starts late Jan. both are 2-day races.
Either or both would be fine with me Bryan...I haven't been to Sonoma for at least 10yrs. So it would be nice to see it again.....If I remember correctly there was a couple very good steak houses up there.
If you go also I owe you guys dinner.....
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Dave
F J B
December 01, 2022, 05:20 PM
B KINGquote:
Originally posted by imakehp:
The next time there's a race/TnT somewhere out west I'm going to take my old pair of slicks and try them just to see if the new tires and/or rims are the issue.....
That's a good place to start!
2BKing
1980 Camaro
Taking the Best Working Small Tire Shyt Box & making it Greater Than Before!
3000 lbs.
Pump Gas 436
December 01, 2022, 06:16 PM
Lenny5160quote:
Originally posted by TOP38:
quote:
Originally posted by imakehp:
OK, this is the entire story......
Had #18600 33.0/16.5-15 CO7 4-3/4lbs 13" rims
Went to #18255 14.0/32.0L-15 CO7 4-1/2 to 5-1/2 14" beadloc rims
Had a HUGHES #168997 GM-95 +1/4 7SC+1
Installed a B&M 20908
Launch 4300 to 4800 rpm....didn't go lower than 4300 but shake got better the lower I went
4.10 gear 1.76 1st gear
45lbs on the nose....1950lbs w/driver...
4:80 / 145 in Vegas (2500' ?)
582" 985hp
I'll flash the RPM when the rain stops here in the next couple days....
The RPM is about 400-500 higher between the two different tires and/or convertors (6900 to 7400)
That's about all the info I can think of....ask me if you need more
The Hughes converter is way too tight and agressive. I assume you have a typo error on the B&M (20608 vs 20908). The 608 converter should work very good and it is not aggressive. Ran one of these behind a 565 dragster running 4.50's and 60's at 1925 lbs. Used the 16" Hoosier C06 33.5 tire. No issues either other than some shake in the burnout if you were not careful. Do you need weight in the nose of this car? Especially with the B&M? What ither differences did the converter swap make? I haven't ran a 15" for a long time but I know a number of racers like the MT3084 tire.
In the long run you will be better off running a 16" tire with or w/o bead locks.
That is interesting to read about the 20608. I always found it to be aggressive down low but not MPH very well.
Tony Leonard
December 01, 2022, 07:48 PM
undacuva67I ran a Spitzer hardtail for years sub 4.70,s with 16 beadlocks and various tires , gears and converters and ran 4.5 to 4.75 air pressure pretty much across the board. 30 lbs in the nose to keep the front tires rolling thru the beams instead of wheel stands.
December 01, 2022, 11:01 PM
seabasshughes 7sc, wow that seems tight and aggressive to me from what I remember for your combo
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
Rolla Competition Engines
ProCharger
Hoosier Tires
Abruzzi
December 02, 2022, 12:12 AM
imakehpJ.R. , even with shaking my teeth out the 20608 had a much better 60' time.....the Hughes convertor always worked fine for Pro-lite racing but I always thought the car should 60' better and be faster with better 60'......I've got it in my head that if I switch back to my old rims&tires the shake will be gone......I brought my old convertor, manifold, ect to Vegas with me....everything except my old tires....damn it
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Dave
F J B