Re: Could a gear change induce wheel spin at launch?
[Re: J_BODY]
#3021690
03/07/22 10:12 PM
03/07/22 10:12 PM
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Joined: Aug 2003
Posts: 4,670 On the parachute mount
n20mstr
master
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master
Joined: Aug 2003
Posts: 4,670
On the parachute mount
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It depends ? IF the car has enough power , less gear will calm launches down , but 60 the same or sometimes better ….. maybe your power/converter works better with more gear ? It’s hard to say for sure , do you any data logging ? An rpm trace would show a lot here
....BAD A$$ STREET CAR.....
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Re: Could a gear change induce wheel spin at launch?
[Re: n20mstr]
#3021721
03/07/22 11:12 PM
03/07/22 11:12 PM
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Joined: Mar 2003
Posts: 6,334 Heaven
EvilB1Dart
master
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master
Joined: Mar 2003
Posts: 6,334
Heaven
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The 4.30 has more wheel speed and the converter will be looser which could further cause traction problems early in the runs. Same tire and same or similar condition?
"Any fool can know. The point is to understand"
- A. Einstein
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Re: Could a gear change induce wheel spin at launch?
[Re: EvilB1Dart]
#3021733
03/07/22 11:51 PM
03/07/22 11:51 PM
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Joined: Dec 2005
Posts: 11,497 Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,497
Fulton County, PA
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You can absolutely spin the tire from not enough SLR if you are not planting the tire.
That said, I find it hard to be convinced that a small step like that gear change is could make a car go from good to junk. Assuming a 3 speed, that's around a half point of gear ratio. Go back to the old set up and see.
I can tell you that running on a track that is prepped for fuel cars, along with the clutch dust and oil they leave behind, is not typically going to be the best situation for 9 and 10 second door cars.
If the results don't match the theory, change the theory.
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Re: Could a gear change induce wheel spin at launch?
[Re: CMcAllister]
#3021787
03/08/22 07:37 AM
03/08/22 07:37 AM
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Joined: Jan 2003
Posts: 8,018 Tulsa OK
Bad340fish
master
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master
Joined: Jan 2003
Posts: 8,018
Tulsa OK
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I think with a taller gear once you lose the tire it might be harder to get it back, but you didn't make that drastic of a change. It will be interesting to see how it does when you go back.
68 Barracuda Formula S 340
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Re: Could a gear change induce wheel spin at launch?
[Re: dvw]
#3021820
03/08/22 10:02 AM
03/08/22 10:02 AM
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Joined: Feb 2005
Posts: 20,147 PA.
pittsburghracer
"Little"John
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"Little"John
Joined: Feb 2005
Posts: 20,147
PA.
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We race in a lot colder temperatures than that around here but my quickest 60 foot was 1.21 in my Daytona and 1.25 in my Duster. I also have a lot more tire than you do. Even at that when the temps did drop I had to do a longer burn out.
1970 Duster Edelbrock headed 408 5.984@112.52 422 Indy headed small block 5.982@112.56 mph 9.42@138.27
Livin and lovin life one day at a time
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Re: Could a gear change induce wheel spin at launch?
[Re: pittsburghracer]
#3021918
03/08/22 02:04 PM
03/08/22 02:04 PM
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Joined: Jan 2003
Posts: 19,355 Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,355
Las Vegas
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I know a guy that's free in a couple weeks that could help at the Vegas race How old are your tires? Did you change the shocks at all to compensate? Do you have any good video of the runs? Can you email the run files?
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Could a gear change induce wheel spin at launch?
[Re: Al_Alguire]
#3021942
03/08/22 03:00 PM
03/08/22 03:00 PM
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Joined: Oct 2004
Posts: 2,812 Connecticut
FurryStump
master
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master
Joined: Oct 2004
Posts: 2,812
Connecticut
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Did you heat the tire just a hair more to overcome the cooler temps? Could have made them a bit greasy.
Last edited by FurryStump; 03/08/22 03:02 PM.
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Re: Could a gear change induce wheel spin at launch?
[Re: J_BODY]
#3022070
03/08/22 08:28 PM
03/08/22 08:28 PM
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Joined: Aug 2003
Posts: 43,097 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,097
Bend,OR USA
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Do you know the difference in the density altitudes for both tracks? Did you change the jets to run Famosa ? I'm wondering if it picked up enough power due to the altitude and better air out there in the groves to make it spin the tires: work:
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Could a gear change induce wheel spin at launch?
[Re: Dduster]
#3022529
03/10/22 12:44 AM
03/10/22 12:44 AM
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Joined: May 2003
Posts: 13,185 aZLiViN
J_BODY
OP
I Live Here
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OP
I Live Here
Joined: May 2003
Posts: 13,185
aZLiViN
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Slicks have 22 passes. 14psi as always Prior to this weekend I hit that test day in Vegas back in December. Was very cold that day and we loosened the front 4 clicks extension, left the rears alone. I put the turns back into the shocks prior to the 1st pass and took 2 out for pass 2. Burnouts…. yeah probably over did that perhaps…. It was “cold” Ignition….. old school 6AL timing locked at 32. Been that way forever. We went up 4 jet sizes since Vegas was the last run. Was 12.4 afr so we let it be. Starting to wish I’d stayed with my 4150 carb and 727 trans…. Fun consistent combo that definitely ran the number. I’m sure the softer barometer in Vegas might work my way.
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Re: Could a gear change induce wheel spin at launch?
[Re: J_BODY]
#3022720
03/10/22 07:57 PM
03/10/22 07:57 PM
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Joined: Dec 2009
Posts: 20,622 in a cattle trailer down by th...
Guitar Jones
Paddle faster! I hear banjo music!
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Paddle faster! I hear banjo music!
Joined: Dec 2009
Posts: 20,622
in a cattle trailer down by th...
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I had a nostalgia pro stock racer tell me that if the track was crappy they would add more gear, not less, to reduce the wheel speed. Never tried it myself as I was locked into the one gear ratio I could get in a pro gear.
"Follow me the wise man said, but he walked behind"
'92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion. '74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost coming soon! 2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.
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