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Author Topic:   Gear for a 1/4 track
Hoosier0707
Dirt Roller

Total posts: 16
posted August 26, 2003 08:29 PM  
I have a performance 406 and a 2speed powerglide trany what gear should i run?

wizzard
Dirt Freak

Total posts: 306
posted August 26, 2003 08:49 PM  
we need more info like rpm you want to run and witch powerglide ya got is it a 1.82?

racer17j
Dirt Forum Champ
Total posts: 5390
posted August 26, 2003 10:07 PM  
Well see im kinda new at this hole racing thing so all I know is that im running 26.5 tires all the way around. Im not forsure what my trany# is all I now that it is a TCI racing trany. And I want to run between 5500-6000 rpms.

b4racing
Dirt Forum Champ
Total posts: 626
posted August 27, 2003 01:49 AM  
take and measure the roll out of the tire rather than what is marked as there can be come big differences. Bobby

gould
Dirt Forum Champ
Total posts: 730
posted August 27, 2003 05:16 PM  
run a 6.50 or 6.66 gear. run the glide in drive.

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Drive it in deep, and come out hard!!

racer17j
Dirt Forum Champ
Total posts: 5390
posted August 27, 2003 06:19 PM  
what is tire roll out. is that tire stagger?

ruggs66
Dirt Maniac

Total posts: 193
posted August 28, 2003 10:09 AM  
Take a tape measure & stick it on the tire tread & roll it across the floor & see what you get.

Probably get a number close to 85 or 86 but that is just a guess.

& Yes that is how you would measure them for stagger

Hoosier0707
Dirt Roller

Total posts: 16
posted August 28, 2003 10:18 PM  
thx they are all 86

ruggs66
Dirt Maniac

Total posts: 193
posted August 29, 2003 01:22 AM  
Ok, now what rearend is in your car?

that way someone will be able to get you close on the gear ratio you need.... they are wanting to know if you will need to run it in 1st gear or drive.

you will need to multiply your tranny ratio by your rear gear ratio to come up with your final gear.


Hoosier0707
Dirt Roller

Total posts: 16
posted September 02, 2003 06:41 PM  
it is a stock gm raer end its not a possy

Eljojo
Dirt Forum Champ
Total posts: 968
posted September 02, 2003 07:19 PM  
You'll need to put a spool in the differential. With out locking the axles together you will be spinning one tire all the way around the track. If your GM rear is a ten bolt you may have to run in low with the "glide and multiply your final drive with the rear end ratio. If you have a twelve bolt, you may install a final drive ratio of 613 and run the glide in high. a 613 may be about right on a 4/10s mi trackwith the tires you are running. (maybe a 3/8-depending on you cam choice)

racer17j
Dirt Forum Champ
Total posts: 5390
posted September 02, 2003 09:17 PM  
I am guessing that he is running a sbc 350. Why would you wnat to run at that rpm when on all of the dyno's I have seen show a 350 torque curve with peak torque in the 4000 to 4500 range drops off quite a bit after that. It seems that there would be alot of tire apin and low torque at that rpm. Yes, I am rookie!!

sideways
Dirt Forum Champ
Total posts: 715
posted September 03, 2003 09:07 PM  
He says he is running a 406.So the rpm will be a bit lower than a 350 for best tourqe curve.But what that is depends on engine package.How ever he is getting good advice on the tire roll out and gear selection.

Hoosier0707
Dirt Roller

Total posts: 16
posted September 03, 2003 10:06 PM  
So i just keep the stock 3.73 gear in my car and that wiil put it to a 6.66 and i will run the glide in high. so is this all i need to know?

wizzard
Dirt Freak

Total posts: 306
posted September 03, 2003 11:00 PM  
with the 3.73's run it in low to get the final you want

racer17j
Dirt Forum Champ
Total posts: 5390
posted September 04, 2003 12:22 AM  
thx guys for the help. if i could run a ford 9inch i would belive me. now will a powertracks unit fit in to a stock rear end. becuz i got 1 from summit racing eqp and that will make it a possy right

racer17j
Dirt Forum Champ
Total posts: 5390
posted September 04, 2003 07:05 PM  
now if i weld the spider gears together wont that break a axel when i turn a corner or spinn out (not saying that i will spinn out lol)

racer17j
Dirt Forum Champ
Total posts: 5390
posted September 05, 2003 04:34 PM  
If you're running a stock metric rearend buy yourself a moser axle for the right side and save yourself rollover!

dirtrace54
Dirt Maniac

Total posts: 192
posted September 10, 2003 03:35 PM  
Questioning the that difference in tracks are slight, the 1/4 mile i ran on with similiar tires, a 3.90 or 3.92 gear put me right around 6400. I was running a 358 instead of a 406, but it had ba**s. I used the 3.73 for the smaller 3/8 around here.

racer17j
Dirt Forum Champ
Total posts: 5390
posted September 10, 2003 04:25 PM  
if your going to weld the spiders use a good ol stick welder and some high nickel rod. its best to take the rearend out and weld it in the flat position. im a welder by trade so just trust me on this one.

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Drive it in deep, and come out hard!!

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