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Author Topic:   Gear for a 1/2 mile track
dean_7585
Dirt Forum Racer

Total posts: 88
posted September 04, 2002 07:00 AM
I run at a 3/8 mile track with 6.20 final gear. I am going to try 1/2 mile. What gear would be best for me?? I run a 355 Flattop motor with 202 double hump heads.

PAPPAW
Dirt Roller

Total posts: 17
posted September 04, 2002 07:21 AM
THIS WILL DEPEND A LOT ON THE SIZE TIRES YOU CAN RUN. I HAVE USED 5.67 GEAR WITH 355, TURNED ABOUT 6500 THIS IS USING TIRES WITH 87" ROLL-OUT.

dode
Dirt Freak

Total posts: 417
posted September 04, 2002 09:57 AM UIN: 13209501
We run 5.29's at our local track and turn about 5200 rpm's with 82" circumference tires.

John

Dunbar
Dirt Maniac

Total posts: 119
posted September 04, 2002 11:00 AM
over here I've ran 255/70/15 tires. I run a 408 and a 342 gear i was only turning 5600 and everyone else was turning about 6300. So I went and got me a powerglide tranny and put it in and ran a 323 and I was turnig 6500. If I was you I'd try 342 I ran the same track last yr with a 389 and I was turning 6800 i was usuing a 342 gear...

dirtracer7
Dirt Maniac

Total posts: 106
posted September 04, 2002 07:31 PM
I run a 5.67 with 27.5 tall tire and turn 6400 rpms on 1/2 mile track.

NYhick
Dirt Forum Racer

Total posts: 82
posted September 05, 2002 07:14 AM
You must figure in your tranny!! You have to match up the rear gear to the gear ratio in your tranny to figure your final drive. I run a saginaw 4speed in 3rd with a 373 rear and turn about 5800 on a half mile. My 3rd gear ratio is 1.54 X 3.73 = 5.57 I use the American racer IMCA tires which are run 81-82 inches.

widebody
Dirt Maniac

Total posts: 197
posted September 05, 2002 09:39 AM
MORE INFO !!!

There is much more to a track than its length. Is it a momentum track or all motor, dry slick or heavy, low banked or high banked.
What size tires are you running??
How are you getting your final gear of 6.20. If you were using a 4 speed in 2nd gear than a simple shift to 3rd might do it. on a powerglide, some gear changes are in order.

dean_7585
Dirt Forum Racer

Total posts: 88
posted September 05, 2002 02:13 PM

I don't know alot about the track, I've never raced on it nor have I raced on a 1/2 mile. I currently use a 6.20 final (4 speed in 4th gear) As far as tires the rears are about 84" around. I wen't to the track and looked at it, it seems to be more like a D shape.Long straight front stretch and big sweeping back stretch..
Does anyone know what gears are in a GM 4 speed, because I have a 3.70 gear that I could put in and possibly get the numbers I'm looking for.

racer17j
Dirt Forum Champ
Total posts: 1565
posted September 05, 2002 04:53 PM UIN: 54865418
look in the tool box and check the tranny stuff if you have a gear around 1.52 like in a t-350 you should be fine with that 3.70. most guys here are running 6.0 with 84 in tires turning 6300 or so

Smitty77
Dirt Roller

Total posts: 9
posted September 05, 2002 05:44 PM
Go to RacersGuide.com there you will find a list of transmission ratios.

dean_7585
Dirt Forum Racer

Total posts: 88
posted September 06, 2002 08:07 PM
Thanks for the info everyone and to Smitty77 for the skinny on the racersguide.com web address, I think that site will help out alot !! Looks like I'm going with a 5.14 final. I talked to a couple people that have ran there before and thats what they ran and had good luck with it

NYhick
Dirt Forum Racer

Total posts: 82
posted September 08, 2002 07:56 PM
This track sounds very similar to the track I am running. Where is the track and what is the name

dean_7585
Dirt Forum Racer

Total posts: 88
posted September 10, 2002 08:25 PM
Ionia Racewaypark in Michigan. It used to be called I-96 Speedway.

d4490
Dirt Maniac

Total posts: 113
posted September 10, 2002 08:53 PM
People I talk to about that track in street stock racing is a 5.14 final gear. See you there for Dealers Choice.

dirtracer7
Dirt Maniac

Total posts: 106
posted September 10, 2002 11:05 PM
Dean I run at Hartford,I always thought about running at Ionia but haven't yet.A lot of people up your way used to come down here when I-96 was closed.If you like the 1/2 mile you should try Hartford.

Arkie Dirt Racer
Dirt Full Roller

Total posts: 69
posted September 11, 2002 12:31 PM
there is a 1/2 mile track not too far from here that we go to sometimes. most everybody there is running 6.33 to 6.50 gears, and turning about 6500-6700 RPM. at our local 3/8 mile track we run 6.50's and turn about 6000 rpm.

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