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Author Topic:   Gear
Dirt Roller

Total posts: 9
posted August 08, 2005 08:24 AM  
How many RPM will I pick up by switching gears.

I am running a 5.43 now with a 358CI motor with a MWM #8 cam. I have a 5.83 I can borrow and try if I want. I am running around 5800rpm at the end of the straight now.

I am running on a dry slick 3/8ths mile banked track and getting pulled bad off the corners. I am caught back up by the end of the straightaway then get pulled off the corner again.

Ran my first race a couple weeks ago and the car seems to handle great but just doesn't have the pull off the corner.

Any Help??


Dirt Full Roller

Total posts: 60
posted August 08, 2005 10:16 AM  
The Gear ratio calc in the tool box says...

5.83's will equal 6225rpm.

That should get you a little more pull outa the corner. make shure your valve springs can handel that rpm or it wont do you no good.

If it has wheels or a skirt, you can't afford it! But they shure are fun...

Dirt Freak

Total posts: 255
posted August 08, 2005 11:37 AM  
Not sure how our 3/8's compare, but I run a 6.12 with a 406, and get pulled bad, I'm looking for a gear.

At the two tracks I run, most street stocks are running 6.33 to 6.5.

Dirt Freak

Total posts: 461
posted August 08, 2005 09:24 PM  
That #8 needs to turn 6800 and if you have z28 springs on there (wich you should anyways with that cam being over 500 lift) it can handle it we turn our motors 6700 to 6900 all the time also on that #8 cam adding 1.6 to the intake help out but if i was you i would put a 620 in that thing turn the wick up on it and sail i will bet you anything you will be very happy

But he!! dont listen to what we have to say we have only run almost every cam out there in a hobby stock for 20 yrs we have no idea what we are talking about LOL

Dirt Roller

Total posts: 9
posted August 08, 2005 11:41 PM  
I got 600 lift spings on ported 487X heads.......Got all good stuff in the motor, forged domed pistons, I beam rods, all balanced.

Like I said I am new to this and just ran my first feature Sat. I don't expect to win but getting pulled bad off the corners is discouraging. lol

I will put the 583 in and see what happens this week.

If anyone has a 28 spline 583 the would want to sell I would be interested.

Thanks for the replys

Dirt Maniac

Total posts: 149
posted August 09, 2005 06:12 AM  
As stated before there is the gear calculator in the tool box. I always figure close to 100 rpm's for every .10 in gear will get you fairly close. I wouldn't be scared to turn that thing even higher, like with a 6.00 or 6.20. If all else fails ask around at your track, most guys are more than willing to help out. Well at least until you start beating them. LOL

tin cup
Dirt Full Roller

Total posts: 40
posted August 09, 2005 02:15 PM  
I run a 620 on our 3/8ths. I wouldn't go lower than that.

Dirt Full Roller

Total posts: 38
posted August 10, 2005 11:41 AM  
Our local street stocks run a mild bank 5/16'ths mile track. I have sold everything from a 5.67 to a 7.00 gear for these guys. Gearing IS NOT the same for every car, but if you spend a few minutes asking around what the top 10 cars run you should get a good average (assuming they tell the truth...). Our "average" gear is a 6.50, but the winners win with a 6.86 or so. Most of the Chevy guys multiply through the tranny to get thier final ratio so you get some pretty interesting numbers. Those pesky Furds tend to pull better with a taller (numerically lower) gear because their torque curve is lower in the RPM band then the Chevys. Those that choose to shift on starts and restarts are crazy...
If you have the money, put more gear into it until the motor blows up. Then just go back one step in gear... That should put you where you need to be, HA HA.

The Flash32
Dirt Maniac

Total posts: 120
posted August 10, 2005 04:49 PM  
Tin cup, we run alot lower than that! We are turning right at 7000 every night.

Dirt Maniac

Total posts: 188
posted August 10, 2005 07:55 PM  
Originally posted by The Flash32:
Tin cup, we run alot lower than that! We are turning right at 7000 every night.

What final are you running and on what size track?

The Flash32
Dirt Maniac

Total posts: 120
posted August 10, 2005 09:03 PM  
3/8's semi-banked in OKC...6.83...factory stock class


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