Need Gear Recommendation

Lonnie Cox · 01-06-2013, 05:35 PM

Quote:

Originally Posted by Greg Reimer 7376

Sounds like you're close, but try short shifting it about 6500 and seeing what happens. I usually don't turn a 327 that high through the gears. 5.38's to 5.13's isn't that different-5-7 % or so. You do need 60 foots in the 1.55-1.58 range, though. What class are you shooting for, and what index?

Greg its is a 350 cid the class is I/SA 12.30 index,

Lonnie Cox · 01-06-2013, 05:40 PM

Quote:

Originally Posted by Lonnie Cox

Greg its is a 350 cid the class is I/SA 12.30 index,

converter is ATI 8inch Treemaster Salesman Charlie Plott
The 2 step was not hooked up, seems to do better when I flashed @ about 2800

Joe Abbazia · 01-06-2013, 05:54 PM

look under the hood not the rear.

Rich Biebel · 01-06-2013, 07:26 PM

Quote:

Originally Posted by Joe Abbazia

look under the hood not the rear.

I agree with Joe...

You have a good converter and the gearing is not that far off..

60 foot time is pretty slow....and RPM at the finishline is low....as is your MPH, and gearing it up is not going to help....

Either your motor is pretty weak or it is not tuned right....

Monte Howard · 01-06-2013, 09:20 PM

Gearing is fine, they are right, you need more HP. Look at you r chassis and make sure everything is moving freely. I found 3 tenths in the chassis on my stocker.

But I think you really need some Hp.

rod butcher · 01-06-2013, 09:30 PM

I don't think you need a gear change. You are down on power and/or have a major tuning issue.

B Parker · 01-06-2013, 10:08 PM

My brother and I know that combo pretty well. My brother is the one responsible for the HP being at 287. And I now run a 74 vette with that same motor combo. As all of us know there are a ton of things that could cause your car to be off that much. I'm sure Charlie has you pretty close with the convertor. Michael Beard is right about the shift point. You can learn a lot from a play back tack. It would be easy just to say you are off HP but it would be nice to get more info on your engine. Any dyno numbers? Or any history on the motor? It sure sounds like you are off hp but you could have 4 or 5 things off a little that are costing you several tenths. The only reason at this point that I would change the gear ratio would be if I thought the ring and pinion was bad or set up wrong. The 538 may be faster in the end but if your 513 are set up right they will get you down the track a lot faster than your going. Make sure there not binding when the rear is warmed up. My Brother ran I/SA for the first couple of years in that combo and had 514 in the rear and went pretty fast with a lot less hp than he ended up with. Good luck

Michael Beard · 01-06-2013, 05:56 PM

Quote:

shifting @ 7k

Is this where the shift light is set, where you're pulling the shifter, or when the transmission actually engages? These are three different times/rpms.

I leave with my hand on the steering wheel, and by the time I react to the shift light, reach the shifter, slap, and the trans hits 2nd, it can be 700 rpm past the shift light rpm setting. High gear is far less of a difference, but that 1-2 shift is critical. I use an Auto Meter Ultimate Playback tach, and offset my shift light(s) accordingly. This should be basic stuff, but I've met some people that have raced for a very long time that had no idea where they were *actually* shifting.

I agree with others that much of the ET you're looking for is in the first 60'.

Lonnie Cox · 01-06-2013, 05:57 PM

Quote:

Originally Posted by Lonnie Cox

converter is ATI 8inch Treemaster Salesman Charlie Plott
The 2 step was not hooked up, seems to do better when I flashed @ about 2800

What about my tire the roll out is 96 inch

Joe Marcinowski · 01-06-2013, 06:25 PM

Try some 92.5 radials.

Quote:

Originally Posted by Lonnie Cox

What about my tire the roll out is 96 inch

01-06-2013, 05:54 PM	#3
Joe Abbazia Junior Member Join Date: Aug 2005 Location: USA Posts: 66 Likes: 0 Liked 19 Times in 4 Posts	Re: Need Gear Recommendation look under the hood not the rear.

01-06-2013, 09:20 PM	#5
Monte Howard Member Join Date: Nov 2002 Location: Potomac,IL Posts: 279 Likes: 1 Liked 71 Times in 23 Posts	Re: Need Gear Recommendation Gearing is fine, they are right, you need more HP. Look at you r chassis and make sure everything is moving freely. I found 3 tenths in the chassis on my stocker. But I think you really need some Hp. __________________ Monte Howard 3209 STK, 3208 SS

01-06-2013, 09:30 PM	#6
rod butcher Member Join Date: Dec 2005 Posts: 252 Likes: 298 Liked 132 Times in 27 Posts	Re: Need Gear Recommendation I don't think you need a gear change. You are down on power and/or have a major tuning issue.

01-06-2013, 10:08 PM	#7
B Parker Senior Member Join Date: Sep 2009 Posts: 849 Likes: 980 Liked 2,336 Times in 464 Posts	Re: Need Gear Recommendation My brother and I know that combo pretty well. My brother is the one responsible for the HP being at 287. And I now run a 74 vette with that same motor combo. As all of us know there are a ton of things that could cause your car to be off that much. I'm sure Charlie has you pretty close with the convertor. Michael Beard is right about the shift point. You can learn a lot from a play back tack. It would be easy just to say you are off HP but it would be nice to get more info on your engine. Any dyno numbers? Or any history on the motor? It sure sounds like you are off hp but you could have 4 or 5 things off a little that are costing you several tenths. The only reason at this point that I would change the gear ratio would be if I thought the ring and pinion was bad or set up wrong. The 538 may be faster in the end but if your 513 are set up right they will get you down the track a lot faster than your going. Make sure there not binding when the rear is warmed up. My Brother ran I/SA for the first couple of years in that combo and had 514 in the rear and went pretty fast with a lot less hp than he ended up with. Good luck Last edited by B Parker; 01-06-2013 at 10:16 PM.