4:10 or 4:30 gears for a C-4

[351 82GT]

I'm ready to order gears but I want to find out which set would be better for my setup.

351w(.060) 10:1 compresion
ported & polished heads with 1.94/1.60 valves
Comp Cams 274XE cam
2500 stall converter
shorties and flows
Edlebrock performer intake
625 cfm carb
C-4 tranny

My cams powerband is between 2500-6000 rpms
I "might" be running a 28 inch tall slick.

What rpms are some of you guys turning that have either 4:10 or 4:30 gears
I don't want to "run out of gear" before the traps.
I'm at about 4500rpms now through the traps with 3:73's

 

[bluevenom867]

I have a 351 with the same power span as yours but a higher converter and actually uses 3:73 gears.With the C4 and 26" slick I was runing out of gear.I haven't been to the track yet but I would hit 6000rpm's way to fast and only be doing like 110 or so.The 4:10 is a nice gear but do yourself a favor and get a 3:90 gear if your gonna run 28" slicks.

 

[rd]

Assuming you want it to run down the track, figure out what your max desired rpm is, which is what you will shift at and cross the finish line at, and gear for that rpm in high gear.

I am doing that right now, and a 4.30 gear seems to be about 6000 rpm with 25.5 in tall tires. At a finish line speed of about 105 or so. I don't have the data here right now.

Problem is that the same gear wont work for both the eighth and the quarter...... I am going to 4.56 for the eighth.

Any more and you rev higher than you want, any less, and you are leaving et on the table.

 

[PhLoBuS]

4.10's

 

[N8Miller]

4.10s and the 28" tire should be the best for your setup. the tire will help with the gearing a tad, making it like a 3.90, so you wont run out of gear as soon.

 

[87'GTstang]

Go for the 4.10 gears. It's always cheaper to go to a different size tire to help increase or decrease your overall gearing in the end if it doesn't work out.

 

[351 82GT]

Ok.... 4:10's it is!!

 

[tjm73]

I'd probably do 4.30's, but 4.10's will work well too.

You're stall speed in your converter is too low. You should be in the 3800-4200 range with that cam and engine combo.

 

[351 82GT]

I'd probably do 4.30's, but 4.10's will work well too.

You're stall speed in your converter is too low. You should be in the 3800-4200 range with that cam and engine combo.

Yeah, I know, I screw up big time when I ordered that converter. That's probably why it still doesn't want to idle correct at redlights.
I'm thinking 4:30's would be a little too much for the street. My cam range is between 2500-6000 rpm and I don't want to run out of gear before I reach the traps. That's why I was leaning towards the 4:10's

 

[N8Miller]

Well, being that your set on the 4.10s....which is a good choice..... you should adress the issue of the stall. with those ETs, you will wanna launch your car at around 3500 easy. you should get one that is around a 3500-4000.

as for the gears/stall....dont forget me for the good prices on parts