CLOSE RATIO OR WIDE RATIO T 10

Has anyone really compared the differance in the two? I have a close ratio 2.23 first gear and it launches slow but second gear it really takes off. I have a wide ration with a 2.63 first gear and that should launch better on paper anyway .but of course 2,3,4 are wider ratios so on paper the rpms will be harder to keep up high , but for street running the wide one seems like a better choice. I have 3.54 rear end with a built 390 in a 70 AMX.

Before i switch out i thought i would check with the experts.

Before you go changing anything did you have your engine dyno'd? If so where & how much power did it make?

I have a 69' amx 390 (450hp @5800 & 440tq @ 4900)with a 2.23 first gear. It works great on the street, and good at the track. At the track I launch @ 5000-5500rpm and it bogs very slightly. Gaurantee the bog would go away with a 2.43 or a 2.64 first gear.

If you have a 2.64 wide ratio laying around throw it in and try it. Changing a 4-speed should only take maybe 4 hours or so.

I forgot to mention at the track I am using 26x8.5-15 m/t slicks. If you are using regular street tires on the track I would suggest staying with the close ratio as you will have plenty of tire spin.

NO DYNO, it is a 70 390 engine 60 over with ross forged pistons A elgin cam 244 duration 518 lift roller rockers. stock heads with a little work on them , air gap with a 800 edelbrock , headers and msd. since i had another 390 about the same build and it had 296 hp at the rear wheels and 378 torgue so its in that range im sure. running stock 14 " wheels with 235 /70 tires , i will run this at the strip maybe once in my life.

I think with your engine specs & rear gears you'd be fine staying with the 2.23 trans.

I went ahead and did the swap , took about 2 hours with help of a lift and a freind. with the wide it really launchs better and it is easy to drive around town. 2.23 is a long first gear for sure,. But with the close ratio second gear it pulled hard. with the wide it does not but pulls harder in third. ? which is faster i like the 2.64 for the street but to be honest if you miss a gear in any car it does not matter.i am going to run the wide for awhile ,we will see.