Best gear for 2.97 magnum xl

[deathwishracer]

So, I install a magnum xl with 2.97 first gear in my 2010. I have 4.10's, and run a 275/60/15 radial pro. The taller first gear compared to my 5 speed, has killed my 60ft. Also, the lower 3rd gear requires me to now go to 4th, where before II could go through the 1/8th in 3rd. Would a 4.30, or 4.56 rear gear be better to get some of my take off back, and get a little pull in 4th?

 

[rcm90]

How much power? What did it 60' before and after the trans swap? What rpm are you going through in 4th?

 

[deathwishracer]

440hp/480tq on 100 shot with nitrous outlet plate. Best with 5 speed was 1.51 60ft, 7.42@93. After magnum install, tuned a/f on the plate a little. Picked up 2 mph, et was consistent 7.40's@95, 60ft consistent 1.62. The magnum shifts perfect, which helped, but I am sure the extra shift took a tenth, which is right before the light. Shifting at 6500, which the dyno shown is a little past my power range.

 

[deathwishracer]

I know guys with twice my power love the 2.97 first gear with 28 inch tires. But after the load of cash this trans cost, adding power is just not an option. But rear gears are cheap and easy. Just hoping someone had tried the lower rears with the magnum.

 

[05yellowgt]

4.30 gear will probably suit you well. I ran them while na on my 3v and got low 1.7x 60 foot times on drag radials. 4.56 might be a little much with the nitrous if you are spraying out of the hole.

Sent from my Nexus 7 using Tapatalk

 

[05yellowgt]

Oh I just noticed you are on 28" tires so the 4.56 might be good

Sent from my Nexus 7 using Tapatalk

 

[deathwishracer]

That's what I was thinking. And since I'm having to go to 4th now anyway, a little extra pull might help

 

[skwerl]

I loved my T56 in my Bullitt but it sucked ass at the strip. First is too tall and 4th is too short. Horrible gear selection for drag racing but the trans works so damn well. I had 3.73 gears and was contemplating going to 4.10s before I wrecked it.

 

[deathwishracer]

So, made some more passes last night. Best 60ft was 1.59 on a 7.41 run. Very tempted to try the 4.56's. I am leaving with everything she has on the spray. Pro's are hooking, but that tall first gear is killing me.

 

[skwerl]

My best 60' was 1.52 I think, mostly 1.6 range. No matter how hard I launched I would bog right off the line. Frustrating as hell and part of why I don't want to begin the long, expensive journey of attempting to drag race my new car.

 

[deathwishracer]

Went to different track last night with better air. First pass pulled a 1.52 60ft, ran a 7.26..the rest of the night was 1.55 60's with 7.30's and 7.40's....I just feel like if I can get the bog back out of the car, I can 60 in the high 1.4's, and run some lower 7's..The goal is to eventually make a little more power, and have a 6 second 1/8th mile totally street car. No weight taken out, no loud clunking, no interior delete, cruise on Sunday with the wife with the top down, fly at the track!

 

[skwerl]

I think it may have something to do with torque management in the tune, but I'm not sure. I definitely think you can use a better tune than Bama though. Seen too many scary tunes from them to trust them on a race tune.

 

[deathwishracer]

New personal best at a different track. 7.22@96 with a 1.50 60ft. Still trying to decide on the 4.56 gear to get more leave with the tall first gear

 

[skwerl]

New personal best at a different track. 7.22@96 with a 1.50 60ft. Still trying to decide on the 4.56 gear to get more leave with the tall first gear

It's a balancing act with running out of gear in the top of 4th at the stripe. You can play with rear tire diameters as well to get a few mph out of it. What's your trap speed now?

I was running 3.73's so even with 643hp I needed a 26" tire to leave the line. I was running out of gear at the top end at 137mph (I think redline was at 140). If I hadn't totaled it I was going to try 4.10 gears and a 28" tire.

 

[deathwishracer]

I guess I will keep playing with the 4.10's, until I find the stopping point. If I can get into the 7.teen range with a 1.49 60ft, I might leave the 4.10's, and save up the cash for a dynotune, and bump up the shot to 125.