So...most tracks around me are running 1/8 mile. Was thinking of building another 9in center section with more gear. Now it has a 3.50 gear with 28.5 tires. Goes thru traps at 136 at 6200. What gear would be good to go thru at 6200 or a bit less? I expect converter slippage will be less with more gear. Was thinking 4.30 or 4.56 Should improve the 60 foots! 1.38 now. Went 1.31-1.34 with 3.89 gear.
It’s actually a complete center,with 31-spline spool that I am going to separate. Way too steep for me.
I run 4.30's with a 31" tire. I go through at 6100 in the 1/4 (1/4 is what converter is set up for). I go through at 5800 in the 1/8, she really starts locking up the second half.
Assuming you're shifting manually, gear it so it's in high gear asap without running out of RPM at the finish line. Gives you more time to focus on "driving the stripe".
automatic ....let 1-2 shift then i do 2-3 unless I'm trying to slow it down then I leave in "drive". What do you think 1/8 trap rpm will be with 4.30 or 4.56?. Couldn't find a calculator online and Moser no help.
Mine started with a 500 gear and was out of steam at the 1/8. went to a 4.56 and it put me at 6200 in the traps @ 6.60's @ 103- 104 . Dropped down to a 4.11 thinking it would slow me down a bit but be able to stretch her out to run the 1/4 if I wanted but it actually went faster with a 6.38 @ 108 mph going through the traps at 5800. All runs on a 29.5 tire.
So I'm thinking even 4.30 might be too much for me with 28.5 tire. Maybe just leave it alone and be easy on the motor. Sure would like to see the launch with 4.56. Hmmmm....I do have a low gear set for the T400. Maybe throw that in there and leave the rear alone....
I have 4.10 in mine, just last sat we went 6.78 in the 1/8 @ 100mph. Shifting at 6500 from 1st and 2nd I was going through the 1/8 mile at just under 6000. A few days b4 I ran it through the quarter was 6400 at 122mph. My converter needs some tweeking.......going through near 12% slip. My 60ft time were not where they should be either at only 1.485. Car with me in said 3700 when I drive over the scales at norwalk. No spin felt good,even and straight. Tires are 29x10x15 hoosiers I think once I get the converter set up a set of 4.30s or 4.56 will work well for us The 122mph 1320 was on a soft tune wed that went 6.95 in the 660' after some timing it went 6.78. 660'mph was up 2 after the timing change so 1320 mph should be up a few too
Do you have only the 1st gear that is lower,or do you have a different 2nd gear as well. Just from my observation,the people that only changed the 1st gear ended up driving over it in the water box or leaving the tree. 1st gear spins the opposite direction than 2nd gear,and it spins about twice the rpms as the engine. When you shift from 1st to 2nd,it’s spinning,and hasn’t to instantaneously stop and go the other way. Sometimes they go bang,especially when you spread the ratios apart.
It's the whole gearset with different ratio for 2nd as well. I know there will be more drop in rpms between 1-2. That's why I took it out years ago. No et gain. Just a couple on the 60ft. But, that was with 4.10 gears....didn't really need it.....now with 3.50 I think it would help 60ft even more. I do my burnout in drive and let the trans shift thru the gears in the burnout.
