I can't seem to get anything better than a 1.62 60ft. Most of the time I cut high 1.6 60fts. However, I'm not spinning my tires, I usually skim the front tires a couple of feet on launch and in this video I get them a couple of inches off the ground

http://media.putfile.com/1160--11695mph

That run was made with my rear QA1s set at 5 and the fronts at 2. I figured with a little over 400rwhp, 4500 vigilante converter, 4.10s and 26" ET Streets I should get solid 1.5 60fts and an occasional high 1.4 60ft. I have more than enough in suspension mods: QA1s, Moroso drag springs, K-member, A-arms Torque arm, rear drag race sway bar, LCAs and PHB.

So far I plan on switching from stock wheels, 4.10s and ET streets to 4.56 gears, 15x4 and 15x10 rims with ET Street radials. I don't think I'll have a problem hooking up with those tires but I'm not sure what change it will make to my 60fts.
I was also considering changing my stall, possibly bringing it down to around 4000, any thoughts on that. I know conventional wisdom is to go up in stall but I've seen several cars on here getting better 60fts in 355s with 4000 stall converters.

 

Your sig says full weight. How many pounds is that?

 

The last time I weighted it, several years ago it was 3410lbs without me in it. Since then I've taken out my bumper supports, A/C, ABS, back seat and spare tire. I've installed a PA K-member and A-arms. However since then I've also switched from a T56 to a 4L60E, 12-bolt rear end, steel driveshaft, torque arm and boxed subframe connectors. In all I think I'm back to my original weight and I'm 200lbs so I figure my race weight is roughly 3600 lbs.

Regardless, a buddy of mine races a 4200lbs LT1 Caprice making around 370rwhp with a 4200 converter and he gets high 1.5 60fts on the same track and same day. His best is a 1.41 and he's backed it up with several high 1.4 60fts

 

You don't need to go any lower than 4.10's with that 4l60e b/c it has a low first gear and you are running 26" tires. I will tell you it took a 4500+converter for my car to get into the 1.4's on motor and does 1.5's with the 4k precision in it.

 

ever think of putting in a th350 or 400 and a transbrake?
Once you go with a t-brake you will never go back and that is for sure

 

I had though about it at one time but I drive my car too much on the street.

 

I also think that it's a TC matchup problem. My set up is 4l60e, 4000 Yank, 4.10s in a spooled 12 bolt, on 275-60x15 Hooiser drag radials. My 60s are 1.45-1.53 depending upon the weather.

Grease are you positive that you're not spinning some? Have you marked the tires and videotaped the launch? The reason that I say this is that ET street bias plys do not squeel when the spin just a little and will hook up after spinning a few feet.

 

I'll mark the tires when I go back to the track next week and get someone to watch my launch just incase I am spinning. I went over some of my run logs and my 4500 converter actually only flashes to around 4000 rpm. I just bought a nitrous kit so now thats going to change my whole tire size/gear and converter combination out of whack. I still plan on getting low 11s out of this car before spraying and inorder to do that I need to lower my 60fts

 

Maybe your tires are old? Or I'd try restalling the converter.

 

What brand converter do you have, some brands work much better that others? Also, have you tried allowing it to "flash-up" at the line, rather than just stalling it up.

With my Vigilante less stall is more on the launch. The only way it works correctly is to flash it from around 1250 RPM and I'm currently getting 1.48 60fts and lifting the front wheels.

WD

 

I'm no expert, but I would try the lightweight wheels and the MT street radials first. I have some nice parts in my suspension, but less than you do. Plus I'm on Eibach pros and stock shocks. The car 60s in the 1.61 to 1.65 range. This is flashing the converter from a 900rpm idle speed. The last converter (Vig. 2800) liked to be flashed too. I would leave the gears alone as mentioned, but if your going to spray, it does look like you might need less converter. Like I said, I'm no expert, just my thoughts on the matter.

 

My car 60-foots in the 1.62 to 1.64 range, my sig tells the basic specs of the car, my convertor is a 10" B&M that came over on the Mayflower it "foot stalls" at about 2200 rpms and it flashes around 2800 rpms. My car only makes 300hp and 300 ft lbs of torque. Weight transfer is the key and getting the suspension to squashe the rear tires in the ground. Some 28" tires and the lighter weight wheels will go a long way.

Check your pinion angle, get your car dyno tested and then send the results to a convertor builder and they will build it for you versus an "out of the box" piece. I used to crewchief for a stock/superstock team and that is where huge gains can happen by having the right convertor.

my humble opinion

 

The converter is a vigilante and I had it stalled with the new engine for the power I'm making and vehicle weight. The car 60fts better the higher up I can bring it rather than leaving at idle. I'm getting light weight wheels this winter and a pair of 26" and 28" MT drag radials for all motor and nitrous days. I've recieved a lot of ideas from this thread so thanks everyone for your input.

Waswa

 

And both of my Yanks have been just the opposite. The higher that I stall it up the quicker it leaves and the better the 60'.

 

Really? I guess I'll have to try it again. I though mine prefered to be flashed.