Secs-10

Got my mustang together and took it to the track last weekend for test n tune day. Had all kinds of issues with the tune but it ran a best of 6.97 @111 with a 1.9 60ft and peddling it twice. I couldnt get it to leave the line at all and my best 60ft was a 1.8 and that was leaving right above idle. We never could get it to get up on the converter without spinning the rear tires or trying to push the front. Im running a 3600 stall Revmax converter. On footbrake i couldnt get it to stall past around 2500 before it would spin. So then i started using the e brake as well and even then it would struggle to get close to 3k. Is the problem the low comp(8.5:1) 5.3 not having enough juice to get it up there? Would a trans brake fix this issue? The trans is fixing to get pulled and get rebuilt in the next week. So should i go with a brake or will the weak low comp 5.3 still have the same problem and not stall past 3k. This is a street/strip car prob 60/40. If i go with a loose enough converter for the weak 5.3 to stall will i loose much top end speed? Could a small shot of nitrous off the line be a better answer than going with a brake? Sorry for the ignorance guys. Any help greatly appreciated. Heres some more info on the car if it helps.

3250lbs with me in it
Stock Lm7 5.3 w/317 heads
Th400 3600 stall
Bw s475 t6 turbo
3.08 gear
28" tire
Megasquirt 3x

mrvedit

The way I read it you have traction problems.
IMHO, it only makes sense to go to a higher stall converter (and certainly a transbrake) if you currently have full traction.
If you spinning the tires off the line, you have plenty of juice.

Similar to your car, my '81 Camaro always has traction problems (with drag radials) and both a 2400 and 3600 converter give me exactly the same times.

Solve your traction problem first.

Or am I missing something?

btlfedbu

sounds to me like the converter is too tight to let it build boost, id call a conv company and asked but in my opinion its conv.