how much boost to leave with

[BOSS 6]

how much boost to leave the line with a pt61

 

[brian]

As much as your brakes will hold!:biggrin:

Every combo is different. If you have a trans brake you could leave very hard.
With my PT-61, I am able to hold, and launch with 6-10 psi on the footbrake.
On my 63, with a 3500 stall, I can only muster 3-5 before pushing through the lights.
Around 5psi, with the right converter you should be good.

 

[jasjamz]

At the track with slicks, start with 2psi and work your way up.

 

[Quick6'n'-K.C.]

See signature for timeslip, also can read about what else is done to my setup in the timeslip data section.

I am able to leave at 13-14 psi of boost with the footbrake on a set of 28x9 et drags that are at least 6 years old.

The reason i have to leave so high is the stock convertor doesnt spool it up too fast off idle, takes 6 seconds to hit 14psi.

BW

 

[Red C5]

It could be different everytime you go out. Just depends how much your tires can hold.

 

[jetmech]

On the t-brake im leaving at 15 at 4700rpm. :biggrin: Im getting moser axles over the winter to be safe.

 

[Quick6'n'-K.C.]

On the t-brake im leaving at 15 at 4700rpm. :biggrin: Im getting moser axles over the winter to be safe.

What were your 60's on those launches with the t-350 tranny?

BW

 

[RatFink]

Same turbo, I tried 10psi tonight and boiled the MT DR for 100 ft. Tried about 7psi and it did a 1.73 60ft and it was pushing, anymore and the brakes would go. Car is running sh*tty though. 12.23, 110mph. I thought it would been way better.

 

[Quick6'n'-K.C.]

Same turbo, I tried 10psi tonight and boiled the MT DR for 100 ft. Tried about 7psi and it did a 1.73 60ft and it was pushing, anymore and the brakes would go. Car is running sh*tty though. 12.23, 110mph. I thought it would been way better.

Your trying the ebrake launch on the TTA right?

What convertor?

BW

 

[BOSS 6]

I was just wondering because im fairly new to the turbo regals but when I come out of tha shop I want to be tha street "KING". I will be running a fresh motor with ported heads, pt61,downpipe, still up in tha air who will build my trans. I already purchased a 2800 stall from PTC front mount intercooler

 

[Quick6'n'-K.C.]

Then get some racegas or at least a methanol chip to get the boost and timing up to make some real numbers.

You can make some good numbers, but it aint gonna come outta da shop runnin 10's :smile:


BW

 

[RatFink]

Your trying the ebrake launch on the TTA right?

What convertor?

BW

No ebrake, just regular foot break launch. 2800 convertor.

 

[Alky V6]

If you use nitrous assist, you can leave the line from an idle. Or, you can WOT on the first amber. For that one though, just make sure your wheelie bars are attached.

 

[D's GN]

Are you guys gradually building the boost up to the desired level on the footbrake and then going WOT on the green? I usually go WOT from the start and let go when the light goes green timing it so boost is at least 6-10lbs. I'm wondering if the stall converter will "flash" a little better the first way?

 

[RatFink]

Are you guys gradually building the boost up to the desired level on the footbrake and then going WOT on the green? I usually go WOT from the start and let go when the light goes green timing it so boost is at least 6-10lbs. I'm wondering if the stall converter will "flash" a little better the first way?

I have MT/DR, I drive around the water, back up avoiding the water. Spin the tires up real well, before going to the line and staging I'll then test how much boost it will hold before breaking loose, then when I "feel" how much I think the tires will hold based on track prep, amount of heat I applied to the tires, I'll roll to the staging lights and hold it for all the breaks are worth.

 

[Quick6'n'-K.C.]

I do a nice burnout with lots of smoke. Then control the lights, 99% of the time i bring the throttle up to 1500 with the first set of lights tripped and wait for the other guy to bring down both sets of lights.

Once both sets of his lights are tripped, i give it enough gas to get the turbo spinning faster, but not enough to push thru the lights.

I set the second set of lights, and give it half throttle to get the boost coming up, since its slower to spool, if i floor it there is too much fuel and it actually spools slower.
So at half throttle it spools the fastest, once its around 12 or so, i floor it, let off the brake pedal and the car sticks to the ground.
It takes about another second or so to go from 13 to 26psi.

If it had a convertor in it, id just floor it and wait for the boost to hit 10psi, im sure the time from 10 to 26 would be quicker with a looser convertor.

BW