Best boost to launch at?

SYCLONE#1531

SYCLONE#1531

'MOFOFAST
Im going back to the 1/8th mile drags at Paradise drag strip (CALHOUN GA) in a few weeks. I have installed some new MT drag radials on the rear. What PSI does everyone normally launch at? my previous 60 fts were 1.79 with street tires launching at 10psi +. Will lower boost launches achieve better 60 foot times?
 
Six-is-Enough

Six-is-Enough

Use to do a little Boost
Re: Best boost to launch at?

Need more info about the truck. Mods? Stall converter?Stock turbo?

But I would start out were you were with stock tires and just play with it up and down.

Example : 1 st pass 10 psi launch- ask your self if it spins or not.

If no spin try 12 psi. If spin try 8 psi.
:tup:
 
DanenGraham

DanenGraham

Big in the rear
Re: Best boost to launch at?

Think your going to have to just find out. Try a 0# launch, try a 5# then 10+ if your brakes will hold it. Not sure on your mods if any. But when my truck was stock, at the track with street tires anything over 5#'s would make it go from low 1.7's to mid high 1.8's.... IIRC i even pulled a 1.69 once. But its going to depend on lots of things. Temp, track prep, if you roll through the water box or go around it. On the street I could do 10-12# launches and it would hook hard, no spin just a chirp.

Last time it ran down the track, was at Nats a few years back, and anything over #0 just spun really bad. But thats shit ass used tires, and no bed.

Good luck.
 
SYCLONE#1531

SYCLONE#1531

'MOFOFAST
Re: Best boost to launch at?

not sure of the conv? It will foot break to aprox 2600 rpm. My previous times were 8.5 at 80 mph in 1/8th totaly stock minus fp regulator (set at KB recomended fp). I have now added a 3 inch mandrel bent cat back with Borla xr1 muffler, conv lock up switch, air foil, pas side mounted 9 in kn filter, walboro f pump, KB street chip with 104 race fuel to keep from knocking, Electric fan, AC DELETE (RPMs KIT), no spare tire!!!:lol: New taylor wires and plugs, no driveabilty problems. I am hoping to get a 7.9 out of it with the new minor mods.
 
NecroWolf

NecroWolf

lost marbles member
Re: Best boost to launch at?

as much as you can without losing time on your 60ft, could be 0 or 10 or more
 
M

Maverick87

Member
Re: Best boost to launch at?

do you have any type of data recording equipment? If so log and watch for wheel spin. It will look like a hump in the first few frames of the launch. Adjust till it doesnt have the hump. With m/t you should be able to get up around 8-10 psi. Even with running 104 I would be careful of the k/b chip. I doesnt pull timing with knock.
 
DanenGraham

DanenGraham

Big in the rear
Re: Best boost to launch at?

cloneman315 said:
this is were the 2 step works well
Click to expand...

No stock, or even lightly modded truck needs a 2 step.

Its an auto, with a trubo. you press the brake and if the correct stall/turbo is in the truck. It should give you a wide range of how you want to launch. With out over heating the trans. Hell the only time my trans goes up in temp is if i get on the hwy for more than 15-20 mins 70mph plus.

And you dont have to mess with anything, but the brake and the gas peddle.

How many people on this board, braket race and have the mods to warrent the 2 step? Not many.

If anyone, has the vid of me at the track with the bed off, im damn near the only person that got up to the line, got the brakes built up. and had it ready to go in a matter of seconds (i try to look at the other guy and see how long its going to take him to get to the line so i can start to stall it up... not build boost to fast and start cooking things. Unless your racing pro-mods, you wont see people out there trying to play games as they are staging.

Most of the people on here, sit, wait for the green then try to get the perfect launch 2 secs after the reaction timer.. Come on, learn how to do it smoth, fast, and not look like you have no clue whats going on to anyone else at the track. And all of my runs had decent R/times but i got to play around each launch with out touching the truck.

The more basic the set up is, the less that can go wrong. And we already have lots of things that can go wrong
 
JSM

JSM

Active member
Re: Best boost to launch at?

DanenGraham said:
No stock, or even lightly modded truck needs a 2 step.
Click to expand...

No car NEEDS a turbo either.

But unless you have tried a 2 step you might be suprised how well it can let you tune, adjust things and do the same thing everytime.

First time out with my 2 step I cut a .020 light, 60' times were all within .07 or so seconds.
 
turbodig

turbodig

Active member
Re: Best boost to launch at?

SYCLONE#1531 said:
Im going back to the 1/8th mile drags at Paradise drag strip (CALHOUN GA) in a few weeks. I have installed some new MT drag radials on the rear. What PSI does everyone normally launch at? my previous 60 fts were 1.79 with street tires launching at 10psi +. Will lower boost launches achieve better 60 foot times?
Click to expand...


It'll entirely depend on the track prep.... as others have said, try what you ran last time- if it hooks, add 2-3 psi. Repeat the process until you spin.

Make *sure* that your rear tire diameter is reasonably close to the front- otherwise, it'll slow you down a bunch as the transfer case fights itself. Tire size can vary a surprising amount with changes in tire pressure.

The Mickeys like heat, despite what they tell you. Pull 'em in to the water box, put the trans in low, muster up as much boost as you can and let 'em smoke. Watch your tach so you're not bouncing off the rev limiter.
 
Six-is-Enough

Six-is-Enough

Use to do a little Boost
Re: Best boost to launch at?

Make sure if you do a awd burnout make sure you get tires plenty wet. Wheel hop will break stuff! Pull through water then back up and pull through again.

BTW what launch psi works one day might not be the best the next time. I vary my launch psi 5-15 psi. Somedays it likes 15 psi and will hook like a monster. Some time it needs 5 psi to avoid wheel spin.:2cents:

You should be shooting for high 1.6X 60' et's.
 
cloneman315

cloneman315

Active member
Re: Best boost to launch at?

yeah for sure you must of never used a 2 step before,it is less abuse on the trans,and lets you get a perfect launch every time.makes it so you can adjust for different track or street conditions.and all you have to do is turn the pod,I will bet anything get two of the same builds together and one with a 2 step and one without and I will bet you the truck or car with it is very very close every time more so than the one without it.And even more so a stock truck will run better with a msd ignition on it anyways.
 
BoostedSUV

BoostedSUV

Active member
Re: Best boost to launch at?

Yep... As high as you can get the brakes to hold boost and launch with out tire spin. There's no set number, every track and track is different depending on conditions. I've launched mine around 13psi and gone 1.69 60ft on street tires. Its all about what the track and your tires will hold...
 
JSM

JSM

Active member
Re: Best boost to launch at?

What should you do if you spin at 4psi?

Nevermind, fix the damn suspension setup.
 
JSM

JSM

Active member
Re: Best boost to launch at?

cloneman315 said:
turn the 2 step down,if i guess you have one of them worthless things lol
Click to expand...

Yep, got the 2 step with selectable.

I was joking knowing only Jeremy would get it. I have only run 6-7psi of max boost so far.

Initially at 4psi it was spinning at most tracks, few conversations with jeremy and a change in how the 4 link was setup and it got much better.

Hopefully this year we can see what 10 or 15psi does.

Back to the thread you need to keep a record somehow of tire pressure, launch psi, rpm notes on track and dial it in.

Change 1 thing at a time until you find a combination that works best.
 
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