JDM74

I need some pointers. Best 60' to date is a 1.72 which I think is a fluke. My average 60' is low 1.8's. I am attaching a link to a video of a typical pass with a 1.83" 60' time. Here is the info from the time slip:

1.8386 60 ft
5.1462 330 ft
7.8341 1/8 ET
92.23 1/8 MPH
12.0367 1/4 ET
118.14 1/4 MPH

Here are the mods to the car:

Engine:
Futral Racing F13 cam shaft 230/232 duration .595"/.585" lift (intake/exhaust)
Melling hydraulic lifters
TSP 7.40” hardened pushrods
Yella Terra 1.7 ratio roller rockers
Patriot Performance Ti retainers
Patriot Performance Golds double valve springs
Stock Heads slightly cleaned up
Rollmaster double roller timing set
LS6 ported oil pump
180 degree thermostat
LS6 PCV system valley cover

Induction:
Ram air modification (involves cutting the floor out of the air box so cold air is drawn from in front of the radiator)
K&N filter
TSP Clear air lid
Home ported throttle body
LS6 intake manifold with EGR deleted

Exhaust:
Stainless Kook’s 1 5/8” race longtubes with off road Y pipe
3” Dynomax intermediate pipe with QMH electric cutout
Dynomax Ultraflow muffler with 3” turndowns at the bumper

Fueling:
TNT, Nitrous Express, and NOS wet shot, 50 horsepower. Purge in the cowl, MSD window switch, pressure safety switch. Bottle mounted in the spare tire compartment. Control switches mounted in the console.

Drivetrain:
RAM VDS clutch with 980 disc, Adjustable master cylinder
Hurst Pro Billet shifter
Denny’s Nitrous Ready driveshaft with 1350 u-joints
Moser 12 bolt with 4.11 gears, spool, 33 spline non-C-clip axles
Chassis:
SLP subframe connectors
BMR tubular K-member

Suspension:
QA1 12 way adjustable shocks all four corners
275# QA1 springs on the front, stock springs on the rear
Stock upper A-arms
BMR tubular lower A-arms
Stock front swaybar
BMR adjustable pan hard bar
Stock torque arm
Global West spherical bearing/rubber bushing lower control arms with relocation brackets welded on the axle.
BMR rear swaybar

Wheels/tires:
Street: Silver painted ZR1 replicas 11” rear with 315/34/17 Sumitomos 9” fronts with 275/40/17’s
Strip: Stock 16” wheels with 245/50/16” Daytona’s front and 255/50/16 Mickey Thompson ET street radials rear

QA1's are set at 0 in the front and 6 in the left rear and 7 in the right rear. Tire pressure is 15 cold.

This is the second run of the day:


http://s140.photobucket.com/albums/r...rrent=jdm2.flv

Can any of you really good 6 speed drag racers give me any help? I know my tire/rim choice is not optimum but the car is hooking off the line so traction doesn't SEEM to be the problem? Front shocks too soft? I am at a loss.

cainsw

iTrader: (11)

It sound like you need about 1000rpm more on the launch. Watch and listen to the serious bog on that launch. Nice air with those heavy front street tires though. But 6 speed car really needs to lose the drag radials and get et streets. Also get you some 15x3.5's for the front. You will be in the mid to low 1.6's with those two changes alone. Been there done that! Good luck

bowtierodder

iTrader: (3)

pulling the front street tire with 1.8 60 ft. ? thats impressive

cainsw

iTrader: (11)

That is bad ***

camarokid94

iTrader: (2)

what is your RPM at launch. deff needs more RPM and maybe some clutch slip. good luck man

6SpeedLT1

i would make the nitrous come on a tad lower ..... it will keep it from bogging....

JDM74

Well, I am already launching at anywhere from 5000 to 6000 RPM, lol. Looks like clutch slip is my only option now. BTW that is a NA pass. No nitrous.

fitz98ta

iTrader: (29)

you might try tightening up your front shocks some, i noticed that the front end comes up and goes right back down. So tighten the front up and play with the rest of your configuration to get it to hook and HOLD the front end up instead of bouncing up and back.

Also are you running with your front swaybar hooked up? from the video it doesnt' look like it, but i saw in your mods you still have it on

kezy219

iTrader: (2)

bad *** car either way. =)

AINT SKEERED

iTrader: (2)

I am having the same problem as you . my 275x50x15 mt drag radials are hooking to hard and my spec 3+ wont give. Between the 2 (tires and clutch) I went from 1.59 avg. to 1.70 avg dead hooking but bogging. I am going to try going up from 17 cold to 20 cold to see if it will allow a little spin. I leave at 6500 rpm's though to make up for an aluminum flywheel.

I had the aluminum flywheel also before with regular spec 3 but that clutch allowed just enough slip to still not bog.

I think you can make yours do better with a little higher launch or a little more air in the tires. care full though, mickeys either hook or dont, its hard to find that happy medium

JDM74

Yeah, the front sway bar is off on the strip. I think I am going to try tightening up the front shocks some and hold the front end up. That a ride out the clutch a tad and see if that helps.

Gary Z

Obviously, tightening the shocks can’t hold the front up if you continue to lift a wheel. I agree it might help however, perhaps by changing the natural frequency of the suspension. Multiple factors interact in a complex manner to produce a good launch. You can discover an effective combination by experimenting. Understanding exactly why that combination works is another matter. My stuff seems to work best with the front QA1s at position 3 (2 clicks).

BADSZ28

iTrader: (39)

Dude, you really need a torque arm in that thing. Your rear is most likey binding up not allowing the car to go till the rear is fully loaded. Once loaded it hits the suspension hard pupping the front up. Mine did the same thing. Pop the front a sec, then fell on it's face dead hooking. I did a TA and my 60s went down and car pulled harder out of the hole. Still bogs, but not as bad. I will need to work on slipping the clutch out the hole. I went from besting 1.8s to 1.6s just from the TA swap.

Sharpe

iTrader: (7)

WS6HUMMER

iTrader: (19)

Listen to Cainsw, he helped me. He watched my launch and told me RPM wise where I needed to be, then he reccomended firming up my front shocks (I have QA1R's with 275# springs also). So I remembered Madman telling someone 4 up front and halfway in back. I set the fronts to 4 and the rears were 6 & 7 just like you have done. The next pass I made got me my best ET 60' and it pulled the front wheels.