What is the most concise way to dial 60's in? I don't get more than 10-15 passes per night, so getting the 60 dialed has to be quick.

Current best is 1.70, launching at 7200rpm w/ 9psi in the 23x8x13 slicks. Sometimes i just blow the wheels off and spin really hard off the line, and sometimes it hooks well.



Would i be best off to start playing with RPM first, or tire pressure first?



Setup is a 1990 hatch w/ heim joint radius rods, D16A6 @ 300whp/267ftlb, M&H 23x8x13's on lenso's. Usually do about a 5 second tire warm-up in 2nd just outside of the water box. Pre-loading and launching at 7200rpm (FTL) w/o anti-lag.

any points or suggestions are greatly appreciated. i would love to see 1.6's consistently.


quick pic of the car in action

 

9psi is more than likely too much pressure for starters...... I would try 8 and go down until you see the car get slower


10-15 passes a night **** you would be lucky to get 3 at my local track, 10-15 passes I would think you could dial in just about any car.

 

10+ passes on a good night... last time i only got 4

so you think my time is better spent changing the tire pressure first.. hmm

at what point would i want to stop removing tire pressure at start lowering the launch RPM? i guess once my rims start pinching the slick. lol

i wish i could understand how someone can pull a 1.3 60ft. even a 1.5! that is amazing stuff

 

Stop removing air when you see the 60's get slower again, then put them back to where you got your best times from. Seems like the trend leans towards 6.5 to 8 psi cold.

How is your alignment? Corner Balancing? Traction Bars? Suspension Setup?

 

Sounds like you are spinning. Those things should pretty much dead hook. I a friend cut a 1.57 60' all motor on those same slicks. He was at 3psi hot. I run anywhere from 4-6.5 nothing more then that.

Also a practice launch would help.
do a burnout, pull up a few feet. Rev it up and practice the launch. It will clean the slicks off and help give you a feel whats going on.

 

tire screws? I would be terrified to run that low psi with or without.... IMO thats asking for a date with the wall

 

^^ ha yeah doesnt sound like a good date to me.
but at my old hometown track in VA we would get like tops 3-4runs on a friday night. 10-15 is like a months worth ha.

 

ya, 3 time trials tops at my track. 6.5 psi seams to be the sweet spot for me. heard more than once that dead hooking is bad. i've seen it myself. like previously stated, start at 8 psi and go down until you start slowing down again. you need to do consistent burnouts and stage the same every time if you want consistency. tire pressure has everything to do with temperature. if you set 6.5 psi cold then do a narly 10-15 second burnout they will be hotter than if you do a normal 2-5 second burnout. do the same thing every time and it will pay off.

 

What diff? lower the pressure a bit, 7-7.5 on that size works well for me. I cut low 1.7's open diff in a 2600lb car. Get some sort of launch control for it. Launch control IMO is the only way to cut consistently good 60's day in and day out. What does the car weigh?

 

keep in mind that the 330 is just if not more important in our cars. i have had many 1.7s 60s but depending on the 330 can really make up the difference at other end

in other words. u can have close same 60s but 330 can change quite a bit with diff tire pressures, u want to get out the box (spinning alittle) never bogging. this will help get the 330 better

hope this helps

dan

 

thanks for the ideas everyone

setup is as follows
weight: 2200 w/ driver
diff: MFactory LSD
turbo: holset HE351CW

best trap 118mph, best ET 11.79

ill keep the burnout consistent, start with around 8psi in the slicks cold, and work my way down until i start to get slower out of the hole.

when i find the sweet spot for tire pressure, will that remain consistent if i start to change the RPM im launching at? i guess there is only one way to find out..



when i first got this setup together i was launching using antilag, about 16psi off the line, but since then ive switched to straight FTL and the car seems to spin the tire a lot easier and seems to have more power coming out of the hole.

i also think its worth trying to run outlaw so i can try a freshly VHT'd surface instead of one beat up by street tires

 

16 psi of boost at the line is alot IMO for that size tire. Just for comparisons, I have a D16Y7 setup in my car, Makes 330/260 in DD form (how I run it at the track too) And weighs 2550 w/me if i take my work crap out of it. Open Differential, running 7.5psi tire pressure on MH 23x8x13's my best run was 11.54 @ 118mph 1.70 60' ,7.4x 1/8th mile. Launch control set at 5000, making ~6psi when i launch. )just throwing this out there as the cars are similar motors, same slicks, etc. It just takes time and minor adjustments. I'm lucky to get 6-7 runs at an event, and thats when I go 3-4 rounds of elims

 

thanks for chiming in. ya our setups are fairly similar. interesting how much lower your launching rpm is.

i may have to try lowering it.

it sucks because every time i go to the track i get obsessed with besting myself, and i dont want to play with my launch in case i farq it up and waste a pass. lol

 

If you're not making the adjustments to go faster, or get it dialed in better, then you are wasting passes IMO

 

I think the 3.083 1st would help you out some Dan.

 

money money!



well i tried many things at the track, and i think it is spinning through first just too much. if i launch at 7000rpm it will drop 1000rpm and within .3 seconds its at 7800rpm

only got 5 passes. heh

i think antilag is just overwhelming the tires

i got an HD video as well which helps a lot to listen to

http://www.youtube.com/watch?v=RjGiEPQiBAE

 

Lower the launch limiter??? I launched at 5-5.5 on those slicks making like 8psi at the line

 

Im really struggling with 1st gear wheelspin as well.

My setup is Ep3 with K20A2 strokered to 2.2, Rotrex charger & water/methanol injection on a stock gearbox.
Power is 494bhp at the flywheel.



I run M&H 8.5/24.5-15's usually with about 8 -10 psi, I have kpro so normally set launch control from 5800rpm - 6400rpm.

Best 60' is 1.74.
Pb is 11.80 @ 119mph with wheelspin. Im sure my car will run low 11's if I can get the 60' dialed in.

Has anyone any ideas how I can get my times down ?

Thanks Dougie

 

To the OP....

You can eliminate a lot of your problems by having a good suspension. Whatever you have now is not working for you. It's obvious in the video's. The initial snap is killing you causing your tires to just spin. My guess, bad weight transfer through the chassis.

 

After watching the video I would say let it hit the limiter a few times in 1st before shifting. That tends to help a bit as well. Also I would try 5500 launch between 6-7.5 tire pressure. Good luck

 

i agree, my suspension is not optimal. AGX's on H&R sports... that is going to be upgraded for next year, i just need to decide if i should go with the 96 civic hatch or stick with the 90 hatch... hmmmm

thanks for the numbers.. ill try starting off around 5000 and work my way up.




going to the track tonight, the weather is iffy so i should get quite a few runs in (bad weather reports keep the ricers away. )

wish me luck on cracking the 1.6 barrier.

 

well, i tried what seemed like a thousand different combinations but i couldnt get into the low 1.7's! the car is torturing me!

the car would blow the tires off at even 5500rpm with 8 pounds on antilag. with 8psi in the slicks.

i broke an axle for the first time ever, coming out of the burnout box. it just so happened i was on TV when it broke!! lol thank god a local named Gary was there to help me out with a replacement axle! i owe you one dude!

i could try going lower with the slick pressure but it really does not feel safe. the car gets some wheel hop as well at the end of the burnout with lower tire pressure.

at 5000rpm, the car wouldnt bog off the line but rpm would drop to 3700 and it would pull fairly linear out of the hole and i still had gear left out of the 60. that netted me 1.8's

5700rpm the car would spin right off the line

5500rpm the car would bite well and spin the moment it hit 20 pounds

5250rpm was decent, but still spun once the car built more boost, but didnt seem to leave as violently as higher RPM launches




its times like this i wish i had been doing this for more than two years... lack of experience is killing me!

next year its drag suspension + a new set of 24.5's im thinking...

 

Do you have gear dependent boost? Most cars I have tuned at the track 20psi in first would be way too much.

 

Try riding the clutch off the line a bit. dont drop it, but linearly let it out off the line. Maybe 5500rpm, ride the clutch a hair, and 7 psi in the tires?

He's only making 300whp, those tires will hook that.

 

never got down to 7psi. stopped at 8psi when it started to wonder a lot and hop coming out of the box.

i am guilty of a preload to dump style launch

ill try riding it.

ill try anything to get these 60s down.