I am running 315/35/17 Nittio's on 17x11 and not having good luck with my 60'

These tires are not consistant, best 60' is 1.88 with the following settings:
Tire pressure 15
I am using HAL QA1 front 1/ rear 2
TQ arm set to 2 1/2 down
launching at between 3500 to 4,000

I am only able to start to hook if some big boy lays down some fresh rubber.
I know some of you have run these tires, what is your recommendations?
I was hoping for 1.7

Will a drag bar help this setup? If so, your recommendations?

I am also thing of going to ET streets for the track, but would like to do better with this setup first.

Thanks

 

any 35 series tires is going to be a challenge, just not enough sidewall.

i think your shock settings are off for a M6 on that tire.

1 is too loose in the front for a radial M6, the front won't extend high enough to take advantage of that setting and therefore it will immediatelty fall down very quickly and unload the rear end. having the backs on such a soft setting of 2 will only compund the problem as the front end will be able to easily drag the rear up when it falls. picture the a rocking horse with a kid on it, that would be a good idea of what your car is doing as soon as you launch it with those settings on a radial, that woudl also explain why it is so inconsistent.

I would honestly try 6 in the back and 4 in the front, you might be surprised at the results. Start with that and then work around it, you have to start stiffer and then play with it and see what the tire and track conditions will handle with that tire and your particular car.

for example. i only run as soft as 4 in the back with an et street dumping the clutch at 7,000 rpm with full drag suspension. i've only made one test pass on my nittos early in the year, i had the hals on 4 all the way around and the car did a 1.8 baby launching it.

 

Your tire pressure sound too low also, 15 psi may be good for a a big slick but a tire with a 35 series sidewall will cup and not use the center of the tire. Might want to try around 20 psi.

 

I run 19 psi in my 315's on a 9.5 inch rim and they seem to work great there . My suspension is a bmr tq arm set at -2 deg. stock shocks all the way around and front sway bar removed. I have an air bag in the right rear coil but never put more then 8 psi in it ( works better with et streets then Nittos).

I start off with a good smokey burnout, come out of the burnout still spinning some but not as hard as while sitting still. stop , pump the clutch a couple of times and then run through the gears just to get a good feel.
I stage , bring the revs to 4000( sometimes 4500 depending on track) and when the light comes on that you like to leave at , dump the clutch but dont mash the throttle all the way untill the car starts to jump out . when it feels like it is hooking , stick the gas.

THis pulls consistent 1.72's and on a good track day, as you can see in my sig with the 245x50x16 nittos leaving at 4500 she went 2 back to back 1.67's. These were with 4.10's and I now have 4.30's. THe 4.30's take a little more tlc and so far am only getting 1.75 to 1.78's but still et the same. On Et streets the 4.30's run away from the 4.10's

Oh yeah! my race wheight is 3726 at last years thunder shoot out and was pulling 1.70's weight is the same as then.

 

Thanks for the help!

I have tried more air presure but it did no seam to help
I have tried different shock setting, but not sure where it needed to go to make a improvememt. (normaly I run fronts 2/ rear 4)

I will try your recommendations Friday night
Fronts 4
Rear 6
Tires 19psi
Dump at 4,000 hook then stick the gas

Now if its still is not hooking what should I adjust first?

I really appreciate all your help.
Maybe I can run a 1.7? 60'
Thanks Bob

 

what is important is to only adjust ONE thing after each pass, nothing more. if it takes several track trips to get the car dialed in, so be it.

for example if after the first pass you feel the rear could have squatted more, then just soften up the backs one click, two at the most and leave fronts alone.

what i do after a pass is sit there and think ok what did the car do exactly and approach any adjustments i make using logic and careful thinking. you have to see ahead as to how the car will react to the change you are about to make and if its inline with what you feel the car should be doing to improve.

 

SilverGhost

I try to make only one adjustment a time, but the car/me is so inconsistent that it is hard to see a really change. I will try running the same setup a for a few passes and see how that works.

How should the LCA be compared to the ground, mine are on the lower hole and my car is seating about 1 inch lower than stock? The LCA is sloping upward about 10 degrees going forward. If I put them in the middle they will be level.
What do you recommend?

Will a drag bar help at this stage?

 

I did not notice, is your fron sway bar off? BIG!!! difference.

 

i don't have much experience with relocating LCA's, i never had relocation brackets in my 10 bolt days. like anything, move them a notch and then make a pass, see what it does.

a rear anti sway/drag bar is *probably* overkill for your application. IMO they are really more for cars running slicks that come out of the hole very hard. I love mine, it helps my car alot, but i don't think i'd need one if I didn't launch at 7000 rpm on a slick like i do.

i think the hal settings are going to be the key for you with this radial. get to the track and start playing with the settings, one change at a time. as for being inconsistent..well its an m6, if your driving isn't where it should be then just work on it or have someone else drive it for a day. I do this for people all the time that want their car dialed in with a good driver, there is no shame in it. an M6 on a thin sidewalled radial is a bitch, don't let anyone tell you otherwise, but you'll get it.

 

18psi is perfect IMO on 315 Nitto DR's.

 

I think my driving is OK, but I could use more runs under my belt. Once it starts hooking more consistent I will be able to work more on my launch technique.

Aint Skeered, I have removed the sway bar

Next mod is going to be
-HC AFR 225, FM13 or G5x? and Fast 90 intake/TB.
-track wheels and tires

I am try to get my car dailed-in before I go any further.

Thanks for all your help, we will see how it work tommorow.
Bob