last year I had few runs with my Z on stock tires with only INJEN CAI .. most of the runs ended in high 13's , with the best time of 13.70 which I am very proud of...
now , few days ago , I went again , to the same track , and had some runs with mods ( in my sig ) + Dunlop sp8000 275/35 in the rear ( 25 psi ) and stock 18 wheels + stripped trunk...
I was shocked that the best I ran that day was 14.2X
I dont know whats the problem... my tires were spinning in the 3rd and 4th gear , and I dont mean chirping , they were actually spinning to the point that when I shifted into the 4th gear , I got a little fish tail ... my friend had 2 runs with my Z and he got 14.7X , and 14.6X
I know my Z runs better with the mods , but why I got some bad times ?? ... is it already time to get some slicks ? I really didnt think so...

 

it sounds like a combo of the weather and lack of traction, if the track prep is weak then there is nothing you can do about it. If not then you just need to learn how to be a little smoother with your throttle during upshifts.
As far as slicks, depending on the tire you are running now and at your power level you should be fine. Slicks of course will drastically reduce your 60's and alleviate any upshift wheel spin going down the track. Slicks are fun,but they do rag on the car a lot more if you use them to their potential. A good street tire is enough if you learn how to drive on them. the 18's are probably not helping either.

edit:19's(although i bet they look cool as hell) pic?

 

hmm .. I think Im gonna get the slicks and check again.. I was really hoping for mid/low 13's with the stuff I have now...
with the plenum , headers and slicks I should have no problem getting into 12's...

as far as my 19's I still dont have them , and Im not sure if im getting them anymore , I paid the guy 3 weeks ago ..

anyone knows if I can go 15's the rear with the slicks ?
anyone went this route ? or should I just go for 16's ? whats recommended ?

 

sorry about the wheels bro.

as far as track tires, it might be beneficial for you to go with a 24.5" tall m&h to give you more gear, but i only see them for 15" wheels. I dont know if you will have brake clearance with that.

when Sith ran his 13.0 he had 23 inch slicks on 15s. hope this helps, if i were you i would pm him and see what he can tell you.

 

thanks for the help
I just PMed Sith to see if I could fit 24.5 X 8.5 X 15 on the Z , if yes , I'm gonna buying them... tired of wheels spin..

 

i saw some on jegs,unless sith changed to smaller than stock rear rotors, you should be able to fit 15s on yours too since they are the same for touring and enthusiast. maybe you can find some 15" take off nissan wheels with the same bolt pattern to mount them on. I would think a 7 to 8" wide wheel will work perfect if there are any. I use to have 15x7 ranger wheels when i first racing on slicks for my stang

 

if I get the 15's in the rear , do I stay 18's in the front or do I change all 4 wheels ?

 

you can always buy smaller lighter wheels for the front for weight reduction, but it is not needed. the smaller tire diameter in the rear will probably mess with your abs or traction control. sith should know about that though. I would use it as a dragstrip only set up. I usually bring my jack and slicks to the track and changet them there.

 

yea , I dont plan driving on them , nearest track is about 1 hour away from me + I dont feel suicidal...
so I guess its better to get all 4 wheels instead of only 2 rears... gotta hit some junk yards soon..

 

i just do two, try ebay. or you could buy two welds or centerlines that will work.