gz91rx7

The car: 89T2 lots of mods.
Big 17" rims with 245's that are brand new.

Last time out I ran horribly and it was due to my huge tires with mad grip.
So I got a set of 91 na wheels for the rear.
The downside is that they are 15's.

my questions are;

1. Should I get the same rims for the front so I dont have 17's in the front with 15's in the rear?

2. What size tires should I run on the 15's?

3. Are the 15's to small?

here is the link to my mod list for anyone who may want to see it.

http://flightsimmers.net/airbase/pla...gzmodlist.html


Thanks,
Josh

gz91rx7

bump

vosko

iTrader: (4)

you can never have too much grip.... you should have enough power to spin 245/45/17's.............. your not launching hard enough

gz91rx7

Ok vosko you got me all confused. I thought that you said I should get some smaller tires?

gz91rx7

And no your not driving it

vosko

iTrader: (4)

umm smaller why ??? the more traction the better! what happens when you launch with those 17's. unless your gonna put 15" drag radials on those 91 rims i would stick with the 17's . wider tires = better traction

gz91rx7

Well I stick so much that my rpms drop to far and there goes the launch

Rpeck

Give it more gas. Like Vosko said ... you should be able to spin those. .. You want to be right on that fine line; as much power as you can get just before spinning them. What RPM you launching at?

gz91rx7

I am launching at 4500-5000. On the street they spin well but the damn track is so sticky the just grip and my rpms drop!

vosko

iTrader: (4)

rev at 7000 rpm. i raced my TII so many times. i never broke ANYTHING. TII's have VERY strong rears and axles!!! you shouldn't break anything except into the 13's or 12's

another thing. i don't care what people say. when you heat up street tires they get stickier. try lowering tire pressure and doing some nice brakestands. that should get a very nice 60 FT..... it worked for me

gz91rx7

vosko you have to be kidding me! 7 grand?
Will I even have a clutch left?

vosko

iTrader: (4)

i thought people were nuts that launched that high too but it works!!!!

actually launching that way is easier on the clutch than slipping the clutch. i did that on my stock clutch in my N/A . that clutch is still going to this day. my six puck clutch in the TII is still good and it saw tons of 7000+ rpm launches and drag racing yadda

your driving an rx7 launch high and you will get a good launch!!!! i've been there done that. i went from a stock TII with 15.3 @ 88mph to 13.7 @ 100mph

how well you can shift plays a pretty good role in your time too. these things will all come together with practice

suprfast7

you should put the 15s on the front the 17s on the back hit the burnout box and launch at different RPM ranges untill you find the best one for your car to launch at. And make sure your not burning your clutch besides the tires. new clutch might help if you need one

rx-7fc

vosko what did your na rx-7 run in the 1/4 mile the best i did was 16.6 and 60' 2.3 or 2.4 i think and the last time i went my tranny got messed up but put used one in and going soon so any tips like what rpm's to sift at and good rpm to launch at i have act clutch street/strip my mods are road race header,hks exhaust, ported 89-91 intake manifold ,8.5 msd wires,no avc, TB mod and the VDI is not working and i have a 86 gxl

gz91rx7

well I can say that my car wont ever see 7 grand before I take off. But I am just wondering what everyones thoughts are on putting my 15's on the rear with some good tires? and will it matter if I still have my 17's on the front?

rx74prez

haha, yeah i cant get myself to launch at 7000 rpms either. Check the weight of the rims. The weight has alot to do with it. With lighter rims and tires, you should be quicker because you have less rotating mass. Much like a lightened flywheel, helps you to rev quicker. Same principle, less mass = quicker rotation. I know the yokohama a520 are pretty good tire. Oh and also try slipping your clutch with the tires you have....I know it is bad for the clutch but you shouldn't bog like you said were. This is just what I have read and tried on the street, I am going to the 1/4 this weekend for my first time, so we will see how my advice is put to my own use, probably will be pretty ruff the first time, but i can drive pretty damn well, so i am damn excited. Hopefully I will be in the high 13s low 14s with my setup.
Chris

vosko

iTrader: (4)

i ran 15.9 @ 86mph with a 2.2 60 FT. this was back when i still sucked at drag racing LOL. my car had pacesetter headers,bonez cat, stock catback, intake. the new owner took out the ac and power steering and ran a 15.4 . i don't know his 60 FT though. i launched my N/A at 8000rpm * you should launch at 7000rpm. n/a's have no torque so your not gonna break anything. the higher i rev'd each gear the faster the time i got. i would shift at 8200 rpm. your limited to like 7500rpm though. in my experience that is what got me the fastest times..... if you need anything else let me know or pm me

vosko

iTrader: (4)

SISSY! your not gonna get a good time unless you launch hard. oh well.... my POS ran 13's LOL

gz91rx7

LMAO!! Vosko you crack me up. I will launch high but damn that is just nuts!
Thanks for the info Vosko

dre_2ooo

7k and drop the clutch


































Please dont take this seriously

vosko

iTrader: (4)

how much does anyone want to bet me if he launches at 7000rpm he will get a faster time.... i'm waiting

jspecracer7

If you launch at 5000 and your rpms drop, then you're not launching high enough! Try 6000 then 7000. With my 275 Nitto's on 17" rims, I launch at 6500 RPMS...

Ryde _Or_Die

I know he will. If you want the best time you need to launch at high RPMs in rx7s. Hell, I launched my friends VR4 at like 6000, lol. I got a better time than my friend did in his own car by 3/10 of a second. And it was my first time driving. Remember your driving a high revving sports car. This isn't a civic.

Ryde _Or_Die

Oh and I thought I'd add:

If you are so worried about breaking anything, your car shouldn't be at a track, IMO.

MazdaRx7Racer4Life

hahah, I guess ive been doing it all wrong, i heard the rexs were good for high revs, so ive been launching probably like at 10k.