Buying Drag Radials soon- 26 or 28 inch tall tires?

[BandRcAMARO]

Car is a 2010 m6 with cam, ported heads, fbo, stock 3.45 gears.
I ran the car this past summer and i was running high 12's at around 118 with my current street tires. They are 305/35/20 Cooper Zeon's so just over 28 inches tall. As I get to the end of the 1/4 I always have to shift into 4th to not over rev in 3rd. Always like half a second before the finish line. I bought a 17 inch drag wheel setup and am wondering if i should go with 26 inch tall tires so that I can shift into 4th earlier or stick with 28 inch tall tires. I am pretty new to drag racing so any advice will be great.

[frankwjr]

what rpm are you shiftin at? when I had my 3.45's never shifted out of 3rd, mods in sig.

what cam r you runnin and who ported the heads? and who put the tune on it? lot's of Q's, put your mods in your sig.

r you going to change the rear gears? bigger cam usually likes at least 3.91's on N/A combo's..made a massive difference in the cars performance.

any other mods to the drive train? these cars will hop so T/A's minimum..

post your best time slip, 60 is prob crap but top end #'s can tell a lot...

gettin out of the hole with out DR's is impossible..I may actually move to slicks..I'm told they behave better on our stick vehicles..

can"t be afraid of the car, these mutha's are tough...my last trip to the 1/4..times in sig...good luck!

5k launch..7k shift...gotta slip the clutch and try to keep the rpm's up without blowin off the rears..

nice pic of the rears hookin.

[jrhagen]

DRs are for autos, slicks are for sticks..
Get Hoosier 28/10x17 slicks and have fun replacing rear suspension and driveline parts.

[07-SRT]

Originally Posted by BandRcAMARO

Car is a 2010 m6 with cam, ported heads, fbo, stock 3.45 gears.
I ran the car this past summer and i was running high 12's at around 118 with my current street tires. They are 305/35/20 Cooper Zeon's so just over 28 inches tall. As I get to the end of the 1/4 I always have to shift into 4th to not over rev in 3rd. Always like half a second before the finish line. I bought a 17 inch drag wheel setup and am wondering if i should go with 26 inch tall tires so that I can shift into 4th earlier or stick with 28 inch tall tires. I am pretty new to drag racing so any advice will be great.

Top speed is around 113 mph in 3rd gear if I recall. I'm i the same situation.I have 305/45/18 which is the same height as stock and I have to shift into 4th as well because of the higher trap speed. If you keep 28 inch wheel probably need to go to 4.11 gears

[QUICRNU]

Originally Posted by jrhagen

DRs are for autos, slicks are for sticks..
Get Hoosier 28/10x17 slicks and have fun replacing rear suspension and driveline parts.

I agree! And I have some for sale!

[BandRcAMARO]

The cam is a TSP stage 3, 231/236 111lsa. Heads ported by livernois motorsport here in michigan, car is full bolt ons also and tuned by Dr. Phil. No suspension mods but I am planning on doing the trailing arms and also the toe links to try and reduce wheel hop. I might go to 3.91's eventually but for now I dont think so.

I shift at 7k and still have to shift right before i cross the 1/4 line. I tried holding it but I dont like going much past 7300 rpm with a bigger cam. I might go with slicks on the rear 26 inch diameter and some bias bly front runners also. I think with the smaller diameter I will be able to shift into 4th a little earlier and when I go to 3.91's eventually I'll go with 28 inch diameter tires.

Edit: Forgot to add that I have a Mcleod RST twin disc clutch.

[BandRcAMARO]

Reviving an old thread, but I am getting ready to buy tires. Someone chime in. To me, it makes sense to get 26 inch tall tires so that I can shift into 4th earlier instead of right as I am about to cross the finish.

[WHAMMO]

Im in the same boat, same cam LOL! Im like 80% set on 26" tires. I think its the best for car under 700hp, but it depends on gearing. Since our gearing sucks, 26inch is the way to go, I think. Too bad they do not make the 27 tire anymore...
What size you want to run on what rim?

[BandRcAMARO]

Honestly I think some manufacturers do make a 27 inch tall, not sure what sizes though. I have Racestar 17x10.5 inch wheels for the rear. I looked it up and with a 26 inch tall tire our 3.45 gear would technically be like a 3.73 gear. I think with that we should be shifting into fourth a early enough not to loose any mph on the top end.

[hillshooter]

I didn't see where anyone else above me mentioned this but you can't run 26" tall tires. It messes with the computer and you will get dash lights, beeps and ABS. this disables a bunch of stuff in the computer.

you technically could run a 26 rear but would also have to do so in the front. You cannot have more than .5 difference(ballpark) in the height of the front VS rear tire.

Also if you have lowering spring these tires will be bringing you down another inch.

[BandRcAMARO]

Originally Posted by hillshooter

I didn't see where anyone else above me mentioned this but you can't run 26" tall tires. It messes with the computer and you will get dash lights, beeps and ABS. this disables a bunch of stuff in the computer.

you technically could run a 26 rear but would also have to do so in the front. You cannot have more than .5 difference(ballpark) in the height of the front VS rear tire.

Also if you have lowering spring these tires will be bringing you down another inch.

I hear you on all that, I think if I pulled ABS fuses I should be fine for a few 1/4 mile trips.

[WHAMMO]

I will run 26 in the front too. I want to roll on those 26" all summer. Weekend car...I like the Toyo Proxes TQ

[WoodBoss]

I would do the 26" Tires in your case.

[BandRcAMARO]

WHAMMO,
Let me know when you get those and make passes, I would like to know how you like riding on 26 inch tires and how you did in the 1320. I still have about 2 months before I get mine so you will probably get yours first.