trey.hutcheson

iTrader: (2)

Well, technically, it would still be helping his trap

What's the top speed for 4th on the non-revups? 108? 112? I can't remember.

Let's just say it's 112. Then say hes running a tire that drops that max speed to 108. So if he's shifting to 5th, he's trapping AT LEAST 108. That's a nice jump from 105

PS. don't take this post seriously

VeeTec

I don't get out of 4th, even with the smaller diameter tires.

The same rpms make for less speed.

I tell you what, next time I go to Steele, I will run both again, and video document the outcome. With our gearing through 4th, the optimum tire diameter seems to be around the stock size, and it does make a difference in your trap speed at the end.

trey.hutcheson

iTrader: (2)

Let me know when you go to Steele. I'd like to meet up, and see what a 1.8/1.9 looks like in a z in person.

95snoozer

better gearing does not reduce mph, infact it will increase it if you are crossing closer to redline

thats a bs rule of thumb that isnt true.

lower tire pressure, i.e. bigger contact patch, i.e more rolling resistance reduces mph

12 psi on slicks CAN hurt the 2nd 1/8th mph, but depending on how much you spin on street tires going to a slick can even increase your 1/4 mph because you are putting down a higher average power throughout the race.

"Its science"

you didnt lose 3 mphg going to DRs, thats bull****

I trap the same radials, DR, slicks, I just et better on each. Its called being consistant. Slicks might hurt me by .5 mph at 12 psi

96sleeper

We need to go to Steele soon. I went once a few weeks ago and ran a new best, can't wait to run in this cooler weather.

VeeTec

I have run 1-1.5 mph slower at the same track on the same day with the same 60', not 3 mph. I was just posting the closer to 2 mph the calculator showed for the different diameter. I ran close to 103.85, and the calculator put the 26.2 at 105.8, which is close to 106, hence the "close to 106" comment.

Gearing does make a difference. I had a Maxima that would run better if you shifted early out of 3rd into 4th, where as the shift point for 1st-2nd and 2nd to 3rd was redline. That fact became a common drag strip practice among 4th gen Maxima owners. If you left in in 3rd, your trap would be lower, and you would drop out of the peak power band too long. There are a lot of factors, and it does vary between cars, but with the Z I have seen for myself what the difference is. I run 32 lbs with the DR's, and I am aware of what rolling resistance is. Consistency is not an issue with my driving either.

BTW, I would appreciate level headed discussion, this is not the street racing forum. If you disagree, that is your right, and I am always open to opinions, as long as they aren't expressed as profanities and personal attacks.

VeeTec

Whoah, 12's eh. I am falling way behind your hot rod Maxima!

I don't plan on doing one single mod, until I reach a 12.9, probably during cooler weather. I was happy that I ran 13.2 with so so track prep, so I think it will come later this fall.

Let me know when you are going a couple of weeks out, so I can plan ahead. By the time I hit a 12.9, you should be running 12.7 or so!