So as a lot of you know I upgraded to 4.08s last weekend and this weekend I finally opened her up. She feels faster... Throws you back in your seat more than before. But it didn't feel like it was as big of a difference as I thought it would be... Well, every time I do a new mod I race my friend to see how much a difference it made. He didn't change anything on his car, and before I beat him by 3 car lengths... Now, I barely beat him by one, and idk what gives... I'm 100% sure he didn't add any extra mods to his car. The only difference is his tires are starting to get a little bald so we went from a 20 roll instead of a dig. But he normally jumps me by half a car to 3/4s of a car from a stop anyway so I figured a roll would be better for me. I started in 1st gear at around 4k rpms. My tires are near full tread Toyo T1Rs, psi is 42 on the front tires and 38 on the rears... Rpms in 6th gear sit at exactly 3k when driving 70mph. So I think they did put in the 4.08s and not other gears by mistake... No lights on the dash, no funny noises, just changed the oil 100 miles ago... I'm out if ideas... The only thing I can think of is I didn't turn of TC.... But usually I don't. But I'm thinking maybe with the different gears TC can effectively pull more power and slow the car down maybe? Or something?

Idk, I'm dumbfounded.

 

Use an objective criteria to track improvements, not how man car lengths you beat your buddy by. Maybe you sucked that day. Maybe he got better. A 0-60 or quarter mile time will show that your acceleration is faster now than before. As do the laws of physics.

And stop street racing like an idiot and take it to a track.

 

I'd love to take it to a track, closet is 2.5 hours away and between school and work I don't have a lot of time to go out there. I will eventually. I understand racing someone had it's variables but 3-4 lengths consistently down to 1/2-1 length consistently there's something wrong there...

I appreciate your concern and it's well placed. However my buddy I race owns a metric **** ton of land that's enclosed by a stone wall with a coded gate, on it there's a stretch of straight concrete road that we have fun on from time to time. Not saying I've never street raced, or that I'm high and mighty, above it etc... But no innocent motorists were put in danger in the making of this film

 

TC. untuned. Tire spin. Granny shifting.

 

Sway
You sacrifice a little top end speed for being a bit quicker...shifts between gears will also
Come quicker as well .... 1/4 mile times will be better. But top end speed over all will be a bit compromised. Just my 2 cents worth ��

 

I'm comparing to where I was before, not tuned before, shifting was the same...
We ran from 20 to maaaybe 100... Maybe 80 or 90. I just figured I'd get there a lot quicker than before... Not slower... TC is the only thing I can think of.

 

I can't help with your concerns, but holy crap 42 psi?

 

If I may ask, why specifically 42 psi in the front and 38 psi in the rear? Does this improve anything?

 

35 psi is my max all around.

 

That PSI is way too high man, try 34 front and 32 rear next time.

 

I normally do 37 front 32 rear, but I just got it serviced and they air up the tires when they change the oil.... I just hadn't let air back out yet. I guess they just added 5psi per tire.

Rouge - higher psi for better gas mileage, lower psi for better traction. (Within reason)

 

A couple things that I have noticed that make my car much slower.

1st is the heat. I know every vehicle suffers performance wise with the heat. But I have noticed that this is huge factor for the G37. This high revving 3.7 liter is already generating a lot of heat as is. Add in the summer temps and the performance of the G suffers a good deal. In my opinion it is a night and day difference. Living here in Las Vegas I feel sorry for my car during the summer.

The 2nd thing that has seemingly had an affect on my performance is my gas. I stopped using Chevron gas a few months back because the car felt sluggish. I don't know if it is the Techron summer blend or what. But I stopped using it and switched to Shell V-Power.

 

I've seen other posts stating 29psi in the rear. GL. I'll be going to Chatsworth soon so figure it out fast, lol!

 

I see, so I'm guessing a good midway point for our cars is somewhere around the 30's then? Maybe 35psi?

 

The car says 35psi on the door jam, the tires say max 50. 35 is safe a bet.


Will- true it is about 15 degrees hotter here right now, TX isn't exactly the coldest state lol. And thanks about the gas tip, I isually use Exxon, I'll try shell vpower next and see how she likes that.