[Smoothgrandmama]

I like how you said ''close to 120'' without giving an actual speed.

And the last info i have was not for the op. It was for the fella who wanted to do over 120.

Also traction with boosted isnt just about where your making the power. If you have a 420 hp centri car you will still be making over 320 hp @4000 rpms now think about power shifting 2nd at full boost with 4.10s your going to need one hell of a tire with some decent suspension to keep from breaking loose.

 

[RALVAREZ26]

I like how you said ''close to 120'' without giving an actual speed.

And the last info i have was not for the op. It was for the fella who wanted to do over 120.

Also traction with boosted isnt just about where your making the power. If you have a 420 hp centri car you will still be making over 320 hp @4000 rpms now think about power shifting 2nd at full boost with 4.10s your going to need one hell of a tire with some decent suspension to keep from breaking loose.

oh, well i cant give you the actual speed since i was focusing more on the road than trying to see the exact speed on the odometer.

regardless if it's 4:10's or 3:73's you still need to be able to put the power to the ground, i agree with you there.

 

[Smoothgrandmama]

You tell me you the tire your running and what your rev limiter is rev at and ill tell you how fast you were going

 

[dcook_14]

everyone that i know that is making some nice numbers drive w/ drag radials on, shoot even me w/ just under 250rwhp have drag radials. what's the point of being boosted and riding around in street tires, regardless if you have stock gears or 3:73's or 4:10's you're going to spin your ass off

the point in being boosted and riding around on street tires is because I drive almost 50 miles a day just to and from work plus anywhere else I want to go. Figure 400 miles a week. I'd go through DRs pretty quickly, and I don't feel like spending $350 every 7 or 8 months. I have no problems with street traction in my boosted mustang, stock suspension, shitty tires because I don't drive like a jackass on the street. I'm rarely over 2500 rpm, there's no need to drive fast and tear around on the street. Leave that stuff for the track.

Also traction with boosted isnt just about where your making the power. If you have a 420 hp centri car you will still be making over 320 hp @4000 rpms now think about power shifting 2nd at full boost with 4.10s your going to need one hell of a tire with some decent suspension to keep from breaking loose.

I'm curious to know where you got 320hp @ 4000. Is that from a dyno sheet?

What do you consider one hell of a tire. If I was serious about weekend dragging my car I'd get some spare rims and MT ET streets or go with an actual slick.

 

[Eagle2000GT]

4:10's does not equal only for track, my car is a daily driver and have over 150K miles on it. granted, once i get another car as a daily i'm going bigger w/ my gears (4:56's) also, i have 2 buddies with boosted mach's and both have 4:10's
one is a 380rwhp auto mach1 with an eaton
the other is a 460rwhp procharged mach1 5spd
and their both daily drivers also.

You're not boosted and Mach I's tach higher than our motors. That makes a difference. Tire size also makes a difference. Anyone running 18" wheels? How about 28" slicks?

It has always seemed to me that the 4.10 mafia never looks at application. They just always recommend 4.10s. I have read numerous posts from guys who have taken their 4.10s out for higher gears. Lack of traction on the street is the primary reason.

 

[Eagle2000GT]

Edit: Oops. Somehow I posted a draft then reposted the final version saying the same thing.

 

[Eagle2000GT]

Hmm... I guess I can see that, but I'm curious to know how well this thinking applies to centri blowers. PD blowers, yeah I can see traction problems with 4.10s. Centri blowers don't make decent boost and hp until higher in the rpms, so you should already be rolling at a decent speed before you're making big power. If you're breaking the tires loose after they are already rolling at 15-20 mph, you should probably look into DR or other tires with some more grip haha

I'm running street tires with 3.73 gears and a centrifical supercharger. I cannot kick it down at 20 mph in first without spinning the tires and hitting redline. I have to feather the throttle shifting to second or else it does the same thing. I don't intend to run DRs because I drive 500 miles per week in all sorts of weather. But I do need a better tire than the 315/35 Sumitomo's that came on the wheels.

I read a thread once started by a guy running around 475 rwhp with 4.10 gears on his centrifical supercharged daily driver. Apparent his car went sideways almost every time he went around a corner or passed a car. I think the car scared him a little but he didn't have the money to get higher gears. Traction can be a issue even with centrifical superchargers.

I have read a lot of posts from people who have taken out 4.10s for a higher gear. Most were from guys driving supercharged cars but even NA guys who did not like how short first gear became have taken them out. (I read a post from a 4.10 advocate who actually recommended taking off in second instead of first to overcome this problem. Why anyone would intentionally put in a gear that caused them to do that is beyond my comprehension.)

You can overcome some of the drawbacks of lower gears by putting on taller tires. For example switching from 245/45-17s to 255/50-17s will make 3.73s more like 3.55s and 4.10s more like 3.90s. 245/45-18s do the same thing. 19" and 20" wheels really tame down the gears.

 

[RALVAREZ26]

You tell me you the tire your running and what your rev limiter is rev at and ill tell you how fast you were going

i have 275/40/17 and rev limiter is set a 6k

You're not boosted and Mach I's tach higher than our motors. That makes a difference. Tire size also makes a difference. Anyone running 18" wheels? How about 28" slicks?

It has always seemed to me that the 4.10 mafia never looks at application. They just always recommend 4.10s. I have read numerous posts from guys who have taken their 4.10s out for higher gears. Lack of traction on the street is the primary reason.

auto mach1 use to ride on 18x10 deep dish bullets but went to driving around in his stock 17 because he had his MT's on those.
the procharged mach is riding around 18x9 saleens

 

[Smoothgrandmama]

i have 275/40/17 and rev limiter is set a 6k

That tire is the same size as the stock tire. With 4.10s and 3650 trans at 6000rpms you were doing 108.4

Im thinking you glanced at it and thought it was 118 is that possible?

 

[competition orange]

If your staying NA, go with 4.10's. They are sick on the GT's. The top of 4th gear with 4.10's is 111mph on the stock tire.

Your gas mileage should be pretty good, because it's less pedal effort, and if your doing like 40+mph you can put it in 5th.

If you have some good tires that grip good, you wont wheel spin to bad. Espcially if you do control arms.

+1:yes

 

[RALVAREZ26]

That tire is the same size as the stock tire. With 4.10s and 3650 trans at 6000rpms you were doing 108.4

Im thinking you glanced at it and thought it was 118 is that possible?

i doubt it but i could be wrong. one day i'll double check.

 

[Smoothgrandmama]

Also if you have a t45 trans its the same speed

 

[RALVAREZ26]

Also if you have a t45 trans its the same speed

oh, you could be right but when i checked it was when i raced this guy on the first video, we went from a 50-120 roll:
http://www.moddedmustangs.com/forums/street-101/137873-sat-night-races-videos.html

 

[huggy bear]

Very interesting thread! Its a little bit different than most gear threads! Good info!

 

[Smoothgrandmama]

oh, you could be right but when i checked it was when i raced this guy on the first video, we went from a 50-120 roll:
http://www.moddedmustangs.com/forums/street-101/137873-sat-night-races-videos.html

The doesn't really help me lol.

Something to remember is that speedo's become more innacurate at higher speeds. a gps is more accurate, but I doubt your speedo would be off 10 mph though

Something to keep in mind is that if your tires were worn than that also affects your speedo ever so slightly that 5/32ndth of an inch can throw you a few mph too

 

[RALVAREZ26]

The doesn't really help me lol.

Something to remember is that speedo's become more innacurate at higher speeds. a gps is more accurate, but I doubt your speedo would be off 10 mph though

Something to keep in mind is that if your tires were worn than that also affects your speedo ever so slightly that 5/32ndth of an inch can throw you a few mph too

i didnt know about the tire stuff, very interesting. i'm very curious to know now, so i'll be checking soon.

 

[CW5billwade]

I did a lot of research and went with the 4.10s but I am auto. search my user name. Summit still had the FRPP 4.10s when I bought mine but that was 6 months ago. Look for the A in the part number. Also they will price match. Went with Summit because they were the only one that had the FRPP rebuild kit. If you have high mileage get the rebuild kit and hve them price match late model restroration on the gears. After install they were and are quiet as a mouse use Amsoil gear lub with friction modifyer.