3.55 or 3.73

[OxMox]

Ok, I need some help with this. I got a '04 Mach and I want to do gears... BUT, I don't want 4.10's. I had 4.10's on my V6 and they were cool & fun and all that, but a little too much work. Maybe they sucked cause they were on a 6, but I still would rather get something a little smaller. I was thinking of 3.55 or 3.73 but I don't want to lose to much of the bottom end torque.

This is some of the modds I plan on doing (to help you guys out a little)

Camms
Headers LT's or Mid-length (already have o/r x-pipe & cat-back)
Intake
90mm MAF
T-body
Pulleys
Ported heads
...Pretty much keeping it N/A

I'm stuck with 3.55's but any help on decideing would be appreciated

 

[BennyBlown2v]

Your Mach already has 3.55's.

 

[hotrodnut]

The Mach1 has 3.55's from the factory. I would not go more than 3.73's without upgrading to 31 spline axles and posi because the torque mutiplcation goes up too much with any more gear than that.

I can tell you with the 3.73's over the 3.55's in my Mach1 it pulls a lot stronger up top in 3rd and 4th. I've had 4.30's without the upgraded 31 spline parts and then 4.56's with all good stuff but for me I'm really happy with the 3.73's overall.

 

[RandyStinchcomb]

if your a serious racer, 4.30's or 4.56's at best on a N/A DOHC, if your going wth a power adder later on then I'd do 3.73's. remember this is a high-reving 4V not a V6, "don't fear the gear"

 

[OxMox]

I didn't know the Mach had 3.55's stock. I thought it was 3.20 somthing...

Ok, then how does everyone feel about the 3.73's? And how would they mix up with an Auburn Ected differential?

 

[helty]

since you already have 3.55s i dont thinkg 3.73s would be a big step up in preformance. on a 2V 3.73s are a nice step up, but with the mach i would go 3.90s at least. (4.10s, 4.10s....smile)

dont fear the gear man.

 

[OxMox]

since you already have 3.55s i dont thinkg 3.73s would be a big step up in preformance. on a 2V 3.73s are a nice step up, but with the mach i would go 3.90s at least. (4.10s, 4.10s....smile)

dont fear the gear man.

When I had the 4.10's on the V6 I had a better start off the line, but I had no top end and very little mid-range power! It felt like it killed everything, so that's what i'm worried about... I don't want to put them in the mach and loose everything up top and have very little mid-range to work with

 

[tomustang]

I didn't know the Mach had 3.55's stock. I thought it was 3.20 somthing...

Ok, then how does everyone feel about the 3.73's? And how would they mix up with an Auburn Ected differential?

You have an extra 1000RPMS over a GT, those 4:10's on a 4V will act like 3:73's in a GT.

Get the 4:10's

 

[RandyStinchcomb]

When I had the 4.10's on the V6 I had a better start off the line, but I had no top end and very little mid-range power! It felt like it killed everything, so that's what i'm worried about... I don't want to put them in the mach and loose everything up top and have very little mid-range to work with

your not going to loose and mid-range and anything up-top wth a DOHC

 

[OxMox]

your not going to loose and mid-range and anything up-top wth a DOHC

Ok, I was just wondering. Cause if it won't make any difference than just giving me better launch off the line than I might not bother. The 4.10's didn't do anything from a roll, and very little when I was in traffic and it felt slower than before I installed them. I don't want to get them if all there going to do is rev my engine and not get me anywhere quicker... I'll look into them and see how other people with them on a 4v like'em and see if it actually made a difference

 

[tomustang]

Ok, I was just wondering. Cause if it won't make any difference than just giving me better launch off the line than I might not bother. The 4.10's didn't do anything from a roll, and very little when I was in traffic and it felt slower than before I installed them. I don't want to get them if all there going to do is rev my engine and not get me anywhere quicker... I'll look into them and see how other people with them on a 4v like'em and see if it actually made a difference

4.10's will make you **** a brick compared to when you had a set in the v6

 

[tradde]

Go with the 4.10s. You will not regret it.

 

[todd4566]

If your going to spend the money on a gear change, go with at least 4.10, but on a 5spd I'd even push 4.30 on the 32v. Going with something like 3.73 is a waste, unless the labor is free or your getting a ridiculous deal.

The Mach1 has 3.55's from the factory. I would not go more than 3.73's without upgrading to 31 spline axles and posi because the torque mutiplcation goes up too much with any more gear than that.

Sure it's great to upgrade to 31 splines, but it's not madatory. There are numerous people over on the Mach 1 Registry who have switched to 4.30 & are still running an otherwise factory rear-end with no issues.

 

[OxMox]

If your going to spend the money on a gear change, go with at least 4.10, but on a 5spd I'd even push 4.30 on the 32v. Going with something like 3.73 is a waste, unless the labor is free or your getting a ridiculous deal.



Sure it's great to upgrade to 31 splines, but it's not madatory. There are numerous people over on the Mach 1 Registry who have switched to 4.30 & are still running an otherwise factory rear-end with no issues.

I asked one of my friends who has 4.10's on a cobra and he likes them alot... says it spends less time reving up to get into the power band than before and he says if he lost any power he can't really tell.

What's the difference in the 31 spline than the 28?

 

[todd4566]

What's the difference in the 31 spline than the 28?

Strength of the rear axles. The more power & gear you added to your car, the more abuse the splines take. Your very unlikely to have any issues on street tires, but if you decide to slap on drag radials, that's when the real carnage begins.

 

[streetstang03]

niether.

4.10s or 4.30s. you wont feel much of a difference w/ 3.73s.

 

[Give Me TP]

I am using 4.10s in my daily driver '03 Mach 1 and have absolutely no regrets.

 

[BLUE03GT]

no brainer.... Motive 3.90's

 

[Jackie Chan]

no brainer.... Motive 3.90's

have you driven a car with 3.55, 3.73, 4.30s and so on? if not please dont tell him that is the best gear. escpecially since he is in a 4v

i would personally go 4.30 without hesitation if I just planned on street use....if i was going to race with any frequency 4.56's and slicks

if you dont want any reall gears in there, i have no idea why you would even bother with headers or ported heads

 

[03ghoststang]

4.10's DONT FEAR THE GEAR!!!!!