should I switch from 3:55 to 3:73 gears with new mods??

[1993whtstang]

My mechanic just installed new 3:55 gears with all new bearings and a new traction lock housing about 5 months ago. I also installed a new ford racing cradle rear end cover.

I am going to be installing a trick flow top end kit with headers, 75mm throttle body, new MAF, 24 lb injectors, 255 lph fuel pump,etc. Should I put a set of 3:73 gears in or just keep the 3:55's in?? Would I motice a big difference between the two?? I only am going to be using this to street cruise and maybe the track once or twice a year for an amature run. I hate to pay to have the gears swapped out again, but if it will make a huge difference I could be convinced!

Any info is appreciated!

 

[NIKwoaC]

There is really only about a 5% difference between the two sets of gears, so considering you just had the 3.55s installed, I would put money elsewhere. I think bang-for-the-buck, you'd be wasting money, especially if you're paying someone to do it.

 

[fiveohwblow]

There is really only about a 5% difference between the two sets of gears, so considering you just had the 3.55s installed, I would put money elsewhere. I think bang-for-the-buck, you'd be wasting money, especially if you're paying someone to do it.

I second this. Most people will say things like "dont fear the gear" etc etc but this comes from a pure drag racing and stickier than reasonable tire perspective. Save your money and stick with the 3.55's.

 

[1993whtstang]

thats what I was hoping, I was just concerned about over reving, thanks for the opinions guys!

 

[NIKwoaC]

Yea, I mean I don't know how much your mechanic charges to install gears, but I would guess parts+labor would be around a grand. That's more than halfway into a supercharger or a stroker kit, both of which would be way better payoff than going from 3.55s to 3.73s.

Don't get me wrong, I'd normally support 3.73s, but I think in your case you're better off spending elsewhere.

 

[mob]

/thread

 

[Gearbanger 101]

thats what I was hoping, I was just concerned about over reving, thanks for the opinions guys!

You would rev higher with 3.73's, than you would with 3.55's, not lower.

The lower numerically gear ratio's in a street car are to get your car up and moving more quickly. The stock 225hp our cars came with wasn't bad for it's time, but additional gear multiplication is necessary to really get these cars moving from a standstill.

With the mods you're suggesting in your sig, you're effectivley adding about 130hp to the stock output. You'll now pull the 3.55's much harder than you would have back when the engine was stock. Keeping the engine within the sweet spot of it's powerband is more important than maximizing mechanical gearing efficency.

As stated by the others.....the 3.55's are probably the right choice.

 

[Mark Palmer]

Good thread, I always like them.

 

[jdb3rd]

Not worth the money to swap at this point especially if you enjoy cruising the streets as well with the car. You didnt mention whether or not you had brake or suspension upgrades but I would definitely address the brakes before another gear change.

 

[1993whtstang]

Not worth the money to swap at this point especially if you enjoy cruising the streets as well with the car. You didnt mention whether or not you had brake or suspension upgrades but I would definitely address the brakes before another gear change.

Thanks again for the information guys. I do have new front SSBC front slotted rotors , new stock calipers, SSBC brake pads, stainless brake lines, new fluid reservoir, all new front bearings etc. The rears are still drum type, but are brand new. I was new to the fox mustang when I had those done and wasnt aware of the rear disc conversion kits they had. Suspension is all new shocks,new struts,new rear quad shocks, and new eidelbach ront and rear sway bars.

 

[jdb3rd]

Nice man how about subframe connectors

 

[1993whtstang]

Nice man how about subframe connectors

Yep, welded subframe connectors and front strut tower brace. She is coming together nicely! Ill post some final pics and dyno numbers hopefully within the month.