Upgrading transmission AND Gears

[the stallion]

Just posting this thread for anyone's thoughts and/or advice. I've been learning alot about the different gears on here, and basically I hear 4.10's are great on the stangs, but there goes your top end. I was told recently that upgrading the tranny to a "tremec" 6-speed and then installing steeper gears like 4:10's would eliminate the loss of top end. Can anybody confirm this? Does upgrading to a 6-speed and getting that extra gear take care of problems with steeper gears? Is "TREMEC" a good tranny company for a mustang? What kind of cash do you get into when upgrading to a 6-speed plus gears? Any advice would be greatly appreciated.

-Thanks
-Dan:worship:

[Tomcat427]

I have 4.10 gears going in on Tuesday. I should have enough miles on her by Sunday to open her up a little. I will update at that point.

:THUMBSUP:

[TL GT]

First off,Tremec makes the trans that is standard in all 5-speed Mustang GT's and Mach 1's.Second,swapping a 6-speed trans into your car would not be very cost effective.The trans alone would run you over $2000 not to mention a clutch and flywheel at about $400 for both.As far as losing top end with 4.10 gears is simply not true.The car will not pull fifth gear very well at top speed due to aerodynamics taking over.With a 4.10 gear you will actually get a higher top speed than with the stock gears because you will be able to rev the enging farther in fifth.Besides,I think most people would give up a little top end for way more off the line go with your way of thinking.I mean how often does anybody go over 140 MPH?

[WarpdSpazm]

You'd have to shift 4th no doubt in the 1/4. From what I've been reading you want to avoid that if possible.

What would 1st gear's ratio be in the 6-speed... Right now, aside from being on a hill or major traffic, i don't use first... it's not very driveable in terms of shifting nicely... I ride up the clutch a little slower from a dead stop in 2nd and I get a comparable start to most autos around me, and am shift free to 30mph the 2-3 shift at 3k is very nice, but i can't find any were in 1st that the nose won't dive and whiplash my G/f.

[Darkhorse]

If you stick in the 6-speed with the stock rear gears you'll actually slow the car down. The Tremec 6-speed can be had with a 2.66 or 2.97 first gear and I think their is a third choice available. First gear in the current 5speed in the GT and Mach 1 is still 3.35 I believe. The 6-speed in the Cobra has a 2.66 first gear. If you stuck in a 6-speed in the Mach 1 you would have to put in 4.30's out back just to come close to the final drive ratio you have in first gear right now. You would also need a new driveshaft. It's really not worth the trouble and the costs would exceed any advantage, if there is one, that you would get. You would get a little better highway mileage possibly. I personally think it would be a complete waste of money, no offense.

[the stallion]

Thanks all you guys for the advice. I appreciate your help. So it seems like the 6-speed wouldn't really be worth it, would in fact, possibly even slow the car down. Now with 4.10's, does that in fact throw the speedometer off by 10-20mph? How would I get them installed without throwing anything in the car off? How much more insane does accelleration become going that steep? Also, I'm new to clutches, while adjusting to the clutch in the Mach 1, would it be better for me to start out in second to avoid smoking valuable tire??

--Thanks
-Dan:THUMBSUP:

[Darkhorse]

I would practice starting out in first gear. You really should use first gear and you'll eventually get it down smoothly and you'll be wondering how you found it difficult. It's always difficult at first with the clutch when you're learning to drive a stick. Starting out in second all the time can cause a lot of clutch wear unless you have some steeper rear gears. As for your speedometer you'll need to get it corrected. They have products like Speed Cal and others. You can get a chip to correct it.

[Bullitt_#1346]

I have the T-56 in my car. Mine is the one like they used in the 2000 Cobra R with a 2.97 1st gear and a .62 6th gear. The T-56 in the 2003 Cobra, Viper, Vette, and Camaro/Firebird is a different transmission with different gearing. There are actually about 8 or 10 different versions of the T-56. Check out tremec's website for more information.

The swap cost about $3500 or so. I also have 3.73 gears in the car. I was hoping to get some driveability back, and I like having the extra gear. It isn't all that much taller than 5th in the 5 speed, but does drop the revs down a little bit. Plus now I have a whole other gear in between 4th and where 5th is in the 5 speed. It is great. I love it. Well worth the money.

[Mustang Matt]

That is one bada$$ bullitt you got there!;)
I bet you surprise alot of people with that thing.

[Bullitt_#1346]

Originally posted by Mustang Matt
That is one bada$$ bullitt you got there!;)
I bet you surprise alot of people with that thing.

It is in the process of becoming badder right now. I am getting a whole new completely built engine with p&p heads, forged rods and pistons, and a new return-style fuel system. I am shooting for around 425 - 450rwhp (on a mustang dyno).

[Darkhorse]

Originally posted by Bullitt_#1346
It is in the process of becoming badder right now. I am getting a whole new completely built engine with p&p heads, forged rods and pistons, and a new return-style fuel system. I am shooting for around 425 - 450rwhp (on a mustang dyno).


That car sounds badass. What kind of times have you been able to pull off with it in it's current configuration?

[Bullitt_#1346]

I haven't taken it to the track. The only one around here is about a two hour drive away. I would like to do it one day though.

[the stallion]

Bullit,

Just wondering, what kind of cash have you poured into your bullit? It sounds really impressive. Ideally, once my Mach 1 is paid off (5 years), I'd like to supercharge it and really boost the hp on the mach 1 motor. I'm just wondering what kind of money it would cost to get it done right, at a professional shop. Ideally I'd like hp to be over 400, supercharger, 4.10 gears(not going to affect hp but of course accelleration), maybe even some NOS? Any advice?

-Thanks
-Dan:!!:

[Bullitt_#1346]

Here are all the mods with approximate prices. I don't have the invoices in front of me, but this is what it cost approximately.

supercharger - $3800
s/c installation & custom dyno tune - $1400
Autometer Gauges - $350
Custom Bullitt shift knob from MGW - $60
Window Tint - $120
3.73 gears - $175
gear install & fluids - $300 (speedo corrected by chip, no charge)
Green Stuff brake front brake pads & install - $200
Cobra R Wheels - $1200 (used on Ebay)
AFM powerpipe - $200
Pro-M MAF - $450
New Dyno Tune - $650 (took another whole day)
Install on MAF, Catback, and Gauges- $500
Eibach Sportsline springs & install - $500
Magnaflow Magnapack Catbacks - $440
Magnaflow X-pipe & Install - $500
T-56, fluids, labor, etc. - $3300
Custom driveshaft - $375
Steeda Tri-Ax - $180

[Darkhorse]

Originally posted by the stallion
Bullit,

Just wondering, what kind of cash have you poured into your bullit? It sounds really impressive. Ideally, once my Mach 1 is paid off (5 years), I'd like to supercharge it and really boost the hp on the mach 1 motor. I'm just wondering what kind of money it would cost to get it done right, at a professional shop. Ideally I'd like hp to be over 400, supercharger, 4.10 gears(not going to affect hp but of course accelleration), maybe even some NOS? Any advice?

-Thanks
-Dan:!!:

Considering what your future plans are in terms of supercharging and/or NOS, you would need a custom built shortblock with stronger rods and forged pistons with a lower compression ratio for starters. In a supercharged application I would stay with a 3.73 ratio and no more. 4.10 would be better in a N/A car. The contents of the 03 Cobra shortblock would do well also. The Mach's motor as it stands now will not last long with a supercharger. 10.1:1 compression with the hypereutectic pistons along with some of the stock 4.6 rod and piston weaknesses don't make for a safe motor to supercharge unless you had a lower c/r.

[Bullitt_#1346]

This is true. The 2V engine in the Bullitt has a lower compression ratio than the Mach does. The 4V engines have always taken well to boost over the years in the Cobras, however. I am sure that within a year Vortech will come out with a kit designed for the higher compression engines in the Mach that will be safe without getting forged internals. Chances are the boost will be limited to around 7lbs or so. When I say safe, I mean it shouldn't burn up your pistons or anything like that, as long as you got a safe dyno tune. Never trust the out of the box tunes that come with superchargers. Spend the extra money to get it done right. As with any engine, the harder you drive the car the faster it is going to wear out the engine.

[Darkhorse]

It's been my experience that even a low boost system on stock pistons and rods with the Mach's c/r is not a good thing. I wouldn't trust even 7 pounds myself. The past Cobras have slightly lower compression ratios and if you go over to sites like blueovalnews.com or corral.net you'll find plenty of Cobra guys who had to rebuild shortblocks after some time with a supercharger. But, to each his own. That's what is great about the car hobby. Everyone can try their own thing and see how it goes and can pass along their experiences to help everyone else starting out. It's about personalizing your car and doing what you want with it.:cool:

[Tomcat427]

Hey guys,

Had the 4.10's installed Tuesday. At the same time I had them put in Red Line gear oil in the trans and axle. (What a differance it made in the shifting.) I also have the FRPP aluminum drive shaft installed.

70mph is at 2250 rpm's (Speed I am traveling at the most)

I also had the MAC cat-back exhaust (Dallas Mustang part #6693) installed. It sounds really good!! Parked next to a Cobra this afternoon and my new 3 1/2' pipes (after the rear axle) looked awesome next to his.

I have not gotten on it yet. I am waiting until I have at least 500 miles on the new gears.

Saving now for BBK Long Tubes and still deciding on the X or H pipe.

[Mustang Matt]

Originally posted by Tomcat427
At the same time I had them put in Red Line gear oil in the trans and axle. (What a differance it made in the shifting.)
Yes! somebody has finially taken my advice!
Good to hear you got good results
:)

[Darkhorse]

Originally posted by Tomcat427
Hey guys,

Had the 4.10's installed Tuesday. At the same time I had them put in Red Line gear oil in the trans and axle. (What a differance it made in the shifting.) I also have the FRPP aluminum drive shaft installed.

70mph is at 2250 rpm's (Speed I am traveling at the most)

I also had the MAC cat-back exhaust (Dallas Mustang part #6693) installed. It sounds really good!! Parked next to a Cobra this afternoon and my new 3 1/2' pipes (after the rear axle) looked awesome next to his.

I have not gotten on it yet. I am waiting until I have at least 500 miles on the new gears.

Saving now for BBK Long Tubes and still deciding on the X or H pipe.

Sounds great! Keep everyone posted :)

[Tomcat427]

Once I get the 500 miles on the new gears I will have another dyno.:THUMBSUP:

Right now everything seems to fit in with my driving habits really nicely.

may have to let the wife puton the last 200 miles. Getting really anxiuos(sp) to open it up!!
:HOPPY: