4.10s went in today!

99VERT

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Well i'm hooked! Initially I went from 3.31s to 3.55s and there was a slight increase in fun factor. Today my buddy, who runs a Ford service department, swapped keys with me and took my car in for the 4.10 gear swap. I had the pleasure of driving his Boss 302 while he did the gears which was a nice treat. His High winding 5.0 with full exhaust, JLT intake and a tune. My buddy calls me when he got to work to tell me how he screwed up not getting the shelby! He is hooked on that 5.8 torque monster! I have to say i was a little disappointed in the Boss down low but once you hit the 4000 rpm mark it comes alive. Back to the gear swap. They finished it in a day and its close to being quiet as the stocker. We will see if that lasts long term or not. The drivability is absolutely perfect for me! Growing up with fox body mustangs with t-5s or TKOs and 3.73 rear gears I'm used to shifting a lot. The long gear set in the Shelby is masked by the brute power these cars make so I found myself enjoying 1st and second gear then popping it up in 3rd gear nearing 100 mph no problems. The 4.10 swap feels like a properly geared car now that has enough snap that the car can be quick even off the boost. I went back and forth on this months ago and Biminilx said go 4.10s and I chose the route of 3.55s because I had a new set on the shelf. I wish I had just gone to 4.10s from the start. It sounds like a lot of gear but with our transmissions gearing it really isn't. The gearing feels equivalent to a Fox body with 3.55s and vortech supercharger minus all the rattles of course plus you have 6th gear to boot! I actually used 6th gear on the highway today and cruised 80mph at 2000rpm. If your on the fence about this go for the 4.10s!
 

Softballer77

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I went 4.10s and haven't looked back. Makes the car pretty viscious to me, and I got 22mpg modded and with those gears from Kentucky to Michigan back in the spring. Mine began to whine though after a few DR launches at the track.

Have fun with them!
 

heatsoaked12

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I have a 12 with the 2.66 first, aluminum flywheel, 3.73 and over 100 less hp than the 13/14. It really feels like I have to rev the car too much too get it moving. I was also thinking of the 4.10s but didn't want to over rev at the end of the quarter with the 12 having a rev limiter of 6250 rpm. I figured once I pulley (or TVS)it Id want the 3.73s back. any thoughts? thanks for posting your 4.10 opinions.
 
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Softballer77

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I have a 12 with the 2.66 first, aluminum flywheel, 3.73 and over 100 less hp than the 13/14. It really feels like I have to rev the car too much too get it moving. I was also thinking of the 4.10s but didn't want to over rev at the end of the quarter with the 12 having a rev limiter of 6250 rpm. I figured once I pulley (or TVS)it Id want the 3.73s back. any thoughts? thanks for posting your 4.10 opinions.

Mine comes close to redlining 7k in 4th going through the traps with 4.10s and a 27.9" DR at around 134. Your 4th gear is 1:1 as ours, so should be the same. I'd stick with 3:73s if you plan on adding power and don't want to go over 6250rpm through the traps. If you take my same scenario above with 27.9"DR going through the traps at 134, your 3.73s would be around 6019rpm.

If you had a 29" DR with same scenario, you would be closer to 5800 rpm.
 

biminiLX

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Love my 4.10's...Run a 29" DR tire with some BMR goodies back there and it's heaven.
This.

OP--- glad you're happy, I usually don't get as vocal about a mod as I've been with gears, specifically 4.10s with this car if you run a taller DR.
To me it's perfection and I couldn't get the 3.31s out soon enough to.
-J
:burnout:
 

heatsoaked12

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Mine comes close to redlining 7k in 4th going through the traps with 4.10s and a 27.9" DR at around 134. Your 4th gear is 1:1 as ours, so should be the same. I'd stick with 3:73s if you plan on adding power and don't want to go over 6250rpm through the traps. If you take my same scenario above with 27.9"DR going through the traps at 134, your 3.73s would be around 6019rpm.

If you had a 29" DR with same scenario, you would be closer to 5800 rpm.

Thanks for doing all the the calculations! I may go 4:10s for the street and put a 29" dr for track days. The 4:10s will pretty much bring my first gear back to factory specs. I also may make adjustments to my red line the slightest bit to make sure I don't have to shift into 5th.
 
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