Don't Fear 4.10's
02-23-2007, 12:30 PM
#1
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Thread Starter
Join Date: May 2005
Location: South Carolina
Posts: 8,191
Don't Fear 4.10's
To recap, I bought a set of gears and a t-lock from (John) Lund Racingfor my 7.5" rear. I had originally planned to install them in my vert, but I gave that car to Mrs28HopUp and bought a used TG 2006 4.0L/5spd coupe. Although it had looked at one point like I might need tosell the coupe cuz my wife might lose her job, that is no longer the case (YEAH!). Regardless, I decided to keep the car and build it up, so I had Evolution Performance install the gears/LSD I bought from John (who works with Evol from time to time).
Well, it turns out that the gears were not the 3.73's that I thought I purchased, they were 4.10's. And on top of that, Evol said the t-lock (which I knew had been rebuilt with an extra clutch pack) was not operating as it should once installed. It was acting like a locker rear-end, which would be fine on a dedicated track car, but not on a daily driver. It looked as though I would be having a Detroit Tru-Track installed, but Fred said that Nelson (who does their gear installs) was able to free up the LSD without taking it apart (apparently it needed to break-in). Although I hadn't planned on going with 4.10s, the car was fully assembled, and I figured I'd keep them and run a taller rear tire. So I picked up the car last night, and now have about 120 miles on it since the install (so I still haven't "tested" the LSD - I'm being patient for another 100 miles or so).
All I can say is that I am very happy with the 4.10's. There is a whine, but nothing unacceptable. RPM-wise, I do notice the change. My main concern was the RPM that I would see in 4th gear going through the traps at the track with my current tires (27" dia Pirelli's). I wound it out in 4th gear to 95 mph, and I was under 5K RPM. That is perfect for me. The only time I would be going above 75mph would be at the track, so the 4.10's are great for my needs. I plan to run 28" dia drag radials, much like scrming was running prior to swapping in 3.73's. Can't wait to test the LSD!
Other changes to the car were non-adjustable billet LCA's made by Evolution (which they have on their 9-sec GT500 - they look sick!), a BMR adjustable UCA and bracket, and a PowerHouse 1-piece driveshaft and safety loop (which with 4.10's I'm glad I changed the driveshaft). I had already installed the C&L intake and 93 tune, along with the GT take-off muffler. This car pulls hard now. Next up is dual GT mufflers with Ford mid-pipe and X-pipe, and maybe a few other little things.
Sorry for being long-winded, but I wanted to pass along my initial impressions of the 4.10's in case anyone was still considering gear choice.
Well, it turns out that the gears were not the 3.73's that I thought I purchased, they were 4.10's. And on top of that, Evol said the t-lock (which I knew had been rebuilt with an extra clutch pack) was not operating as it should once installed. It was acting like a locker rear-end, which would be fine on a dedicated track car, but not on a daily driver. It looked as though I would be having a Detroit Tru-Track installed, but Fred said that Nelson (who does their gear installs) was able to free up the LSD without taking it apart (apparently it needed to break-in). Although I hadn't planned on going with 4.10s, the car was fully assembled, and I figured I'd keep them and run a taller rear tire. So I picked up the car last night, and now have about 120 miles on it since the install (so I still haven't "tested" the LSD - I'm being patient for another 100 miles or so).
All I can say is that I am very happy with the 4.10's. There is a whine, but nothing unacceptable. RPM-wise, I do notice the change. My main concern was the RPM that I would see in 4th gear going through the traps at the track with my current tires (27" dia Pirelli's). I wound it out in 4th gear to 95 mph, and I was under 5K RPM. That is perfect for me. The only time I would be going above 75mph would be at the track, so the 4.10's are great for my needs. I plan to run 28" dia drag radials, much like scrming was running prior to swapping in 3.73's. Can't wait to test the LSD!
Other changes to the car were non-adjustable billet LCA's made by Evolution (which they have on their 9-sec GT500 - they look sick!), a BMR adjustable UCA and bracket, and a PowerHouse 1-piece driveshaft and safety loop (which with 4.10's I'm glad I changed the driveshaft). I had already installed the C&L intake and 93 tune, along with the GT take-off muffler. This car pulls hard now. Next up is dual GT mufflers with Ford mid-pipe and X-pipe, and maybe a few other little things.
Sorry for being long-winded, but I wanted to pass along my initial impressions of the 4.10's in case anyone was still considering gear choice.
02-23-2007, 01:14 PM
#2
6th Gear Member
Join Date: Jul 2005
Posts: 5,172
RE: Don't Fear 4.10's
Thats right on, people should not fear 4.10's IMO, especially on a all out bolt on NA car. Gears and LSD are one of my favorite mods to these cars. It really puts a lot more "fun factor" into driving them.
Congrats.
Congrats.
02-23-2007, 01:53 PM
#4
Join Date: Dec 2006
Posts: 15
RE: Don't Fear 4.10's
i also just put in 4.10s and tlock. There is a little whine at 40mph but not bad at all.
comfortable at 70mph-2550rpms-24.5mpg
but over 70 it starts eating gas and feels rougher
I think duals are next and maybe longtube header
comfortable at 70mph-2550rpms-24.5mpg
but over 70 it starts eating gas and feels rougher
I think duals are next and maybe longtube header
02-23-2007, 03:28 PM
#5
3rd Gear Member
Join Date: Jun 2006
Location: michigan
Posts: 674
RE: Don't Fear 4.10's
Thanks for posting that, I plan on switching to 4:10's after I hit the track this year. I want to get some good runs in to compare to my current 3:73's. I was concerned that the 4:10's would raise the RPM's too much for the highway driving I do, but it sounds like they are ok at 70 mph it seems. I also use the 28" M&H dr, it takes a lot of spinning to warm them up, that can only be helped with the 4:10's.
02-23-2007, 03:36 PM
#6
Join Date: Dec 2006
Posts: 15
RE: Don't Fear 4.10's
i go 50miles round trip 4 days a week and was worried but it is just fine. There is very little noise
at 70 . Boss I have a auto, c&L cai ,single gt takeoff muffler and the 4.10s. I am thinking about headers and duals.
Did they add a lot to your car. I have not been to the track but getting close to 14.5 would be great. Any feed would be apreciated.
193rwhp
at 70 . Boss I have a auto, c&L cai ,single gt takeoff muffler and the 4.10s. I am thinking about headers and duals.
Did they add a lot to your car. I have not been to the track but getting close to 14.5 would be great. Any feed would be apreciated.
193rwhp
02-23-2007, 03:53 PM
#7
Join Date: Dec 2006
Posts: 15
RE: Don't Fear 4.10's
the reason I dont cruise at 80 is because I start to feel vibrations that are from the drive shaft.
the guys at azdyno said that might happen and the best solution is aluminum drive shaft.
so you can probably go 80 with ease if you can aford the gas
the guys at azdyno said that might happen and the best solution is aluminum drive shaft.
so you can probably go 80 with ease if you can aford the gas
04-14-2007, 01:07 AM
#10
MF Administrator
Thread Starter
Join Date: May 2005
Location: South Carolina
Posts: 8,191
RE: Don't Fear 4.10's
After almost 2 months with the 4.10's, I must say that I am VERY pleased with the change. Gas mileage has not gone down much (<1mpg). The car is much more responsive now. There is a slight whine, but nothing objectionable. Some sound deadening material will help I'm sure, but I want to lighten the car first for the lowest ET's before I add sound deadener.