Pros and cons of swapping from a 60e to a 400

**shadowbandit** · 02-07-2018, 05:51 PM

so im really thinking about swaping over my car from a cpt pro race built 60e to a cpt 400 with a brake but i need some. pros and cons from everyone so it can make my choice a little easier.
set up
350
H/C
DANA 60 -4.10 GEAR
STALL AS IS RIGHT NOW 3600-3800
NITROUS CAR ON A PROGRESSIVE 125 SHOT
26" TIRE

**AL 9C1** · 02-07-2018, 06:09 PM

Well the brake is definitely a plus. Other than that, you lose overdrive. Unless the 400 has better gear ratios for your application.

**Injuneer** · 02-07-2018, 08:16 PM

Upside - TH400 can be built for more power (but Cahall can build a killer 60E), easy to run a brake and a manual valve body.

Downside - heavy, larger drivetrain losses (saw over 20% drivetrain loss at 750 HP with a non-locking converter). And as mentioned above, no O/D (unless you add a heavy, expensive Gear Vendors O/D). Then there's the 2.48:1 1st Gear, vs. 3.06:1 in a 4L60E. New driveshaft required. New/modified trans cross-member

With the TH400 and 4.11 gears I was running close to 4,000 RPM at 70 MPH with street tires. The GV lowered it to a bit above 3,000 RPM.

**Jeff Green** · 02-08-2018, 09:10 AM

Unless you're over 1200 HP there is no good reason to go to a 400. If built right a 4L60E can take up to 1300 HP and you can put a brake on a 4L60E.

I had a Rossler 4L60E in a 4500 pound Impala and got it to a best of 9.2 at 157 MPH. There is a video on u-tube that someone took of the Impala on a test pass that shows 9.4 at 153 MPH and that was on a 4L60E with a factory ten bolt rear end and at 4500 pounds. I think you can find the video searching "Jeff Green 9.4". The video quality is bad but it shows what can be done.

In a Camero that weighs 1000 pounds less or more, you should never hurt a 4L60E if its built right. You should be able to run it into the 8's with a lighter car.

So my vote would be not to put a 400 in your car.