Blevinator

Hello,
I am having a custom torque converter built by Jakes Performance.
I have a Katech LS3 with an ECS small blower cam. Specs on the cam are 220 228 585 on a 117 LSA. I will have an Eforce supercharger on top.
The question is : What should the max shift RPM be?
I am thinking 6600-6800?

Thank you

C7/Z06 Man

To get your best 1/4 mile from what I have read in the past and the way GM set the LS3 with the A6 to shift from the factory with the stock cam should be 7 to 8 percent above the hp peak.

EXAMPLE:

LS3 = 430 HP @ 5900 RPM

59 X 8 = 472

5900 + 472 = 6372 RPM shift point.

The LS3 with A6 in sport mode usually shifts between 6350/6450 most of the time in my car.

Wherever your cam is suppose to peak for HP (or dyno's) just add 7/8% to that number for a good starting point; than move the rpms up or down a little to see if your times improve.

Torque converters are another story. What your looking for is one that will give you a good launch (60 ft.) and then as little slip as possible. The stall on my stocker is around 1500 rpms tops (I launch around 1200) which is way to low for a really good 60 ft. but you "also" do not want the converter slipping up top. I have read that you should pick up 25/28+ mph from the 1/8 to the 1/4 mile with a good converter which has a low percentage of slip on the top end for your rpm range.

PS: Check some of the "auto trans" out in the C6 1/4 mile section and you will see that 25/28+ mph holds true most of the time. The last record I set in Grand Sport "Bolt-ons" I picked up 28.29 MPH from the 1/8 to the 1/4 mile.

realcanuk

The trans will last longer if you don't shift over 6500 and with your setup you probably won't gain much by doing so. I stretch 4th out more to cross the line.
Your setup makes a ton of torque early. I don't think you need to shift to high.
What stall are you putting?

Blevinator

I am having Jakes Performance build a trans \ converter setup for me
Trying to figure out a stall speed
They are asking me max shift rpm (to match the converter)
I think I will tell them 6500.

Thanks guys!