johnnyb

I've transplanted a LS1/4L60E combo from a 99 camaro into my 66 Chevy II/Nova. I've switched to the 01 LS6 cam and springs and Corvette stainless exhaust manifolds. I'm using a low restriction inlet and straight thru track mufflers so there is very little intake and exhaust restriction. I'm running 3.48 gears. I've utilized LS1 edit to turn off VATS, update the gear ratio, lower the cooling fan on off temps, and turn off trouble codes for all of the non-transplanted equip . The problem I'm running into is when starting from a dead stop the engine revs super quick in drive and doesn't shift automatically to 2nd and bangs the rev limiter (6200 rpm) within 2-3 seconds from starting from a dead stop. If I back off the throttle it shifts to 2nd and shifts fine with resumed WOT into third. I've lowered the 1st-2nd WOT shift point with LS1 edit to as low as 4500 with no success. The other significant difference is the Chevy II only weighs 2800 lbs versus 3600+ for the Camaro donor. It shifts fine manually and everything else works great. I've double checked the trans fuid level and the fluid's not burnt. I'm not getting any misfire codes so I'm sure I'm bouncing off the rev limiter. I'm thinking about increasing the heavy to full throttle trans line pressure but I don't want to be making any more changes blind. What do some of the more experienced out there think?

jimmyblue

iTrader: (11)

Stock program upshift speed at WOT is 125MPH.
However base-model cars on low-speed-rated
factory rubber got speed limiter values lower than
this (116MPH?) I believe. Check that you are not
getting snagged by something like this; also that
the basic speed values are sensible (matched to
gears & wheels).

Sounds like the shift MPH is your problem and the
shift action starts when you have satisfied both RPM
and MPH at WOT. Part throttle is MPH only.

johnnyb

I checked and it looks like LS1 edit automatically edited the shift point mph's when I changed the rear ratio and tire diameter. It's set to 1st->2nd shift at 34 mph. It shifts fine 2nd->3rd. You may have misunderstood part of my post, I'm not having a top speed issue but a WOT automatic 1st->2nd shift while shifter is in drive.

johnnyb

The guys over at LS1-edit were very helpful. The issue was the way autometer recommended wiring the speedo. Once I removed the speedo input from the VSS to the PCM circuit and used the speed output circuit from the PCM the car shifted beautifully. This was a puzzler cause the scanned speed and the speedo were reading correctly, just a bit jumpy. Now that it's shifting correctly the car goes like a bat outta hell. I weighed it and dry it's 2850, this combined with the LS1 with the z06 cam and pretty open intake and exhaust.....

cablebandit

iTrader: (37)

is it fast?

johnnyb

I havn't taken it to a track yet but checking it with a watch on some long freeway onramps it goes 0-80 in 5 seconds or less . Be interesting to see what it does in a 1/4..........