Forcefed86

iTrader: (4)

My combination is a little odd at the moment. I have an overly tight converter spec'd for a 6.0 (winter 6.0 rebuild planned). And I'm using a spare 4.8 I had in the shop to finish out the year.

With no 2-step limiter on the transbrake I can hit 15ish lbs at 5k "ish". Takes a good 3-4 seconds to get there but once it builds to 4200 and 6-7lbs, RPM and boost climb really fast.

Attempting to get a more controllable consistent launch out of it without grenading the stock glide case/gears. Chassis is 2900lbs race weight. 3.25 gear with a 28" tire. "3400" PTC 9.5" converter.

Do you think 5k+ is too high to set the limiter? I tried dropping the limiter down to 4500, and it won't build much more than 10-11lbs unless I sit on it forever. A 10-12lb launch last week was only good for a 1.50 60'. Looking to get back in the low 1.4x-1.3x range.





With a smaller S475, 5.3, 4600 RPM, I was pulling low 1.3x 60's on 24lbs off the t-brake. The converter was really loose down low though and didn't couple hard till 90' out or so. I think that saved my trans. I'm nervous launching at big boost and RPM with this setup.

Appreciate any input.

This was a 1.34 60'.

oakley6575

iTrader: (3)

Just set it where it builds the amount of boost you want to launch at..How much boost will it make with the 2 step on at 5k? You should be able to make more boost on the 2 step than off of it.

Forcefed86

iTrader: (4)

It doesnt' want to make much over 12lbs at 4500 on the 2-step. At 5k it will make more, but that was without the limiter.

Haven't tried 5k on the limiter yet. Wasn't sure if launching that high on the limiter was some kind of glide "no-no". I never see/hear of folks going that high on an LS.

I think the converter is doing odd things because it's sooo tight. I was seeing a 1500rpm drop on the shift and under 3% slippage up top last track visit.

-thanks

kjm

When is the next track outing? I see a new 4.8 record in the near future 👍