I am putting a side shift Lasalle behind the flathead six Mopar in my HA/GR. It has seen previous dragster use, evidenced by the lack of the first/reverse mainshaft slider, a steel shift shoe, and a lockout bar on the first/reverse shift shaft. It also shows signs of abuse and repair on the outside, in addition to at least five different paint jobs over its life. anyways, I want to try more "tricks" on this trans, but has anyone here ever raced or heavily modified one of these things? I want to cut the first and reverse teeth off the cluster- anybody got a cluster with BAD low teeth? The other option here is to cut that part of the cluster off entirely, remachine a new bearing surface at the rear, and make a tube spacer. I have read/heard that it is/was common practice on other trannies to "take every other tooth off the slider" to make it into a "crash box" for faster/clutchless shifting. I'd like to try this, so I asked my local manual trans guy about it- it would entail grinding out every other tooth for the third gear shift either off the synchro or the inside of the input shaft. Anybody have any thoughts on this?
I've done this a few times including a 13 speed Truck Tranny. You remove teeth on the slider and its counterpart or syncro gear (taking the brass completely out or grinding all the teeth off), the teeth count can't be a Prime number like 5,7,11 and so on. On my 3 speed I had to take 2 teeth off, leave 1 and so on, depends on your teeth count with the goal of having even tooth spacing. You will still need to bump the clutch to get it out of gear but it will go right in to the next one. I hope our HA/GR buddies arn't on to us Rocky
Sounds like a whole bunch of work for nothing to me. I ran a stock floor shift lasalle behind a Cadillac mounted in a Henry J in the late fifties. I had 6" slicks and would get the revs to 5000 in second gear and pop the clutch to launch. When the tach hit 600 grand I would shift to third. Going through the lights I was turning 6000. I was turning 112 mph @ 12.90 ET. Blew the engine, but the trans was still good.
the thought process behind all this -- I don't have alot of horsepower, and the sideshift Lasalle is reputed to be slow shifting. I will lose rpm during the slow shift,and not have the horsepower to pick it back up- so, by reducing rotating mass I should be able to transfer more power to the rear, and by speeding up the shift I should lose less rpm. End result? quicker ET. Ain't that what drag racing is all about?
bringing this one back to the top for some additional info-- I tore into my trans last week, it does indeed have the steel shift shoe, and the 1/R slider is gone, but there's a mod I hadn't read about in a Lasalle, so I thought it was worth mentioning;; It appears the syncro has been disassembled, had spring tension removed, and then was reassembled. I've never seen one of these syncros apart, so I am assuming there are springs inside that have been cut to reduce pressure??? Presumably this is to speed the transition as the ring is moved from 2 to 3. one other note- I have no clue what power this trans was behind, but it must have been substantial, because the output splines, where they have been machined to the Ford output 6 spline, show signifcant twisting!!
The Jalopy Journal
