Anyone else use a crash box sometime?

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dibbons

dibbons

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Back in the 70's I had someone grind every other tooth (forget the name of that part) from the innards of a A833/3.09 low gear four speed. I was warned never to shift into second, third, or fourth except using a full power shift. Well, the return road from the end of the 1/4 mile drag strip seemed so long (4.56 rear end) that I began to fudge a little and would shift into second on the way back to the pit area. Before too long, I blew all of the teeth off of third gear (during a power shift into third, it seemed like I had shifted into neutral). I guess it was just as well, I replaced the crash box with a prepared full synchro Mopar, close ratio four speed and my E.T.'s improved some (still power shifting, of course).
 
This was the trick set up in the 60's and 70's. Poor mans liberty! You could up shift them with no problem. Down shifting was the problem since every other tooth on the syncros were ground off. If you got good you could speed shift without the clutch. Some guys tried to run them on the street, just had to double clutch and shift aggressively.
 
I believe it was called the "slick shift" modification. Every other spline from the sliding rings and every other engagement lug were ground flush. The synchro rings were removed.

On the track you shifted it quick and hard. Who cared how long it lasted. On the street you had to double clutch and it had a lot of backlash. Who cared how noisy and miserable it was.
 
Yes back in the day I ran (I hate to say it but I ran a Minice M22) I would grind every tooth off the brass blocker ring and every third tooth off the syncro this would allow clutchless up shifts but to down shift you did need you to double clutch or it would not go in very well. After half a season you would have to pull the trans and go through it most of the remaining teeth would be sharp as a razor and they snap off then and the trans was toast.
 
Slick shift is the correct name for that mod. I always thought it was a stupid mod that usually always leads to failure and gains very little if anything over someone who already knows how to speed shift. No offense.
 
hi, we ran mopar trans, 3.09 set. had the gears modified by GER . they machined off the small teeth and welded on a pro ring. they had their own sliders and hubs. the splines were very heavy duty. the sliders were bullet proof. you could up shift and down shift this setup. we had this done in 1979. retired the trans in 2009. only maintenance required was
welding up the lugs and machine them down bout every 500 runs, which was bout 5 years of use.
 
Well, I got one for ya.
-After being frustrated with the way my boxes werent keeping up at 7200, I got busy.Since Im a streeter and am running the GV, I decided to slick shift just 2nd and 3rd.But I changed it up a bit.I wanted to keep the brass for street manners.I didnt care about 4th, and obviously 1st didnt need it.
-So what I did was to cut out every second clutch tooth on the gears, and on the slider I just cut every second tooth back about 5/16 inch or so.This tripled the space between engaging teeth.Since I only cut back the synchronizer teeth part way, backlash was not increased and I was able to retain the brass rings and their energizing system.
-Now it works no differently than a regular tranny when Im just tooling around. But it has this extra feature.It shifts like butter at high rpm, actually any rpm. I am easily able to overpower the brass, and just slam that puppy in there.Winner.
-That tranny has maybe 8 summers on it and Ima guessing 40,000 miles on it. I must admit, Ive replaced the brass on 2nd a couple of times.And it needs it again.But the clutch teeth are fine. Im a streeter.
-This is a very worthwhile mod. And no I dont need to shift at 7200. But the motor is still pulling pretty hard up there, and it sounds so wicked,sooo excuse me while I get my fix.
-Aw man, I can hardly wait for spring.
 
That was an old trick used in the late 60's and through the seventies. You ground off every other tooth on the (synchronizer) "sic" ring gears. It was great for racing applications, but it sucked trying to down shift using it as a street application.
 
This is called a slick shift. Libertys can do it for you still to this day if you dont want to. But why not just Faceplate 2-4th?
 
Same thing about third gear happened to my brother last summer. Third gear is the weak link in an 833. That's the word from Passon performance so I would just go with the "that's racing" thing
 
Yeah, back in the day aka the good ole days. Back then I was running Gen ll hemi and the 833 with gear ratios running from 4.56 to 5.13. Doug Nash was producing the heavy lug gears with two of every three splines of slider taken out. It worked well. This was a car dedicated to drag racing so there was no worry about what it would do on the street. They were "good old days!"
 
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