evildky Posted October 7, 2004 Share Posted October 7, 2004 it's the countershaft front bearing, you'll need a puller to remove them from each transmission, the beaaring from the L trans goes onto the KA countershaft with a few whacks of a mallet (soft face) Quote Link to comment Share on other sites More sharing options...
Hugh Posted October 7, 2004 Share Posted October 7, 2004 The KA transmission is far from bulletproof. It's built with a smaller output shaft than the SR20DET RWD transmission, and it breaks faster. If you put 400hp through it, expect it to snap either the input shaft or output shaft eventually. It will twist the shafts for a while before it breaks, though. (you can see where it twists them right on the splines) The synchros rip out of them pretty easily, and the gears will start shattering if you mis-shift or just shift poorly. If you manage to put it in between 3rd and 5th at full throttle, it will shear off 5th and reverse in one fatal swoop. (although the first four gears will keep working) The guys in the 240sx community are always looking for a way to upgrade transmissions to handle over 400hp. If you're looking for big power, I wouldn't waste the money or time to put a stock KA tranny in a Z. If you're looking for something to hold 300hp or so, it will do that just fine for a while... long enough to be worth it. My friend blew a few of them up when he had between 275-350hp, but they kept breaking teeth off the gears. When you put out 400hp, the shafts will twist and eventually snap. Quote Link to comment Share on other sites More sharing options...
evildky Posted October 7, 2004 Share Posted October 7, 2004 seems pretty close to the braking point of the T5, of course the ka's are more plentiful, and can be had for $50-$100 It'll take me a while to hit 400hp, and once I do I guess I'll have to look for other options, but maybe not, I'm not a big drag racer so I doubt I'll kill it so quickly it is definitly an upgrade fromt he 4 speed, the syncro's are thicker and the shafts seem to be beefier as well, and of course you add an overdrive gear fot the daily drivers Quote Link to comment Share on other sites More sharing options...
Guest brianglawson Posted October 7, 2004 Share Posted October 7, 2004 actually ka and sr trannies are the same except for bellhousing and 5th gear, int heory if you used an s15 diff(thats where the speed sensor is) you could put an s15 6 speed on a z with this kit Quote Link to comment Share on other sites More sharing options...
Hugh Posted October 8, 2004 Share Posted October 8, 2004 Actually, the KA and SR trannies have different output shafts. It's been proven... the SR has a beefier output shaft. If you break an SR tranny shaft and throw a KA tranny in, it will break even faster. If you're not drag racing, you'll be fine. The shafts snap on launches and shifts into second with lots of traction in my experience. You may still slowly twist the input shaft... but I would just swap trannies every now and then. Quote Link to comment Share on other sites More sharing options...
Bluto Posted October 8, 2004 Share Posted October 8, 2004 Nice info.. I just so happen to have a machineist freind who owes me a few favors.. I seems like sr motor sets with 6 speeds are harder to come by.. I wonder of what the avalibility for just a 6sd. trans would be? Even if it wasnt a feasible option.. just being able to grab a decent trans at the jy for the KAs is a blessing for me.. I fear the worst for my stock 76 4 speed trans after the new tubo motor gets broken in!! Thanks, Sam Quote Link to comment Share on other sites More sharing options...
Guest brianglawson Posted October 8, 2004 Share Posted October 8, 2004 never heard of that one... but i guess i have now:) Quote Link to comment Share on other sites More sharing options...
Hugh Posted October 8, 2004 Share Posted October 8, 2004 The SR20DET with 6 speed uses a 3.6 final gear. You don't want to run it with a 4.1 or anything that high. It's alright on a 3.9, but still kinda short. There were rumors a few years back about the 6 speeds being weaker because the gears are smaller to accomodate a 6th one... however, there's been nobody out there complaining of blowing them up. I think it would be great for a road car/track car that you're not drag racing in. Those trannies are expensive and sought after... you'd be hurting if you blew one up. Quote Link to comment Share on other sites More sharing options...
rustrocket Posted October 8, 2004 Share Posted October 8, 2004 I just got a reply to an e-mail i sent the guy. The cost of machine work is $225, turn around time is 1 day, ready to install. You supply bell housing and tranny. Hope this helps... -Rustrocket Quote Link to comment Share on other sites More sharing options...
evildky Posted October 8, 2004 Share Posted October 8, 2004 wow the only machining needed is to bore out the 1st-2nd shift rod to 5/8, unless he's boring out the case to use the KA's countershaft bearing, which I don't understand as the L series pops right on and of course fits the L series case Quote Link to comment Share on other sites More sharing options...
Guest PROJECTRB240SX Posted October 19, 2004 Share Posted October 19, 2004 The KA transmission is far from bulletproof. It's built with a smaller output shaft than the SR20DET RWD transmission' date=' and it breaks faster. If you put 400hp through it, expect it to snap either the input shaft or output shaft eventually. It will twist the shafts for a while before it breaks, though. (you can see where it twists them right on the splines) The synchros rip out of them pretty easily, and the gears will start shattering if you mis-shift or just shift poorly. If you manage to put it in between 3rd and 5th at full throttle, it will shear off 5th and reverse in one fatal swoop. (although the first four gears will keep working) The guys in the 240sx community are always looking for a way to upgrade transmissions to handle over 400hp. If you're looking for big power, I wouldn't waste the money or time to put a stock KA tranny in a Z. If you're looking for something to hold 300hp or so, it will do that just fine for a while... long enough to be worth it. My friend blew a few of them up when he had between 275-350hp, but they kept breaking teeth off the gears. When you put out 400hp, the shafts will twist and eventually snap.[/quote'] ONE YOUR WRONG.... THE KA AND SR TRANS CODE FOR CODE ARE THE SAME TRANNIES (DIFFERENT BELLHOUSINGS), I'VE GOT THEM BOTH SITTING HERE AND HAVE SWAPPED OUTPUT SHAFTS... EVEN SWAPPED GUTS OF A KA AND SR INTO RB CASES FOR STRONGER PARTS AND AVAILABILITY. THERE IS A GUY HERE IN AZ THAT HAS OVER 500WHP ON A STOCK KA TRANS....ITS STRONG BUT NOT BULLETPROOF, AND I FIND IT TRUELY HILARIOUS THAT YOU GUYS WANT TO BUY OUR OLD JUNK THAT WE'VE BEEN TRYING TO FIND UPGRADES FOR BECAUSE ITS THE WEAK LINK. THE SIX SPEED HAS A DIFFERENT INPUT SHAFT AND SPLINE SETUP FROM ALL THE OTHER ONES.... AND WOULD TAKE QUITE ABIT MORE FABRICATION TO GET TO WORK THAN A KA OR 5 SPEED SR TRANS. Quote Link to comment Share on other sites More sharing options...
Guest PROJECTRB240SX Posted October 19, 2004 Share Posted October 19, 2004 I NEED TO UPDATE THAT POST I JUST DID.... I HAVE A S13 SR TRANNIES SITTING HERE A S14 TRANS MAY BE DIFFERENT. Quote Link to comment Share on other sites More sharing options...
Guest 240zt Posted October 20, 2004 Share Posted October 20, 2004 Any pictures of this maybe a picture how to of sorts Ill host the pictures for you ! Quote Link to comment Share on other sites More sharing options...
Hugh Posted October 20, 2004 Share Posted October 20, 2004 I have a link for you to read from someone who did side-by-side comparison of the output SR and KA output shafts. His picture links are now dead, and I'm trying to get ahold of them to show you. Read the thread, you will see its coming from a guy ran 10.5 in the 1/4 mile with a 550hp SR20DET in an RX7 FD3S. He's very credible, no reason to BS anyone. http://forums.freshalloy.com/ubbthreads/showflat.php?Cat=&Board=UBB9&Number=67639706&Forum=All_Forums&Words=tnt&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=allposts&Main=67639594&Search=true#Post67639706 He states about halfway down that the KA output shaft is skinny before the splines, and the SR output is the same thickness all the way down. The SR output shaft will twist on the splines and break (I've done this and seen it done several times with 300-400hp) and the KA output shaft will snap before the splines where it is skinnier, and therefore WEAKER. I'm not BS'ing anyone here. I'm relaying fact. I've been building fast SR's for several years now. Quote Link to comment Share on other sites More sharing options...
Guest PROJECTRB240SX Posted October 20, 2004 Share Posted October 20, 2004 Ok now I know what your talking about. Yes, the ka trans has a step in the out put shaft and the sr is straight through..... You can buy SR OS Geiken Tranny poarts and use it in your ka trans as they are identical in everyway but the bellhousing and that little step. Quote Link to comment Share on other sites More sharing options...
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