datsunlover Posted February 10, 2005 Share Posted February 10, 2005 Ok.. I had a thought.. "hey.. how about a KA 240sx 5 gear to replace my old 4 gear?" So I searched.. I found a little info, but I'm a little confused now.. there are conflicting statements.. Some posts say it bolts up but sits at an angle.. Some say you need to use the front of the Z tranny and attach it to the KZ tranny (How? Bolt it on? cut/TIG weld? ...??) One of the posts asked "arn't the L series a one piece case?" but there was never an answer.. From what I can tell looking at mine (75 280z 4 gear) I think it is, but... ?? I'm hoping someone has new info on this and could help me out.. Anyone runing a KA tranny? From what I gather, the Z clutch will work/line up, and some bearings have to be swaped... But, is a custom driveshaft needed? or is it possible the u-joints are the same? (IE: use KA piece out of the tailstock, and Z driveshaft..) Is it (trany case) a combo of KA/Z pieces, or what? I'm just gona run a mild N/A 2.8 so I'm not woried about how much power it'll take, I'm sure I won't break it. Hope someone can answer some of these for me.. PS; ZR8ED; I'm just curious, because I can get my hands on an 89 KA 5 speed for $100, and it's local. I wana see if it's an option, cause well.. you know the $$$ thing. I will let you know though. __________________ Quote Link to comment Share on other sites More sharing options...
GrayZee Posted February 10, 2005 Share Posted February 10, 2005 I saw a website on that once, it said to use the front of the Z tranny and the center and rear section of the KA tranny (meaning take both trannys completely apart and make one out of two) Found the link.. http://www.atlanticz.ca/zclub/techtips/240sxtransmissioninstall/index.html Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 10, 2005 Author Share Posted February 10, 2005 Cool man! Thanks for the link.. the pics really helped, and I think I understand how it works now. I'm a 2nd year machinest apprentice, and I can't see anything to dificult about this.. Just have to get all the parts in one place (my 3'x6' work area in front of the car ) and start playing.. I'm going tomorrow to check out the KA 5 gear in a wrecking yard and I'll see what happens.. Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 12, 2005 Author Share Posted February 12, 2005 Ok, I bought the KA 5 gear. It apears to be from a 91, body was rotten and the clutch was burnt so bad the friction disk pretty much disintegrated as I removed trans from engine ... but the tranny apears to be decent internaly. (all gears spin, had lots of fluid in it an no leaks) I spent the past 3 hours puling the stock 4 gear, and getting the two tranys cleaned up a bit. From what I'm seeing, the KA 5 speed WILL bolt right on, but will sit on an angle and aside from the fear of insuficiant internal lube at that angle, it would make the trany mount angled as well. So I will go through the change of bellhousings/boring out 1/2" hole and swaping the countershaft bearing. (Tomorrow hopefully, I'll post how it goes..) On to the tranny mount.. It seams the 5 speed is a bit longer (looks like 1.5" or less) but the front (belhousings) pieces are identical in length, meaning the rear section is longer, and coincidentaly the mount is about 1 1/8" further back. So here's what I've decided. After some measuring and figuring, I will use the Z mount (which has a flat piece w/two holes sandwiched between it and the trans) but modify it to sit forward 1/2". Basicaly weld the flat 'washer' plate to the mount half inch forward, and redrill through the mount. Then I will re-drill my motor mounts 1/2" forward or so, and it *should* all line up in the end. I'm aware this will put the fan quite close to the rad, and the oil pan closer to the x-member, but I think it'll clear. Now for the drive shaft.. If my 'shift' forward plan works, this 5 speed will still stick too far back to use the stock Z driveshaft.. by about 3/4" if I've figured this right. So.. I'm going to see if I can cut off the tip of the driveshaft yoke (looks like 1/2" at least before the splines start) and cut down the 'ring' to fit into the KA tailstock. I'm hoping this will be enough, but I have to wait a few weeks at least as my engine is out geting put back together, and I want the engine/trans siting bolted in the car when I figure out the driveshaft. If it needs shortening, so be it.. Quote Link to comment Share on other sites More sharing options...
kj280z Posted March 9, 2005 Share Posted March 9, 2005 Any updates on this? HAs there been any discussion about the amount of torque the 240sx tranny will support? Quote Link to comment Share on other sites More sharing options...
fl327 Posted March 9, 2005 Share Posted March 9, 2005 The ka trans is the same as an sr20det trans, gear ratio and all I believe, the internals are interchangible. Ive seen them take 350hp to the ground and hold up to all kinds of hard driving with a multi disk clutch, t51r hks turbo, jun head/ecu, and tons of boost. Ive seen them take clutch kicks/dumps/downshifts to no end and laugh at it. A good friend of mine has blown two KA motors drifting, blown two clutches into powder and has used the same trans behind both engines, and will be used for his third engine, as it makes no noises and shifts great. Crossmission gears from os giken and some other jdm to alter gearing,buddy uses these on sr20 car to be able to stay in second and modulate power better when drifting. NOW whose gonna go the extra mile, and convert the HKS sequential 6speed to a z bellhousing? Quote Link to comment Share on other sites More sharing options...
Ezzie Posted March 9, 2005 Share Posted March 9, 2005 The ka trans is the same as an sr20det trans, gear ratio and all I believe, the internals are interchangible. Not quite but very close. Gear ratios 1st - 4th are all the same but 5th is different. The KA24 tranny is a .759:1 and the SR20DET trans is .838:1. Apparently the diffs were slightly different ratios as well, the short nose R200 used in the 240SX for North America (S13 & S14, both open and viscous LSD's) all used a 4.083 final drive, the Sylvia & 180SX in Japan was a 3.692 final drive ratio. Quote Link to comment Share on other sites More sharing options...
fl327 Posted March 9, 2005 Share Posted March 9, 2005 The OD may be different but the internals do interchange without modification. I never heard of any s13/14 running anything taller than 4.08 though. Quote Link to comment Share on other sites More sharing options...
Ezzie Posted March 10, 2005 Share Posted March 10, 2005 I never heard of any s13/14 running anything taller than 4.08 though. Did some further research on Nissan FAST with this and the following are the R&P's that seem to have been used in the JDM market on S13's & S14's Nissan P/N Ratio Used on 38100-02M60 3.917 (47/12) SR20DET Auto 38100-03M60 4.083 (49/12) SR20DET Manual 38100-04M60 4.364 (48/11) CA18DET Don't know where I got that other ratio info from, may have been a boo-boo - can't validate it on FAST. Quote Link to comment Share on other sites More sharing options...
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