DIY: Swapping SR Bell Housing to KA Transmission

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PantherRacer
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Emperor_Tha wrote:Is it possible to swap parts from the de to the det like swaping 1st 2 be and 3rd gear?
Long answer I've seen it done in other tranny's, and I think it has been done in the Nissan transmissions too. So it should work. The only thing different would be the tooth count on the gears. But you have to get the backlash (spacing between teeth) and endplay (In and out movement of the input shaft) correct. You'd also have a slight power drop going into 4th with the shorter 3rd gear I believe. If you get a trained professional who knows what he is doing then there shouldn't be a problem.

Short Answer: Yes, but you have to make sure your measurements and adjustments are correct.

Remember the formula: The higher the number for the ratio, the lower the gear. This equals more torque multiplication, which translates into lower 1/4mi times.

The lower the ratio number, the higher the gear. This equals better fuel economy, and higher top speed.


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Thankyou

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efrain240sx
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HIJACKER I need youre help again. I tried this and i thought i got it right, but when I put the trans in the car I notice that when I started the car and let go of the clutch the trans is in gear even do the shifter shakes like if it's in neutral. Did I accidentally live it in gear?

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Hijacker
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Sounds like you did.

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efrain240sx
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Man that sucks, now I have to take it out and do it all over again

r1jlewis
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hey guys, very useful write up! but does anyone happen to know if the bell housing from the s15 6speed will fit the ka tranny? cause the 6speed is in like 3 sections (bell, gearbox, tail section) mine just craped out on me last week at the track and it doesn't seem to be cost effecient to fix that thing. Also, any one tried looking at a z32 tranny to a sr bellhousing???

Mattlanta
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^^^^ That's exactly what I was wondering! I basically want more top end for the track and the bonus of having better gas mileage on the highway/street. I don't care about 1/4 mile and prefer not to have to row row row so much Sounds like the KA would be an improvement, but now I'm wondering what other options are out there!!!?!??!

This thread is awesome and thanks to everyone who offered up info, especially Hijacker for creating it!!!

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240sxHitman
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thanks for the great write up. i just completed this process but i only took off the bellhousing off each tranny.

Thumbs up to hijacker!!

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Hijacker
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It's a good question about the Z gearbox and the SR bellhousing. As far as I know, the S-chassis trans stuff won't fit the Z-chassis trans stuff. The dimensions, I think, are different.

And one of the main reasons I recommend pulling the tail housing off is that I always end up breaking the seal between the aft section and the sandwich when I try to knock the bellhousing loose from sandwich plate. But like I said, if you lay it the trans on the side and use a rubber mallet on the input shaft, you should be able to knock just the bellhousing loose. Provided you have someone/thing to hold the bellhousing still.

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240sxHitman
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hijacker i have a question, with switching bellhousings does that change how much fluid you put in?

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Hijacker
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no

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yessir240
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My sr tranny just messed up on me. The plate that the input shaft goes through that the pivot ball screws into, well the sleeve coming off of that split at the end preventing the throw out bearing from doing its job which in turn cracked and bent my fork and actually broke the sleeve off of the forementioned plate.1) what would cause this to occur2) it seems like that plate are identical from Ka and SR transmission are they infact?are the clutch forks the same as wellthanks=brad

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yessir240
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Modified by yessir240 at 1:56 PM 6/5/2008

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yessir240
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help sry

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kentuckyslider
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Switched to a 4.36 JDM rearend 2 days ago and dropped 2nd gear in my sr tranny today. Found a KA tranny for $75. I will be doing this swap next weekend. Are the gears just as strong in the KA as in the SR. I will be drag racing with wrinkle walls, 4.36 R&P, and a 2 step. Maybe I should by 3 or 4 KA tranny's.LOL

Kouki3935
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Will the s15 6 speed bell housing bolt up to a KA tranny? Has anyone tried it?

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Hijacker
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Totally different bellhousing to gearbox bolt pattern between the 6 speed and the 5 speeds

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AllDayDrifter
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great write-up i need to find me a ka trans lol

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needfaster240
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Hijacker wrote:Totally different bellhousing to gearbox bolt pattern between the 6 speed and the 5 speeds
OK WILL THE S15 6SPD FIT THE S13SR???

Da240sX
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nice write up man,thx,i got a question.my sr tranny is going out soon.i just bought a ka tranny,does any one know if my sr clutch is going to fit into the ka tranny?thank you

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Hijacker
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The spline count for the KA trans' input shaft is identical to the SR's, so in short; yes your SR clutch will work with the KA trans. The reason you see people not using SR clutches on KAs is due to the bolt pattern of the flywheel. The SR flywheel will not bolt to the KA crank, and the SR pressure plate can't bolt to the KA flywheel (unless you have it redrilled properly).

NEEDFASTER. I LIKE CAPS LOCK TOO. But, yes the S15 6 speed will bolt to any SR block. You need the flywheel, clutch, transmission, and rear differential from an S15 as well as a custom driveshaft.

blackmagic
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alright well I just did this swap and went to put the driveshaft on got 2 bolts on and had to spin the driveshaft but it wont move. I checked the e-brake and thats down. Then checked if it was in neutral and found that the shifter wont move. Then I went to start the car to see if it was in neutral and the wheels started spinning even with the clutch pressed in. Im thinking I put the fork and the throwout bearing on wrong... what do you guys think. the tranny i swaped it with worked perfect on my friends old ka actually it was a rebuilt tranny. I have been searching for an hour and a half under clutch fork, throwout bearing, tranny stuck in gear, and many more but nothing. Im not realy in the mood to drop the tranny again just to find that it was somthing simple so ill wait for some feedback. thanks guys.

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needfaster240
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Hijacker wrote:NEEDFASTER. I LIKE CAPS LOCK TOO. But, yes the S15 6 speed will bolt to any SR block. You need the flywheel, clutch, transmission, and rear differential from an S15 as well as a custom driveshaft.
thank you for your help!!! i've been trying to found out before i start my build. i'll let you know how it goes. why does it matter if you change the rear diff or not???

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GoinTopless240
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Oooo Oooo.. I know this one.. pick me.. lol. You are not going to like my answer though. You have to pull the trans again. I did this like 10 times out of the car. Then i put it in the car .. still stuck. Pulled it out of car and took bellhousing again. I'm sorry but I think I deleted the pictures already, but I will try my best to explain it to you. Take trans out of car. Remove bellhousing (I know .. this part sucks.. taking the front shaft cover, clip, gasket..etc). The trans you got is probably from an S14, but there is a small difference between the SR bellhousing and KA bellhousing. You have to grind a tiny area on SR bellhousing to make everything work. You are going to be angry that it is what it is, but it works. Trust me. 2 mins of grinding and everything works. Here is the picture. Look at your KA bellhousing to see how tiny an area that needs to be ground. Go find something soft to punch and then go get some more gasket sealant. Go get started with pulling trans. Good luck.[IMG][/IMG]

blackmagic
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alright sounds good im not mad its easy to pull the tranny i found a way that makes it so easy. just unbolt everything to the point you can move it back and forth the turn the tranny upside down and pull out it doesnt hit the firewall. takes like 10 min. to get out cause you gotta wiggle. haha. ill try your idea. thanks

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Hijacker
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GoinTopless240 wrote:Oooo Oooo.. I know this one.. pick me.. lol. You are not going to like my answer though. You have to pull the trans again. I did this like 10 times out of the car. Then i put it in the car .. still stuck. Pulled it out of car and took bellhousing again. I'm sorry but I think I deleted the pictures already, but I will try my best to explain it to you. Take trans out of car. Remove bellhousing (I know .. this part sucks.. taking the front shaft cover, clip, gasket..etc). The trans you got is probably from an S14, but there is a small difference between the SR bellhousing and KA bellhousing. You have to grind a tiny area on SR bellhousing to make everything work. You are going to be angry that it is what it is, but it works. Trust me. 2 mins of grinding and everything works. Here is the picture. Look at your KA bellhousing to see how tiny an area that needs to be ground. Go find something soft to punch and then go get some more gasket sealant. Go get started with pulling trans. Good luck.[IMG][/IMG]
The KA trans in this write up was from an S14, but I've done S13 KA trans swaps as well and have never had to grind any metal off of the SR bellhousing.

blackmagic
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The tranny im using is an s14 ka tranny. i guess ill just try it and before i put the tranny back in the car see if it shifts into all gears. if not then im back to square 1

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GoinTopless240
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Hey Bart, I think it might be a year to year thing. My SR bellhousing was a 93 S13 and trans came from a 95 KA. I took apart that trans like 10 times and each time, as soon as I would tighten the bolts on the midplate - poof ! It would lock up. I'd take it apart, check everything. Everything spun like butta out of housings. Put it back together.. spin spin.. tighten bolts - poof ! Locked up again. By chance I was looking at where shift rods traveled through and I saw it. I ground down that little corner on the S13 housing and Viola` - everything worked perfect. Maybe I just got a freak unit (95 was the bastard year afterall), but it sounds exactly like my problem. I'd feel bad if I didn't say anything though. Just my .02. Bart is the god when it comes to this write up.. no question. Just a tweak that worked for me.

Da240sX
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[QUOTE=Hijacker]The spline count for the KA trans' input shaft is identical to the SR's, so in short; yes your SR clutch will work with the KA trans. The reason you see people not using SR clutches on KAs is due to the bolt pattern of the flywheel. The SR flywheel will not bolt to the KA crank, and the SR pressure plate can't bolt to the KA flywheel (unless you have it redrilled properly).QUOTE]

thank you for the quick reply.hmm....so in order to use the ka tranny in the sr bellhousing....i need a ka clutch,ka flywheel and ka pressure plate?

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GoinTopless240
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Shouldn't need to change that stuff if you are swapping the internals. I'm still using the whole clutch set-up that came with my SR swap (Ogura Super Single 409). In fact the only thing that really changed is 5th gear and it's better for cruisin on the highway (about 300 rpm lower at 70 mph = better mpg). Input shaft count is the same, so the SR clutch thinks it's an SR trans. The only real difference is the bellhousing. I even used my SR tailhousing (KA unit tailhousing was cracked on end). Good luck with it.
Modified by GoinTopless240 at 9:39 PM 12/20/2008


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