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Ok so i have an r31 with an rb20 gearbox in it, the rb20 box was rooted and clutch was faaaaarked so i went and spent all my

money on a 5 puk ceramic cutch and wicked pressure plate to help out with the power im planning on making

heres the issue I did soooo much research called jap wreckers to double check and everyone said the SR20DET gearbox was identical to the RB20DET gearbox

so all i had to do was change my current bellhousing and hey presto the car will live again...... so stupid me went out and got and SR20 gearbox.........

and people NO it was not the same..... it LOOKS pretty close but the SR20 gearbox is 40mm longer.....

so now im stuck with a driveshaft that wont fit on my 31, poor me what to do i thought looked up some more info and apparently the auto driveshaft is 40mm shorter than the manual one

all u gotta do is change the actual bit that goes into the back of the gearbox to the manual one, the yoke or sumthin like that. anyway had a look and NO WAY

the caps on the manual are smaller than the ones on the auto so the yoke thingy wont transfer over :down:

i was told my only other option was to get it cut welded and balanced, but i didnt want to do that untill i got an RB25 gearbox to match it up right away

so does anyone hav any advise? im really stuck

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the reason i didnt buy and rb20 is because they r way too expensive for what they are, and i want to get an rb25 box anyway the sr was just to get the car moving again.

unless u know where i can get a cheap rb20 box?

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Oh man, if only one of us had come across this problem just days earlier. Only 2 days ago I paid a mechanic to swap my SR20 bellhousing onto an RB20 gearbox I got cheap and only once it was bolted to the engine we found that it was 50mm shorter. What a waste of time, it's not worth getting my tailshaft lengthened so I'm shopping for an SR box instead. I drove 5 hours return to look at one today that was f**ked.

So for the search record:

CA18 and SR20 gearboxes are the same length

RB20 are shorter!

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well the cheapest in SA currently is 500 and for a temporary gearbox thats just way too much, call any jap wrecker in sa and they all want 6-800 depending on condition of the box

the box i really need is RB25DET which i could pick up for 1000 so paying half that amount for a box im only gonna use for like 1000km just isn't cricket

and i stress the word again TEMPORARY i dont need to keep this gearbox i just need to get around in it untill i have the 25 box and associated bits to fit it to the 31

and god id love one from SA which costs 350, seriously id go and grab it tonight to stick it in tomorow, so if u selling a RB20DET gearbox in SA for 350 send me a msg and ill grab it....seriously

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if you only need it temporarily why not just hang off, save that little bit extra and fork out for the 25 box?

+1

stuff pulling the gearbox out twice when you dont have to......... Just save for the 25 box if you can get one for $1000

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