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den001

rb25 box conversion

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im gona burn my car,

 

having dramas wiv the clutch bearing not pushing the pressure plate enough due to a 12mm adapter plate fitted to the sr block to take a rb box...

 

im running a rb25 carrier and bearing,

 

id like to know if sr20 ones are longer than rb25 ones??

 

as if it was the case then it would solve all my headaches....

 

cheers

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nissan make 14mm all the way through to a 28 mm carrier(28 ish mm was a while since i looked), also there are a few different bearing thicknesses, also pivot ball thicknesses (and on top of that washers to space it out more). You can trial it with the box out of the car using a straight edge and a ruler.

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hey mate what adapter plate did you use? got a link or something?

cheers.

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os giken have the part numbers and the lengths listed on there website some where get

 

hunting

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what about this fir a idea, if i get a new bearing that pushes onto the carrier which is 12 mm fatter than the original, it should compensate for the adapter plate and then should be ok...

 

i hope sr20 clutches are the same as rb25 clutches, as i will have abit of play with the pivot..

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The carriers actually go longer than 28mm - the Nissan part numbers are listed on this page (which is for a Z32 gbox behind an SR) Z32 GB into S13. The bearing is pressed onto the carrier and you can also put a spacer to push it out further - I put 7mm as said in that thread, resulting in 35mm. You can also place a washer under the clutch fork pivot to crib a bit more space.

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all sorted......

 

alot easier than taking the box out again, especially wiv no hoist..

 

i modified the pin that goes into the slave cylinder, made it 14mm longer than the original,pushed the cylinder into the bore, and re-bled the system, now the pedal is unreal, there is no slop in the pedal when instantly pressed, im yet to drive it as waiting for my tailshaft 2morro but it feels perfect, very very happy

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all sorted......

 

alot easier than taking the box out again, especially wiv no hoist..

 

i modified the pin that goes into the slave cylinder, made it 14mm longer than the original,pushed the cylinder into the bore, and re-bled the system, now the pedal is unreal, there is no slop in the pedal when instantly pressed, im yet to drive it as waiting for my tailshaft 2morro but it feels perfect, very very happy

 

you HAVE to have free travel in the pedal, jump under the dash and adj it before it f**ks your clutch, also make sure its now not pressing on the fingers all the time as the clutch will slip

 

if you have to pull the box out again this is how you measure it

 

1. Push and hold the throw out bearing right back in the gearbox

2. Wile holding it back, measure from the front surface of the throw out bearing to the front surface of the gearbox that bolts to the motor, Write that number down eg 70mm

3. With the clutch in the car, and the pressure plate on, measure where the throwout bearing will touch the fingers to the front face of the clutch eg 10mm

4. Now where you measured the gearbox face before, measure that same spot of the motor to the front face of the clutch, (that you measured in step 3) eg 76mm

 

Now math time

 

You need to find the distance from the motor to the fingers, 76mm-10mm=66mm now the gearbox face to throw out was 70mm so you have 4mm space left, perfect

 

Had to do mine the other day and it has 5-6mm a little more is ok (z32 gearbox on a s13 with twin plate clutch

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there is about 10mm of free travel in the clutch pedal b4 the slave starts moving, i was under the car while my mate was testing the pedal, the forks are not engaging until the peday is pressed more than 10mm

 

this should be ok i hope

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under the dash on the clutch pedal is the adj for free travel, id advise you to put a little bit in the pedal or your going to be buying a new clutch LOL

 

free travel adjusts how much travel the slave is going to get, with 10mm obversely its not going to get f**k all, you can adj the free travel under the dash so you get full amount of travel at the slave, but if throwout carrier is too short will run out of adjustment blah blah lol

 

good luck dude

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hows the shifter look under your radio? and no input shaft locating in the spigot right?

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shaft is in the spigot, i used a 12mm adapter plate, but the shifter is shit... i am getting a custom one made up....

 

hows your $1600 powertune kit??? LOL, they ass raped you didnt they :)

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No doubt the powertune kit is expensive, too expensive for what it is I agree.

 

did you machine down the bellhousing?

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the powertune kit is mad, but well overpriced, if it was repriced to round the 1000 mark i would have definatly buy it...

 

no, the bell housing was left standard, the shaft goes into the spigot about 9 to 10mm, we tested it with paint, fitted the box then pulled out, my engine builder uses the exact same setup and his car runs mid 10 sec passes with very harsh launches on full slicks, so i have seen first hand that it does the job..

 

the shifter is in the worst spot and im getting a custom one made up now so it will look completly standard inside the cabin...

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you've lost about 50% of input shaft/spigot placement and missing even more splines to locate into the clutch plate, and 50% missing is waaaaay too much IMHO but hey if your mech backs it up and you like it then by all means :thumbsup:

 

 

here's an idea for your shifter :) should post up pics of yours :)

P1280075.jpg

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^^^ dude, what kit are u using with the rb25 box?

 

ive recently done the rb25det conversion behind a sr20 in a s15 also. also for bearing carriers, the longest one you can get is approx 43mm long off a gq nissan patrol.

 

im using a hks twin plate gd pro clutch in mine.

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0h forgot to add with the pivot balls you have two choices. the sr20 box ones are around 20mm long or you can use the rb25/vg30 one that is 40mm long.

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mine sits like that aswell, your bearing carrier will be ok as u have a twin plate, less travel needed....

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OH! It’s too sad your car burns and I am happy you are don’t waste your car in the garbage and remake this. you can need any financial help then just visit my official site https://assignmentman.co.uk/ and request money I will give you because I love the cars lovers.

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