6 speed conversion

[Guest]

so decided that i want to do a 6 speed conversion rather than rebuilding my 5 speed but just wanna know is the box diff driveshaft and cv's all i need for the conversion??? has anyone done this conversion and is there any custom fabrication necessary??

[Guest]

some one needs to write up a sticky.

[Guest]

my understanding you will need:

gearbox, gear linkage, diff, propshaft, drive shafts, hubs and rear brakes from the V7 to do the complete conversion.

cheaper option; find a 3.9 diff, then you can retain your hubs and shafts. (pending your car of course)

But happy to be corrected if that's wrong

[readosnr]

im going through this process at the moment for my gravel car.

1993 ra which is getting a ver9 6 speed.

i have plenty of subframes and driveshafts etc so will be able to swap and move around to figure out what works.

i have:

-6 speed ver 9 Spec c box (with external oil cooler lines)

-Cusco twin plate clutch with sti plates

-6 speed clutch slave

some issues i will need to look at are

-front drive spindles and what axles they fit

-centre driveshaft- auto will probably work

-gearbox crossmember- hopefully a 5speed will work. gc auto one wont fit.

-rear diff will probably just have the crown wheel and pinion replaced to accomodate the factory lsd. or source a complete sti ra 3.9 rear end with hubs, axles and brakes

-gear shifter- who knows

- ecu to run the dccd

[Guest]

i heard u can use your 5 speed clutch on a 6 speed box?? so if u use the 3.9 diff is that the r180 ones?? could i use my factory rear subframe and cv's and hubs??

[readosnr]

not sure about using the 5mt clutch and not going to worry either as already have the clutch.

the r180 is 3.9 however you should be able to source a 3.9 out of some auto's so you can still use your subframe and axles.

[Guest]

yea that would save alot of $$$ rather than getting new cvs and uprights with the r180, do u know in particular wat autos run 3.9??

[Johnnynz]

 capster said:

i heard u can use your 5 speed clutch on a 6 speed box?? so if u use the 3.9 diff is that the r180 ones?? could i use my factory rear subframe and cv's and hubs??

I think you can use the 5 speed clutch.

I have no experience with this so dont take that as gospel, there used to be a sticky in this thread before the board collapse on how to do a 6 speed conversion.

If you sit tight another day or two someone with the knowledge should pop up as I know theres a few guys lurking who have done this conversion.

[Pappu1]

u can use a 5 speed one but aperently it has fewer bolts (?)

the flywheel has to be 6 speed tho

(thats what i gathered : )

[Tony]

 pappu said:

u can use a 5 speed one but aperently it has fewer bolts (?)

the flywheel has to be 6 speed tho

(thats what i gathered : )

nah Pappu, if you use a 5 speed clutch you use the 5 speed flywheel, and you also have to use the 5 speed starter motor. Likewise with the 6 speed clutch.. use the 6 speed flywheel, and you have to use the 6 speed starter motor.

Here is my list of what you will need for the conversion:

6MT box

6MT gear shifter assembly (with reverse lock out)

6MT or WRX/Impreza AUTO prop shaft

3.9 ratio rear diff to suit your set up (whether it be R180 or R160)

6MT Clutch Fork & Slave Cylinder

The gearbox subframes are the same for the 5 speeds so you can just use a 5 speed one if you dont have the 6 speed one.

The gearbox mounts look to be pretty much the same and you can use the 5 speed one (as in it will fit) but it may not be as strong due to the weight difference between the 2 gearboxes...

Front axles will be dependant on what type of 6 speed you are fitting. The newer ones do not have the stub axles coming out of the front diff so you will need the "male" inner CVs to suit, otherwise for the earlier boxes (Ver. 7 & 8) use the normal "female" inner CVs so most peoples original axles will be fine.

Pretty sure thats all.... I may have forgotten a couple of little things but will post up again if I remember anything else...

[Optical]

in addition to the above:

5 speed clutch slave seems to work with the 6 speed fork

the 5 and 6 speed main gearbox mounts are different heights, the 6 speed one is about 10mm shallower

[Pappu1]

 Tony']

[quote name='pappu said:

u can use a 5 speed one but aperently it has fewer bolts (?)

the flywheel has to be 6 speed tho

(thats what i gathered : )

/quote]

nah Pappu, if you use a 5 speed clutch you use the 5 speed flywheel, and you also have to use the 5 speed starter motor. Likewise with the 6 speed clutch.. use the 6 speed flywheel, and you have to use the 6 speed starter motor.

ahh.. yes thats what is tru -

last yeara mate did a 6 speed conversion to a B4 and used the r180 diff but had his axles modified to suit the hub

if u use the 6speed rear diff, you will need the 6 speed hubs or modify your axles end to suit

personally modding the axles is the weaker option as after some driving the axles broke lol

[Optical]

who'd your mate get to modify the axles pappu? A mate is doing something similar soon

[Guest boostcut]

theres an engineer in tauranga... gear cutting specialists who re splined a ford 9 inch for me less than a week ago.... ace job and customer has fried many a tyre since and is fine so measure up and send to him..... if you want ph number pm me

[Guest]

A crap load of effort for no reason. Just get a decent diff for you 160 rear and keep it simple.

By all means waste your money if you like though.

The 160 rear diff has proven to handle upwards of 350+kw@w

I would only be concerned with the 160 if you are doing a RWD conversion and plan on drifting every weekend.

[Guest loren]

 WRXJIM said:

A crap load of effort for no reason. Just get a decent diff for you 160 rear and keep it simple.

By all means waste your money if you like though.

The 160 rear diff has proven to handle upwards of 350+kw@w

I would only be concerned with the 160 if you are doing a RWD conversion and plan on drifting every weekend.

That makes me feel good. I just spent a reasonable amount of money and effort upgrading my R160 and was worried

I should have just bought an R180.

[Pappu1]

 Optical said:

who'd your mate get to modify the axles pappu? A mate is doing something similar soon

some engineering shop in avondale..waste of time i must say..

best to get new gears cut on a metal rod then cut and weld option..

[Guest]

pappu.

You should have asked me mate, I have had a V7 6speed set up in my car for about 5yrs now.

I went all out though. I used front and rear V7 subframes, CV's, hubs, brakes etc.

Basically I used the complete v7 running gear just to make sure everything would work.

It all fits with no p*ssing about.

I recommend using the 6 Speed flywheel , clutch and starter and R180 etc.

I have found that the gear ratios are mind blowingly even keeping the engine well into boost with every change.

You should call me and come for a spin.......... you will sh*t yourself.

[Treecrusher]

I've got a 160 3.9 rear diff for sale if you want it.

[Guest]

I'v done a 6 Speed conversion on my 89 Legacy.

Ran with a V7 STI 6 Speed Gearbox and subframes and gear linkages etc

Used stub axles from my 5 speed gearbox

R160 3.9 Rear Diff.

Auto 4wd Driveshaft.

Used my 5 Speed flywheel and clutch

Used 5 Speed Clutch fork

Used 5 Speed Starter Motor

Used 5 Speed Slave cylinder,Just had to shorten the shaft a little

Used all my standard axles and cv's etc

So far no problems and everything running good.

[readosnr]

whats the go with the starter motor bolt/stud?

my box is a ver 9 (so 8 bolt bellhousing) and the ver9 starter motor uses 2 bolts, which travel through the bellhousing and into the engine (8 bolt)

however my engine is a phase 1 closed deck block (4 bolt type)

do i

-helicoil the lower hole in the bellhousing and make a large stud?

or

-drill out the block and tap a hole?

[nt_a_foz]

Iv picked up a v8 6sd, rear diff an axles and driveshaft. These will all bolt up to my type r factory hubs right?

[Tony]

 readosnr']

whats the go with the starter motor bolt/stud?

my box is a ver 9 (so 8 bolt bellhousing) and the ver9 starter motor uses 2 bolts, which travel through the bellhousing and into the engine (8 bolt)

however my engine is a phase 1 closed deck block (4 bolt type)

do i

-helicoil the lower hole in the bellhousing and make a large stud?

or

-drill out the block and tap a hole?

Just use the 1 top bolt to hold the starter on.... I have been running it like that for over 3 years on my race car with no issues.

[quote name='nt_a_foz said:

Iv picked up a v8 6sd, rear diff an axles and driveshaft. These will all bolt up to my type r factory hubs right?

Yep, will be fine - your original rear axles will fit into the diff as well, so keep the V8 ones as spares

[Optical]

I drilled and tapped the hole through the 6 speed bell housing as i had a 12x1.5 tap lying about. But as Tony says it seems to be fine with only one bolt

[nt_a_foz]

 Tony']

whats the go with the starter motor bolt/stud?

my box is a ver 9 (so 8 bolt bellhousing) and the ver9 starter motor uses 2 bolts, which travel through the bellhousing and into the engine (8 bolt)

however my engine is a phase 1 closed deck block (4 bolt type)

do i

-helicoil the lower hole in the bellhousing and make a large stud?

or

-drill out the block and tap a hole?

Just use the 1 top bolt to hold the starter on.... I have been running it like that for over 3 years on my race car with no issues.

[quote name='nt_a_foz said:

Iv picked up a v8 6sd, rear diff an axles and driveshaft. These will all bolt up to my type r factory hubs right?

/quote]

Yep, will be fine - your original rear axles will fit into the diff as well, so keep the V8 ones as spares

So i could use either axles??

Im picking id want to use the v8 ones wouldnt i as if i remember right they are much thicker than the gc8 one??