Hi guy, I have a jap 5speed box out of a gh sigma, I have just turned my 4 speed in to metallic soup...
Now I pulled out the 4 speed and started to put the 5 in and came across a problem... The flywheel ? The 5 speed clutch doesn't fit on to the original mounting holes ?
Just wondering wether I can use a sigma flywheel or I need new clutch(i have a excedy heavy duty)
Thanks liam!
Gh sigma 5 speed to 4g32
- wheelbarrow
- Posts: 52
- Joined: Thu Mar 26, 2009 5:30 pm
Re: Gh sigma 5 speed to 4g32
Yep you will need to use the astron flywheel, clutch and probably the starter motor too. you will also need to open up the shifter hole in the floor. the trans mount will need to be changed, to suit the trans. either out of a lb lc lancer 5spd if you can find one or cut and weld your own. also change the tailshaft yolk to the sigma one too. Its a bit of mucking around but worth it.
Re: Gh sigma 5 speed to 4g32
Problem there will be that Astron flys are 6 bolt and Saturn are 5 bolt.
Are you sure the gearbox isn't wide block?
I was under the impression that all narrow block clutches are interchangeable (Saturn, Astron and early Sirius)
I have a 4g63 DOHC 6 bolt (early Sirius) flywheel on my narrow 4G54 (Astron) running a 4G52 (Astron) pressure plate and using a Triton 4G63 SOHC 6 bolt (Sirius) clutch plate. All connected to a Triton 4G63 gearbox
Are you sure the gearbox isn't wide block?
I was under the impression that all narrow block clutches are interchangeable (Saturn, Astron and early Sirius)
I have a 4g63 DOHC 6 bolt (early Sirius) flywheel on my narrow 4G54 (Astron) running a 4G52 (Astron) pressure plate and using a Triton 4G63 SOHC 6 bolt (Sirius) clutch plate. All connected to a Triton 4G63 gearbox

Re: Gh sigma 5 speed to 4g32
is there a difference in 5 speeds from GH's to GE's ?? i got my 5 speed from a 4G52 GE sigma and it bolted straight up, perfect fit?? no changing of the flywheel or clutch, no changing the driveshaft, only mods i had to do were getting a lc lancer gearbox mount and opening up the shifter hole a little.
Re: Gh sigma 5 speed to 4g32
I have a narrow 5 speed here that has a larger input shaft than the others I have, I found this out the hard way, I got a engine box combo, but the box in my car was good so I just put the engine in, when I went to drive I had nothing, as the clutch on the engine was big shaft and the gearbox was little shaft, I changed cutch plates to fix this,
spoto a 57 chev
...a 57 2 door
...a 57 2 door
Re: Gh sigma 5 speed to 4g32
Sorry to jack the thread but this means i can use the 4 speed flywheel and clutch?
Re: Gh sigma 5 speed to 4g32
I have used the 4 Speed flywheel and clutch with no problems other than the clutch being a bit tired and having the occasional slip (age/usage more than anything wrong with using a 5spd) this is with a 5 speed out of a GE which is the year model before, as far as i know its the same as a GH box
Re: Gh sigma 5 speed to 4g32
Modgalant wrote:Hi guy, I have a jap 5speed box out of a gh sigma, I have just turned my 4 speed in to metallic soup...
Now I pulled out the 4 speed and started to put the 5 in and came across a problem... The flywheel ? The 5 speed clutch doesn't fit on to the original mounting holes ?
Just wondering wether I can use a sigma flywheel or I need new clutch(i have a excedy heavy duty)
Thanks liam!
What I have found is that the Astron Cluch is a larger diameter than the 4G32 so it doesn't bolt straight onto the 32 Flywheel. Which is what Modgalant is saying. BUT as Jono says there is no need to use the astron clutch just use the Flywheel and clutch from Saturn 4 speed.
If you can't change from 4 speed to 5 speed in a couple of hours you're doing something wrong
- LukeAussie
- Posts: 353
- Joined: Fri May 18, 2012 9:55 am
- Location: Adelaide
Re: Gh sigma 5 speed to 4g32
Not that I'm adding much here, but my 5-speed is from a Jap Lancer and was an easy swap (once the hole for the shifter was cut).
If the flywheel and clutch fits, then it shouldn't matter much. But isn't the problem that one is four stud and another five?
Good luck either way!
If the flywheel and clutch fits, then it shouldn't matter much. But isn't the problem that one is four stud and another five?
Good luck either way!