Wanted 13B-T 8 bolt flywheel (13405-58012)

[wormfood]

In best possible condition, if you can magically get a NOS one even better.

 

[rick_d]

So the 13bt and 1 hz use the same clutch disk. 1hz flywheels are 8 bolt. Trial fit. I think they interchange with blue block 13bts (not orange early blocks)

 

[joekatana]

So the 13bt and 1 hz use the same clutch disk. 1hz flywheels are 8 bolt. Trial fit. I think they interchange with blue block 13bts (not orange early blocks)

Small step from there to then go to the 300mm 1HDT flywheel and use a bigger clutch

 

[wormfood]

Small step from there to then go to the 300mm 1HDT flywheel and use a bigger clutch

Will that fit in an aluminum BJ7x H55f bellhousing? I thought the 13B-T flywheel was 300mm and used a 275mm clutch.

 

[joekatana]

Will that fit in an aluminum BJ7x H55f bellhousing? I thought the 13B-T flywheel was 300mm and used a 275mm clutch.

Flywheels are the same size but the machined surface diameter is different

 

[wormfood]

So the 13bt and 1 hz use the same clutch disk. 1hz flywheels are 8 bolt. Trial fit. I think they interchange with blue block 13bts (not orange early blocks)

My understanding is that the clutch discs are both 275mm and 21 spline, but the size of the splined shaft they fit is different. (28.9mm vs 29.7mm) Maybe it's close enough but I always thought splined parts should have a snug fit.

Anyways it seems I'll be going with a 330mm 14B flywheel (13405-56041) and 13B-T clutch kit.

 

[rick_d]

I have used a 21 spline mini truck clutch tool to set up both 13bt and 1hz systems (and the Isuzu disk on 300mm hdt system).

Repeating a conversion discovery from 1996 with the original party in 1999 using mini truck 21 spline centers from donor used disks, we dismantled 300mm factory 1HDT 14 spline disks, machined out the middle, press fit the cut down 21 spline mini center and TIG'd them in place. Then remade the 4 rivets and pressed the whole mess together before the ready fit Isuzu NPR disk discovery. This custom assembly fit 21 spline 1HZ H55 5 speeds (engaging with a mini truck center) thus allowing a cast iron transmission behind a 1HDT.

You can find 1hz used flywheels EVERYWHERE since production is 30 years old and began in 1990 and continues today. 14b's (a south american only rarity) are hard to find and a blue block 13bt was only made 1987-1989 (8 bolt). 1985-1987 orange blocks are 6 bolt flywheels.

In my experience 21 spline is 21 spline.