Which 4 Speed Will Work
- Thread starter paden5971
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Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
We have a few threads here that address this issue, this is a swap I started way back and have not moved forward with to any extent:
http://www.forums.IHPartsAmerica.com/transmission-tech/911-Scout-80-t18-four-speed-swaperoo.html
And this one goes with the above:
http://www.forums.IHPartsAmerica.co...pancake-bellhousing-4-spd-11-inch-clutch.html
In order to install the t-18 for a four cylinder s800 (t-18), you will need the pancake bellhousing which is unique to that application so that the engine will remain in it's original location and relationship to the peripherals.
http://www.forums.IHPartsAmerica.com/transmission-tech/911-Scout-80-t18-four-speed-swaperoo.html
And this one goes with the above:
http://www.forums.IHPartsAmerica.co...pancake-bellhousing-4-spd-11-inch-clutch.html
In order to install the t-18 for a four cylinder s800 (t-18), you will need the pancake bellhousing which is unique to that application so that the engine will remain in it's original location and relationship to the peripherals.
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
Lee!
I never made the connection between your user name and your real name! Sorry!
Good to talk with you this morning!
This pic is the front of a t-18/pancake bell used behind a 196 inna s800 (model year unknown). This is the "short input shaft" version we discussed.
For identification purposes, this input shaft "stickout" measures 8-3/4" from the flat on the outside of the front bearing retainer to the flat tip of the input shaft that enters the pilot bearing.
The depth of the "pancake" bellhousing measured from the front machined surface to the transmission machined surface is identical in dimension to the bellhousing used with your 152/t-90 setup in your s80 now. So all the additional bulk regarding the t-18 conversion is behind the bellhousing, the t-18 is approximately twice the dimensions in all respects as compared to the t-90.
I'd recommend retaining the existing s80 d18 transfer case since it's output shaft location is correct for the driveline angle for your rear axle. If ya go with a d20, then ya really need a rear axle with a centered pumpkin as was installed onna s800.
Need more pics or measurements??
I never made the connection between your user name and your real name! Sorry!
Good to talk with you this morning!
This pic is the front of a t-18/pancake bell used behind a 196 inna s800 (model year unknown). This is the "short input shaft" version we discussed.
For identification purposes, this input shaft "stickout" measures 8-3/4" from the flat on the outside of the front bearing retainer to the flat tip of the input shaft that enters the pilot bearing.
The depth of the "pancake" bellhousing measured from the front machined surface to the transmission machined surface is identical in dimension to the bellhousing used with your 152/t-90 setup in your s80 now. So all the additional bulk regarding the t-18 conversion is behind the bellhousing, the t-18 is approximately twice the dimensions in all respects as compared to the t-90.
I'd recommend retaining the existing s80 d18 transfer case since it's output shaft location is correct for the driveline angle for your rear axle. If ya go with a d20, then ya really need a rear axle with a centered pumpkin as was installed onna s800.
Need more pics or measurements??
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Thanks, that should be good, but your explanation with the t case has me thinking now, I have a set of narrowed d44 being built for this rig with 4 wheel disk brakes, they are not the tapered shaft version? I saw them a few weeks ago and the pumpkin is in the middle of the rear axle. Can I still run the s80 d18 transfer case setup, or do I now need to find all parts for the 4 speed swap to get any time behind the wheel this summer?
As always thanks.
As always thanks.
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
A centered pumpkin rear axle is always preferable with the rear output location of a d20 transfer case.
An offset (to passenger side) output location is preferable with a d18 such as the Scout 80 had , whether the d27 or the "option" d44 tapered hub axle.
So...if you are having a centered d44 fabbed, then the d20 is preferred. But...the d18 will be ok though it May eat u-joints periodically. The slip joint on your existing driveshaft should provide adequate travel to move it towards the driver side and still have enough engagement...but double check that as it will depend upon how much arch ya got in the springs and the ride height with weight on the springs. It's possible that the driveshaft might need to be lengthened for optimization, but it's final length can't be accurately determined until weight is on the tires and ride height is established.
Don't mean to confuse ya! Alotta folks find and swap in a d44 out of a Scout 800 which fits perfectly on the s80, but then the driveline angle is compromised...it does work...but the offset is not conducive to optimum life expectancy of the u-joints.
Since your axles are being "built", then have the fabricator cal'c the rear pinion yoke "face" angle/spring perch mounting so it's parallel with the transfer case output shaft yoke face angle. That is what u-joints like!
Same for the front, but after the spring perches are optimized for pinion angle with the transfer case, the the axle housing "c on each side should be twisted to optimize king pin inclination and spindle assembly caster.
We shoulda had a longer talk yesterday, now that I know what ya got going on, we coulda addressed this and I would not have confused ya!
An offset (to passenger side) output location is preferable with a d18 such as the Scout 80 had , whether the d27 or the "option" d44 tapered hub axle.
So...if you are having a centered d44 fabbed, then the d20 is preferred. But...the d18 will be ok though it May eat u-joints periodically. The slip joint on your existing driveshaft should provide adequate travel to move it towards the driver side and still have enough engagement...but double check that as it will depend upon how much arch ya got in the springs and the ride height with weight on the springs. It's possible that the driveshaft might need to be lengthened for optimization, but it's final length can't be accurately determined until weight is on the tires and ride height is established.
Don't mean to confuse ya! Alotta folks find and swap in a d44 out of a Scout 800 which fits perfectly on the s80, but then the driveline angle is compromised...it does work...but the offset is not conducive to optimum life expectancy of the u-joints.
Since your axles are being "built", then have the fabricator cal'c the rear pinion yoke "face" angle/spring perch mounting so it's parallel with the transfer case output shaft yoke face angle. That is what u-joints like!
Same for the front, but after the spring perches are optimized for pinion angle with the transfer case, the the axle housing "c on each side should be twisted to optimize king pin inclination and spindle assembly caster.
We shoulda had a longer talk yesterday, now that I know what ya got going on, we coulda addressed this and I would not have confused ya!