13b To Gm Auto Trans Adapter ?
06-25-2004, 09:20 AM
#1
Junior Member
Thread Starter
Join Date: Jun 2004
Posts: 2
i have searched high and low and cant find anyone that does a rotary to gm automatic transission adapter ...
has anyone heard of seen or know where to find this adapter ?
ati racing has one on their website but they dont build them or have plans too
thanks in advance
has anyone heard of seen or know where to find this adapter ?
ati racing has one on their website but they dont build them or have plans too
thanks in advance
12-18-2004, 10:32 AM
#6
Fabricator
Join Date: Jan 2004
Location: Central Ohio (Hebron) Zephyrhills Fla.
Posts: 1,322
wanklekrawler,Jun 25 2004, 06:20 AM]
i have searched high and low and cant find anyone that does a rotary to gm automatic transission adapter ...
has anyone heard of seen or know where to find this adapter ?
ati racing has one on their website but they dont build them or have plans too
thanks in advance
Not gettin much help here are you?
One of my race transmissions is a Richmond Gear Road race trans. It has bolt patterns on the front face to fit Chrysler, Ford or Chevy bell housings.
To fit it to the rotary I used a Chevy S-10 manual bell housing. The small Chevy bell housing is almost the same size as the rotary bell housing. Two of the bolt holes actually line up and can be used in connecting up to the rear iron. I made and adaptor from a piece of 1/4" steel plate stock. I cut out a circle from the center to clear the flywheel. I drilled two holes to pick up the dowel pins in the rear iron. I drilled through the mating surface of the bell housing with an 1/8" drill bit in two opposite locations. I drilled the 1/4" plate through any location where the rotary iron had a hole. Where possible I installed a stud in the plate and welded the back side of the plate so the stud could not unscrew. I TIGed on two lugs to the bell housing to pick up the two bottom engine bolt holes.
With the plate bolted tightly to the rear iron, I assembled the engine less the rotors. I mounted the dial indicator on the counter weight and put the indicator against the inside of the bearing retainer hole in the bell housing. I turned the engine over many times, and moved the bell housing around until I got zero runout on the indicator. That indicates that the center of the bell housing is exactly in line with the center of the crank.
I then clamped the bell housing to the engine in 4 places, and checked the runout again. I then drilled through the back of the dowel pin (1/8") holes into the steel plate. I installed 1/8" pins in the steel plate from the front and TIGed them in place and ground the weld sites flat.
The Chevy pilot shaft is just a few thousandths smaller than a RX shaft so there is nothing to do there. The shaft was a bit too long, so I made a 1/8" aluminum spacer plate to fit between the trans and bell housing. I use a top mounted starter.
A Tilton 2 disc 5 1/2" clutch. The discs are for the 15/16" Chevy fine spline. And a Coleman coaxial release bearing.
About the same system will work for an automatic. The hang up will be that the full size bell housing may be too big for fitting in the car. But then there were automatic S-10s. Alter a Chevy flex plate to bolt to the rotary counter weight, or redrill the counter weight to the chevy bolt pattern (we do that). Then you can use the chevy starters.
Piece of cake. About one weekend.
Picture is the Richmond Gear trans.
Lynn E. Hanover
i have searched high and low and cant find anyone that does a rotary to gm automatic transission adapter ...
has anyone heard of seen or know where to find this adapter ?
ati racing has one on their website but they dont build them or have plans too
thanks in advance
Not gettin much help here are you?
One of my race transmissions is a Richmond Gear Road race trans. It has bolt patterns on the front face to fit Chrysler, Ford or Chevy bell housings.
To fit it to the rotary I used a Chevy S-10 manual bell housing. The small Chevy bell housing is almost the same size as the rotary bell housing. Two of the bolt holes actually line up and can be used in connecting up to the rear iron. I made and adaptor from a piece of 1/4" steel plate stock. I cut out a circle from the center to clear the flywheel. I drilled two holes to pick up the dowel pins in the rear iron. I drilled through the mating surface of the bell housing with an 1/8" drill bit in two opposite locations. I drilled the 1/4" plate through any location where the rotary iron had a hole. Where possible I installed a stud in the plate and welded the back side of the plate so the stud could not unscrew. I TIGed on two lugs to the bell housing to pick up the two bottom engine bolt holes.
With the plate bolted tightly to the rear iron, I assembled the engine less the rotors. I mounted the dial indicator on the counter weight and put the indicator against the inside of the bearing retainer hole in the bell housing. I turned the engine over many times, and moved the bell housing around until I got zero runout on the indicator. That indicates that the center of the bell housing is exactly in line with the center of the crank.
I then clamped the bell housing to the engine in 4 places, and checked the runout again. I then drilled through the back of the dowel pin (1/8") holes into the steel plate. I installed 1/8" pins in the steel plate from the front and TIGed them in place and ground the weld sites flat.
The Chevy pilot shaft is just a few thousandths smaller than a RX shaft so there is nothing to do there. The shaft was a bit too long, so I made a 1/8" aluminum spacer plate to fit between the trans and bell housing. I use a top mounted starter.
A Tilton 2 disc 5 1/2" clutch. The discs are for the 15/16" Chevy fine spline. And a Coleman coaxial release bearing.
About the same system will work for an automatic. The hang up will be that the full size bell housing may be too big for fitting in the car. But then there were automatic S-10s. Alter a Chevy flex plate to bolt to the rotary counter weight, or redrill the counter weight to the chevy bolt pattern (we do that). Then you can use the chevy starters.
Piece of cake. About one weekend.
Picture is the Richmond Gear trans.
Lynn E. Hanover
12-18-2004, 02:37 PM
#7
Senior Member
Join Date: Jun 2004
Posts: 524
The problem with using Chevy starters is that all GM products I am aware of mount the starter to the engine side of the flywheel - no starter mounts on the transmissions.
Wonder if it'd be possible to use the top mount starter and space it up to mate to a GM flexplate? There are two sizes to choose from, 153 tooth and 168 tooth.
Additional info, there are three different common GM bolt patterns. Chevy, used on the 2.5 four, the Chevy V8s, and the 90 degree Chevy V6s. BOP, used on Buick, Oldsmobile, and Pontiac engines, as well as Cadillac engines. And then the Chevy 60 degree, which is used on 90% of the remaining engines introduced after 1980, mainly front-drive applications. There a couple oddballs in the mix but they are not common engines and none were rear drive.
Wonder if it'd be possible to use the top mount starter and space it up to mate to a GM flexplate? There are two sizes to choose from, 153 tooth and 168 tooth.
Additional info, there are three different common GM bolt patterns. Chevy, used on the 2.5 four, the Chevy V8s, and the 90 degree Chevy V6s. BOP, used on Buick, Oldsmobile, and Pontiac engines, as well as Cadillac engines. And then the Chevy 60 degree, which is used on 90% of the remaining engines introduced after 1980, mainly front-drive applications. There a couple oddballs in the mix but they are not common engines and none were rear drive.
