Gen3 hemi tkx swap

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The longer 833 input shaft uses the inner pilot hole of the early engine crank. Too long for gen 3 hemi. The Tremec with the Ford short shaft uses the outer crank register for pilot bushing or bearing on mopar similar to Ford.
Could the Ford TKX have gotten the shorter GM shaft?
Just quickly looking at my quick time bell for big block mopar to TKX measurements the shaft length is .090 less than depth of bell. The crank extends roughly an inch out of the block. The bearing is in that step. Should be good. Yeah I know I need to get the clutch and pilot bearing stuff bought and I would know.
I am getting nervous on bell issues. The QuickTime does look cooler than the Lakewood.
Crank on the gen 3 only sticks out .500 from block not like the old school stuff
 
Got some good news I guess for the bellhousing. We are going to use it. I’ll have to make a custom pilot bushing that’s a little longer. After measuring everything out the clutch disk will ride right at the very end of the spline of the input shaft. Won’t be running a spacer in between crank and fly wheel.
My only concern is how much travel the throw out bearing has.. at full travel to the snap ring the rotation stud is looking like it’s at the very end. How far does it travel? I have .75 bore master.


For now I got the brake lines made and e brake lines ran with studs and line clamps. Ready to paint the housing.

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I was wondering how that was going with the bell. SST or American power train does not make a stepped pilot? Doesn't take much to make it but?
A bit of extra space there for the hydro throw out too. A shallower bell would be nicer but glad it's working.
What gear ratio and tire size you running?
I like the build of your car. Very nice work and combination. Thanks for the pics of the progress.
 
I was wondering how that was going with the bell. SST or American power train does not make a stepped pilot? Doesn't take much to make it but?
A bit of extra space there for the hydro throw out too. A shallower bell would be nicer but glad it's working.
What gear ratio and tire size you running?
I like the build of your car. Very nice work and combination. Thanks for the pics of the progress.
Thanks. I’ll keep them coming. I haven’t found a stepped pilot for this application. I’ll be running a 255/60 drag radial with 4:30 gear
 
Been putting the front suspension on. Hdk kit is very nice. I had stock strut bars in it with the factory rubber so I made a front adjustable arm. Initially I had someone spin up the rear mount and made an arm to the front with rod ends and clevis style mount in the front. After the install I put it through travel and it bound up pretty bad. I think Chrysler had rubber on the front side so it could sorta telescope through travel because it’s not swinging at the same arch as A arm. Finding out that I raised the rear point high as I could. Now it will freely move and not want to pivot the lower arm in… spindle parts should be here tomorrow and hopefully welded by the weekend.
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Been putting the front suspension on. Hdk kit is very nice. I had stock strut bars in it with the factory rubber so I made a front adjustable arm. Initially I had someone spin up the rear mount and made an arm to the front with rod ends and clevis style mount in the front. After the install I put it through travel and it bound up pretty bad. I think Chrysler had rubber on the front side so it could sorta telescope through travel because it’s not swinging at the same arch as A arm. Finding out that I raised the rear point high as I could. Now it will freely move and not want to pivot the lower arm in… spindle parts should be here tomorrow and hopefully welded by the weekend. View attachment 1716249879

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That's a nifty idea! Does the fact that it ends up a tad shorter cause any issue?
 
My only concern is how much travel the throw out bearing has.. at full travel to the snap ring the rotation stud is looking like it’s at the very end. How far does it travel?
Shouldn't be a lot. Isn't there a spec in the instructions?

Several years ago I put an American Powertrain hydraulic throw out bearing in my '68 Coronet. While not a Tremec with an aftermarket bell, one would think it's the same idea. Target travel/air gap on that part was .150". .200" is too much and .100" is not enough.

The bearing is really not supposed to retract. The operation is similar to how disc brakes work. The bearing rests on the clutch fingers like a caliper piston would on a spinning rotor. You want it to have instant action and if it has to travel real far then it will be delayed and will take more pedal travel to fully disengage the clutch.

BTW, I used the factory clutch pedal and clutch rod to give the right pedal ratio - it was the right move. I cut one end of the clutch rod off and drilled/tapped it to accept the threaded rod that actuates the master cylinder. The OE rod end is actually angled already so there was a slight offset to the right. I had to clearance the inner opening of the firewall plate a bit to keep the rod from contacting it at full travel but that was it. It's more important to have the correct amount of travel.
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I drove it thousands of miles like that without issue. Hyd. throwout was one of the best things I did to the car, worked beautifully.
 
Slanted Darts scenario is different than yours. He has extra space between throw out and clutch. His crank flange is shallower on the gen 3 hemi versus small block. Quicktime lists the bell housing being the same when the gen 3 bell should be shallower.
That's what I believe was the issue.
 
Slanted Darts scenario is different than yours.
Maybe I misunderstood but he asked specifically how much travel the throwout bearing should have? The concept is simple and should be the same no matter what the application. There should be very little travel for the reasons I gave. Too much travel and you'll potentially push the piston out of the bore.Too little travel and the clutch won't disengage.

He has extra space between throw out and clutch. His crank flange is shallower on the gen 3 hemi versus small block. Quicktime lists the bell housing being the same when the gen 3 bell should be shallower.
That's what I believe was the issue.

I had a similar issue putting a 4 speed into a car that was originally a 727 because of the shallow pilot bore. I did a lot of measuring trying to avoid doing this but I ended up having to cut the end of the input shaft by almost 1/2". It's actually not uncommon to have to do that. If the stack up is off, do what needs to be done to make it work. Trimming the input shaft won't hurt it as long as the area within the pilot bushing or bearing makes full contact with the I.D.
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If I'm missing something, I apologize and disregard what I suggested.
 
No worries. What you said was relevant and correct. I may have missed something.
I am hoping to be as happy with my hydro clutch as you are with yours.
 
Impressive! Very cool, I like your design.

Are you going to market it? Not something I can use, just curious.
Hopefully . I’m going to to some R and D with them first. Take them on a drag week and drive them around Michigan. If they survive that then yes.
 
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Got one spindle welded up. All looks good. Track width will come in about a 1/4 inch have to countersink the ball joint bolts. Just wanted to see what it looks like assembled first.
 
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Got some progress going on. Got the rear end in and assembled. Came out pretty good. Minimal swearing. Had the custom pilot bearing made. Clutch and pressure plate went in pretty smooth. Trans was a little tricky by myself on the floor. My body hates me, I need a hoist.. Need to run the parking brake cable from the dash to the duel cables and get a shifter handle made up from something. Weather is getting perfect and I need to get some break in miles in
 
Update. It’s running and driving! The car is very fun and pulls hard. Need to make a real shifter lever and boot for it. Gear mesh noise is kinda loud without one along with the heat.. I’ve never had a manual car before so I’ve had to get used to using my left leg for the clutch. Little jerky at first.. the car is very fun and can wait to hammer on it after the break in period.
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Update. It’s running and driving! The car is very fun and pulls hard. Need to make a real shifter lever and boot for it. Gear mesh noise is kinda loud without one along with the heat.. I’ve never had a manual car before so I’ve had to get used to using my left leg for the clutch. Little jerky at first.. the car is very fun and can wait to hammer on it after the break in period. View attachment 1716275351View attachment 1716275352View attachment 1716275353View attachment 1716275354View attachment 1716275356View attachment 1716275355View attachment 1716275356View attachment 1716275357View attachment 1716275358View attachment 1716275359

What’s the switch in the last picture for?
 
Any updates? Make it to a drag and drive?
Updates yes. I’ve been driving it everywhere over the summer. Probably won’t go back to an automatic! Very fun. Took it to the track. Had a hard time launching it. Only had single adjustable shock on the back. Now it’s got strange doubles on the back and in the process of installing a clutch tamer. The ET is terrible but it went 122 mph no matter how bad I shifted.
 
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