TKO 600 + Quick Time BH Space?

[lovehamr]

Working down to get my engine in my car and was mocking up the trans today. It's almost 15 thousandths off so some offset dowels are in route from RobbMC. Since I can't put the clutch in I decided to stab the trans and check it out. Glad I did. It slid in fine, nice and smooth. Then as I was looking closely I realized that it wasn't seated all the way. It's so close that, had I been laying under the car to do this, I'd have probably put the bolts in and cinched them down not realizing that there was a problem. And I'd probably have killed my engine the first time it fired. So after taking it back out of the BH I started taking some measurements. From the face of the trans to the tip of the input shaft is 7.11." The length of the pilot stub of the input shaft is 1.11" leaving right at 6" from the trans face to the end of the splines. When measuring from the rear face of the pilot bearing to the deepest part of the crank is 1.5" so I have plenty of room behind the pilot bearing. Measuring from the trans face of the BH to the rear face of the pilot bearing comes in right at 6", the same as the input shaft length to the end of the splines. So it looks to me like I have some interference between the rear face of the pilot bearing and the front edge of the input shaft splines. So here I am; the block plate is in place and the BH is bolted securely, the pilot bearing is fully seated and the trans won't go in. What would be some options? Does anyone make a shim that goes between the trans and the BH? I'm thinking 125 thousandths aught to do it. Or is there something more nefarious going on here?

[xlr8or]

I had the same problem and added a 3/16 spacer on mine. Can't help you on where to find one as mine came off a 3550 trans I already had that was bolted to a stock ford bell housing and I just re-drilled it.
You might try Mike Forte or one of the other vendors here.

[Blittleton]

lovehammer,

They make a shorter input shaft for the FE's. You can purchase one from www.ddperformance.com This may eliminate the spacer all together, like I said this may eliminate it or it may not. Definitely check.

Bill

[mikeforte]

Hi,
I read your post and have a few questions;
What engine do you have?
What bellhousing part number do you have?
If you have a BBF, you may need a short input kit depending on the bellhousing you have.
Did you use the correct clutch alignment tool with the correct size pilot?
I stock all the parts you have or need and know these for fitment.
Call me at wk 508 875 0016 and we can go over those questions to figure this out.

[lovehamr]

Thanks for the responses guys,
Mike;

Originally Posted by mikeforte

Hi,
I read your post and have a few questions;
What engine do you have?

66 428 FE block

Originally Posted by mikeforte

What bellhousing part number do you have?

Don't know right now, I'd have to run back home to get it.

Originally Posted by mikeforte

If you have a BBF, you may need a short input kit depending on the bellhousing you have.

If this were the case wouldn't the missmatch be much greater than a few thousandths?

Originally Posted by mikeforte

Did you use the correct clutch alignment tool with the correct size pilot?.

No clutch in it at the time, just the BH w/block plate and pilot bearing. Still have to center up the BH and didn't want to put the clutch in and have to take it right back out.

Originally Posted by mikeforte

I stock all the parts you have or need and know these for fitment.
Call me at wk 508 875 0016 and we can go over those questions to figure this out.

Just tried and a nice lady informed me that you guys don't open until 10:00.

Steve

[Blittleton]

The difference in the two input shafts are 5/8 in. I would measure to see if the spacer you are using with the bellhousing is that. Other wise I would buy an short input shaft from either Forte's or DD Performance. Throw out the spacer. And see what you come up with.

Bill

[kitcarbp]

Steve, the big block short input shaft for either the top loaders or the TREMECs are way shorter and obvious when measured compared to small block input shafts. Your issue sounds like something else.
Couple of basic things to start with.
Is there a machinging burr or step inside the pilot hole preventing the pilot bearing from seating all the way ?
The pilot bearing you are using, is it the solid type or are you using a more modern needle bearing type?
Have you compared your pilot bearing to others made for 428 FE's to make sure pilot the bearing is not mis-machined ?
Do you have the correct QT block plate thickness for the QT bell housing you are using? Speak to whoever sold you the QT BH to confirm this.
As an example (not FE) , my OEM block plate on a BB Ford (385 series motor)OEM bell housing is 0.070 inch thick, giving me a total distance from engine flange to BH trans face flange of 0.070+ 6.250 = 6.320" . I am using a TKO 600 with the short input shaft kit installed.

I am not familiar with FE crank pilot hole dimensions (others need to confirm).
1) Do 428 FE auto trans cranks and 428 FE manual trans cranks have different pilot hole dimensions (depth wise) that could be causing this?
3) Is it an aftermarket crank whereby the pilot hole may not be machined deep enough (to print)? In any case it sounds like you desire your pilot bearing to either sit a little deeper into the crank pliot hole, or you want a pilot bearing that is a little thinner to avoid the interference. If its the solid type I have heard of folks machining the thickness it to fit the crank pilot hole, but this is usually only required when doing engine/trans conversions from different manufacturers. I would avoid the spacer if you can and see if you can get the pilot bearing to seat further into the pilot hole.

EDIT
I just checked the QT website for both FE part numbers (RM-6056 and RM-6057) and both are listed as total height of 7.050" and the QT motor plates are listed as 0.125" thick, this would give you 7.175" with plate to the rear face of BH. You stated you measured "7.11" on the TKO face to input end. So I would bet it must be the pilot hole in crank, pilot bearing or its installation into said hole.

For ref here are the TREMEC specs, it shows 7.21 from trans face to input end on std (long) input shaft.


good luck

[mikeforte]

Hi Steve,
I'm sorry I missed your call today. Try my cell @ 781 248 8946 until 10:30 est tonight or anytime this weekend.

[lovehamr]

Thanks for all the responses guys. After a few PMs it seems to me that I wasn't getting across what I was trying to so I took a couple of photos with the BH, PB and trans in place but no clutch mech so that what I was trying to explain, I could show. This first pic is through the starter opening in the BH and you can see that the splined part of the input shaft is up against the pilot bearing.



The next image is looking at the gap between the trans and the bellhousing with the input shaft grounded as in the first pic.



As you can see there isn't much of a gap there and the PB isn't sticking very far out of the back of the crank. And I'm not using a spacer. The car is at BDR right now but when it gets back I think I'm just going to have about .250" machined from the front of the spline on the input. The disc will still have plenty of room and the trans will then seat in the BH without any pressure on the crank.

Am I missing anything guys? Steve

[Roger Bolick]

Yep, looks just like others I've seen. Good photos. Its a marginal clearance issue. Much better to catch it than tighten those bolts the one extra turn needed to seat that Tremec!

Machining a new transmission input shaft would NOT be my solution.

Putting a spacer anywhere in the drivetrain would NOT be my solution.

Machining the crankshaft would NOT be my solution.

Just get B50-HD bronze pilot bushing (1968 428 Mustang) and have the back side trimmed slightly, i.e. a step so as to not loose any bearing surface in the middle. Old PB can be removed with a AutoZone tool, blind bearing puller, (free with a $170 deposit) use the 2nd smallest one. Prefer the ones with a threaded shaft, but this will work. Its possible to swap this with the bell, clutch and PP in the car.

Attempt to upload rough cross section showing new pilot in original position in crank with Tremec fully seated (collides with input shaft) just tap the new PB in one more tap and you're done. (NAPA BRG B50HD $4.99, shop bill was $5, so $9.99 total)

[kitcarbp]

Good photos, Roger is right, dont machine the input shaft splines so that you have less contact with the pilot bearing. I would keep it simple, focus on modifiying the pilot bearing to provide the step Roger mentioned and give it enough relief/step to allow the crank thrust bearing to have its proper clearance (fore-aft) so you dont wipe out your thrust bearing. What I cant answer is the exact clearance you should end up with between PB face and splines since you need to account for some thrust bearing wear over engine life( using the solid bronze PB Roger ref above). The TKO input shaft end play when new is 0 to .004", so thats minimal but should be accounted for its input bearing wear as well.

After looking at your photos, I now wonder if the TREMEC TKO 10 spline short input shaft kit addresses this issue? Could the 10 spline shaft have the splines far enough away from the PB? or are they in the same location on the shaft as the 26 spline shaft. The 26 spline is the stronger way to go in any case.

[xracerbob]

[/IMG]Steve-
I had a similar issue although the trans/engine combo is different. I machined the pilot bushing so it would sit deeper in the pocket of the crankshaft and eliminate the interference. Worked out fine.

[lovehamr]

Really guys at this point I'm not going to pull out my bearing and put a bushing in its place just because it would be easier to machine to fit. I decided to go with a bearing because I think it's a better system than using a bushing. And yes I do know that bushings have been used since the Jurassic, I've replaced my fair share of them, but times move on. Several of you have said not to machine the input shaft but none has given a reason not to. Let's keep this going. If you don't think that the input shaft should be machined back a little; why not? As far a switching the shafts goes; the difference between the 2 shafts offered for this trans is 5/8" so no matter which one I use it'll be messed up one way or the other. With the exception of the block, everything in this setup is aftermarket and it simply looks like a stack of tolerances that is not working in my favor.

Steve

[kitcarbp]

Steve, Your picture shows no block plate being used ???. This is the plate that goes between the engine and trans and is also needed for correct starter alignment to ring gear. If you dont have it fitted, this would move the trans (input shaft and splines) about 0.070-.090 ". I cant tell from your photos if you have it fitted. If its fitted and you have the right one, ignore above.

[lovehamr]

That view is a very close view of the interface between the trans and BH, the front of the BH at the block interface isn't shown, but the Quicktime block plate is in place. I didn't measure it but I wouldn't doubt your range either.

Steve

[lovehamr]

Just a follow up for everyone who may be interested. Here is the input shaft with about .250" machined away.



Steve

[mikeforte]

Hi,
I had so .200" spacers made to fit between the TKO & bellhousing. That could fix the problem.
Call me tomorrow.

[lovehamr]

Already fixed now Mike. Wish I'd known about your spacers a month ago! LOL