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Keisler 5spd Installation - Write Up

  • Thread starter Thread starter PhilJustPhil
  • Start date Start date Jul 26, 2012
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PhilJustPhil

Member
May 28, 2002
36
1
8
Ottawa
Jul 26, 2012
#1
  • Jul 26, 2012
  • #1
Thought I'd write up the installation experience for a Keisler T45RS "Perfect Fit" 5spd into my '68 with Toploader 4spd & 390.

I ordered a complete kit back in November - transmission, cross member, clutch disc, driveshaft, pilot bearing, speedo cable, shift lever, etc. I wanted the swap to be as easy as possible with no extra parts chasing required. The hardest part of the installation was the wait time. It was on a 90 day lead time, with scheduled delivery for February. That slipped repeatedly, and I was plenty nervous for my deposit, made worse by them hitting my card for the remaining balance in April, and not delivering until it eventually hit my door at the end of June, 1 day before I was leaving on a vacation.

The week I got back, I dove into the manual, planning to use a day to takeover my workshop (I've got a composites fabrication business) and do the swap. Made easier since one of my guys used to be a licensed mechanic. Very conscious of the interuption this makes on the business, I wanted to be in and out in 1 day.

Dropping out the old crossmember and transmission was a piece of cake. The bellhousing for the 390 has an access plate that lets you drop the clutch out without removing the bellhousing. The old pilot bushing popped out with little effort.


Here's the old one out and the new one ready to go in. You can see the 5spd is considerably larger.

The first step on installation is to use a dial indicator to measure run-out between the crankshaft and the bore of the bellhousing. A challenge here as our dial indicator couldn't fit in exactly perpendicular to the bore, so the numbers were a bit suspect. Keisler allows you only +/- .005" of runout. This I wish I'd known at the time of ordering the kit, as I would have got their offset dowel pins at the same time (for adjusting the bellhousing position), just to be safe. The Ford service manual allows +/- .007" and that's what we measured. Good enough... this car doesn't get many miles put on it, and I wasn't about to take the time to source offset dowel pins while keeping the car in the workshop.

The new kit had a 3 part pilot bearing instead of a bushing, and required a good bit of force to get it hammered in to place. Then we went to install the new clutch disc, with the old pressure plate, and found the first problem. The hub on the new clutch disc was considerably longer than the original and was contacting the pilot bearing. Called Keisler technical assistance, and got some suspect advice: remove the pilot bearing and machine it down for clearance. Hunh? Well now the new pilot bearing wouldn't hydraulic out (grease just squeezed through the needle bearings) so I had to do a cross-city run to buy a pilot bearing puller at the one store we could find that had one in stock. Pulled the bearing and could see no reasonable way of clearancing it in the lathe. Eventually we had to move on, so we simply took a grinder to the clutch disc and ground the hub until we had reasonable clearance. All told we burnt about 3 hours on that issue.

The overall clutch assembly was still thicker than original and wouldn't install through the bellhousing access plate, so we had to back off all the bellhousing bolts by 1/4" (the top 2 are nearly impossible to get a wrench on to) to get additional clearance. Don't forget the clutch fork... we did the first time. With long tube headers, it won't install from the side.

Now to put in the new transmission. Although its "Perfect Fit" there is still a bit of cutting to be done - a dollar-bill size of metal has to be removed from a rib in the transmission tunnel, and the shifter hole in the tunnel needs to be clearanced 1/2" on one side to accept the shifter tower (alternatively you can play with your motor mounts to rotate the engine about 1 degree). By the time we were satisfied with the metal work, the day was done.

It would have been really nice to use guide studs to slide the new transmission into place, but there's no room for that the way its case is designed. In fact, you have to be very careful to get the 4 mounting bolts in while lifting the transmission into place (oh for a proper transmission jack at that time).
.

Next, the new crossmember goes in. It bolts in the original location but then sets back several inches. Luckily it just clears the Dynomax exhaust pipes.


In addition to the original set of holes, the cross member requires you to drill a 2nd set in the rib across the tunnel. Another challenge, as these holes interfere with the dimples on the underside of the rib... the bolts just barely fit.

It really looks like the cross member wants to be about 1/4" higher, but this is where it locates with the stock holes.

The drain plug looks obstructed too.


New driveshaft vs old. Good fit (longer case on the 5spd, so shorter driveshaft).

Finally, shifter arm goes on, and we get the car out the door! It took an extra half day, but compared to some jobs, I'd have to say it went fairly smoothly.


The shifter location is nice, but its a pretty long throw ... in time I might put on a shorter arm.

That's about it. I've been through the gears a few times, it shifts much much smoother than the old toploader, the clutch feels good. Time to get a few miles on it.

Phil
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Jul 26, 2012
#2
  • Jul 26, 2012
  • #2
NICE! What gear do you have in the rear of the car?
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 27, 2012
#3
  • Jul 27, 2012
  • #3
Hi,
Your write-up is a great service to those following in your footsteps for the later mustangs. I did a similar "write-up"applicable to the early gen cars. The differences are, after researching both Keisler and Modern I chose Modern's T5Z. I converted from a C4 and had virtually no issues. Well, I did have to remove one of the TRI-Ys. Didn't even have to change my drive-shaft. I'm very glad I made the change. The combination of the .63 5th and my 3.55 rear is a good mix. My 70mph cruise is now just under 2K vs 3k RPMs with the C4 and the 3.55.
Happy Motoring!
 

The_Dude

Member
Aug 17, 2004
137
4
19
Western Oregon
Jul 27, 2012
#4
  • Jul 27, 2012
  • #4
Yeah. A T5 is a much easier conversion (no cutting, or drilling), but I wouldn't put one behind a big block. Nice write up. Thanks.
 
P

PhilJustPhil

Member
May 28, 2002
36
1
8
Ottawa
Jul 27, 2012
#5
  • Jul 27, 2012
  • #5
woodsnake said:
NICE! What gear do you have in the rear of the car?
Click to expand...

3.25 Rear.

The lower 1st in the new transmission was pretty obvious, and a nice improvement.
 
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