My Voigt 5-speed conversion

[1owner69Elan]

Another minor improvement to the Voigt kit. Steve reported difficulties in fitting the reverse switch wires as the connectors stick out too far. He fashioned some L-shaped connectors to allow more clearance.

I also created some using Lucas bullet connectors. I found the female connector to be nice and secure on the switch. Simply removed the outer sleeve to expose the metal cylinder inside. Bent it 90 degrees at the existing mid-point half cut. Inserted male bulleted wires and shrink wrapped the whole thing:

I shared this with Alan Voigt. He admitted they have been looking for a better connector than what they now supply.

[alan.barker]

Is the angle of the input flange on Diff the same as output on Gearbox. They don't need to be the same height but need to be the same angle.
Alan

[1owner69Elan]

Is the angle of the input flange on Diff the same as output on Gearbox. They don't need to be the same height but need to be the same angle.
Alan

I won't be able to check the actual angles on the diff and gearbox until I get the engine in and also presumably check at ride height.

In setting up my gearbox bracket spacers I have assumed (for now) that Voigts had it right with their supplied bracket and spacer. All I have done is to put the gearbox in the same position for the two different brackets. If the Voigt bracket is wrong, my bracket will also be wrong (by the same amount).

But, as I said, one can fine tune this to set the proper angles for the gearbox and diff. I never checked the gearbox and pinion angles on the standard factory setup. I wonder how close they are (were). Though I never experienced driveline vibrations or rapid wear of u-joints. Front u-joint finally did fail after about 45 years.

Prior to teardown I did measure the engine/gearbox at 4.05 to 4.15 degrees down (front to back). But, I didn't measure the diff angle.

I also ran into another issue. The TTR uprated propshaft comes with grease fittings for the front and back ujoints. The original propshaft ujoints had no fittings (zerks). I'm wondering since I am changing out the yoke (for the T9) anyway on the front ujoint whether I should put in a non-zerk, sealed version, since I am not going to be able to reach it anyway to grease it (maybe by removing the seat and accessing it through the large tunnel hole?). I'll probably never go through that effort. So, a sealed ujoint might make sense. Also, with the low mileage utilization of the car, the lifetime of the sealed version is going to be as long as is meaningful for me.

[steve lyle]

A quick update on road experiences.

I've put about 400 miles on the car since the upgrade.

There's no discernible driveline vibration - and I never bothered measuring any angles on anything, just went with the stock kit and hoped. So no issues there.

I sent the parts back to Alan about the middle of June. According to the USPS tracking site, they landed in Heathrow on the 20th. And have been "out for delivery" ever since. Apparently, USPS is >>>> Royal Mail. At least in this data point.

I've got no problem with the shifter. I know quantitively it's longer than stock, but at this point I don't have any memory of stock, it just strikes me as "fine".

Alan offered a reasonable reimbursement for the extra work involved for my upgrade, which I gratefully accepted.

75 mph is right at 3500 rpm. 65 is 3000, 55 is 2500. Which is handy to know, because my speedo, which used to be spot-on, now reads high by quite a bit.

A lot of our secondary roads are posted at 45, I've found myself shifting from 3rd directly to 5th, and just burbling along at times.

[1owner69Elan]

Good to hear your road report and all is well.

Regarding the angles issue, I realize that when I recently rebuilt the car, changing the prop shaft, I also put new bushings and mounts all round for the diff (from TTR). It seems the diff has more clearance now to the lower rail than before. But, I never bothered to measure any angles. Car was fine at all rpms. I guess for peace of mind I'll check the angles when I get things assembled.

[My72Sprint]

I’m considering a Voigt 5 speed upgrade but like 1owner69Elan I have a TTR exhaust and with have clearance issues.

What in the height on the provided Voigt spacer installed between Transmission mount and flat plate?

I’m considering a milled a rear mount from a block/sheet of 6061 T6 aluminum.
Gives you clearance and based on shear/ hardness /strength 1/8” or 3/16 final thickened should be enough.

Way overkill but light & would look cool.
No clue about $’s yet. I'll need to create a version in wood first.
Tim

[bill308]

Hi Guys,

I worked the exhaust clearance issue on my Voights install, posted here:

viewtopic.php?f=31&t=37259&start=30

In the end, I designed and fabricated a special bridge mount, that allows the large bore exhaust tubing to be positioned, within about 0.5 inch of the backbone sheet metal. The other key decision was to remove the bottom cast lug and scallop out a bit of extra material, from the cast aluminum, Quaife, trans case. I think road clearance will be quite good. Should enable a wide range of ride height, maybe settings for road/load, or track work

Bill

[1owner69Elan]

I’m considering a Voigt 5 speed upgrade but like 1owner69Elan I have a TTR exhaust and with have clearance issues.

What in the height on the provided Voigt spacer installed between Transmission mount and flat plate?

I’m considering a milled a rear mount from a block/sheet of 6061 T6 aluminum.
Gives you clearance and based on shear/ hardness /strength 1/8” or 3/16 final thickened should be enough.

Way overkill but light & would look cool.
No clue about $’s yet. I'll need to create a version in wood first.
Tim

The height of the Voigt aluminum spacer is 3/4 inch.

One thing to realize is that the modification that I made only increased the clearance for the exhaust by ~3/4" which is the thickness of the Voigt plate (1/8") plus the plate fold-down. If you fabricate a different bracket to increase this clearance further it will require the central span of the bracket to be less thick than the folded metal one.

I would be interested to see what you come up with for a more "elegant" bracket.

[1owner69Elan]

Hi Guys,

I worked the exhaust clearance issue on my Voights install, posted here:

viewtopic.php?f=31&t=37259&start=30

In the end, I designed and fabricated a special bridge mount, that allows the large bore exhaust tubing to be positioned, within about 0.5 inch of the backbone sheet metal. The other key decision was to remove the bottom cast lug and scallop out a bit of extra material, from the cast aluminum, Quaife, trans case. I think road clearance will be quite good. Should enable a wide range of ride height, maybe settings for road/load, or track work

Bill

It appears that the casting lug may be a bit smaller now on the later Voigt adapter.

But, your post reminded me that this lug also needs to be navigated by the exhaust system. I believe I am still OK as the current smaller lug appears to be high enough to not restrict clearance and my exhaust configuration, I believe, has more clearance at the point where the lug is. But I haven't yet fitted the exhaust with the gearbox installed. Fingers crossed.

[bill308]

Hi 1owner69elan,

I just saw your second post. I think the following might still be useful

Page 3 of my thread has a number of photos, one of which (farther down the page) clearly compares the differences between the OE, Voights, and my transmission support. My in-between height bridge features a thin, but boxed cross section, in the center channel. This design, as the others, benefits from the stiff, lower, steel section of the OE rubber motor mount, to which it is rigidly bolted. I think I have a dimensioned drawing or sketch somewhere, if interested. Check out the photos in the thread. I can take additional photos.

Concerning the alignment of the transmission and rear end drive flanges, remember the hooks joints at either end are meant to accommodate misalignment. Under load, both ends probably move around several degrees, whether accelerating, or trailing throttle. Get the alignment close and I think you are good to go.

Bill

[1owner69Elan]

Hi 1owner69elan,

I just saw your second post. I think the following might still be useful

Page 3 of my thread has a number of photos, one of which (farther down the page) clearly compares the differences between the OE, Voights, and my transmission support. My in-between height bridge features a thin, but boxed cross section, in the center channel. This design, as the others, benefits from the stiff, lower, steel section of the OE rubber motor mount, to which it is rigidly bolted. I think I have a dimensioned drawing or sketch somewhere, if interested. Check out the photos in the thread. I can take additional photos.

Concerning the alignment of the transmission and rear end drive flanges, remember the hooks joints at either end are meant to accommodate misalignment. Under load, both ends probably move around several degrees, whether accelerating, or trailing throttle. Get the alignment close and I think you are good to go.

Bill

Bill,

Your bracket design does indeed provide more clearance than my quick fix. In fact, your whole exhaust setup, as far as ground clearance, is much better than mine was before as well as will be after the Voigt installation. The only real problem I have with clearance now is the TTR Race Systems muffler (silencer) that hangs down quite low in the back. It does scrape from time to time. I have a smaller, ultralight muffler from Pro-Fabrications (formerly Coast Fab, also marketed by Burns) that should give me more clearance. But, it undoubtedly is going to be louder. Whether that is acceptable remains to be seen.

[1owner69Elan]

Hi 1owner69elan,
Concerning the alignment of the transmission and rear end drive flanges, remember the hooks joints at either end are meant to accommodate misalignment. Under load, both ends probably move around several degrees, whether accelerating, or trailing throttle. Get the alignment close and I think you are good to go.

Bill

Just got off the phone with Dave Vegher. He tells me he never really worried about getting the pinion angle and gearbox alignment just right. He says you can play with it a bit, easiest by shimming the gearbox mount, but don't sweat it.

As I have said before Dave is now retired but still actively working on cars. Has an Alfa GTV project that he has underway and is also building a hot Alfa street engine for Bobby Rahal (Indy winner etc....). Dave started out more than 40 years ago with Alfas before moving into Lotus and others.

Dave's shop (Veloce Motors) before retirement:

[bill308]

I found my tranny mount sketches. Originals are in a PowerPoint file.

Dimensions are from my measurements. The mild steel rectangular tube, outside dimensions, are 1 x 3 inches

Dave Vegher retired? One of the best twin cam builders. Knowledgeable and willing to share. Stay healthy Dave.

What kind of muffler are you running?

Bill

[1owner69Elan]

Bill, thanks for the drawings. Very useful. I may adopt your design downstream depending on how things go.

I am currently running the TTR Race Systems silencer (S4/Sprint), TTR-EX-008. As I noted this does drag occasionally in the back.

I'm going to try the smaller Pro-Fabrication (ex Coast Fab, Burns) ultra-light muffler but fear it may be too loud. Here is a picture of the muffler (being held by Dave Vegher).

Dave recommended these and had used them on various race cars. With the current racetrack sound restrictions, not sure whether these were (are) sufficient to pass muster.

Jay Leno does use this muffler on his street "26r". From the videos (https://www.youtube.com/watch?v=UbMcV-LdHuw ) it doesn't seem to be horribly loud (but it's certainly not quiet). But, it may be that he is using a larger diameter version than what I have.

I'll probably wait to work on the exhaust after the 5-speed installation is sorted out. Don't want to change too many things at once.

[bill308]

My light weight TTR body has the large, inline muffler cavity option, so can accommodate the larger case, probably with enough clearance for some insulation (Aerogel product), or at least a stainless radiation shield, with an air gap. This larger cavity reduces the boot volume such that the TTR gas tank is a little shorter for my car. Not too difficult to make a larger muffler cavity.

What is your exhaust diameter? I think I'm 1.25 inch OD.

Do you have as much of an interference at the T9 case peg, as I did?

Bill