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StevenD57
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I visited my fabricator's shop this afternoon and he is very close to having the Toyota Supra W58 5-speed transmission and Lotus Excel bellhousing assembly ready to go. This is using the stock JH flywheel with a Toyota Celica clutch assembly and the W58 transmission out of a Toyota Supra. The fabricator was working on altering the Lotus Excel bellhousing to work with the mechanical clutch cable system from the Jensen-Healey as well as getting the smaller diameter of the input shaft of the Toyota transmission to mate up with the back end of the Lotus 907 crank shaft.

Once I confirm that all of this works I will be looking into the costs of having more of these bellhousings cast up as new replacement pieces so others can do the same conversion.

Once I get all the bits back from my fabricator, I will post some photos.
--
Steven DuChene

Last edited on 05-09-2012 04:56 am by StevenD57

frank12873
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This would be an awesome kit for Delta and/or the Club Store to stock. Thanks for planning to share the fruits of your labors with the Club!

StevenD57
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Ultimately the availability of parts like this are dependent on demand. If only one or two or even three people want and are willing to pay for something like this then it is very unlikely to happen. The costs of doing something like this means that the demand has to be more on the order of 10, 15, or even 20 people to make the whole process worth doing. I visited the pattern maker this afternoon and the initial price estimate to make JUST the pattern to make any castings from was not good. I.E. The initial up front costs before a single part is made do not look good. However I will know more in a couple of days.

StevenD57
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It seems the cost of making a pattern to make castings from is too high to make this a smart thing to do for a low production 36 - 38 year old car like the Jensen-Healey. So no new bellhousing castings are going to be forthcoming. I am looking at another possibility that involves modifying the existing 4speed bellhousing.

I am still wondering if there is actually any interest in this if I were to make 6 - 10 modified bellhousings to allow bolting up a five speed transmission like the Toyota W58 or the Ford T9 to the Lotus 907 engine? I think the price on just the bellhousing would be around $550 if I did ten of them at a time. With either transmission there would some additional cost in modifying the flywheel and clutch release mechanism for the Toyota or Ford clutch. However the benefits are MUCH cheaper clutch parts in the future as well as a larger diameter clutch which would be better to support the torque of modified engines like 2.2L conversions.

Last edited on 05-15-2012 04:14 am by StevenD57

Jim Ketcham
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Unfortunately I do not think you can get the volumes to make this economically feasible. I have done 3 W58 conversions, one using the Lotus Excel bell housing (from LotusBits), one using the kit from Conversion Components, and one using just the bell housing from Conversion Components. I found that the Conversion Components bell housing to be far superior to adapting the Lotus Excel bell housing. It has the castings for the manual clutch and is dimensionally correct for input shaft spacing, etc. I also found that having a 21 spline 8.5 iinch clutch plate custom made to be no more expensive (less than $100) than off the shelf clutches. For me the most difficult part was modifying the shifter extension housing to properly line up. It also appears that modifiable shifter housings and linkages are in short supply as they are in demand by many classic car owners doing conversions.
Jim

AJHAWK
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StevenD57,
I just bought a W58 and have been waiting on Lotusbits to get back to me.There seems to be difficulty in getting responses from our friends across the pond,so I'm definitely interested in being able to use my 4spd bellhousing for the conversion! If you can pull that off,count me in on that one!
Thanks, Alan14858

subwoofer
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Hot tip: Mike Taylor's list of priorities is clear.

1. The customer standing in front of him
2. The customer on the phone
3. The email that popped in.

Ring him up, that usually sorts things a lot quicker.

JodyKerr
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Totally understood. I just find that as I get older it gets much harder staying up late enough to call the UK during business hours ;)

Brett Gibson JH5 20497
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Jodie, dont you mean getting up early ??? Brett

Last edited on 05-17-2012 02:03 pm by Brett Gibson JH5 20497

JodyKerr
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Geting up early involves children, getting said children off to schol, and thn work. Doesn't matter how early I get up, my boy always seems to know. :)

Jensenman
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FWIW: the W58 conversion would be a lot simpler without the odd shaped front housing. When I was doing mine, I couldn't help but wonder if it wasn't simpler to use a 4 or 5 speed bellhousing, remove the stock 1st motion housing entirely and make a 1st motion shaft housing which would center the transmission with the bellhousing, then use a ~1/4" thick plate to block off the oil holes etc in the transmission and keep the countershaft from moving forward in the case and redrill the transmission front case for the 4 or 5 speed mount bolt pattern. Yeah, this sounds like an awful lot but it would actually be simpler than casting a whole new bellhousing, because that is very complicated i.e. expensive. I still have my 5 speed bellhousing, I might dig up a W58 and see what I can come up with.

Also, it is easy to modify the Excel B/H to use the J-H clutch fork etc, I did it on mine. I thought about using a custom clutch disc with the stock pressure plate and release bearing but used the Celica disc, PP and release bearing so I could easily find replacement parts if needed.

A Ford T9 from a XR4Ti should also be a reasonably simple swap on the 4/5 speed B/H, as would the T5 5 speed which was used in a whole bunch of 4 cylinder Mustangs through 1993. It looks a lot like the V8 unit but has 4 cylinder friendly gear ratios and since it's not in high demand is a lot cheaper than the V8 version.

The W58 pilot bearing is an oddball; I do not recall the exact dimensions but after a LOT of hunting and head scratching I finally turned a pilot bushing from Oilite (sintered bronze bushing material). Pilot bushings were made that way for a heckuva long time before needle bearings became popular.

Last edited on 05-20-2012 09:24 pm by Jensenman



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