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 Posted: 07-18-2007 12:41 am
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Lash Russell
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    First posting, I thought I'd jump in.  I am at the near end of a conversion from the 4 speed to the 5 speed Getrag.  I installed the new pilot bearing, newly ground flywheel, pressure plate, disc, TO bearing and of course the newly rebuilt Getrag 5 speed.  Having felt very good about the progress I went to support the tranny on the freshly blasted and painted tranny support only to find that the location for the mounting studs needs to be approx 3-5 inches behind those for the four speed.

     Has anybody come across this before?  I'm thinking the studs are some kind of flat head type (I should have looked before I was finished for the evening) that are likely tack welded to the floorboard from the topside.  Does anybody have experience with adding new tranny support studs after this said conversion?  I'll want to leave the original studs for one of those "just-in-case" scenarios where I have the the ability to revert back to the old 4 speed if I need to.  I would have guessed that both 4 and five speed support studs would have been in the same location, oh well!!!!  Any guidance would be greatly appreciated.

Lash Russell

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 Posted: 07-18-2007 02:10 am
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Ron Earp
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Yep, discovered same thing.

Bolted a GM transmission mount in place and bolted the five speed to that. I'll dig some pictures out tomorrow if I can. Left studs for the four speed.

Ron

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 Posted: 07-18-2007 10:31 am
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Lash Russell
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     Thanks Ron, why did you need a different mount, was the GM one better or more available?  Is there a GM part # (I'm looking forward to the picture).  Did you drill and weld new studs in or drill holes and bolt the crossmember in?

Last edited on 07-18-2007 10:53 am by Lash Russell

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 Posted: 07-18-2007 12:35 pm
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Ron Earp
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GM mount bolted right up to the other half of the five speed mount, it is super strong, and it is very cheap and available everywhere. I've got to get my old computer fired up to see what pictures might be there. There are a bunch of images here:

http://www.gt40s.com/images/jensen/

There *might* be a transmission shot in there, not sure.

Ron

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 Posted: 07-20-2007 02:49 am
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pbahr
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Lash,

Sure, the 5spd pattern is about 4 inches away from the 4spd bolts.  I did this three years ago, and just added bolts in the correct positon - was not a real problem.  Ron seems to have an easier solution than drilling new holes...........

Don't forget the other issues:
  1. New Speedo/Odometer cable.
  2. Add the rubber isolator, Jensen p/n 97582, Insulator - gearshift mounting.  You'll have to drill a hole in the Tunnel and bend sheet metal a bit.
  3. Single piece Driveshaft.
  4. Correct ratio Differential.
  5. Check the complete Shifter mechanism for slop.  There should be NO slop.  If there is, you will be very sorry when you start shifting, and miss a few gears...........
YELODOG

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 Posted: 07-21-2007 12:41 am
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Lash Russell
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Hi Ron,

     Went through your entire portfolio of phots, kudos to you man, you have done a very impressive job with your race car!!!!  Can't even imagine the amount of work you have put into this. 

     Looking at the one picture you have of the rear view of the transmission installed in the car it looks like the original setup.  A couple of questions regarding the mounting:

1)  When you mention the GM mount, do you mean the rubber isolator mount itself?  If so, I'm guessing this GM mount is very similar dimensionally to the original Jensen Healey part and bolts directly to both the transmission bracket and the crossmember, is this correct? 

3)  Also, I believe there are several GM tranny mounts through the years, do you know what car / model / year it came from or the GM / Chev / Pontiac, etc part no.?

4)  Did you use the original Jensen crossmember?  If so, how did you attach the new studs for mounting further back?

     Sorry for all the questions, thanks in advance.  I'm just trying to figure this all out.

Lash

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 Posted: 07-21-2007 12:45 am
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Lash Russell
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Hi Pete,

     Thanks for the reply, I've looked at your collection of JH upgrades and I may need to take you up on some of these. 

Thanks, Lash

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 Posted: 07-22-2007 11:41 am
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Ron Earp
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Hi Lash,

Thanks for the kudos, now if I can get energized to repair it.  The pictures that have the original mount are probably old pictures with the car with the four speed. I looked through everything I have and don't have anything with the new GM mount and the five speed. I have to go to the storage shed where the Jensen is parked after the explosion and I'll get some pictures. It was a GM TH400 mount if I recall, so very common, but I will verify this for you and try and get a part number.  It came from Summit as I recall, was an upgrade mount for certain cars and was cheap.

Best,
Ron



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