Getting trans plate to align with rear engine mounts

#1
I wanted to test fit the transaxle plate to the rear engine mounts before I secure the plate on the engine and it does not seem to fit.

That is, the holes where the 1/2” bolts through the rear engine brackets are about 1/8”-1/4” too narrow. See the pics below..

Left Side with bolt inserted into trans plate and bracket...
D23E6F48-27EB-4D58-AA03-95AB6446C591.jpeg


Right side showing the amount of miss alignment of the bracket to the trans plate....
F05EAF37-295C-4C3B-92B5-FD76EFC973F3.jpeg


Wondering the best way to adjust things, this is the first part I am fitting so my guess there is more of getting things to fit ahead of me but wanted to get some advice. I am thinking option #1 below is the best approach.

1)Elongate the 1/2” hole in each bracket equally so the bolts can be inserted straight in
2)Elongate the 3 side holes in each bracket so they must higher and become more spread out and align with the trans plate.
3)Elongate the holes in the transplate.
4)Ask for new brackets that align correctly

Thanks for the help!
 

Ian Anderson

Member
Lifetime Supporter
#5
I would first look at how central the box will end up in the chassis.
You may want to move it one way or the other so make sure you make the adjustment on the correct mount, or you may actually need to adjust both!

Ian
 

Steven Lobel

Member
GT40s Supporter
#6
Mount to engine loosely, flip the mounts on the frame, loosen the mounts on the frame. It took me 20 min to wiggle things and flip the metal over and around before everything lined up. I did not need to redrill, just figure out the puzzle. Hope this works for you.
 
#7
Mount to engine loosely, flip the mounts on the frame, loosen the mounts on the frame. It took me 20 min to wiggle things and flip the metal over and around before everything lined up. I did not need to redrill, just figure out the puzzle. Hope this works for you.
Thanks Steve,

I am not at the point to mount the trans plate on the engine, but this is what the brackets look like without them being tightened. You can see when one is flat the other has a angle to it show the holes are not wide enough. If I tighten all this up just not sure if that is the right thing to do. Concerned it will push the frame out or warp the trans plate. But maybe by tightening it up the mount plates give and line up properly, just not sure.

Did yours look like this before you tightened them?

0AEADDFA-0869-4E37-96D3-062D2731CF56.jpeg
 
#9
It might end up being a lot of work but you could mate your engine and trans, drop the whole thing in and secure the front via the engine mounts and the rear via the ears on your trans. Get it all lined up and level, then position those 2 plates to see which are out, and where. Modify the plates accordingly.
 
#10
It looks like the passenger side mount is pretty bent out of shape
Alex, the brackets are not bent. It’s just one side is flat and because the holes in the trans plate push the bracket out the other is on an angle. That is why if I went to tighten it, something needs to bend. Not really sure what, so hesitant to start putting a wrench to this. I’ll speak to RCR next week and see what they say,
 
#11
Joel you mentioned that your front engine mount was too short. Do you have the lower U shaped brackets in place as shown in the picture I posted or is the problem the fact you can't install the u shaped brackets?
IMG_2416.JPG
 
#12
Hi Ken,

It’s the latter. The mount hugs the outside edges of the frame rails and there is no room for the U-shapes brackets. Actually the mount really doesn’t clear the outside edge of the frame rail without some force so clearly too narrow.

Here are some pics...
Left Side inner frame rail edge...
8B49E6AA-0949-4767-9B89-9D6073F8B5A2.jpeg


Left Side outer frame rail edge...
C1805CF4-27BE-4498-8FA4-9C01DF30284A.jpeg


Right Side inner frame rail edge...
4C5A5241-C2DF-4CBC-8400-9155B687DCD5.jpeg


Right Side outer frame rail edge...
1B886556-A757-4134-AAD1-9BA9459493F6.jpeg
 

Johan

Member
GT40s Supporter
#13
Joel, to me it lookes like your lower frame rail is mounted/welded too far apart, since both front and aft motor mounts are too narrow.
During the day I’ll measure mine so you can compare the distance.
 

Steven Lobel

Member
GT40s Supporter
#14
Mine was similar. Put it all together loosely and tighten by going a little bit at a time side to side and front to back. I will check to see if I used any washers in the gaps for the crossmember mount.
 
#16
Joel, mine measures 626 mm inside/inside the beams both front and aft. My mounts was a perfect fit.
Thanks Johan,

My rear rails are 29” outside edge to outside edge, and 25”(635mm) inside edge to inside the edge so 10mm wider than yours. The U channels are 1/8” thick so the engine mount looks like it needs to be about 1/4” wider.

I have a note in Kristin and will follow up.
 
#17
Mine was similar. Put it all together loosely and tighten by going a little bit at a time side to side and front to back. I will check to see if I used any washers in the gaps for the crossmember mount.
Thanks for your help Steve, if you used washers then the rear engine mounts on yours lined up with room to spare, where in my case if I tighten them it will push the mounts against the frame rails since there is not enough room.

Since the front mount fitment needs to be addressed, I have to figure that out before I start tightening up those rear mounts. But my sense at this point is to not proceed and tighten it up the way it is, just looks too far off to start applying pressure.
 

Dan Carter

Member
GT40s Supporter
#18
Joel

If your using an LS3 and haven’t checked the two verticals mating to the engine mounts, you might want to. I had some issues with mine, albeit small, they were off a tad.
 
#19
Joel

If your using an LS3 and haven’t checked the two verticals mating to the engine mounts, you might want to. I had some issues with mine, albeit small, they were off a tad.
Thanks Dan, using an LT4 and haven’t gotten there yet but good to know I need to check.
 
#20
Joel, just my $.02 but I'd be tempted to split the difference/mis-alignment on bot the bracket and on the plate. Of course, I have a lathe and milling machine and all the necessary bits and fittings to do that which makes it relatively easy. Alternatively, as Neil said, if you have the room/set-back for the fastener head then you can simply plug weld and re-drill too. Personally, I sort of like a bit of a slot instead.....so I can accommodate some lateral positioning if needed.
 
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