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Thealien · 12-21-2009, 03:16 PM

Motor mounts and adapter plates

A couple of drawings of adapter plates, you would need two of either plate. This one would move the engine forward some.

They are showing the wrong hole countersunk. The hole that should be countersunk is the one between the two 1.75 inch measurements. The point goes forward and to the top. You have to countersink the hole that ends up behind the motor mount. The two plates will be mirror images with the countersunk hole on opposite sides of the plate. This is more like most of the aftermarket adapter plates. Most of them are 5/16-3/8 while these are 1/4 inch. The slight thickness differences could change engine height. I haven't read much about anyone having any issues with any of the different thickness adapter plates.

Scroll down

S&P
multi position adapter plates

MULTI POSITION
Moroso scroll down

MOROSO
Year one

YEAR ONE
Car Shop

Car Shop
And advance adapters. They are the only one that doesn't use the bottom bolt hole to position the motor mount? Hmmm

Advance Adapters

Now the drawings say 1/4 inch and all the rest are 5/16-3/8 which in my humble opinion will slightly change where your engine sits, higher/lower?

There are some issues with crossmembers on the 4X4 trucks causing motor mount and crossmember problems. My truck is stock height so these won't work for me but 4" plus lifted vehicles can use these from Pacific Fabrication
Pacific Fabrication

12-21-2009, 03:16 PM	#3
Thealien Senior Member Join Date: Jun 2007 Location: Pine Ridge Florida Posts: 4,126	Re: LS engine swap info Motor mounts and adapter plates A couple of drawings of adapter plates, you would need two of either plate. This one would move the engine forward some. They are showing the wrong hole countersunk. The hole that should be countersunk is the one between the two 1.75 inch measurements. The point goes forward and to the top. You have to countersink the hole that ends up behind the motor mount. The two plates will be mirror images with the countersunk hole on opposite sides of the plate. This is more like most of the aftermarket adapter plates. Most of them are 5/16-3/8 while these are 1/4 inch. The slight thickness differences could change engine height. I haven't read much about anyone having any issues with any of the different thickness adapter plates. Scroll down S&P multi position adapter plates MULTI POSITION Moroso scroll down MOROSO Year one YEAR ONE Car Shop Car Shop And advance adapters. They are the only one that doesn't use the bottom bolt hole to position the motor mount? Hmmm Advance Adapters Now the drawings say 1/4 inch and all the rest are 5/16-3/8 which in my humble opinion will slightly change where your engine sits, higher/lower? There are some issues with crossmembers on the 4X4 trucks causing motor mount and crossmember problems. My truck is stock height so these won't work for me but 4" plus lifted vehicles can use these from Pacific Fabrication Pacific Fabrication Last edited by augie; 04-19-2011 at 11:31 PM.