Engine and Transmission Tech

This is what my motor mounts look like.


So I set my RV8 / T5 in place with the engine sitting comfortable on the mounts. When I crawled beneath the car and raised the T5 to attach the trans cross member, the car began to rise with an inch gap still between the cross member and the frame rails. I went back to the motor mounts and placed my finger behind the frame slot to see where the bolts were in the slots. They were both at the very top. Simple next step is to just flip them around so the bolt is in the lower position but I doubt this will actually lower the motor in the frame. My guess is my T5 is contacting my tunnel.....

Looking for commentary from the Gallery.
Gary

FWIW, this is how my motor mounts came to me. I have not trial fitted the engine / trans as of yet...

Anybody familiar with these mounts, should the bolt be high or flipped around to the low position for the RV8 with Ford T5 combo?

Also, what is the proper longitudinal position and how is it measured? In other words, with the engine on the mounts, and the cross member bolted to the T5, at what point is the transmission sufficiently raised? Shims can be used between the cross member and the frame but how many?

Quote:

....and raised the T5 to attach the trans cross member, the car began to rise....

The first question to ask is whether you have 'relieved' the sheetmetal at tunnel/cowl interface (point "A" in another thread) - if you haven't, the xsmn will raise the chassis as you have seen....about 3/8" relief is required..
Stud up or stud down makes no difference to engine position - it just impacts the stud location in the frameside engine mount slot - accessability to instal the mount nut is probably better with stud down.
Final engine xsmn position (driveline angle) is dictated by RA pinion angle - they need to be the same. If the RA pinion is set at 3 degrees, then you need to shim the xsmn mount to achieve the same 3 degrees.

ahhhhh, dimensions, numbers useful data I can work with. Very helpful.
Thanks Graham.

So, I did the relief slowly in increments until I finally had sufficient clearance. I began by locating the contact point in the tunnel. I positioned a ~3' piece of #10 single strand insulated electric wire over the top of the T5. I then pulled it back and forth while moving it forward until it would go no further. I removed the engine/T5 and ground out Graham's 3/8" at that tunnel point. I then put masking tape on the tunnel and on the top of the T5 and put them back in the car. Used a floor jack to raise the T5 to the point of contact. Measured the gap between the cross member tabs and frame. I had made progress but still had a ~1/2" gap. Removed the engine and found the contact marks on the tape and ground another 1/8" further massaging with my BFH and stuck the engine back in. Did this all one more time and everything is now where it should be.

Thanks to Graham for the specifics and to Curtis for providing this great website - donation to follow!