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McKinney Engine & Gearbox Mount Alignment Issues?

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I've just spent some length of time trying to figure out the engine/transmission fitment issues I'm having at the moment and have hit a bit of a wall so I'm hoping someone on here can spot where I'm going wrong.


Car is a US spec '71 240z, engine is a BNR34 RB26, transmission is from an R33 GTST (RB25), engine and gearbox mounts are from McKinney Motorsport.


I fitted the McKinney engine mounts to the engine, then the McKinney gearbox poly mount to the gearbox, then bolted the engine & transmission together.


I lowered the whole assembly into the car, and using an engine leveler I got it sitting roughly square and level in the car.


I found though that I couldn't get the engine to clear the bonnet latch bracket.  I thought it must have been something to do with a clearance issue; it kind of felt like the engine needed to go backwards for the mounts to sit on the subframe but it couldn't quite get "under" the bonnet latch bracket as the engine clashed with it.


I struggled with this for a while so tried a different approach.  I unbolted the subrame from the car and lowered the engine down to get the rear of the engine sort of under the bonnet latch bracket.  I then bolted the subrame onto the engine and bolted the gearbox mount to the poly bush.  This seemed to work pretty well as it was much easier to get the engine into roughly the right place.


I then lifted the whole lot back up again so that the gearbox mount lined up perfectly with the bolt holes in the chassis, but somehow the problem with the bonnet latch bracket remained, it STILL clashed with the engine.


I can't seem to figure out what's going wrong here?


You can see from the pictures that the following all seem to be correct:

  • The gearbox is pretty central in the transmission tunnel.
  • The engine is pretty central in the engine bay.
  • The engine mounts are adjusted so that the engine would be in its forward most position.
  • The engine/gearbox mounts all seem to be fitted correctly.
But somehow, the RBs breather still seems to be butted up hard against the latch bracket.  It's odd, because the only way for the engine to clear the bracket would be to either move the engine forward or downward.  I can't see that this is possible though because its position along the length of the car is somewhat fixed by the gearbox mount and it can't really go any further forward anyway without the front pullyeys hitting the anti-roll bar, that means the engine can only really go down and away from it.  However, this isn't possible either.  You can see from the pictures that the engine is fixed to the subframe, but the subrame isn't bolted to the chassis.  This is because it can't come up any higher because of how hard the breather is butted against the bracket.


I've tried everything.  All the bolts are done up finger tight so that the whole assembly can be "jiggled" around to try and get it to line up right but it doesn't.


Can anyone suggest where I may be going wrong? Any help would be much appreciate, I've been really struggling with this for hours!









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Thanks for the info ZT-R.  I've been through 15 pages of your build blog and can't seee any pics of the mods you did to the tranny mount.  Can you pount me in the right direction?  Do you mean the McKinney mount bent or do you mean the mount inside the transmission tunnel bent?

Also, do you know what the correct inclination of the RB should be?


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I don't think i have any pictures of it. The mickenny didn't bend but the leverage put on the stock mounting bolts bent the mounting locations. i took some rectangle tubing and came off my frame rails and went directly in line with the trans mounting bolt rather than what mckinley did. ( i understand why they did it trying to make a bolt on solution) but my r34 gtst trans is really heavy. probably would be fine with a rb20 trans.

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I'm also trying to set the orientation of the engine correctly.  I've found people saying that the engine should be angled over at a bout 10-11 degrees, although I can't find any info on where this angle is being measured from? Does anyone know?

Also, I'm trying to work out the correct angle "nose to tail", my engine seems to sit quite a bit nose up.  Does anyone know what the correct angle should be?



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I think i would start by taking out those washers on the passenger side. My engine 2.70 degrees but you can tweak all these numbers, main thing is driveline angle which you can change on the differential too. For the angle of the engine i just tilted till the bottom of my oil pan was perpendicular to the frame. 

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Exlifesaver, I left the speed sender in place but notched the mount in order to clear it.  You can see it in this short YouTube video I made to explain what I did.



When I next take the engine/transmission out, I'll weld in some plate to tidy it up, then I'll also add some bracing around the mount in the tunnel.

I've looked through so many build threads I can't remember which is which but I think ZT-R one did the notching, with no additional bracing on his build and it was OK?  Maybe look through his build thread.

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