Slotting Engine Mount Pedestal Holes - Anyone done it?

MJ, At the moment, I've got each mount in it's proper location...holes are biased to the front.  Another idea was to intentionally swap the pedestals left to right, then drill new mounting holes.  Something to think about...

If you look carefully at the previous photo, you can see that the rearmost rubber bushing had been modified, the ZF mounting ear was in hard contact with the saddle on the frame...no isolation.

On the RH side, all was well:

No damage that I can ascertain.

From what I understand, this LH ZF mount is a recurring issue with these cars.
So much so, that some vendors (Quella, etc.) have modified the saddle by cutting off the rearmost ear and moving backward 1/4" before re-welding it to the chassis.

I'm not in a position to do that at the moment...

Thanks MJ.

Any other opinions?  I'm all ears...

The later 9000 series cars had a removable saddle for the ZF, it makes install and removal a breeze.

I actually modified 2511 during the collision repairs to incorporate the 9000 series removable engine mount. I can state that removal and installation is much easier with this style of mount

Unfortunately, neither cutting and welding, nor the removable mounts are an option right now...I just finished painting and detailing the entire engine compartment:

The steel transmission mounts can be bent into an “S” with a suitably large wrench.  I used this technique to move my transaxle rearward 1/4” to fit a big block Ford engine.  It is low tech, but perhaps it will save you from cutting and welding in your beautifully painted engine bay.

Can you mill some material off the back face of the offending transmission mount?

I don’t think it would weaken it, as long as you maintain the structure where it mounts to the ZF.

You would have to push it out the rubber bushing before machining and then perhaps shorten it up a little bit prior to reinstall.

Rocky

@bigblockfan posted:

The steel transmission mounts can be bent into an “S” with a suitably large wrench.  I used this technique to move my transaxle rearward 1/4” to fit a big block Ford engine.  It is low tech, but perhaps it will save you from cutting and welding in your beautifully painted engine bay.

Hi BBF,

Nice car!  Thanks for the suggestion, I'll look at it closely today...

@rocky posted:

Can you mill some material off the back face of the offending transmission mount?

 

Rocky

 

Hi Rocky,

I'll also investigate this solution.  Maybe a bit of milling on the mount, combined with bending that saddle ear slightly will get me where I need to be...

Bending the steel ZF frame-ear(s) is by far the quickest, least invasive and most simple way to tweek the powertrain mounting position: no welders, drilling, cutting etc.  Incidentally, the rubber lip in the rear of the mount bushings is only there to prevent squeeks; if you have none, there's really no problem with leaving things as they are. Ear welding on the subframe was not micro-precise in Italy.

IMHO, most owners are interested in moving things backward for clearance. Shifting the powertrain forward very far risks driving the distributor cap and water pump pulley into the firewall or the steel access door. Adding to this thread, it's far easier to fiddle with the aluminum ZF mounts and the tranny itself if you remove the three studs holding each casting to the ZF and replace them with proper length metric bolts. In this case, the protruding studs are more difficult to work around than bolts, even though the threads go into an aluminum gear case.

Hi Guys,

Thanks for all of the suggestions.  It was a combination of modifications that got the engine-transmission unit in place, and fitting well:

1.  I bent the rear saddle ear a bit, that gained 1/16"
2.  I shaved a bit of material from the LH rear ZF bushing, that gained 1/16"
3.  I slotted the pedestal hole (LH side only) by 1/16"

Everything dropped into place easily, and all bolts installed into their respective locations easily...no hammers or pry bars required.  ;-)

Still plenty of distributor cap clearance:

Looks very nice!  Congrats!

@rocky posted:

Looks very nice!  Congrats!

Thanks Rocky!

Now to attend to the details of getting it running in the car.
It's been previously tested on my engine run-in stand:

Very nice to see the run test. Very professional set up. Spent yesterday night  fitting a similar set of extractors into my car- - very very tight on the LHS. They are in . Barely in.

I am looking at increasing the final pipe run diameter to the rear resonators which is currently 2 inch. 

The front flange on your extractors looks 3 1/2 inch - what do you reduce down to for the rear pipe run - 2 1/2'" or 3" ? 

Any trouble threading that through to the rear without clobbering the drive shafts? Do you know what the maximum diameter you can reasonably squeeze through is ?

Hi Percy,

The pipes in the video are for the test stand only.  The exhaust on my car is currently 2-1/2" diameter, but I'm going to try to cram 3" exhaust thru the suspension over the winter.

I did the CV axle upgrade last year to open up a bit more room for the larger exhaust...

@marlinjack posted:

...For what it's worth...I have 2-1/4" Pipes, on a Good Bounce/Jounce, they will rub against the Short Shaft, on one side of this car. I wanted to go with 2-1/2", the Pro Installer said He couldn't fit it in, to Clear. 3"?...Good Luck. MJ 

Marlin, I've personally seen it done (3" exhaust pipes) on a buddies Pantera, so I know it's possible.
My current 2-1/2" exhaust clears everything by at least 1/2", so I should be OK.

I already have a lovely 1/2 " depression that has developed very nicely on the top of the LHS side pipe under the short shaft which has now cracked clean though. 

The current pipes  are exhausted ( sorry )   .......and hence my question.  Can you recall if your friends car with the 3 inch exhaust used formed pipe  or was  it fabricated using short radius bends? 

I am looking at it and thinking it may have to be fabricated using  short radius fittings to get the required clearance. If I could get 3" in there the 3 1/2" extractor discharge diameter makes so much more sense. 

I seem to recall somebody some years back fabricated 3 inch exhaust and he used oval tubing to facilitate clearance.

just food for thought

Larry 

I can say 3” exhaust is definitely possible with round tubing.  You could also use round tube to oval tube back to round tube for the tight areas.  Dennis Quella gave me that tip.  If I remember correctly Stainless Headers offers products like that or can make what is needed.

By the way, your engine bay looks very nice Mike.

Thanks Everyone. I have decided to give 3"  a red hot go. Cant be worse than whats there now !

I had a 3" exhaust fabb'ed for my "pushbutton" '71. Tight but definitely doable. As I recall, since I used spherebar mounts for my anti-roll-bar, that raised the bar just enough to dimple my exhaust. Car was lower than stock and with a higher spring rate.

That aside, the only other insight I can offer is the 3" pipes may be louder. I ran mine into 2-chamber Flowmaster race "mufflers". Not recommended for the street. But, mpaschetto, looks like your engine can make use of the added flow!

Dave