Finally getting ready to send my '71 I've had since new to the restoration boys at Stalltek for paint and six conversion work.
I've never figured out the search function so would like opinions on the best bulkhead engine mount options- want a factory look and will be doing a mild 2.4 E engine build. The car has already been converted to a side shifter some 30 years ago... getting the sheet metal I got here on a group buy powdercoated as we speak.

Have at it guys...

A smaller engine like yours, defiantly get the original equipment.
Matt

Agreed
You want the right original look
Stock or reproduction of stock

Oooh Stalltek. Looking forward to updates through the process.

Only thing I have to share is Congratulations

My pick for best one.

I would agree with the above if you are staying with a small six. But you need to consider that you may want a bigger engine in the future. If you do, you want the stronger motor mount.

The Naroescape mount is really good, as is the Rich Johnson mount.

I’ll be using the maddog oem replica for a built 3.4 engine. I’ve already seen it in place on a hot 3.0 (300 hp on a Peter Dawe built engine) I tried the Naroescape mount. No bueno. Eventually I will remove it from my car and make the tin and everything fit properly bum not the first one to have problems with that mount but it sure was frustrating.

Stronger is sort of a relative term. Has the oem mount proven to be inadequate for big engines or is that just your perception. I have seen big engines in real sixes without issues. Some of them get flogged pretty hard on the track.
The nice thing about an oem style mount is everything fits the way it should.

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Translation: the engine doesn’t fit right . . . But that’s normal.

The OEM mount also locates on the bulkhead where there is internal structure to support it rather than just hanging off a layer of sheetmetal that is unsupported. NVH will be better with the OEM mount and OEM rubber isolation (i.e. less in cabin noise and vibration ) Nice that the OEM rubber isolation is now being reproduced.

I do not like the fact that the front of the motor is only supported by one point for high power/high torque applications. In the 911, there is a wide spaced mount.

The Rich Johnson mount handles the high horsepower/high torque better than a stock 914-6 mount.

Keep in mind OP is running a 2.4L

High HP brings along all sorts of other problems besides engine mounting.

Not only does the engine tin gap about an inch but it barely cleared the shift rod and affected some of the hard brake lines. It might work for some people, not me.

agree with Matt, get the original setup, we get them from germany, quite close to the original factory setup and will work GREAT for your application

What is the difference between the 2 MD mount options?

I used the MD mount and really like it. Installed easy, replicates the factory mount.

One is a copy of an RJ mount, that was a copy of another mount. Uses two 911 engine mounts. The other is a copy of the Porsche OEM mount. Uses one large oem 914-6 mount.
The oem style fits the best (in my opinion) and needs the least amount of adaptation of lines, tin, shift rods, etc. Porsche did a good job on the design.

Just for some tight numbers onthe Naro mount; if you locate it where they indicate the motor is 0.85" low - this can be rectified by welding the mount upward by 0.85".

The other issue is that the Naro mount puts the engine 0.5" closer to the firewall so you would need to space off the mounts 0.5" from the firewall.

The Patrick mount has offsets too that I have measured that are similar, but not exactly the same - If someone wants those I could dig them up (it's all in CAD).

Yes, I had the space from firewall issue as well. Had to weld up some stock to make it work.

And . . . We are right back to the discussion in the other recent thread about having to modify aftermarket parts to fit and do the intended job

Yea, there’s that. In this case, it’s not a replica of an original part. It’s supposed to be something better or at least a quality alternative. I didn’t find that to be the case. YRMV.


One thing I would be curious is how much torque is on the engine mounts and how strong do they have to be? I haven’t heard of any bulkhead mounts failing under any circumstances. Not to say I have superior knowledge or experience with the mounts. I’m just wondering how much strength is needed and does a big engine need a different mount from a small engine.
I think I remember someone noting that both factory 914-8’s use a stock style mount. If that’s true, that gives us an idea what Porsche thought about the issue.

As I said in my original post, the factory style mount is fine for a 2.4L engine.

I am not comfortable with that style of mount with a very high horsepower/high torque application.

But it is MY opinion.

Just keep in mind that doesn’t come with the actual rubber mount. my website shows everything wrapped up together so it’s a complete setup. I prefer the OEM mount only because it allows everything stock to fit well including shift linkage and heat exchangers. It’s the KISS method. Not sure it’s the right answer for anything over a 3.2 in my opinion

I never liked aftermarket mounts because they all required compromise of some sort.
To remedy this I fabricated a duplicate of the original bulkhead piece and located the
OEM parts to complete the set.
A repro of the original rubber part is now available.
If I had to do it again I'd get as close as possible to the original design using the copy
available but would re-inforce it much like the factory did

I am not sure where I heard this, but it is my understanding the factory six mount is not just welded to the outer firewall panel; I believe that is double-walled. But I guess we will find out how strong the stock 6 mount is; I still use my stock 6 mount and now have the 3.6 in my car. Granted, I only have about 200 miles on it so far, but time will tell if it holds up. (fingers crossed).

PS- I did have a MadDog mount (HB offered his up) we could have installed but I decided against it.

Correct

There is a hat shape channel reinforcement that connects the inner bulkhead to the outer bulkhead in the factory mount location. This adds a lot of strength and stiffness to the factory mounting area.

The Nano and PMS style mounts are supported by nothing but air behind the single layer of sheet metal outer bulkhead.

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I have been racing my car for 15 seasons with the original engine mount with zero issues. before I owned the car it was raced in IMSA for 5 seasons with a 3L RSR spec engine.
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also have been using URO HD engine mount (top) for past 5 seasons without issue
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I used this one, worked fine

Great data point

Has anybody used the chassis mount from Mittelmotor:

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Any Thoughts?

I used the Maddog OEM mount and sensed there was a double wall in there when I was welding it in. I turned up the heat because I wanted the mount to stay there.

Quite a bit of square inches of plug welds

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My factory 6 , number 41 with reinforcement done by Eric at PMB Performance just so you guys can see what that looks like

Best Bob B
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Factory mount Complete and factory914-6 sheet metal for $2200
By TWash in classified ,,,,is what I would do on your special 914-4..

Yeah - that’s crazy town price unless you’re restoring an original /6 and HAVE to have original Porsche tin.

Ben’s tin is very affordable. If you must have something more original - Reatoration Design does reproduction stamping of /6 tin closet to $900 when I last checked.

The RD tin is really nice if you want the original stamped look. I like Ben’s tin for my builds since I’m modifying it anyway for the 3.2 engines. It fits well and is reasonably priced. When his products go away, doing a conversion will get a little more pricey.

A conversion parts list will go up in price once I am done by at least 50%