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RichPugh
QUOTE(mb911 @ Sep 28 2020, 08:56 PM) *

http://www.914world.com/bbs2/index.php?sho...39906&st=40

Please see the last page. A bit of info


Thanks, man. I shot Bob an email. That thread showing the position differences between the Naro and PMS mount is quite enlightening. I wish I would have simply gotten the PMS mount... I was trying to support the Naro guys.
RichPugh
QUOTE(gandalf_025 @ Sep 28 2020, 06:05 PM) *

This is what they did to the 914-6 race cars
back in the day to clear a tab on the early aluminum
911 cases..

Click to view attachment



This "notch", placed close to the shift rod knuckle, would def clear the case. It wouldnt help with the other issue being the forward position of the engine and trans, but would def clear the case.
Tdskip
Great discussion.

Sounds like the Naro mount needs some additional thickness to either where it welds to the firewall or where it attaches to the engine.

Won't being 1/2 inch too far forward put a lot of stress on the transmission ears?
RichPugh
QUOTE(Tdskip @ Sep 29 2020, 12:10 AM) *

Great discussion.

Sounds like the Naro mount needs some additional thickness to either where it welds to the firewall or where it attaches to the engine.

Won't being 1/2 inch too far forward put a lot of stress on the transmission ears?


Thats another concern I have with where the lump is placed. It's definitely not sitting in the trans mounts squarely. I dont think the solution is adding "thickness" to the welded portions of the Naro mount... MAYBE modifying the mount position for the bar at the end of the welded mount "ears" could be a fix for them moving forward. In my case, I think the cradle section that mounts to the engine can/needs to be modified (basically reengineered) to correct it, lifting the engine upwards every bit of 3/4" and rearward about 1/2". The mounts on the firewall are positioned in a way that it currently allow room for the rear brake bias assembly to simply be moved upwards and still fit (tightly) under the engine tin shelf. If we were to reposition them further upwards, that would have to be completely relocated. The welded ears can stay... the cradle that mounts to the engine should be addressed, in my case... probably, LOL.
mb911
QUOTE(RichPugh @ Sep 29 2020, 08:10 AM) *

QUOTE(Tdskip @ Sep 29 2020, 12:10 AM) *

Great discussion.

Sounds like the Naro mount needs some additional thickness to either where it welds to the firewall or where it attaches to the engine.

Won't being 1/2 inch too far forward put a lot of stress on the transmission ears?


Thats another concern I have with where the lump is placed. It's definitely not sitting in the trans mounts squarely. I dont think the solution is adding "thickness" to the welded portions of the Naro mount... MAYBE modifying the mount position for the bar at the end of the welded mount "ears" could be a fix for them moving forward. In my case, I think the cradle section that mounts to the engine can/needs to be modified (basically reengineered) to correct it, lifting the engine upwards every bit of 3/4" and rearward about 1/2". The mounts on the firewall are positioned in a way that it currently allow room for the rear brake bias assembly to simply be moved upwards and still fit (tightly) under the engine tin shelf. If we were to reposition them further upwards, that would have to be completely relocated. The welded ears can stay... the cradle that mounts to the engine should be addressed, in my case... probably, LOL.



That is a great point and easily modded.
RichPugh
Here's just a couple pics showing exactly where the mount ears were welded into place as well as thee Naro instructions. they are exactly where Naro tells you to put them. They're exactly 4" from the bottom ridge of the firewall to the center of the cross bar. please excuse my rudimentary bottom level line made up of a file and a socket, lol.


Click to view attachment

Click to view attachment

Click to view attachment



RichPugh
QUOTE
In my case, I think the cradle section that mounts to the engine can/needs to be modified (basically reengineered) to correct it, lifting the engine upwards every bit of 3/4" and rearward about 1/2". The mounts on the firewall are positioned in a way that it currently allow room for the rear brake bias assembly to simply be moved upwards and still fit (tightly) under the engine tin shelf. If we were to reposition them further upwards, that would have to be completely relocated. The welded ears can stay... the cradle that mounts to the engine should be addressed, in my case... probably, LOL.


QUOTE
That is a great point and easily modded.


I was considering adding a new 2nd "bar" to the existing mount. One that would lift the engine up 7/8" and position it back 1/2". Something like this (excuse the remedial sketch). The blue just signifies welds all the way down the bar.

The other option would be to cut off the face mounting plate that connects to the engine case, cut a new one that lifts the engine up 7/8", wre-weld it into place and then space it off the case w/ 1/2" spacers/nuts/washers... something. Ughhh


Click to view attachment
Tdskip
Why couldn’t we “just” do this?

Add thickness to the mount and relocate the u-shaped piece that boots to the engine up and back? Excuse pre-second cup of coffee drawing but you get the idea.

Click to view attachment
Tdskip
One other way to go it is to add spacers on the mount (provided they are very strong), like the green shown here on the u-shaped piece.

Click to view attachment

This is how Lotus did it on the Elan which, granted, only has a 1.6L engine.
Click to view attachment
RichPugh
QUOTE(Tdskip @ Sep 30 2020, 08:21 AM) *

One other way to go it is to add spacers on the mount (provided they are very strong), like the green shown here on the u-shaped piece.

Click to view attachment


This is what I mentioned above too... just using spacers for the fore/aft adjustment and figuring our another way to "lift" the engine up. Maybe Bob @ Naro will help. We have (at least) 2 identical situations... 'Live Free & Drive' is having identical issues. Maybe Naro made a bad batch?
Tdskip
QUOTE(RichPugh @ Sep 30 2020, 10:54 AM) *

QUOTE(Tdskip @ Sep 30 2020, 08:21 AM) *

One other way to go it is to add spacers on the mount (provided they are very strong), like the green shown here on the u-shaped piece.

Click to view attachment


This is what I mentioned above too... just using spacers for the fore/aft adjustment and figuring our another way to "lift" the engine up. Maybe Bob @ Naro will help. We have (at least) 2 identical situations... 'Live Free & Drive' is having identical issues. Maybe Naro made a bad batch?


So, in theory, if you welded the existing mount 3/4 higher than instructions and then added 1/2 spacer we should be OK?
mb911
QUOTE(Tdskip @ Sep 30 2020, 08:24 AM) *

QUOTE(RichPugh @ Sep 30 2020, 10:54 AM) *

QUOTE(Tdskip @ Sep 30 2020, 08:21 AM) *

One other way to go it is to add spacers on the mount (provided they are very strong), like the green shown here on the u-shaped piece.

Click to view attachment


This is what I mentioned above too... just using spacers for the fore/aft adjustment and figuring our another way to "lift" the engine up. Maybe Bob @ Naro will help. We have (at least) 2 identical situations... 'Live Free & Drive' is having identical issues. Maybe Naro made a bad batch?


So, in theory, if you welded the existing mount 3/4 higher than instructions and then added 1/2 spacer we should be OK?


Yes that is what I figured as well.
Mark Henry
QUOTE(Mark Henry @ Sep 25 2020, 12:09 PM) *

I mounted the bulkhead mount to the motor, then I raised the engine and trans into position and bolted up the rear trans mounts. I got the engine raised up to where I wanted it to sit and I tack welded the mount in place. I put in enough tack welds to hold the weight of the engine, took out the jack and confirmed that it was sitting correct with full weight.

In lining up my home made bulkhead mount I found several areas I had to mod and/or clearance before I tacked it in. I got it right first time but I could have easily cut out the tack welds and reposition it if needed.

Only when I was totally happy and tacked in did I remove the engine/trans and fully weld in the mount.



-Bolt the mount and the transmission to the engine.
-Put it in the car and bolt up the rear transmission (to body) mount bolts.
-Use your jack to get the correct height of the front.
-install the seal, hook it on under the engine tin edge, get it perfect before you weld.
-Weld the tacks in an easy to grind out area in case you make a mistake.
-Tack it well enough to hold the weight and check.
-Check your seal, not too tight... not too loose, it should hook on the engine tin perfectly.
-Remove engine/transmission and finish welding.

Doing it this way my seal hooks perfectly onto the tin. Except for finding center I used no measuring tools for the job, I let the trans mounts do that job. I'd say my engine placement is as perfect as you can get.
My shift rod is straight but it only clears by 1/4" and I have a Tangirine shifter console mod.
RichPugh
QUOTE
So, in theory, if you welded the existing mount 3/4 higher than instructions and then added 1/2 spacer we should be OK?


Welding the ears in 3/4" higher would/could result in interference complication with the rear brake bias unit (that can currently just move upward slightly and remain connected as is). I was going to leave my 'ears' in place on the firewall and re-engineer the cradle portion of the mount... the U-shaped plate that mounts to the engine case, if it was cut off and either re-welded in a 3/4" higher position, or re-cut and drilled higher and welded in new... Not sure. It's a lot to deal with. I didnt want to pull the engine back out so... I guess I'm going to have to at this point.
RichPugh
QUOTE
Bolt the mount and the transmission to the engine.
-Put it in the car and bolt up the rear transmission (to body) mount bolts.
-Use your jack to get the correct height of the front.
-install the seal, hook it on under the engine tin edge, get it perfect before you weld.
-Weld the tacks in an easy to grind out area in case you make a mistake.
-Tack it well enough to hold the weight and check.
-Check your seal, not too tight... not too loose, it should hook on the engine tin perfectly.
-Remove engine/transmission and finish welding.

Doing it this way my seal hooks perfectly onto the tin. Except for finding center I used no measuring tools for the job, I let the trans mounts do that job. I'd say my engine placement is as perfect as you can get.
My shift rod is straight but it only clears by 1/4" and I have a Tangirine shifter console mod.


Did you have to relocate the rear brake bias unit? How high off the firewall bottom ledge is the centerline of the bolt holes in your ears? How long ago did you do this? This was my initial thought process too but like a good boy, I followed the instructions confused24.gif

Lesson learned... but my ears are already welded. I know for a fact I could not have had them welded any higher without removing and relocating the rear brake bias unit.
JOEPROPER
Maybe you could weld to the front of the U shaped bracket, a piece and drill holes to mount to the front of the engine. This would put the engine / trans assembly back a little further in addition to raising the engine in the engine bay... 2 pieces of channel may work for that with a little work to make it look okay...
Mark Henry
QUOTE(RichPugh @ Sep 30 2020, 01:13 PM) *

QUOTE
Bolt the mount and the transmission to the engine.
-Put it in the car and bolt up the rear transmission (to body) mount bolts.
-Use your jack to get the correct height of the front.
-install the seal, hook it on under the engine tin edge, get it perfect before you weld.
-Weld the tacks in an easy to grind out area in case you make a mistake.
-Tack it well enough to hold the weight and check.
-Check your seal, not too tight... not too loose, it should hook on the engine tin perfectly.
-Remove engine/transmission and finish welding.

Doing it this way my seal hooks perfectly onto the tin. Except for finding center I used no measuring tools for the job, I let the trans mounts do that job. I'd say my engine placement is as perfect as you can get.
My shift rod is straight but it only clears by 1/4" and I have a Tangirine shifter console mod.


Did you have to relocate the rear brake bias unit? How high off the firewall bottom ledge is the centerline of the bolt holes in your ears? How long ago did you do this? This was my initial thought process too but like a good boy, I followed the instructions confused24.gif

Lesson learned... but my ears are already welded. I know for a fact I could not have had them welded any higher without removing and relocating the rear brake bias unit.


I actually cut out, modified and welded in a couple of gussets in the brake bias area. I had to clearance a few out other areas, one to clear the shiftrod boot.
But note mine was an RJ mount copy that was copied by someone unknown to me, I scavanged in parts from a 911 mount and the plans had a few mistakes as well.
sawzall-smiley.gif smash.gif welder.gif
ClayPerrine
Unfortunately, all of our parts are not produced by highly trained Porsche factory engineers with lots of experience and lots of testing.

Bob's mounts, like the Rich Johnson mount are made by talented enthusiasts with lots of time and limited money. They don't really get the same level of testing factory parts do. So you are likely to have issues like this one. Plus, after almost 50 years, these cars have been customized so much that no two cars are alike.

So we build this stuff, and hope everyone understands that it will require tweaking for your use case.


I have been friends with Rich Johnson since the middle 90s. He makes great parts, and I have one of his conversion mounts in the 4.0L car. When I converted it from a 2.4 to the 4.0 engine, I had to buy a different mount because the half that fits on the 2.4 won't fit on to a 3.6 engine case. We built a jig on a 901 trans, and made the transmission mounts for the Cayman trans fit the jig.

We put the engine and trans in the car, and the trans mounts were almost 2 inches to the rear. I thought the jig was wrong, but when I pulled the engine/trans back out, I found the 3.6 engine mount was about 2 inches thicker than the 2.4 engine mount. This was done to clear the pulleys on the 3.6. It made the engine tin too short on the front too. Because I have a clewett serpentine belt setup on this engine, I shortened the plate in the front mount to the same height as the 2.4 mount. Then everything fit correctly.

That is an example of "You may have to tweak it to get it to fit your application right."

sawzall-smiley.gif smash.gif welder.gif
Steve
QUOTE(Mark Henry @ Sep 30 2020, 10:29 AM) *

QUOTE(RichPugh @ Sep 30 2020, 01:13 PM) *

QUOTE
Bolt the mount and the transmission to the engine.
-Put it in the car and bolt up the rear transmission (to body) mount bolts.
-Use your jack to get the correct height of the front.
-install the seal, hook it on under the engine tin edge, get it perfect before you weld.
-Weld the tacks in an easy to grind out area in case you make a mistake.
-Tack it well enough to hold the weight and check.
-Check your seal, not too tight... not too loose, it should hook on the engine tin perfectly.
-Remove engine/transmission and finish welding.

Doing it this way my seal hooks perfectly onto the tin. Except for finding center I used no measuring tools for the job, I let the trans mounts do that job. I'd say my engine placement is as perfect as you can get.
My shift rod is straight but it only clears by 1/4" and I have a Tangirine shifter console mod.


Did you have to relocate the rear brake bias unit? How high off the firewall bottom ledge is the centerline of the bolt holes in your ears? How long ago did you do this? This was my initial thought process too but like a good boy, I followed the instructions confused24.gif

Lesson learned... but my ears are already welded. I know for a fact I could not have had them welded any higher without removing and relocating the rear brake bias unit.


I actually cut out, modified and welded in a couple of gussets in the brake bias area. I had to clearance a few out other areas, one to clear the shiftrod boot.
But note mine was an RJ mount copy that was copied by someone unknown to me, I scavanged in parts from a 911 mount and the plans had a few mistakes as well.
sawzall-smiley.gif smash.gif welder.gif

AFAIK vellios (rip) designed the mount first and then Rich Johnson copied it. I have the Rich Johnson mount. Couldn’t be happier with it. Tilting the engine with the Other mount makes no sense if you have heat exchangers, etc in the way.
I also have no shift rod or engine height issues. My shift rod is a straight rod with no bends. Worked fine with the previous 2.7 and now 3.2 power plant.
Mark Henry
QUOTE(Steve @ Sep 30 2020, 01:53 PM) *


AFAIK vellios (rip) designed the mount first and then Rich Johnson copied it. I have the Rich Johnson mount. Couldn’t be happier with it.

For all I know my mount could have been copied from a Vellios. confused24.gif

To do a /6 you either need deep pockets or you have to be handy. biggrin.gif
These days maybe a bit of both. shades.gif
RichPugh
QUOTE(JOEPROPER @ Sep 30 2020, 01:22 PM) *

Maybe you could weld to the front of the U shaped bracket, a piece and drill holes to mount to the front of the engine. This would put the engine / trans assembly back a little further in addition to raising the engine in the engine bay... 2 pieces of channel may work for that with a little work to make it look okay...



This is actually a good idea. Instead of cutting the original u-shaped mounting plate off, just cut a new plate, weld it to the existing plate, drill new holes in it and thru the old plate for the correct height position and space it off the engine a bit more to make the fore/aft adjustment needed to push it rearward.

This seems much less daunting than re-engineering the bar or the whole cradle portion or re-welding the ears up higher creating more problems.
Tdskip
Like this - with the red being thicker steel to help located it back toward the rear of the car?

Click to view attachment
mb911
QUOTE(Tdskip @ Oct 1 2020, 10:31 AM) *

Like this - with the red being thicker steel to help located it back toward the rear of the car?

Click to view attachment



Personally I would just make the mounting flange thicker.
porschetub
QUOTE(RichPugh @ Sep 26 2020, 01:32 PM) *

QUOTE
Not mounting the bar to the engine and then mounting the engine with transmission and bolting up the rear mounts is the OP's big mistake.
This step must be done every time...I don't give a flying fuchs who made the mount.



Lesson learned. Listening to the manufacturers installation rules/guidelines/instructions was my mistake. It simply DOES NOT position the engine in a good place (for my goals, at least)... so... I can do what you suggested, re-welding the mounts to the firewall in a higher, more ideal position but it doesnt fix the situation with the engine being about 1/2" too far forward closer to the firewall. The firewall kinda pitches backwards slightly so it might move it back marginally.

I will either:

1. Drop the engine, re-engineer the crossbar/cradle portion of the Naro mount to position the engine UP 3/4" and further rearward about 1/2"... Decent work but massive improvement.
2. Re-weld the firewall mounts up 3/4" UP and deal with the forward positioning... not ideal but better.
3. Leave it just as it is and just mod a shift rod bar to work... probably what I'll do in the interim.


Sorry to see you have this situation,not uncommon to see an engine too low,mine was by 15mm so because it was a copy of an original "6" setup I was able to modify the mount on the case by moving the centre bolt tube that runs the bolt to the rubber mount.
The fact that your engine is also too far fwd is strange and tells me there is some issue with the design...seems odd the member/vendor hasn't chimed in poke.gif confused24.gif .
I would expect your trans bolts will be somewhat out of square with the fwd position you have now ??.
Options you provided ;
1. yes and IMO the best but not easiest solution as you will have to re:engineer the centre bar by cutting it and using flat bar steel to create required offset up and fwd,you will need to jig it up to get this right.
2. I can't see how you would manage to cut/relieve the welds on the b/head and then you still have the issue of alignment for and aft.
3. you could but you may find its more of a bandage and may later on make you wish you had taken option #1.
From what I have seen you don't want the engine tin a tight fit on the sealing rudders otherwise installation of the engine can be rather hard ,after I moved my engine up I found removing the side tin was the only way the engine go up fully otherwise you start bending the tin,but it is still in a better position height wise or atleast in my case.
Maybe a mod on the case mount could be the only solution but don't really know,good luck sorting beer.gif .
sixnotfour
here is the numbers to help
http://www.914world.com/bbs2/index.php?sho...=346616&hl=
Tdskip
QUOTE(sixnotfour @ Oct 2 2020, 10:09 PM) *


Very helpful, thank you.

I woke up dreaming about this last night, sad but true, so I should probably figure out an approach and just be done with it.

I am leaning towards mounting the Naro Mount as instructed on the firewall, thereby not having to deal with the rear brake stuff, but extending the engine mount up by adding in additional steel plate.

The thickness of the additional steel plate will move the engine back away from the firewall and I should be able to readily raise the bolt holes by the 3/4 of an inch necessary.

@md911 I think that’s what you suggested, and it seems like a viable option I’ll be at with some heartburn from having to fabricate and shape the new mounting surface.

One open question that I don’t believe it’s been addressed – it looks to me like the Naro Mount may transmit more in VH then one that uses regular engine mounts. Yes/no/maybe?
mb911
For those not yet having installed one I would suggest this unit.. No I don't get a kickback or have anything to do with the company but this is the simplest and allows the most clearance of any mount on the market. Click to view attachment
RichPugh
QUOTE
Very helpful, thank you.

I woke up dreaming about this last night, sad but true, so I should probably figure out an approach and just be done with it.

I am leaning towards mounting the Naro Mount as instructed on the firewall, thereby not having to deal with the rear brake stuff, but extending the engine mount up by adding in additional steel plate.

The thickness of the additional steel plate will move the engine back away from the firewall and I should be able to readily raise the bolt holes by the 3/4 of an inch necessary.

@md911 I think that’s what you suggested, and it seems like a viable option I’ll be at with some heartburn from having to fabricate and shape the new mounting surface.

One open question that I don’t believe it’s been addressed – it looks to me like the Naro Mount may transmit more in VH then one that uses regular engine mounts. Yes/no/maybe?


First off... Definitely more vibration. It's essentially a solid mount just with a urethane bushing.

I think i'm gonna do the same thing... Weld a new "U" shaped plate to the existing one and re-drill the mounts about 3/4" - 7/8" higher and the thickness of the new face should push it back almost enough to put the trans mounts square in their seats. It might need another 1/4" spacing off the case... will find out. Pulling the engine back out tomorrow headbang.gif
Tdskip
QUOTE(RichPugh @ Oct 3 2020, 04:33 PM) *

QUOTE
Very helpful, thank you.

I woke up dreaming about this last night, sad but true, so I should probably figure out an approach and just be done with it.

I am leaning towards mounting the Naro Mount as instructed on the firewall, thereby not having to deal with the rear brake stuff, but extending the engine mount up by adding in additional steel plate.

The thickness of the additional steel plate will move the engine back away from the firewall and I should be able to readily raise the bolt holes by the 3/4 of an inch necessary.

@md911 I think that’s what you suggested, and it seems like a viable option I’ll be at with some heartburn from having to fabricate and shape the new mounting surface.

One open question that I don’t believe it’s been addressed – it looks to me like the Naro Mount may transmit more in VH then one that uses regular engine mounts. Yes/no/maybe?


First off... Definitely more vibration. It's essentially a solid mount just with a urethane bushing.

I think i'm gonna do the same thing... Weld a new "U" shaped plate to the existing one and re-drill the mounts about 3/4" - 7/8" higher and the thickness of the new face should push it back almost enough to put the trans mounts square in their seats. It might need another 1/4" spacing off the case... will find out. Pulling the engine back out tomorrow headbang.gif


Frustrating to be sure.

Not sure I want to deal with the NVH...

live free & drive
The Naro mount has Delrin bushings - the Patrick mount has urethane bushings with a steel center sleeve -which I believe to be a better set up for anything but a full-on race car (NVH-wise).
Tdskip
Interesting - I just welding the Naro mount in 3/4 inch higher than directions but did NOT have to adjust the transmission mounts at all. It located the rear mount perfectly - like totally bang on perfect. I am running a 3.2 but don’t think that makes any real difference.

Maybe the slant of the firewall is enough to better locate it once it is mounted higher?
RichPugh
QUOTE(Tdskip @ Oct 24 2020, 05:09 PM) *
Maybe the slant of the firewall is enough to better locate it once it is mounted higher?


I assumed that same result if I had welded it higher. Did you have trouble with room for the rear brake bias valve?
Tdskip
QUOTE(RichPugh @ Oct 24 2020, 04:27 PM) *

QUOTE(Tdskip @ Oct 24 2020, 05:09 PM) *
Maybe the slant of the firewall is enough to better locate it once it is mounted higher?


I assumed that same result if I had welded it higher. Did you have trouble with room for the rear brake bias valve?


I removed it but don’t think I actually had to. I did screw up in that I left the line to it under the mount rather than on top but that is fixable.

I was under the gun to get the drivetrain in so I could move the car so I punted on that for today.
JOEPROPER
@RichPugh How did you make out with that engine mount?
RichPugh
QUOTE(JOEPROPER @ Nov 6 2020, 11:55 AM) *

@RichPugh How did you make out with that engine mount?


I was able to ignore it while procrastinating and doing nothing. Well, doing other stuff, completely unrelated to the 914, as per the 914 project handbook, "Step 4: Stop working on 914 and do other stuff".

LOL

I'm planning to finish the stuff in the front this week or next... I.e., putting the fresh air blower box and fan back in, wiring and plumbing the fuel pump, dropping the tank back in... THEN I can roll it off the lift, spin the lift around, put it BACK up in the air with the lift positioned where I can remove the engine... and THEN I'll stare at the mount until I repeat step 4 again.

The goal is to weld a new plate to the face of the engine side of the mount with the holes positioned up 3/4"-1" upwards... that should do it.

-Rich
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