davek9

Speaking SOLID mounts only, the Anchor mounts (available at Rock auto and others for a 70's Ford Bronco) are approx 10mm lower (thank you Hans!) than the Volvo mounts Roger sells.
I use the Anchor mounts when doing a Twin Screw Supercharged engine as they allow the SC Drive snout to clear the stock fender cross brace w/o modification, else I'll install the Volvo Mounts from Roger as the oil pan will sit level with the lower engine cross brace as it does with the Stock Liquid mounts.

That's my 928 cents on MM's

Dave K

checkmate1996

i have Volvo mounts no issues what so ever after four years...

siscogts

7 years with Volvo mounts. No problems or vibration to report. They settled for the first kms, and they are still there where they settled. Rennlist is ful of information and pictures:engine height is about the same as any other 928 with new mounts.
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I changed mounts to other 928s,some originals and some where Volvo or Mapco, or Febj bilstein, no. Change in vibrations, comfort, driveability.

I am very satisfied,

dr bob

My first motor mount replacement included new Porsche mounts. Ten-plus years later, I needed to solve a seepage issue with a new oil sump gasket, and decided to put new mounts in while I was in there. I sourced some of the Volvo-style mounts from one of our vendors, and did a few mods to the brackets to get them to work. There' some posts with pics from that effort someplace here. Anyway, the mounts I took out were still perfectly serviceable. Had I known I would have left the Porsche mounts in place. I put the Volvo-style mounts in though, and placed the Porsche mounts back into the "good used spares" bin.

The first set original in the car lasted about 15 years before they needed replacement, FWIW. The car is fitted with the original undertray and has the motor mount cooling ducts plus the heat shields in place to protect the mounts. Wandering back through the before-and-after pictures I took the first time I replaced them, the difference in height now between new Porsche then and new Volvo-style now is minor if anything. Maybe a few millimeters I think, comparing the pictures. Not enough to disqualify one over the other just on the dimensions. I'll be watching the Volvo-style mounts to see how they last. I can't point to any difference in NVH, mostly because I put new gearbox mounts in at the same time I did the MM/OPG replacement. The gearbox mounts made a very significant difference in noise and smoothness coming up into the back of the seat.

I tried a few of the gearbox mount hacks, including stuffing the gap with different rubber pieces, and finally putting new urethane in there to fill the spaces. No hack was anywhere close to the quiet that the new Porsche gearbox mounts delivered.

khalloudy

My factory mounts are about 15 years old at this point.. replaced them back in 05 or 06. I do feel vibration at idle, specially when I am in D at a light or something. What is the expected life from the factory mounts?

P.S. i did notice that the manifold in not flush with the cross brace anymore but sits a cm or so lower.

Adamant1971

7/8ths on the ones I just I stalled. Will try to measure my 87 with 6 years 45k tomorrow.

chart928s4

I guess you guys who install them often would know, but my Volvo mounts (Corteco? I think) only sat a little higher (~3/8") when new and are now settled. The height is indistinguishable from new Porsche mounts and they're smooth as butter.. @85euro928 - Thom, one quick data point: I never installed a turbo, but I assume it means the intake will be off. One negative with these mounts is that the higher initial height made aligning and reconnecting the hard lines a minor PITA, especially the rear fuel lines.

85euro928

Thanks.

jcorenman

Thom, I promised you some measurements for the 12+ year-old Anchor solid-rubber mounts in our GT. I guessed that the bottom of the pan was 1/4" below the bottom of the lower cross-member. That engine now has a pan spacer so the actual measurement was 0.685", but without the spacer would be 0.310" (8mm). Which is consistent with Dave K reported. These are solid-rubber Anchor mounts that predate our ownership, they look and act fine so we've left them. The belly-pan has the cooling ducts but the heat-shields have been replaced by headers.

With the spacer, we've about 5mm between top of the cross-member and the pan and a few mm between pan and aluminum belly-pan.