jotto

Asking on behalf of a friend whose motor is eating motor mounts each time he gets on it.
Stock mounts just don't work and so poly or solid seems to be the solution. Some have also suggested chaining the block.

Am I missing something here but wouldn't there be another issue as to why it keeps breaking mounts or is it just because of the torque?
TIA.

Bloodzone

I switched to solids a few months ago after breaking 3 (all on same side) parts store rubber mounts. I'm very pleased. Whole car seems tighter. Less engine movement. Only extra vibration is at my feet in the floor pan. Its nothing major but you can feel it. I also installed a energy suspension trans mount at the same time I went to the solid motor mounts.

BlowAMouse

Solid mounts here.

Broke too many stock / poly in my 69 Camaro to go back...

bence13_33

I'm also running solid motor mounts. I like the way the solid mounts tie the front end together. I remember hearing something about consistency and faster motor response (no slop in the motor mounts when engine torques the car) in drag racing conditions as well. You will see some increase in vibration.

centuryoldracer

I have actually ruined a couple of BB Chevys using solid mounts. Energy suspension is what I have been using with no problems. I like my street cars as smooth as possible.

leadfoot4

Just my humble opinion....the rubber mounts you buy today, aren't made of the same, high quality rubber, that they were made from, back when C-3s were new.

Metalhead140

Ruined how, if you don't mind me asking? I'm putting together a stroker sbc for my vette at the moment and trying to decide between poly and solid, I have both in the garage...

Bloodzone

I totally agree. My SBC shouldn't be braking quality mounts. Thats exactly why I went with the solids. The energy suspension may have been just as good or better but I was sick of replacing broken mounts.

centuryoldracer

Had a fairly sticky tire and making 680 ish horsepower split the # 1 cylinder wall vertically started getting water in the oil. Thought it was a fluke. Put another engine together and it did the same dang thing! Switched to rubber mounts and a limiter never happened again.

flyeri

I like the Energy Suspension too! That's what the previous owner had and when I did the engine swap I put in a new set. ZZ454, 500 lbs torque and no issues.

Aggitated Monkey

I have a 383 stroker that dynoed at 497.4 hp with 468 tq. I'm running poly mounts on engine and Trans. No movement of engine at hard acceleration and no problems with mounts at 1000 miles.

76C3forme

Poly for me..

And I also agree just like leadfoor4 says that the rubber mounts you get today are nothing like the quality of the rubber mounts from "years gone by". Sad, but true..

MIKE80

I used poly mounts on my engine, trans, and everywhere else on my vette, no rubber. Mine has a 385 stroker engine, T56 trans, and 3.70 rear.

mikem350

If you go solid, OK, but use poly or rubber at the trans end. Risk of trans case breakage.

mrvette

Decades ago back when I was drag racing Pontiacs, the trick was a solid welded link chain to the top of the shock mount on driver side, and up/over through a hose to the intake manifold bolt, leave it loose at idle, but snug/tight when torqued over....

and back when knights were bold and liquor was quicker, they had decent AMERICAN made mounts....today, any guesses???

ignatz

"Ruined" how? I am intellectually interested in whether a spreader bar is an essential element for an aluminum block and solid mounts?

From the top in my picture

spreader bar
motor mount
crank shaft

Any opinions or better, actual experience?

cv67

Did you try bolting them to a cyl head instead?
Poly engine, rubber trans. Has to be some give somewhere, or supposed to.
The rubber mounts Ive bought (trans, napas "good" ones") are a joke. The rubber is lousy and threads,somewhere between std and metric guess they all fit kinda. Cant really torque them down.

derekderek

he made it sound as if torque and vibration broke the block at #1 cyl.

ignatz

Mounts are closer to #3 cylinder

terrys6t8roadster

Our C3s [IMO] get very good traction under acceleration. I can watch the air intake bonnet while driving the blue car and there is if any almost no movement. Energy suspension in both of mine.