A guy where I work has a '68 Chevelle that puts out 500 RWHP (yes, it's been Dyno'd) and he told me that he broke several transmissions before he finally figured out that the cause was the solid motor mounts. He now runs standard rubber mounts, not even polyurethane. He said "the motor's gotta move". So I'm thinking 'no' on the solid mounts...
my buddy and I came up with the bright idea of having a stock mount welded up as a solid on a 70 torino with a hot little 302 and leave the rest of the mounts stock and it shook the car like a out of balance blender on frappe.. we took it out and ran a stock mount and never had a problem if your worried about breaking the mount then use a torque strap (length of chain a eyelet on the frame and a bolt on the block (never the head use the block )
vibration good :evilsmile My car shakes and shimmies so much, I did not notice a difference when I put the PROTHANE on
Man, your support is different from mine. My supports do not have a "center rivet". The surface of the support in the foreground of your picture must be flat in order for the support holes to line up with the mount holes (ie,. no stand-off of support to mount). I see where yours appears to be ground flat, but that plate (where your ground bolt head is) is only an 1/8" thick on my supports. Sounds like we have two different types of supports with different plate thicknesss.
That center rivet is a safety mechanism. The mounts I got from Checker for $9.00 each did not have it, so I took them back and spent $19 each for the ones with the rivet. My original mounts have it as well. I decided not to go with urethane...
I was going to make my solid "support/mount" like the attached pic (drill a hole through the plates, bevel the edges of the pin and hole, fillet weld and grind flat on bottom side), but my pal, Ed (fan2488) said no - that he could do better (and he did, pics to come). Just an idea.
That looks good Rick...do you think there will be a problem with the rubber melting during welding? Okibono, bring a mount over and we can try it.
I welded 2" strips of metal on each side of the stock mount. Its been working great for about 50 runs and street driving so far.
The only reason you'd be concerned with the rubber melting is that it would make for a sloppy weld, I assume, because the rubber is "rendered useless" when the two plates are welded together anyway. I dunno about the problem of the rubber interfering with the weld - maybe you and Oki can tell us. Ed welded plates on the sides of mine (similar to what Killercomet did, I'm sure). But there was a twist - he ground enough of the rubber and a "center plate" to "inset" the 1/8" thick plate. (Man - I gotta get those pictures - I'm not splaining too good :16suspect )
