Anyone install solid motor mounts on there BBC C3?
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
I've said this before on many occasions and have done it myself. You can run a solid mount on the drivers side and a rubber (or other material) on the pass side. This works pretty good for a hot street car-unless you like doing reverse burnouts 
ltlevil
ltlevil
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I run Morosso solid mounts on the motor and really like them. No vibrations at idle or anywhere and a nice clean crisp blip of the throttle.
You must run a flexible tranny mount.
I always thought small block and big block mounts are the same. I know when I ran my conversion from small block to big block I just used the stock small block motor mounts and distributor.
You must run a flexible tranny mount.
I always thought small block and big block mounts are the same. I know when I ran my conversion from small block to big block I just used the stock small block motor mounts and distributor.
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
There are different mounts, short and wide, or tall and narrow. The difference seems to be with the frame horns. When I swapped from a small block to a big block, I bought new mounts for a big block. They were the tall and narrow ones. They wouldn't fit the frame. I had to get the short and wide ones which are listed for a small block.
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Thread Starter
Drifting
Joined: Jun 2002
Posts: 1,620
Likes: 7
From: Orlando Florida
I run Morosso solid mounts on the motor and really like them. No vibrations at idle or anywhere and a nice clean crisp blip of the throttle.
You must run a flexible tranny mount.
I always thought small block and big block mounts are the same. I know when I ran my conversion from small block to big block I just used the stock small block motor mounts and distributor.
You must run a flexible tranny mount.
I always thought small block and big block mounts are the same. I know when I ran my conversion from small block to big block I just used the stock small block motor mounts and distributor.
I stopped by the local speed shop today and they had three different types of solids for sbc or bbc.
Thanks for all the replys
Joe
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Sorry Joe but I don't. I have bought 3 sets of mounts over the years for my bigblock and never was given a choice. I just asked for morosso solid mounts for my bigblock and that was it. Same with the previous poly mounts. No choice. I did use the 75 original small block mounts at first.
Sorry I can't help
Sorry I can't help
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Pro
Joined: Jun 2005
Posts: 583
Likes: 61
From: USA
poly trans mount? I'd agree.
the engine is cast iron, the frame is steel, the trans is a cast aluminum case. we all know that under cornering, acceleration, braking, pot-holes, etc, there is some defllection, even if only a few hundreths of an inch, that's why the measure torsional rigidity of truck chassis for advertising points. Between the cast iron, steel, and cast aluminum, I think it's the aluminum that will yield (i.e. crack) first.
therefore the poly trans mount, especially if using steel motor mounts, to provide some controlled acceptable degree of movement.
if you had one of those full-on roll cages extending to the front suspension pick-ups, then maybe you could use a steel trans mount with steel motor mounts, because you've eliminated the deflection, and increased the torsional rigidity of the cradle that's holding the motor trans combo.
my 2 cents.
the engine is cast iron, the frame is steel, the trans is a cast aluminum case. we all know that under cornering, acceleration, braking, pot-holes, etc, there is some defllection, even if only a few hundreths of an inch, that's why the measure torsional rigidity of truck chassis for advertising points. Between the cast iron, steel, and cast aluminum, I think it's the aluminum that will yield (i.e. crack) first.
therefore the poly trans mount, especially if using steel motor mounts, to provide some controlled acceptable degree of movement.
if you had one of those full-on roll cages extending to the front suspension pick-ups, then maybe you could use a steel trans mount with steel motor mounts, because you've eliminated the deflection, and increased the torsional rigidity of the cradle that's holding the motor trans combo.
my 2 cents.
