ajr2820

I am swapping the 350 with a 455. I am using the mounts for the 350 since I already had the brackets. I understand this will work, however, does this cause any height differences with this set up vs. swapping over to BB mounts and brackets? The reason I ask is that I am running a Torker intake and want to be able to gain as much hood clearance as possible.

TripDeuces

Engine mount attachment points are at the same height and place on both engine blocks but the 455 is approximately 1.5 inches larger in height and width.

don71

You will have plenty of hood clearance with a Torker in 72 cutlass.

You are correct in using the sb mounts and brackets on your 455. The engine will be exactly where it should be and everything will be right. The only major thing that is changing is the deck height of the engine.

oldcutlass

I'll ad that the crank centerline is in the same mounted position in both engines. This is a good read.
https://classicoldsmobile.com/forums...tion-list.html

joe_padavano

Wow!
My work here is done.

ajr2820

Good to know. Thanks. Given that it will keep the crank centerline in the same location, I wonder why they had 2 mounting systems to begin with?

joe_padavano

In most years there WEREN'T two different mounts. This was ONLY in model years 1969-1972 and ONLY in the Cutlass line, yet it has spawned about a bazillion threads.

GM went though a massive and costly recall for broken motor mounts across most car lines in the late 1960s. Because of this, Olds (and other divisions) phased in new motor mounts with an interlocking design. Olds originally used this design only on the high torque BBO motors, but by 1973 it had spread to all mounts. FYI, the new early style mounts (Anchor 2261) now incorporate the interlocking feature as well, so the need for two different designs has been overcome by events.

I'll also take this opportunity to again suggest that we stop calling them "350" and "455" mounts. Through the 1968 model year, the first design mounts (with the 2261 rubber mounts) were used with EVERY Olds block in an A-body, from 330s through the 455 in the 1968 H/O. The second design mounts (the stronger ones with the 2328 rubber mounts) were similarly used with EVERY Olds block from 1973-up, including the 260, 307, and 455. It was only model years 1969-1972 where the two designs were used in the same year.

oldcutlass

In case you didn't notice my post was a previous recording of one of yours.

joe_padavano

I did and I'm OK with that. Imitation is the sincerest form of flattery.

ajr2820

Makes sense now. Wasn't aware of the issues with the old mounts breaking.

joe_padavano

The original 1960s vintage mounts were simply metal end plates with rubber molded in between. The driver side is in tension, so when the rubber ages, engine torque causes it to separate. Couple this with the solid rod style throttle linkage used in the 1960s, and that's a recipe for disaster. This is also why Olds went to a cable throttle linkage in 1968. The cable is much less likely to jam the throttle open if the motor mount separates.