New motor mounts/Stock perchs

[KyFarm]

I bought some new motor mounts for my HT383, I am going to use the stock perches for the motor crossmember.

The hole in the perches is larger than the head of the bolt holding the mount to the crossmember.

Is a washer the only thing that is supposed to be holding the engine in? Seems kinda lightweight to me.

Is there any reason not to fab a thicker washer and put between the bolt head and the crossmember?

[Captainfab]

There is supposed to be a heavy washer between the bolt head and the mounting bracket. IIRC it is about 1/4" thick and ~ 1-1/4" in diameter.

[KyFarm]

thank-you, I'll make those myself..

[burnin oil]

If you are going to beat on it you may want to convert to a clamshell mount. I have a couple mounts like this in my truck that have hammered the threads and work loose. Also beware that the auto replacement stores mounts may have the wrong bolt thread. I have 2 sitting here that had 1/2" holes instead of 5/8. Another thing is to double check that they are the newer style. There are still some factory style out there that can tear apart. There is nothing wrong with this style mount but there are better options.

[Captainfab]

Yes there are better designed engine mounts such as the '73+ clamshell style but the urethhane '63-'72 mounts are much tougher than the replacement rubber mounts.

[burnin oil]

Yes they are. I bought a set but are not the correct ones. The manufacturer said they fit but it isnt like anything I have seen on a factory chevy. Got quoted around 50 bucks apiece for urethane in the correct mount. Remember i said that i am running these currently. I have broken both styles but the clamshells do stay put. I just wanted to make sure that the OP was aware of his choices and a current pitfall. When someone mentions a 383 I automatically assume roughly twice the power of a stock engine. Say 300hp and up.

[KyFarm]

using Prothane 7-509, came with correct bolts, hopefully they will work.

I'm not sure how to link a picture from another site

[68Gold/white]

Some of the frame brackets came with bigger holes, like yours and some came with smaller bolt holes. I don't knoe when the switch was made. Larger holes may have been made for easier installation at factory, and yes large heavy washers were needed under the bracket.

I call the older type mounts, "sandwich" mounts. They are essentially two pieces of metal with rubber bonded to each piece. Enough power (and/or age, combined with any fluid leaking on them...) will pull apart the drivers side mount. LOL, tyou wil know it when the fan starts rubbing on the fan shroud. THese mounts serve the purpose, BUT the clamshell mounts are much better. I've seen some here adapt the 73-up clamshell mounts (using the 73-up frame brackets, also). A much better mount and no worries about the mount pulling apart

The 68-72 pickups had big blocks in them, BUT the 72 went to a clamhsell type mount on the big block ONLY. My 68 has a 396 engine, and I am going to convert to the 72 type clam shell mount setup. My 67 will get same type mount also, even though its a small block, because the mounts are that much better....