engine mount brackets - frame side question

[panelrodder81]

My truck, 73 2wd, has obviously been hacked on over the years. Last fall I lost cylinder 1's main bearing and pulled the motor for a crate motor. It wasn't till I was putting the new motor back in that I noticed that the two frame side brackets, the angled brackets that motor mounts bolt to, where different than one another. I didn't snag a pic but I have found some supporting images.

It appears that there are some that sit the engine high in the engine bay and basically go straight from the top the rail to the xmember like this:


and then some sit the motor lower in the engine bay with a bend in the bracket like this:


As evidence to my truck's hacked on past.... drum roll please... I have one of each. The driver-side is the bent kind and the passenger is the straight kind. So my nice new crate engine sits leaning to the driver-side in the engine bay.

Normally I wouldn't care that much but the trans mount stripped out on the passenger-side because of it and the exhaust on the truck is **** but I couldn't put my nice exhaust on because the header flange hits on the driver-side because of the bent engine mount bracket. If I could get another straight bracket for the driver-side then I could bolt on my nice exhaust.

I hypothesized that that it was straight brackets for SBC and bend brackets for the BBC but I seem to see WAY more bent brackets than straight and it seems that BBC's were a little more rare than SBC's sooo my hypothesis is kinda out the window.

SO, the question I have is that even with the photographic evidence posted I can't find any information on what years or engines each kind of bracket was from to try and find a replacement.

Help?

-Panelrodder

[bdiamond]

There are a few different length engine side clamshells. My truck has the "dropped" looking frame mounts. It is a SB truck.It had about a 3" clamshell. There is a 2.25"ish one also. I used a pair of the 2.25" to lower the engine in mine. I have a few spares of each PM me if you could use one.

[79Betty]

I'd try and use the dropped ones if possible. Lower the center of gravity...
Posted via Mobile Device

[panelrodder81]

Originally Posted by bdiamond

There are a few different length engine side clamshells. My truck has the "dropped" looking frame mounts. It is a SB truck.It had about a 3" clamshell. There is a 2.25"ish one also. I used a pair of the 2.25" to lower the engine in mine. I have a few spares of each PM me if you could use one.

By clam shell are you taking about the engine side mount, the part that bolts to the motor first? What I'm questioning is the bracket under the motor mount in these pictures. The part bolted to the frame. However if I swapped the clamshell on the motor for one that lifted it enough for my exhaust to clear I could be happy w that too.
Posted via Mobile Device

[panelrodder81]

Originally Posted by 79Betty

I'd try and use the dropped ones if possible. Lower the center of gravity...
Posted via Mobile Device

I can see the point but the height difference isn't enough for me to worry to much about especially in the face of have to replace the entire exhaust when I have a really nice setup just standing in the garage that could go in. Also Tue truck is dropped pretty healthy amount so even the motor lifted would probably be lower than stock on the bent brackets. If I can make up for it w clamshells as was suggested above though then I'd totally agree. Ultimately I'm after clearance for the exhaust.
Posted via Mobile Device

[panelrodder81]

Btw the clearance issue is at the collector flange on block hugger headers for the sbc, if that helps.

Panelrodder
Posted via Mobile Device

[bdiamond]

I got the shorter ones off an 88 or so 350 out of a 4wd truck if that helps

[KrazyRay]

The lower frame side engine towers are for SBC and the non lower ones are for BBC. The reason is the BBC needs to sit higher for exhaust clearance to the frame. You could use either one for SBC, but I would go with the original lower towers to make sure everything aligns properly.

[panelrodder81]

Originally Posted by KrazyRay

The lower frame side engine towers are for SBC and the non lower ones are for BBC. The reason is the BBC needs to sit higher for exhaust clearance to the frame. You could use either one for SBC, but I would go with the original lower towers to make sure everything aligns properly.

Here is a question that just occured to me, if I put a lower tower on the passenger-side where there currently is a tall tower, would the leveling out of the engine free up clearance on the driver-side by rotating it down to level?

-Panelrodder

[cory d]

i think there is about 4 different engine mount towers. half ton and 3/4-1 tons arent interchangable

[panelrodder81]

I've worked out a deal for a set of the low towers that I'll pickup tomorrow. Based on my thought two posts and basic geometry I think just lowering the passenger side will clear the way for the headers.

I will try and post information on this further when I get the project done.

-Panelrodder