Technical 265 chevy rear mount/th350 or powerglide front mount ? help..

I'm running a chevy 265/powerglide in a Model A frame and am looking for ideas in making a engine/transmission mount right at the split between the 2. I've searched HAMB and was surprised I could find some ideas.


they make ones recommended for 55/56/57 chevy when swapping to th350.




and one for race cars (that are similar to one idea i'm considering)

SO... has anypne used the front tabs cast into the bellhousing of powerglide or th350 as a mount? I assume they are used in production, I've never seen used.



also considering welding to the adaptor ring i'm using to mount my starter.




any thoughts? will this aluminum ear/tab break off?

 

No can dooooooooooooooooooo!

 

i wouldnt mount it from the ears....i would use the 55-7 mounts or make ones like them.....the howe mounts really wont work because they will interefere with the case.....as far as welding to the plate....i would just make a new plate with the material added - you could even buy a commercially available mid plate and just have to transfer the starter location...

 

The casting tabs are not designed for that purpose and will break under weight and load under torque. The other mounts spread the weight and load under torque over a larger area. This is an old B&M mounting diagram as an example as to how mounts are to be installed.

 

so you are running front engine mounts and the rear tranny mount and you want to add a mid mount also. i think it is a good idea and you probably could get away with using those tabs. i think i would use the bell housing bolts or the idea of welding to the adapter first tho. i would not try to do it without the tail mount.

 

Yes, make a simple left and right mount OFF the bell bolt pattern, you only have to catch 2 bolts than use a donut type mount to frame. I would still run a rear trans cross member and mount as you need something to tie your X or K member together...............................

 

....or scrounge an iron PG

 

I kind if thought most wouldn't think those aluminum tabs would be a good idea. thanks for replys.

your correct, i'm using a hurst style front engine mount and a standard rear transmission mount. I have been told its a good idea to add a mid-mount.
i'd kind of thought using the adaptor ring or piggy backing off acouple of the tranny mounting bolts would be best, just liked the idea of using the aluminum tabs and they are in perfect location in my application.

 

If you can attach the mount to them, so it is not putting any twisting load on the tabs, it would probably last just fine. They were used originally for alignment when machining the case.

 

what do you think about just using the aluminum tabs only for very little weight support, but more to control the rotation of the engine under acceleration/deceleration?
I guess this would be and up/down force on the tab... not twisting?

 

You asked, I would not use those tabs for anything, not ever.

 

The problem is that you need to support weight near the bellhousing.

You probably ought to just make something that is kind of a cross between the two mount kits you have pictured in your first post.

 

Sheetmetal mid plate. Or, suppose nothing at all. How many cars ran around with the front mount and rear trans crossmember, nothing else, and what failures were incurred? I'd have to be in the line that says "zero failures" myself. How much stress is made to happen at the block by mounting it in the front vs side motor mounts? If you were building a drag racer that was going to launch at 6500 RPM and shift at 8500, maybe you'd have some twisting and severe shock loads to consider. Mid mounts can make for a really strong point on a race car. Hell Top Fuel cars and F/Cs hold the front of the engine to the chassis with aircraft hose clamps over saddles bolted to the front plate. Flathead Fords hang off the water pumps up front and then bolt to the torque tube area at the back of the trans. In fact so do those heavy ass V-12 Zephyr/Continentals. No issues or worries there either. Did I miss something?

 

I don't know of failures, I been researching and seems it's recommended by many. I considered not using any, but was thinking it couldn't hurt and I have some very tight clearances and less moving around the better.

 

"what do you think about just using the aluminum tabs only for very little weight support, but more to control the rotation of the engine under acceleration/deceleration?"
I guess this would be and up/down force on the tab... not twisting?"
Rotation is twisting............................
The only situation I can see to run a PG would be in racing or a numbers matching car . Must be something special your building to be running a PG, let's see some pic's of the hole build.

 

I ran my truck like that for a few years (big block/th400 swap), it worked, trans mounts went bad pretty much immediately. The trans case is not designed to take the load, fortunately they make them kind of overkill. Although the 4x4 guys had trouble with them, probably because of the transfer case hanging off the back. Chevy made special transmission cases with heavy cast aluminum dust covers to hold them together.

It'll be interesting to see what you come up with.

 

In 58 the corvettes had a 3 point mount. used a mount at the very front of the engineand extreme rear of the transmission. My buick nailhead does the same. many flathead fords where mounted this way. and the dodge floating power also.

 

no, it's nothing special...... just building for myself like I want, (within my budget).

my signature is a link to build tread

 

the more I think about it, this "hurst" style front mount and the wider than original rear mount should hold this low horsepower engine pretty well....

thoughts?

 

It will hold it, just thought you were worried about "mid" weight on the Aluminum bell? The wide stance on the rear support doesn't really have anything to do with stability (over stock), it's still sitting on a 3"-4" rubber pad.........................................

 

That looks pretty stout from here. Frame's boxed, there's enough padding involved to absorb vibration (it looks like there is), I see you want to gusset the center crossmember too. The remaining space may be futher limited getting mid mounts involved. On my Packard 8s there's a flat metal plate that goes to a vulcanized bracket on the frame. In the parts book it's called a stabilizer and it goes on the back of the block at the trans mounting area. It's not real stout but mounted in shear it's pretty effective. I'll try to get a picture today of it in place, maybe it will inspire something simple and effective without undue stresses to your bell housing.

 

The only nagging concern I have, is that the transmission was not designed to support the weight of the engine. It's not a huge increase in load, though.

The front mount you have will keep the engine from twisting, which is a big concern on the 55-57 chevys when swapping from the bellhousing mount, to rear trans mount.

 

Is this one of those 500 hp, 9000 rpm 256s? I appreciate (dont always understand) the engineering experience, expertise and advice of you guys, but this is a 265/pg combo. I also realize this question and info is applicable to guys running stouter combos.

 

If your using the front and standard trans like you said the "racer" ones will definatly be your easiest. We use them on our 1/2 mile dirt Super Stock with the standard side engine mount and NO trans mount without any problems. Actually the standard way of mounting a Chevrolet 6 inthe early 50's had one steady mount only on the right side. If there is to much stuff on the left side you don't need to use that side.
We did the same mounting you are using on a 53 210 hard top and never had a problem with it either using no center mount. Good luck.

 

If it was mine I would NOT build it with a Hurst front mount and PG trans mount at trans tail shaft only.
To much weight in middle not supported, no matter how much HP, or it's intended driving. JMO
I am in the same frame of mind on my own project, front Hurst mounted Baby Hemi & GM 5 speed with tail shaft rear mount. Since mine is a manual trans over auto I can run a steel scatter shield were I will find a "friendly" area to weld a bracket from bell to frame with a donut front rubber style mount. You might want to entertain the same idea and have Aluminum ear's welded to your PG bell housing.........................................

 

Here's a shot of the Packard stabilizer:


This is right at the back of the engine. Notice the frame mount is a vulcanized part. Pairs of fasteners stop rotation, the plate is 1/8th steel. Maybe it inspires something simple for yours, and perhaps other's too.

 

with the large holes in the tabs on the tranny i was thinking that a set of the original 55-57 chevy front motor mounts/struts might work good and provide some support without putting strain on the tabs.

 

like the steady rests on a 55 T bird?

 

yeah, well, those are a bit large for what he's trying to do. Have you ever worked on a 55 Bird? Kind of hard to find pics of the steady rests in situ...