Just wanted to throw this out there and get some feedback. My truck is a 47 1/2 ton AD. I'm going to use a 265 V8 (lot of family history with this setup) in this truck and was going to use a 5 speed manual trans. I have been also considering using an automatic trans (200R4). Since the 265 uses 2 front engine mounts (no side mounts) the transmission will need to be supported off of the back of the engine. What I'm thinking might work is using something similar to this: https://www.danchuk.com/ItemForm.aspx?It...b5-ceabc840a895 I know that these mount are for a 55 - 57 car, but am using them as an example only. The rear motor mount crossmember would need to have a section cut out for the transmission to fit and the remaining crossmember pieces attached to the left side of the frame and right side of the frame would need to be configured for these trans mounts to work. The tail shaft of the transmission will also be supported. I'm staying with a solid front axle that will be dropped 2 inches so no frame mods will happen there and I was just thinking of any flexing of the frame that might cause any damage to the drive train. It won't be a work truck but will be my daily driver. Dan
I agree with your approach for supporting the engine/trans. What are you planning to do to mount a late model starter to the early block? Ray
This is an example of what's available for the starter mount when converting to an auto trans. https://www.danchuk.com/ItemForm.as...Category=49479621-6589-48ec-87b5-ceabc840a895 Dan
Looks like a hokey way to put the wrong parts together...but I guess it might work. I think that if I had a good reason to use a 265, that I'd also have a good reason to use an old fashioned transmission behind it. I guess I don't think like most guys, though
The Hurst style front motor mount would work to keep the engine from rocking. You must have a very good reason to try and stay with the 265. Maybe rethink the project a little and life will get easier and cheaper.
Is it the 265 inch displacement that is key to the use of an early engine, or do you have a specific engine that has been in the family forever that you want to use for this project? If it is the displacement, there are both 262 and 267 versions of the SBC that would retain that aspect and allow the benefits of a later block (and possibly heads) and bolt directly to the 2004R as is. If it is a specific engine you have, well, then I guess your plan to retain it will get the job done. In any case, best wishes with your project. Ray
You are still going to have to do lot of fabricating to be able to use that mount on the 47 frame. You will end up building mounts on the frame similar to what a stock 55 Chevy sedan has off it's frame for the trans mount. There isn't anything to bolt it to there now. Since you will end up cutting out the crossmember that is under the bellhousing you will have to box and reinforce the frame or the weight of the cab will eventually push down on the outrigger cab supports on the frame and twist the frame rails until the cab sits right on the top of the frame. The reason that a lot of AD trucks look bent at the cowl when the hood doesn't fit any more because the front of the cab has sagged. It's up to you if you are just bent on having an automatic with that engine but to me it's a lot of extra expense and trouble when you can use a V8 truck cast iron bellhousing that matches the engine and bolt the bellhousing to the frame with stock V8 truck mounts and be done with it. Basically bolt the engine in place by bolting the bellhousing to the crossmember, level the engine and set up your front mounts using the Hurst style mount and figure out what to do with the steering interference with the exhaus. A stock 265 manifold might help there but I never tried it. You will still most likely have to move the steering out some.
There is a long family history with this engine. I just had the engine completely rebuilt and bought the 47 Chevy truck a couple of years ago for this project. I bought the truck which had no engine/trans and it will be a frame up build. Lots of options are available that would make some things so much easier but I have my preferences on what I would like to do. I could have went with a crate 350, auto trans and MII suspension but that is not what I wanted out of this truck. I could bore you to death with my whys of doing this but I won't. I still may go back to the idea of using a T5 5 speed which would be super easy to install. I'm jst trying to explore the option of the automatic trans.
I figured that there was something special about your using that engine and that's that and done. A couple of reasons for choosing an automatic and the main one is that there is a possibility that for you the main driver, it isn't practical to have a standard shift trans. For you the install of the automatic would just mean a few hundred dollars added expense and a few hours added work to reinforce the frame and fab brackets to work with the mounts. If you are good with that so be it. Just make sure that you put in the added support in the frame if you remove that crossmember so the cab doesn't sag. I've already junked one frame on my truck because of that issue.
I'm thinking the weight of the engine/trans hanging off those Danchuk mounts inside the frame would go a long way in offsetting the cab mount twist.....the loads are opposed, not in the same direction. However, I agree in principle that some provision should be made to maintain structural integrity of the frame rails. I would think a sort of "U" shaped cross member could be installed, similar to the stock one, to tie both sides together. Other configurations come to mine...it's doable with a little thought and effort. Ray
It might help some Ray but on mine the rails had twisted until the cab was laying flat on the frame rails and keeping the emergency/park brake rod from moving. That was with the truck having a Camaro subframe welded on it and a lot of plating on the subframe install. It's one of those if you fix it before you have a problem you won't have a problem things that I discovered too late on that frame and have seen dozens of time since then on other trucks.
I am considering the automatic just because it's convenient(ok, it's also the lazy way to shift). The manual shifting is no problem should I go that way. I will be using a local shop to do the install with the motor mounts and transmission mounts/boxing of frame/support. I've lurked around this site for quite a while and just recently joined and really appreciate the responses and advice so far. Dan
I did some searchin' just to see what there was for frame reinforcement and I found this: http://www.progressiveautomotive.com/installations-kits-parts/tubular-x-members.html A bit of overkill, but would work I think. They do make the tubular crossmember for the 47 - 54 Chevy trucks,. I figured just boxing in the frame would help but may still not be enough support. Would this type of crossmember require the frame to be boxed? Dan
The style crossmember shown in the link is almost useless, in my opinion. It is a common design in aftermarket frames and is usually called an "X" member but is anything but. An X member, as is found in most full ch***is convertibles and many closed body types, truly forms an X and the height and/or reinforcement of the center cross point is key to it's torsional rigidity. The tubular structure pictured in the link offers precious little connection between right and left frame rails and absolutely no useful torsional resistance that I can see. What Mr48chev and I agree on is that if you sever or remove the existing crossmember that currently supports the bell housing, the outrigger forward cab mounts will be applying an unrestricted downward twisting force to the frame rails and the cab can/will sag in the cowl area. I don't know how much interference there may with existing crossmeber when you fit the 2004R trans to the engine, but the idea is, it would be a good thing to keep it's structural integrity although it may need modification for clearance. Even a true X member may not provide sufficient resistance to twist of the frame rail as is provided by the general style of he stock cross member. Ray
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