455 Olds not lining up well in 76 GMC crew....

[OldBlueDually]

Hey there gent's, I need some advice on this here issue.

I finally got to the point of dropping in the engine to see what needs to be done to get it mounted up. I bought some frame to engine mounts from summit racing that looked like they "should" work, this was just a shot in the dark.

As you can see from the pics, they don't work. As for the engine mounts themselves, I just re-used the ones I had on it.

Are any of you aware of a combination that will work to get this baby mounted correctly? I have been searching for a set of Olds 350 diesel mounts (from GM trucks '78 to like 82 I believe) and did find some from a guy, but he is in the process of moving and has not come across them.

So I just need a nudge here on what to do as this is the first time dealing with putting an Olds in a GM truck.

As you can see, to mount up the transmission is way off too. I have my adapter plate in place and ready, but don't want to be forcing things to fit.

Thanks in advance!!

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[Blue Ox]

Move the mount on the crossmember back, or get a BOP trans?

 

[Turbo4whl]

Is the transmission on the cross member in the rear? Looks like there is enough room to move the engine back. If the bell housing and the back of the engine needs to be where it is in the picture, move the front engine cross member forward. Is there room underneath for the engine cross member to move it forward?

I understand, if you move the trans/transfer case back, the drive shafts are the wrong length.

 

[bucket]

Are the engine and trans in line with each other and the engine is simply higher? If so, it looks like the trans just needs raised at the front and the engine lowered at the rear.


Keeping in mind that I'm not at all familiar with Olds mounts, here's what I would do. Buy new rubber mounts that are for the same application as your frame stands, so that the widths match up. Then drop it back in place for a test fit. Measure how far forward the frame braces would need to go so the frame stands will sit on them properly. Lift the engine out and relocate the frame braces the needed amount. Then drop the engine back in and mark where to drill mounting holes in the frame braces, for the frame stands to bolt to.

 

[Memaloose]

What about moving the cross member back? It's hard to figure it out because you can't see and measure everyhing.

 

[Dave M]

@OldBlueDually

Would like nothing better than to be able to call around with some beers and help you sort out these issues. Unfortunatley in this situation, it's hard to come up with answers, from just pictures. i'm sure you will get there.

 

[OldBlueDually]

@Blue Ox unfortunately even a BPO trans would not help this situation as the trans would still be sitting in the same spot. I though the same too as I do have a long shaft Olds 400 that needs to be rebuilt.

@Turbo4whl Yes I can move the engine back further, and the trans is bolted to the crossmember with new hardware. No, there is not enough room to move the engine crossmember forward either.

@bucket Right now it looks like to line up engine & trans is around 6 inches yet, so quite a bit off, the pictures are hard to see its that far off though. I do like your idea of the engine mounts for that truck though, and I may buy a set and see what that will do for me.

@Memaloose are you talking of the engine crossmembers on the frame, or the transmission crossmember? I really cannot move either of them either direction without that messing up something else unfortunately.

@Dave M I hear you there! I will have to try a few things suggested here in this thread and see what happens. Won't know until we try!!

 

[OldBlueDually]

@bucket what I meant was 6 inches down to line up trans...I should have mentioned that.

 

[OldBlueDually]

Ok so posting by smart phone/dumb user sucks....I had a double post, so had to edit this one with some BS

 

[Blue Ox]

If I'm understanding your problem correctly the motor mounts are too far forward. Is there a height problem too?

Forgive my ignorance, but isn't the front crossmember where the suspension attaches? I have a K so I'm not as intimately familiar with a C.

If that's the case I see two choices. Either mill up a piece of steel to span and adapt to the forward location, or move the trans crossmember back and shorten the driveshaft.

I would just shorten the driveshaft. It's a crew cab, there's plenty of driveshaft, and it's the cheapest and easiest option.

 

[bucket]

Seeing what different rubber mounts are available is probably the best place to start. Maybe one of the designs will have the engine sitting lower than it does now. Again that's just a guess because I'm not familiar with them at all.

 

[bucket]

These frame stands look like they are a lower profile?

https://www.summitracing.com/parts/opg-c240246/make/oldsmobile

And new rubber mounts that may or may not be the correct width.

https://www.summitracing.com/parts/trd-9592/make/oldsmobile

 

[Dave M]

Here's an old thread that mentions the 5.7 L diesel mounts.

https://www.gmsquarebody.com/threads/455-olds-swap.8946/

 

[cstew47]

Wow, what a great idea putting a 455 in a Chevy. I've always been an Olds guy and have owned several 455's and 400's. I wish I could give you specific advice, but, It looks like you are getting plenty already. In my simplistic brain, it looks like a matter of adjusting the trans crossmember and fabbing up some motor mounts. You have the adaptor plate, so, it seems to be just a matter of customizing the fit. Good luck with the project and hopefully you will post a follow-up when you finish it.

 

[JeffK10America]

Well I e seen a 472 Cadillac engine trans combo put in a C10 so I know it’s possible!
Not my show, but I would suggest matting trans to engine . Then set into place and build brackets accordingly.
You can do anything you set your mind to do! I put a 455 in a Buick Regal . Custom motor mounts. Have fun with that . Will be a killer set up!