455 Olds in place of 454 in 76 GMC (frame to engine mounts?)

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MikeB

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I found P/Ns 464715 and 464716 on GmPartsWiki.com when searching for "bracket, engine mt diesel" for 1978 light truck. I then did a Google search on the P/Ns. This page came up as well as some others.

http://www.2040-parts.com/nos-78-79...engine-mount-supports-464715-464716-i1979990/

Hope these info helps you.

I spent hours on the GmPartsWiki site several years ago looking for P/Ns for steering column parts and motor mount brackets and clam shells when I went from a 250-six and 3-on-the-tree to a 350 V8 and TH350. Takes a lot of patience!
 
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AuroraGirl

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Forget the 455, I have a few 260 I can sell you, little does anyone know, they are the peak of small block performance and very desireable!!!
 

OldBlueDually

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Mike B, thank you! I actually did call the guy to find out his seller name to see if those still existed, they do not! At least now I have the info and I can run and find what I need. Thank you very much for this!

AuroraGirl, thanks for the 260 offer, but I am and Old's guy through & through....we will be sticking with an Old's 455 in this baby. No replacement for displacement, right! :)
 

HotRodPC

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If you have ever seen a 455 on a engine dyno, you will see they don’t have a torque curve. They have a torque plane! They start out with excellent torque, hit their torque peak, and levels off with excellent torque.
And at low rpm. Not a good idea to spin an Olds 455 over about 5800 rpm unless you lighten the rotating assembly, girdle the mains and maybe even splayed main caps. I so regret getting rid of my Olds 425 Forged Crank. It would have gone into any Olds 455 and made a 425 Cu In Olds and with some work, be able to spin that that bitch to 6500 on the shorter stroke, forged crank. Dreams Come and Dreams Go. I've had the opportunities for lots of good dreams and they all went to **** and NEVER happened.
 

HotRodPC

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Mike B, thank you! I actually did call the guy to find out his seller name to see if those still existed, they do not! At least now I have the info and I can run and find what I need. Thank you very much for this!

AuroraGirl, thanks for the 260 offer, but I am and Old's guy through & through....we will be sticking with an Old's 455 in this baby. No replacement for displacement, right! :)
For sure, stick to the Fo Fitty Fi !!! I'll be watching that one. Be sure to have a thread about that truck in the under construction section.
 

AuroraGirl

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Mike B, thank you! I actually did call the guy to find out his seller name to see if those still existed, they do not! At least now I have the info and I can run and find what I need. Thank you very much for this!

AuroraGirl, thanks for the 260 offer, but I am and Old's guy through & through....we will be sticking with an Old's 455 in this baby. No replacement for displacement, right! :)
There's a reason my family called our cutlasses with 260s gutless, because they wrecked the other cars at the stop light!
 

JBswth

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Hi gents, I have a 76 GMC crew cab dually that "had" a 454 in it that was previously removed before I purchased it. My 1969 455 Olds Rocket will be going into this truck.

My question is, is there anything off the shelf I can buy for frame to engine mount? I have the motor mounts themselves already bolted on the engine. Curious to know if something works!

I will be using the stock TH400 trans that is in the truck, so the adapter plate & all the goodies are on the way to make it work. If I could purchase these frame to engine mounts that would be nice, I am just not sure if I can, and if I can.....what do I use?

If anything, will make some, but I would rather not.

Thanks!!
A pre 72 engine will run and hide from a later, smog-controlled lower compression milder cam engine, but you might have to use dished pistons, as the 69 Olds engine had over 10 - 1 compression, and they don't sell 100 octain anymore. It might ping bad in today's pump gas.
 

Matt69olds

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There were 515 built in '68. All were 455's with TH-400's. I believe all were W-30 cars. This one has the red fender wells and Ram-air (intakes under the bumper). This is the under hood of another H/O. I can't recall if my friend's car had A/C, but I believe it did.

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Many years ago The Olds Club of America published the vin and selling dealer of each of the 515 68 hurst Olds. Imagine my surprise when Weise Olds here in Kokomo (my hometown) Indiana sold the first one. I figured a special car like that would have gone to top brass at the Oldsmobile headquarters.

Another myth that won’t die, the 455 was installed right there on the assembly line, in spite of the corporate ban on engines bigger than the 400 in the intermediate cars. The rumor was Olds shipped the cars to Demmer Engineering for the Hurst Olds conversion, where the 455 was installed. Nope, they drove the cars to Demmer for the speciality parts to get installed.

Also, there was no special order to how the cars were built. The first car delivered to Demmer wasn’t necessarily the first one built.

The 68 Hurst Olds is my dream car as well. Along with a 70 GS Stage One, 69 GTO, 70 Chevelle, 70 Challenger, 65 Polara, tge list goes on.

If anyone is bored and needs some entertainment:

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I have seen the car featured in this video, the guy brought it to the Olds Homecoming in Lansing Michigan. It was still covered in the barn dust and debris. Supposedly the guy stopped driving it after it got rear ended in the late 70s/ early 80s.


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Matt69olds

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I don’t recall how deep your going into the engine, or if it’s been installed yet, but if the engine has some miles on it you might consider replacing the timing chain.

I’ll never understand why the OEM thought it was a good idea to cover the cam gear with nylon, but lots of engines came that way. Eventually the nylon cracks and flakes off, falls into the oil pan, and clogs up the oil pump pickup. Next thing you know, the engine has low oil pressure.

Timing chains are much easier to replace on a engine stand!!!
 

Dave M

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Many years ago The Olds Club of America published the vin and selling dealer of each of the 515 68 hurst Olds. Imagine my surprise when Weise Olds here in Kokomo (my hometown) Indiana sold the first one. I figured a special car like that would have gone to top brass at the Oldsmobile headquarters.

Another myth that won’t die, the 455 was installed right there on the assembly line, in spite of the corporate ban on engines bigger than the 400 in the intermediate cars. The rumor was Olds shipped the cars to Demmer Engineering for the Hurst Olds conversion, where the 455 was installed. Nope, they drove the cars to Demmer for the speciality parts to get installed.

Also, there was no special order to how the cars were built. The first car delivered to Demmer wasn’t necessarily the first one built.

The 68 Hurst Olds is my dream car as well. Along with a 70 GS Stage One, 69 GTO, 70 Chevelle, 70 Challenger, 65 Polara, tge list goes on.

If anyone is bored and needs some entertainment:

xc_hide_links_from_guests_guests_error_hide_media

I have seen the car featured in this video, the guy brought it to the Olds Homecoming in Lansing Michigan. It was still covered in the barn dust and debris. Supposedly the guy stopped driving it after it got rear ended in the late 70s/ early 80s.


xc_hide_links_from_guests_guests_error_hide_media

Hey Matt, not boring at all. I love it. I have a '67 GS 400 Buick hardtop over here. For 1967 that old girl still turns tricks.
 

Magna86

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You need the mounts from a 403 trans am. They use clamshells like a Chevy.

Here are the brackets you need for the engine side.

Then use the Chevy clamshells on the frame. You may have to move them on the frame to different set of mounting holes though.

Finding diesel mounts are impossible
 

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