Hello,

I've been on here reading for sometime now after searching for Oldsmobile info. My project involves a 1965 Chevrolet C-10 that came with a 1975 4-bolt 350 chevy and sm420 muncie when I first got it. I finally managed to wheel and deal my way into the engine I wanted, a 455 Oldsmobile. It's a 70-72 block with "C" heads and came out of a boat. I still have to tear into it and see what I have ahead of me (just got it saturday), but I figured I would introduce myself now before I have any questions.

I plan on using 5.7L Olds Diesel mounts that were used in the 73-87 C-10s to mount this in my truck. I have a Th400 for now, but I plan on finding a ST-10 or Muncie to go behind it eventually.

Thank you in advance to anyone willing to help me along my way.

- Cameron

 

Sounds like a great project. For sure one good thing is the 455 boat engine had stick shift cranks. You do have to use the pilot brg adapter from one of the venders. Also did you get the stick shift flywheel with it.
Just hope the engine has not sat around very long with water in the cyl's.
When you bought the engine was there problems with it. As to why did they remove it from the boat.
Was the engine complete , top to bottom, front to rear ?

Gene

 

Yeah, I noticed the stick shift crank. Big bonus for me. Thanks for the tip on the adapter though! The engine is complete top to bottom, front to back. The story goes that the boats hull was toast and the previous owner (a metal fabricator) made a trailer out of the boat trailer, cut the engine out of the hull (still has wood attached to motor mounts from where it was cut) and filled the cylinders with oil and stuffed in a corner for a year until he could find another boat.

The oil in the engine is clean and it turns at the crank with a prybar easily. I traded my 1975 350 sbc for it straight across. The 350 had smogger 993 heads, some fancy chrome dress up, headers, performer intake/carb and was complete. He wanted to build a 383, so it worked out for both of us.

Here's some pics (apologies for the watermark, I had already resized them for the blog I write for):

 

Just be careful - some of those boat motors were reverse-drive, as in they ran backwards!!
Could be a problem with transmissions!

 

Most definitely. I'm going to tear it down and do a full rebuild on it. I'd rather have the peace of mind.

 

I have never seen a Olds w/reverse run. All I have dealt with have been jet drive.

What heads are on it ?
You might want to put all the boat parts up for sale.
You can scour the wrecking yards for the pulleys and get the water pump length, and power steering pump and brkts. You may have to have p/s hoses made up. Also get the Alt brkts, non A/C car is on the passenger side. A/C cars Alt. is on drivers side,above P/S pump. get the pulleys as a match set, with the water pump they came off of.
Just get a B.O.P. bell housing and you can use the trans set up already in the truck.

Gene

 

Thanks for the reply Gene. It's got C heads on it. The info on the brackets is very helpful thank you. I was entertaining the idea of running a BOP bellhousing with the SM420, because I'm sure it's strong enough but it's more of a rock crawler transmission, so I figure I'll stuff the th400 up in there if I don't find a good sporty 4 spd before I get it running. Not really what I want to do though, as I'd like a manual in the truck.

AFA the boat parts, I have a buddy that does hi-perf boat work and might want them. Probably going to try and trade them for a vortec MPFI intake (for my DD to get rid of the spider injector system) and some cash.

 

See I know absolutely zero about boats but those water logs that have hoses connected to what would be the thermostat housing in a car application makes me believe this is a water jet boat. Is there any boat guys on here?

 

Those manifolds run water to keep them cool. The round things are called snails and they are used to keep the lake water from running back in.

If you can get the "W","Z" repo style manifolds or you can run headers.
When you get the pulleys and P/S pump, just tell parts guy the car you got them from and make sure you tell them with or W/O A/C. Be sure to measure the length of the pump on the car and the new one is the same.

Use the biggest rad you can and use a clutch fan & shroud or a big electric fan. If you use electric, set it up as key on all the time or opp for the thermostat controlled one.
Run the 2.5 exhaust sys and run all the way to the back, hump over the axle and out to the side. I think they sound better that way as to just dumping in front of the axle. But that is up to you. I really like the Dynomax muffs.

Gene

 

Thanks for all the info Gene! It's very apparent why you're so well respected here. I'll keep all of this in mind. I was hoping to run headers, but we'll see, the headers on the 350 that used to occupy the engine bay came together in the middle like a set of block huggers, but were long tubes. I'll have to look around and see if I can find something that clears like they do.

Hopefully a trip down to the local salvage yard will net me the accessories I need. As long as it's not off a 307, I can use any olds setup I find right?

 

I have seen a few of these conversions. They only one I had my hands on was a 72. We use 68/72 Cutlass big block Olds headers. At that time i think they were Hedman herders. You need ones for Oldsmobile, chubby's will not fit.

You need the accessory's from any 350/403/455, 68 to 76. That will be the easiest to use. Other years are possible, but may need work to fit the big block.

Gene

 

Looks Nice!!!!

 

This helps a lot. The 72 frame is identical to my 65, and they're both not far removed from the 73-87. Thanks for getting me started on where to look for headers. You've been more help than you could know. Thanks!

Cameron

 

Thanks Jason!

 

What is the latest update with pic's??

Gene

 

Below are some shots of the truck. I have everything for it, but it was badly abused so I'm working on the interior as well as the exterior. So some things are taken off in pics. It was originally a 1965 Fleetside long bed. In the pics you can see the 1962 GMC Stepside long bed that I swapped beds with. I have 15" aluminum blade wheels for it, but since it's just rolling at the moment, I've just got the junk wheels on it for now. My dad does roofing so the seat is out of a 72 C-60 and the interior chrome (horn button, door handles, window cranks etc) is out of a 1962 C60. Wish I had taken the gauge cluster too, even though it wouldn't fit in my trucks dash. As far as progress since my post, I haven't even got the marine parts off the 455. Hope to get started on that tomorrow. Talked to my friend though and he seems interested in taking them off my hands. We'll see.






(that's me between the two trucks above)




The 62 is up for sale right now by a friend. If anyone wants info, just PM me. It's got a 60* GMC 305 V6 and 3 spd Muncie.

BTW the dusty old 350 chevy is the motor I traded my 455 for.

 

I had never seen a reverse run engine until a friend of mine show me a 351 Windsor Ford engine in his speed boat. He was looking for a starter and I had one. Except it was meant for a normal Windsor engine.

 

I'm not up on boats, but what kind of boat was it, and what was the drive ?

gene

 

Updates?

 

Coming into this thread late, but I want to clarify something in an earlier post. The SM420/SM465 truck transmissions do not bolt to the traditional ('581) BOP bellhousing. The bearing retainer on the truck transmissions is larger than on the car transmissions and will not fit the hole in the bellhousing. You can have the hole in the housing machined to match, but then the hole for the clutch fork pivot ball gets very close to the hole for the bearing retainer. You really want to weld the original hole, move the pivot ball, and use a truck clutch fork. Alternately, convert to a hydraulic throwout bearing.

The other solution is to find one of the extremely rare BOP bellhousings for the truck trans. These were only made for a couple of years for the 3/4 ton and 1 ton trucks with the Olds diesel and SM465 manual trans. I let one get away on ebay a few years ago because I didn't know what it was at the time (and neither did the seller, apparently).

 

Right now I'm as far as having got all of the boat parts off of it. Cleaned up the valve covers as well and found they've led a pretty harsh life and have been welded in a couple spots, but I'll probably run them as I have no plans for the truck being much of a show piece. As far as tearing into the engine, it's been a slow process. Between my 6 year old step son, my 9 month old daughter, working 40+ hours, and a million other things.. one of which being a wild goose chase after a P0306 code on my daily driver truck (a 96 c2500 5.0L), which so far points to what I believe to be warped or cracked upper intake manifold or a problem with my valves. Idles at 2k in park or neutral and 1k with a misfire-like vibration under load, runs fine in gear and wastes a ton of gas. Probably in the lower single digits at the moment. Good ignition system, tps, iac, and new gaskets for the upper manifold and throttle body. It has 255,000 miles.

Anyways I'm getting off track on that nonsense. I'm hoping I'll be able to get the heads off if I get some free time tomorrow or sunday. I'm also trying to get ready for SEMA, as I have media passes for my website, so that's consuming quite a bit of my time. I really want to see what I've got going on under the between the heads and oil pan at this point, it's my big goal when all of these other things are no longer looming over me.

Thank you Joe for your insight on the Olds bell housing, I appreciate any info I can garner from you. I can imagine those sm465 Olds bell housings are as rare as rare gets.

As far as my build, I don't think the truck will ever have the sm420 mated to the 455 at any point in time. I plan on running a ST-10 or a Muncie behind it, when I can find one that suits my budget.

 

Started a build thread here:

https://classicoldsmobile.com/forums...ed-c-10-a.html