Inliners International
Posted By: Lucky'z Garage Need help planning my GMC 302 install - 12/11/13 10:26 PM
Hi fellow inliners!!!

So, I bit the bullet, went big and purchased my first inline 6. And by big, I mean I got the holy grail GMC 302. Why you ask, cause it was available locally, I wanted an inline 6 for my build and was familiar with the history of the 302. I did all my research online to ensure I have a true 302. Best of all, it came with a story that sounded true enough. Found in a christmas tree farm COE with 40k original miles on it. This guy bought the COE simply for the motor, drove it home, pulled the engine and scrapped the COE. It's been sitting for 3 years since he pulled the motor.

So he decides to sell it for a decent price(at least I thought so), I drive to his place in Auburn and load it up to take home for my 1941 Chevrolet Master Deluxe build(which I bought when I was about 18 with no motor). After a call to Patrick's antiques, I find out that I have a lot of work to do to make this motor work with my passenger car, but needless to say, I'm not discouraged cause I know I've got a real 302 with the right head(casting #2193983). What i've determined is the block is a first year block(1952) and the head is from 1959. Not sure why, but oh well, I've got a 302.

So, my asks for help are the following:
-What bellhousing should I use for this 302 going into a saginaw 4 speed and able to mount onto the 1941 rear mounts? Anyone on here have one?
-What engine mount do I use? I have one from a 270 but the original in the 1941 is 2 motor mounts on the front, do I need to buy a timing cover motor mount to make this work? I understand the 302 is longer, so will that original 1941 2 point mount work or should I stick with the single truck mount from the 270? Anyone have one?
-What rear end will work under my 1941 master deluxe yet align to the saginaw through an open driveline? Anyone have one?
-What driveline do I use? Anyone have one?
-Flywheel and starter and converting to 12 volt? How do I know what to use here? The guy I bought the engine from said that it was already converted to 12 volt, was he talking about the flywheel and how can I tell?

I'm sure I'll have more questions, but would be great if you could help get me started.

Humbly,

El Lucky Deuce
Welcom to the site... Check the Tech Tips in the column to the left and do a search in the Forums , hope for some ol' fart like Beater \:D to chime in and if that fails look here., http://www.stovebolt.com/techtips/engine_swap2_302.htm
 Originally Posted By: jalopy45 #4899
, ...hope for some ol' fart like Beater \:D to chime in ...

OK, I'll answer to that. I became a grandfather yesterday!

Lucky, Welcome! Concord? I attended my 50th high school reunion this summer. I went to Clayton Valley. I had a '41 Chevy coupe for a while back then. It had a 261. Is yours tan and was it run into a power pole?

A Saginaw will bolt to the GMC bell housing. The stock rear motor mounts will work. You may have to build a tranny mount. The front mount on your 302 will be 1 1/2" in front of the Chevy frame holes. I would notch the frame and weld in a 1/2" plate to extend the cross member and use a stock mount. I used the yoke style mount to put a 270 in my '53 pickup and I would not do that again. You will need to move the radiator ahead 1 1/2 to 2". Usually you can move it to the front side of the radiator support. There may be some cutting involved but not much. Your 6V starter will work fine on 12 V if you don't grind it too long on starts. No problem with a well tuned engine. If your flywheel has 4 bolts finding a 12V starter is not an option. If it has 6 bolts you can find a '56 or later flywheel and the starter that goes with it. You need a 12v coil and the normal conversion changes to the car. Luckily most of the gauges are mechanical. The gas gauge can be a pain. But those are 12V issues and not GMC issues. You made a great choice for a classic inline. I've been running the 270 in my '53 pickup since '78. I am collecting parts for a supercharged 302 that my someday happen. I hope this helps.
I wish someone would write a book to up date the GMC information. A lot of new developments have occurred since the books of the early '50s. The "hay day" of the 302 came after they were written. Still the books by California Bill Fisher are a great help and can be found on eBay. Beater
 Originally Posted By: Beater of the Pack
 Originally Posted By: jalopy45 #4899
, ...hope for some ol' fart like Beater \:D to chime in ...

OK, I'll answer to that. I became a grandfather yesterday!



Congrats... only 23 more and then you can appreciate my Christmas List.
Posted By: 50 GMC Re: Need help planning my GMC 302 install - 12/14/13 12:09 AM
Your best bet is to find a 228 complete with the oil pan, front timing plate and oil pump. You might also see if you can get a working vacuum advance and distributor from the smaller 228. Would be good to get the small bell housing as well . . . the bell housing on a COE motor is a boat anchor.

While you have it apart, consider a full flow oil conversion as well.

All 302's have a six bolt flywheel. The flywheel on the COE motor is likely a large diameter recessed unit . . . another boat anchor. You will want a flywheel off a 248 or 270 with the 6 bolt pattern. As mentioned, you can make either a 12V or 6V ring gear and starter work on 12V. You will be happier with a 12V system when it comes to options for an ignition system.

The Nicson cast exhaust manifolds are a great fit and the Nicson dual carb intakes work well too.

Even with the small 228 oil pan (8 quarts) you may still need to section and weld it to get it to clear your front suspension. You will likely have a little creative work to get the rear motor mounts to work as well.

If you got the updraft intake / exhaust combo, keep this for trade bait as it is worth comparably more than a standard intake to the right guys.

Sounds like a fun project.
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