Allan R

What are the significant differences between the 350 L32 and L34 other than intake manifold and carbs?

Allan R

Bump
I can't believe no one here knows this....

BlackGold

What is this L32 and L34 of which you speak? Enlighten us.

I'll answer assuming that you are talking about the L74 engine as opposed to the standard 350, and I'll assume you're asking about 1970. (Maybe I'm assuming too much.)

The standard 350 was rated at 250 HP, burned regular fuel, had a 2 bbl carb, and always had single exhaust.

The L74 350 was rated at 310 HP, was high-compression (so liked premium fuel), had a 4 bbl carb, and could be ordered with either single or dual exhaust.

Looking at the engine assembly manual, I see that the L74 used the exact same camshaft but used a different carb different intake manifold, different pistons, different distributor, and different plugs. Everything else was the same.

The L74 option was the QV, QN, or QP coded engine, depending on whether you ordered a manual or automatic and whether or not you ordered A/C.

Part way through the 1970 model year, a new QB code engine replaced the QV code for manual transmission cars. Of course, the public never knew this happened; it was all just option L74 to us. There's more little differences, but basically the new QB code engine used a hotter cam and richer carb.

One more interesting note: Above I said that "everything else was the same." Actually, that's not true. Believe it or not, the L74 engines used different bearings than the standard 350. I don't know the specifics; all I can assume is that Olds engineers wanted to use higher quality or slightly looser bearings in the engines which were capable of spinning faster.

Allan R

No, Actually I'm talking about the 1972 Cutlass model year, and the 350 engines. The engine code for an L32 was H and the L34 was M. On a basic level the main differences I can see (and I'm open to whatever else you might know) is that the 350 came as a 2bbl (L32) or a 4bbl (L34). What I'm trying to find out is whether there was a different cam & crank for the different engines. I recently changed my car from 2 bbl to 4 bbl. It's due for an engine rebuild soon because compression is down (although it doesn't use a lot of oil or smoke) and the seals are starting to leak quite a bit. The info about difference between L32 and L34 are basically to determine what I need to spec into my rebuild. I was going to go with a 455, but my project block is too severely cracked to continue. So I decided to spend the money on the 350 that came in the car.

ah64pilot

I found this and decided that there should NOT be an unanswered Allan thread on the CO website. Here it is from my build thread...the AMA documents for the 1972 model year have the 350 2 BBL and 350 4 BBL Automatic Transmission engines sharing the same camshaft.

Running duration 250 / 264
Lift .400 / .400

All other aspects are the same, crank, rods, pistons, heads. You will be ok restoring that 350 to spec as both engines have the same specs all around aside from the intake manifold and carburetor. There is only a 20 HP difference (160 & 180 respectively) and the same torque.

http://wildaboutcarsonline.com/membe...ss_Supreme.pdf

My question is...why can't you find another 455 to build? If that's what you really want to do then why shortcut it for a few hundred bucks? Shoot...I am going to get a 1971 455 and TH400 from Texas_Jim for $300. And it runs...couldn't you go that route? All I'm gonna do is trick it out and ruin it for a cruising motor...if you wanted it would it cost very much to ship?

Allan R

Thx Steve,
I have been thinking about this for a while. The 455/400's up here aren't as plentiful as down your way. And folks want $$$$ for them even if they don't run. Most that come on the market are 73 or later.

The main reason I wanted to know about the 350? My car still has its original engine/trans. It started life as a 2bbl, and I changed it over to a 4bbl without touching the cam. It needs a rebuild, and the toss up was whether to keep it a matching block/trans to the VIN or drop in a 455/400 for the torque/performance. Although I love your silver car, you know I'm not gonna build mine as a track car, so prolly a rebuild on the stock 350 with a mild cam, better intake, headers to give it the kind of punch that it really should have. Oh, changing the rear to 3:23's also from the stock 2:73s

So that ^^ is why I was wondering about the difference. It looks a lot to me like L32 just had lower HP due to 2bbl carb compared to the L34 4bbl. Thanks again!

Tony72Cutlass'S'

Al,

I'm proud of my 350, i thought alot about building a sexy 455 from the ground up.

Realistically, i'm going to freshen up my 350 with really nice components, built for longevity, rather than performance.

Allan R

Don't get me wrong Tony, I love my 350 too! It will be a nice engine when I'm done. But if a 455/400 combo comes along for the right price I think it would be silly of me to pass it up. I've had a 455 before and it was an awesome engine. Little hard on gas, but my 72 won't be a DD.

GAOldsman

Allan the internals look the same as it only put out 20 hp less than the L34 with the same 275 ft lbs of torque. The L32 came standard with the F-85, Cutlass and Cutlass S as it was a $33.00 credit for the Cutlass Supremes. Also the L32 wasn't available if you wanted a TH400 or M20 4-speed or bought it in Cali and wished to have a standard shift transmission. There is a 1 quart coolant capacity difference between the two engines and the cam is the same on the automatics but different for manual trans and even different yet for the L34 with manual trans.

ah64pilot

Allan, I dropped a big hint in my last post...did you miss it? It was something like I'm going to buy a 455/TH400 from Texas_Jim for $300...but more to the point...do you want it?

It cost the same to build either engine...I'd hate to think that $300 + shipping would keep you from having a 455. As you well know, it is so nice to nudge the throttle to enter a freeway than to step on the gas and downshift to get up to speed

Allan R

Steve - uh, I really did miss that hint. Tell you what. I'll send you a PM with my address. Can you find out what the shipping on that would be and LMK? I'd bet ya a case of cold brewskies it's way more than 300.00 to ship. The shipping price would put it in line with the 455/400's guys up here are selling for around 700.00 - 1000.00. But yours is a 71 and all these are 73 and newer

PM on the way.

ah64pilot

So I'm thinking you need to plan a road trip to Texas and come visit You can pick one up when you come lol! $700 or so to ship it on a pallet, dang!

Allan R

You're on my list of people to visit when I eventually do the road trip. Swing south through the west coast, across to TX, up through OH to QC and ONT to see some of the guys there too, then back west through the upper states to prolly the Coutts crossing. Now THAT's a road trip. Haven't mapped out the mileage yet, but I'm betting it's gonna be a LOT!

joesw31

Good running 455's are hard to find, however, if you do go with one just be sure the core is good. As Steve said this 455 is running. Or you could build your original 350 engine with some nice parts and still have a nice cruiser.

Allan R

Thx Joe. I learned that the hard way last year. From now on before I buy a 455 that doesn't want to turn, I'll pull the heads and look there first. I'll give it some time before I make the decision. Ideally I'd like to build BOTH motors. How's that for weird?

captjim

First off, IMO all HP/TQ figures should be taken with a grain. The 72 engines all came with a large dish piston (23 cc), so compression is low. If you rebuild it and change pistons, it really doesn't matter, do whatever you want, Cr can go near 10 to 1. If you re-ring, you will be limited in camshaft choice due to the low CR.

350 can be built to be fun and responsive even in a heavy car, the combo just needs to be well thought out. But it won't match the 500 ft/lbs of a BBO.

ah64pilot

Harumph! 455! Harumph!

Allan R

Steve?? Not looking for quite that lumpy a cam. The search will continue......