[Formulajones]

Originally Posted by RocktimusPryme

In all seriousness that is my general plan. The car needs other things and this engine while running gives me the time to focus on those. And the mileage thing was mostly just about conversation. I know it’s been said that in heavy vehicles the larger engines will actually increase mpg over a small engine. A dubious claim I feel. This engine likely needs some things too. The moment I have to invest money in it will be the end.


.

That's what I would suggest. Run it till it don't anymore

I'm in the same dilemma with a customer. I restored his 57 T-bird several years ago. Paint, interior, pulled the drivetrain, installed an AOD 4 speed auto overdrive, changed the rear gears, put a Fast EFI system on the car, installed AC, etc.... Beautiful car that wins awards. At that time I pulled the original 312 engine down and found it had already been bored and rebuilt in the past. History and mileage is unknown but it was spotless inside, cross hatch still on cylinders and no ridge to be found. I suspect very little mileage since rebuilt. So I resealed/gasketed it and buttoned it all back up, detailed it and dropped it back in. Runs perfect.

He comes to me the other day and tells me he wants to pull the 312 out and swap in a crate 302. Wait what??? Why? He says he just wants more power. Keep in mind this thing is just a nice cruiser. He only gets it out once a month, turns on the AC and takes his wife to a show. Darn thing gets over 20 mpg too which isn't going to do any better with the swap anyway.

Plus he's going to spend $5-$6000 for a crate engine, then pay me to swap everything. They don't make a kit for this so I have to fab engine mounts, find an accessory drive that'll work with all the stuff I've added to the car for him, all for what?? The current engine runs perfect, doesn't burn oil, smooth as butter, you could put a glass of water on the hood and it wouldn't even ripple.

While I welcome the work and the money, I'm not in the business of selling something if it's not needed. I told him to leave it alone, I think he's crazy. Run the old Y-block until it gives you a reason to pull it. But that went in one ear and out the other LOL. Guess he just wants to spend money

[carcrazy]

Out with the Olds and in with the new! Myself, I drop in a good running, reasonably stock, 400 or 455 and call it a day!

[RocktimusPryme]

Tom that 400 is a good deal. Locally I would purchase that. I actually bought my Firebird out of Ventura. If I miss anything about So Cal I miss the Craigslist and Marketplace for hot rod stuff. That and idiots here think Taco Bell is good Mexican food. They don’t even have Del Taco let alone the mom and pop stuff.

[tom s]

Down to $500!Tom

[Brentco]

Originally Posted by RocktimusPryme

Another option I meant to mention but forgot is I feel this is a perfect candidate for a 557 block. The extra displacement will make it easier to hit my 300ish power goal and provide more torque. And I likely wouldn’t hit my head on the 557 blocks durability ceiling.

This is a great idea. It seems like there are usually a surplus of 557 blocks available, probably because people are paranoid about the casting. For your application a 557 block would be great and nowhere near reaching the block’s limitations (which seem like they’re often overstated, but either way it wouldn’t matter in your situation).

Personally, I wouldn’t go below a 400. The big wagon will need torque, and for torque you need the cubic inches. I know you’re not shooting for a Jim Hand special, but it sounds like you still want the wagon to have some pep in its step. I’d be concerned that unless you’re doing a real optimized build, a 350 would feel a bit anemic whenever you step on the pedal. Especially coming from a 455, even a 455 in bad shape. (And to be honest, personally I would just wait until I could get my hands on a Pontiac 455, but everyone is different).

Also, the Internet lore about a 455 getting better MPG than a 350 is almost certainly bunk. On a per-cubic-inch basis the 455 might be more efficient, but in absolute terms (which is all that matters when you’re talking about real world MPG), the 455 will always consume more gas. You have an additional 105 cubes that will always be consuming additional fuel/air. The only way a 455 could be more efficient would be if the larger engine allowed you to tune it super lean, significantly leaner than you could tune a 350. My somewhat informed guess is that even assuming the additional cubes allowed you to run the engine leaner, the fuel savings from the lean 455 still wouldn’t exceed the savings from running the smaller cubed 350. Just musing.

[i82much]

wait ... what the heck is wrong with an olds 455??!!!!!

[gtokid1968]

Anything but an LS!!!!
I have a good runing 350 Pointiac and many 400 blocks that I could part with and dont live that from you!!!
Just Saying!!!!

[b-man]

Originally Posted by i82much

wait ... what the heck is wrong with an olds 455??!!!!!

Nothing inherently wrong with one.

Except they’re fugly.

Plus the OP would like to use a Tri-Power which would really be ‘right’ on a ‘66 Pontiac. Yeah I know Olds offered a 3x2 setup for 1966 but let’s be serious, a Tri-Power Pontiac V8 is truly a thing of beauty. Even without the Tri-Power a Pontiac V8 is magnitudes more aesthetically pleasing than any modern Olds V8.

If I were the owner and didn’t mind something ugly in there I’d opt for the LS any day over that Olds.

[Jay S]

Many years ago some crazy person pulled the SBC out of my 71 Chevelle and put in a 455 Olds.

Oh wait..That was me and my brother!

I would leave the Olds in until it needed something. That might be a problem though, you may be living with it for a while, they are generally pretty dependable. Mine has been in the chevelle since 1993.

Pulling the Olds 455 out for a 350 is just wrong to me. The Olds to a Pontiac should be a easy swap though. Personally I would want a 455 or stroker (389 or 400)combo. Put an LS in it if you want, pretty boring to me compared to a multicarb Pontiac from that era IMHO. If you want something looking more era correct for now pick up an Offy dual quad intake for the olds 455 and run 2 small carbs. The olds 455 with an aluminum intake is only about 70 lbs heavier than similarly dressed SBC, they are actually the lightest of the 455 engines. If you want to see what the engine is, there are identification letters on the heads. I would imagine you have J heads, but never know, Olds had higher flowing big valve heads thru most of there production in some applications. The ID is on the top center Exhaust ports just below the valve cover.


I have 5 cars with 455 Olds engines. The least economical of the bunch is our Chevelle. It is a bigger valve 455, runs 3.23s and a TH400, it gets about 15 mpg with just over 400 HP. We have 2 375Hp (grossly over rated from the factory, closer to 340 HP) 1970 tornados, one has 30,000 miles, the other is over 100K, they get about 17 MPG, with 3.07 gears, they weigh in at nearly 5000 lbs and run upper 15s in the 1/4 mile. We have 2 McLaren M6GT replica’s with tornado 425 trans axles, one is a bone stock smog era engine, the other is built like a 69 Hurst Olds 455. Even the smog era 455 is economical too drive, and gets mid 20s for MPG. For the same compression of most smog era engines, comparing them to other V8s with similar cubes, the 455 Olds is pretty decent on economy. They would love an overdrive, and have a lot of tq off of idle. They work great in air boats that need a lot of off tq to power a prop.

The Olds 455s have 10 bolts holding each valve cover on, no valley tray, and a very tight fitting front cover, they generally are a lot easier to keep oil leaks dried up than most other V8s. With the exception of the rear main seal, they rival most modern engines for being oil leak free.

I have not really seen the gains from going smaller on CID for economy. My 77 Trans am did a best of about 14 mpg when it was stock and all original 400 4 speed car with 3.23s. It has a 4.25” crank in it now, with a lot more compression and a roller cam. Inside of the engine is very modified, and the qjet is recalibrated. But it looks exactly that same as in did when it was stock, except I added headers, it gets in the lower 20s for MPG now, and 2x as much power. It does about the same as my 2009 Hemi Challenger. My 510 CID Dodge Charger has averaged as high 23 mpg, with a 850 double pumper, 3.23s and no overdrive. Years ago we put more cam in the 510, a 4400 stall and went to 4.10 gears, it still gets in the mid teens. Similar milage to the 455 Olds in my Chevelle. My Chevelle would love and overdrive, it has a ton of low end tq. It is very possible to have bigger CID and still get good economy, OD helps a lot. I recall one gentleman’s turbocharged Pontiac getting over 20 mpg, and I think it is over 500 CID. I prefer bigger cubes for NA combos, each to their own though. Do want you want, it’s your ride.

[Dragncar]

Want to ruin the car, put a LS in it.
Find a 455, 428 and have a Pontiac at its best blast.

[steve25]

Why not keep the Olds in it for now while you search out and prepare for a Pontiac?

Spend a afternoon on the 455 by first checking for slop in the timing chain and then moving on to tuning it better.

If it needs a chain then put one in , for less then a day's work I bet you pick back up 25 lost hp and even more torque.

There not a bad engine!
My dad had one in a Tornado with its front wheel drive and granted it was a high comp motor, but with all that massive weight on the front of the car I still burned up the tires at will and got in trouble for doing such in the high school parking lot.

[RocktimusPryme]

Originally Posted by b-man

If I were the owner and didn’t mind something ugly in there I’d opt for the LS any day over that Olds.

Same, and I actually appreciate what Scarebird said about the even newer LT architecture. Something to look into. That people get oddly angry about it just makes me want to do it lol.

If the car still had its pontiac mounts it wouldn't even be a question. But since Im going to have to get the welder out anyway, thats where I start thinking about a modern swap. And honestly its less about the engine than it is about buying a complete drivetrain with an OD transmission and slamming it in. If 455 Pontiacs grew on trees that would also be a no brainer. But they don't. I like most of you would choose the bigger motor 9 times out of 10 all else being equal. So this conversation was more about trying to sell myself on a decent 350P shortblock the previous owner of the wagon has for a few hundred bucks.


With that said, there have been a few comments about keeping the Olds for a while. I thought I made that clear but maybe I didn't. I am. Having this running engine, even if its a big turd with no power allows me the freedom to spend money in other places, and just as importantly....wait for the right deal to come along. Im probably going to put the wagon on airbags, I can spend money on that for now.

I did put the olds on the timing light yesterday and was disappointed, because is at least ballpark close. I couldn't read the numbers, but it was on in the range anyway. I gotta try to get in there with a small brush and clean the timing tab.

I also did the tire to DS spin check on the big O-P 9.3 It is a limited slip which was a big win because the PHS said it didn't come with one. Looks like a 2.73 gear. Not quite 3 full turns. Which I am actually pretty happy with. Should lessen the need for OD immediately. I would have preferred a 3.08 for a tick more grunt but Im good with it.

I am going to sell some other stuff soon to help out with finances for this new project. One thought at the back of my mind has actually been about putting the 461 out of the firebird into the wagon and building a DCI engine for the Firebird. I likely will talk myself out of that for financial reasons, but I gave up my drag-n-drive project for the wagons. That is something I still really want to do at some point. I really want something in my stable that gets down near single digits.

[Mr Anonymous]

That 73-76 olds 455 wasn't exactly a barn burner, but a 455 pontiac of the same era wasn't either. Those late olds 455s are cheap. And Since the 455 was made for eight years and put in everything from cars, boats, RVs and irrigation pumps, they are comparatively plentiful versus the pontiac 455 or buick.

That being said, the J head 455 in my parents 73 clamshell Custom Cruiser wagon was able to push it to 125 mph on at least one occasion. Not sure how fast dad went in it.

[wbnapier]

If you can afford it, go with a HiPo Pontiac 400 or 455 with the tri-power you mentioned you like.

These are hot rods and it's a hobby. Maximize the fun.

I can't imagine anything cooler than a Safari with a big cube Pontiac under the hood and a multi-carb set up. That's just bad ass.

[Jay S]

Our Olds has the SBC frame to cross member engine mounts, with 66 to 72 A body Olds 455 rubber motor mounts. The frame mount are stock SBC, and are just relocated slightly. A LS has the starter, alt, and all the main wiring on the opposite side compared to the Olds and Pontiac. Pretty much get to start over on wiring. For the money and time, a Pontiac pretty much drops straight in replacing an Olds. There is no easier swap that I can think of. I don’t know what motor mounts they used on your swap, the early Pontiacs are quite a bit different. Find a set of OEM mnts and the Pontiac would just drop in.

A friend has a Pontiac in a 455 in a 4x4 pickup. He blew a head gasket the other day and one of our friend’s millennial kid’s told him to “pull that piece of junk Pontiac out and put in a LS”. Attitudes like that it is no wonder why LS swap folks get crap from people that are loyal to original engine platform’s. That rubbed me the wrong way. My friend put Cometic head gaskets in and was back on the road. His 455 is probably about 450 HP and 550 lbs of tq. He tows 15000 lbs trailers with it, beats the snot out of it daily. It is past 30K miles on it since he did the swap. The thought of a stockish 5.3 or 6.0 LS doing the same things as his 455 is currently doing was kind of funny, the loss of tq would stink. He blew the head gasket out for a reason, it has a hard life and is always tearing around with it.

When we first put the 455 in our Chevelle it ran a 13.6 ET. Basically stock with headers. That was with 2.1 60 ft times. The tq really gets the car moving quickly with very few mods, I have been as quick as a 1.78 60 ft time. Jim Hand’s 455 wagon was in the lane next to me when I ran the 1.78, he ran a 1.73. Had more top end power, but for the most part the the Olds 455 held it’s own pretty well considering it was a stock W30 except for headers.

[RocktimusPryme]

Here is a shot of how they have it mounted.

The only thing that scares me about the tripower is the carb selection. I see 64-66 setups popup semi affordable now and then ~5-800. Need rebuilt, but that's fine. But Ive also read a bunch of horror stories about buying one and finding out the carbs are incorrect and wont work. Then its just a bunch of money and a headache.

[wbnapier]

Source the carbs and manifold through one of the tri-power specialists that are talked about on this site. Purchase, restoration, and modification all from one expert. I have used both Dick B. and Mike W. for stuff.

Originally Posted by RocktimusPryme

Here is a shot of how they have it mounted.

The only thing that scares me about the tripower is the carb selection. I see 64-66 setups popup semi affordable now and then ~5-800. Need rebuilt, but that's fine. But Ive also read a bunch of horror stories about buying one and finding out the carbs are incorrect and wont work. Then its just a bunch of money and a headache.

[Jay S]

The later style 75 and newer Pontiac mounts would nearly bolt straight on to that.

[RocktimusPryme]

Originally Posted by Jay S

The later style 75 and newer Pontiac mounts would nearly bolt straight on to that.

If true, that would be a huge win for me. My experience with Pontiac to Olds is zero. When you say nearly, do you mean it could be done without having to move those frame mounts that are welded on? Because from a work standpoint, moving them a little or moving them a lot is basically the same.

I was somewhat hoping I would get lucky by using some of the 77-79 F body stuff, but Im not 100% sure how those are mounted and if it would be relevant to my situation. The engine would for sure be moved forward a few inches, compared to the factory mounting tabs that have been unfortunately cut off.

[Jay S]

In the late seventies Olds, Pontiac, Buick and Chevy were swapped back and forth quite a bit in the same chassis. All the swaps I have done that era I reused the engine mount that bolts to the cross member mount, and bought the corresponding engine mount. Sometimes the cross member mount would have to be moved to another set of holes that were already drill from the factory. That is were your car might be different, since it was welded. I think the later F and G body Pontiac mount will actually set down on those mount perch’s and be the right height. I am not sure about the fore and aft position though, i think that will be off some. It might be one of those deals that is looks very close but you have to rework it anyway. If it did work, that style mount would be a lot stronger mount than factory OEM early mount in that car, would have neoprene options on the newer style also.