[RocktimusPryme]

Im curious what the group thinks about the heavyweight vehicles and the need for large displacement engines.

As noted in other threads I recently picked up a pair of 1962 Catalina Safari wagons. One of which is a runner and pretty close to being road worthy. The problem is someone put an Olds 455 in it. This drives me nuts. It breaks my rule for engine swaps. A swap needs to be able to be argued as an improvement. A newer LS-style engine can be argued as a technological improvement. Everyone doesn't have to agree but it's a defensible position. Going from a Pontiac V8 to an olds V8 is at best sideways. (IMO its actually backwards) Not defensible as an improvement.

The olds does run, and run decently for a gutless 70s smog motor. So I have time to work on other things, plan a route and wait for a good deal.

Because the Pontiac mounts were removed I am considering going said LS route. But I probably won't. I will probably weld Pontiac mounts back in and go that way. I would really like to have an excuse to use a tripower.

Because I have time I am mostly content to wait on a 400 or bigger deal to come along. But there are lots of 350s out there for pretty good deals. The big ole wagon comes in at over 4000 lbs. Should that preclude me from choosing any engine under 400 ci? Would a 350 for something I dont have any real performance aspirations other than doing a burnout be plenty? Would a larger motor actually be a waste of money for something I dont intend to be fast? I want a little pep, I am a performance enthusiast after all, but I know this thing isn't going to set any 1/4 mile records.

I know there are some long held beliefs that for the big boats the larger displacements engines are actually more efficient. But then again the 5.3 gets put in all sorts of trucks that are probably heavier than my wagon. Is that just modern technology overcoming, or is that old belief about heavy cars and huge displacement flawed to begin with.

[kingbuzzo]

With the price of fuel taken into consideration that may damper a larger displacement yet again at 4000 maybe a 350 would have to work harder?

[RocktimusPryme]

Yeah thats been an argument that a larger engine will actually get better fuel mileage with a heavy vehicle. If that's an internet fact or an actual fact I don't know. And where would the line be? Not sure.

[JSchmitz]

I've always felt that displacement is king on the street (normally aspirated). This is especially true in heavy vehicles. On the track, you can make just about all cubic inch engines fast.

[JLMounce]

I think it really depends on what you're after for the vehicle. My wife's Chevelle had a GM Goodwrench 350 crate motor with an edelbrock intake and headers. These are about 250hp and maybe 300 lb ft of torque. Had a 3.42 gear and a TH400. Even up here in the thin air of Colorado, I never wanted for power in that vehicle. Was it fast? Absolutely not, was it still fun to roll around in and have a good time? You bet!

If the car is something to enjoy that sounds decent and has enough to not make the car feel like it's a slouch, I don't see anything wrong with the smaller displacement engines. If you want to run a tri-power that does to an extent limit your upward power potential anyway. I wouldn't scoff at a P350 in there, especially if it was built near an HO variant.

[george kujanski]

I have a 5.3 in a Tahoe and it seems to be gutless below 2000 RPM.unfortunately the Trans is programmed to go into 6th too early so it's downshifting at the smallest hill. Annoying.
My 455 still has torque at 30 mph in 4th

George

[b-man]

Stick an inexpensive running Pontiac 350 in it without hesitation. If a running 400 comes along use that, but there’s nothing wrong with a 350 which has about the same power as most of the 2-barrel 389s that came standard in the ‘66 big Pontiacs.

The 350 is just a 389 with a smaller bore and a better cylinder head design, that 3.75” crankshaft gives the 350 (354 std. bore or 360 bored +.030) great low end torque characteristics compared to a SBC 350.

[Scarebird]

I think it depends on what you want this wagon to do.

Unless the mileage is truly horrifying why not keep the Olds? It seems to do the job and is already there.

[RocktimusPryme]

To be clear I wouldnt stab a totally stock mid 70s era 350 in. I said I wasn't looking for speed in this project, but I also just don't have it in me to only have 230 HP. But good running engines are just so cheap in some cases that you can save a ton of money by putting some better heads on a 350P shortblock compared to a 400+ CI engine where you would often be paying more for a core block that needs machine work and all the parts than you would for a decent running 350P complete engine.

If I did it I would probably use some heads to raise the compression and try to make sure I located a block that had the chamfers in the block to run larger valves and a medium cam. I feel like 320-350 HP with a 350P would be pretty attainable with large valve heads and a cam. Am I crazy there?

Sound good, do a burnout, and have enough when you put your foot down to feel fun. Maybe run a high 14.

I do want to know how the group feels about economy just out of curiosity. Does anyone feel that a smaller displacement 350P would get worse mileage than the 455 olds?

[RocktimusPryme]

Originally Posted by Scarebird

I think it depends on what you want this wagon to do.

Unless the mileage is truly horrifying why not keep the Olds? It seems to do the job and is already there.

One, it just bothers me. I know there are Olds fans and that's fine, but of all the BOP engines I have the least respect for the Olds platform.

Two, even amongst Olds 455s, this is a junk one. I tried to stab it in the driveway last night and was disappointed. It barely spun the tires on grass. Though to be fair I haven't looked at the timing. It has J heads, which when I looked up Olds heads the article I found opened with "Remember J is for junk" If it wasn't the doggiest of dogs smog motor, I would be more inclined to live with it. Maybe there is a case for putting better heads on the olds, but man opening the hood and seeing that motor in there just bothers me.

Now where I am inclined to agree with you some is the geometry of it all. That part of the swap was actually done pretty well. Im not sure hold the big olds compares to a pontiac block on dimensions in relation to the mount points. But I would guess the engine is both forward a little and down. Because the HEI clears by a ton, which isn't always the case. And it has a Th400 cased TH375 in place of the slimjim which everyone says wont fit.

So if I do go back pontiac, or LS or whatever. Rather than trying to weld factory mounting tabs back on I might just weld in some 75-81 T/A frame mounts similar to how the olds is in there to keep it on the same plane and not have to move the trans crossmember. Im curious if it has shaft vibration. I haven't gotten it over about 30 MPH yet.

[1968GTO421]

Originally Posted by RocktimusPryme

To be clear I wouldnt stab a totally stock mid 70s era 350 in. I said I wasn't looking for speed in this project, but I also just don't have it in me to only have 230 HP. But good running engines are just so cheap in some cases that you can save a ton of money by putting some better heads on a 350P shortblock compared to a 400+ CI engine where you would often be paying more for a core block that needs machine work and all the parts than you would for a decent running 350P complete engine.

If I did it I would probably use some heads to raise the compression and try to make sure I located a block that had the chamfers in the block to run larger valves and a medium cam. I feel like 320-350 HP with a 350P would be pretty attainable with large valve heads and a cam. Am I crazy there?

Sound good, do a burnout, and have enough when you put your foot down to feel fun. Maybe run a high 14.

I do want to know how the group feels about economy just out of curiosity. Does anyone feel that a smaller displacement 350P would get worse mileage than the 455 olds?

I feel that it is all a matter of optimal tuning and engine condition. Based on what info you've given I think the 350P would do very well on mileage over the current Olds 455. FWIW

[b-man]

Don’t be thinking big valves are needed for a 350, the stock ‘68 -‘70 350 heads with 1.96/1.66 valves are better suited for a torque engine and won’t give anything away in upper-RPM performance when you need passing power.

The ‘69 #46 400/428 heads are a very nice 350 head and have the same small valves as the early 350 heads with a smaller 72cc advertised combustion chamber (probably around 75cc) for a nice 9:1 compression ratio when swapped onto a 350.

I’d say a well thought out 350 with a torque producing cam like the factory 066 (1968 350 HO auto transmission cam) or perhaps the Summit 2800 or Crower 60240 would be the ticket. Run the stock log exhaust manifolds, some nice 2-1/2” PYPES downpipes and whatever free-flowing exhaust you like.

Don’t be expecting anywhere near nor aim to build a station wagon 350 for 350 hp, even 320 is more than plenty which was the factory rating for the small-valve ‘68 350 HO. A solid 300 hp will get you there which would be roughly equivalent to a ‘68 350 HO with the compression dropped down about one point to 9:1.

[Dragncar]

Wait for a Pontiac 455 runner to come along. They are still out there and one of those wonderful engines belong in that car.

[Formulajones]

Originally Posted by RocktimusPryme

Im curious what the group thinks about the heavyweight vehicles and the need for large displacement engines.

As noted in other threads I recently picked up a pair of 1962 Catalina Safari wagons. One of which is a runner and pretty close to being road worthy. The problem is someone put an Olds 455 in it. This drives me nuts. It breaks my rule for engine swaps. A swap needs to be able to be argued as an improvement. A newer LS-style engine can be argued as a technological improvement. Everyone doesn't have to agree but it's a defensible position. Going from a Pontiac V8 to an olds V8 is at best sideways. (IMO its actually backwards) Not defensible as an improvement.

The olds does run, and run decently for a gutless 70s smog motor. So I have time to work on other things, plan a route and wait for a good deal.

Because the Pontiac mounts were removed I am considering going said LS route. But I probably won't. I will probably weld Pontiac mounts back in and go that way. I would really like to have an excuse to use a tripower.

Because I have time I am mostly content to wait on a 400 or bigger deal to come along. But there are lots of 350s out there for pretty good deals. The big ole wagon comes in at over 4000 lbs. Should that preclude me from choosing any engine under 400 ci? Would a 350 for something I dont have any real performance aspirations other than doing a burnout be plenty? Would a larger motor actually be a waste of money for something I dont intend to be fast? I want a little pep, I am a performance enthusiast after all, but I know this thing isn't going to set any 1/4 mile records.

I know there are some long held beliefs that for the big boats the larger displacements engines are actually more efficient. But then again the 5.3 gets put in all sorts of trucks that are probably heavier than my wagon. Is that just modern technology overcoming, or is that old belief about heavy cars and huge displacement flawed to begin with.

You could get respectable mileage out of that olds 455 with the right combo of parts if you wanted to, or about any engine you want to put in there for that matter, but it's going to cost a bit to get there.

Overdrive would be the first big step in that direction. Getting the cruise rpm down in a reasonable range is everything when it comes to MPG. Generally 3-4 mpg gain with just the addition of an overdrive gear is pretty typical. From there it's a matter of fine tuning the engine and optimizing the whole package.

If it were mine, as long as that 455 Olds is running fine, not burning oil, doesn't make funny noises, I'd just leave it in there. Doing another engine to swap in is just added cost and potentially more problems to deal with, as most swaps tend to do (accessories, mounts, trans compatability etc...). I'd just refine what's there, add an overdrive, and enjoy the car as is. Spend money in other places where it's needed most. I'd be waiting for that engine to give me a good reason to pull it out.

[694.1]

See post 7.

[Scarebird]

Originally Posted by Formulajones

...Spend money in other places where it's needed most. I'd be waiting for that engine to give me a good reason to pull it out.

Truer words rarely spoken.

If you are truly thinking LS think bigger: LT architecture. 2014 and newer with direct injection and VVT. LT 5.3's are currently cheaper than their older LS brethren with far less mileage and better power/efficiency. Most challenging thing is the management ECU. Were I to do this again I would bite the fiscal bullet and use the Holley setup with a TH4L80E; 5 of 6 bellhousing bolts would fit.

[RocktimusPryme]

Originally Posted by Formulajones

I'd be waiting for that engine to give me a good reason to pull it out.

This is the last straw!!!

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.


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.

I have long thought that people who don’t plan on a lot of power should use the 557 blocks and save the other 400s for people that need them.

[b-man]

Make an offer and then make a road trip out to Ventura CA to grab this running 400:

https://forums.maxperformanceinc.com...d.php?t=862467

Well it is kinda far away from Indiana but you get the idea. Weather is nice right now in CA, vacation time!

I’d get that ugly gas guzzling Olds 455 out of there in a heartbeat. The Pontiac 400 is the best combo for both fuel mileage and power.

You could probably break even after you unload that Olds 455. A Tri-Power would look sweet on that 400 engine too.

[phil400]

You could probably sell that 455 to Olds guys which would offset the cost of getting a Pontiac in it, a re-ringed 557 with some #46 High comp heads and a summit 2800 as already mentioned would be a real torque engine which is what will get that big wagon moving. Jmho.

[Tom Vaught]

Originally Posted by b-man

Make an offer and then make a road trip out to Ventura CA to grab this running 400:

https://forums.maxperformanceinc.com...d.php?t=862467

Well it is kinda far away from Indiana but you get the idea. Weather is nice right now in CA, vacation time!

I’d get that ugly gas guzzling Olds 455 out of there in a heartbeat. The Pontiac 400 is the best combo for both fuel mileage and power.

You could probably break even after you unload that Olds 455. A Tri-Power would look sweet on that 400 engine too.

X2

Tom V.