anybody know about the 366?

[chevyfan87]

im assuming that the 366 big block wont bolt up to a 700r4? and your all going to call me stupid for even mentioning that motor in the first place... found one on CL with everything(accesories and all) for "best offer" so it just made me curious

[2COR517]

Why do you have a bunch of trucks you sold listed in your signature? Are you a dealer?

[chevyfan87]

no dude. just few of the FSC trucks ive had. the 91 isnt sold... and isnt for sale.

[someotherguy]

366 has a regular bolt pattern on it, 700R4 should bolt up fine, but I don't know why you'd bother. It's a fairly gutless commercial engine typically used in older heavy trucks, above 1 ton, nothing to get excited about at all. I'd skip it.

Richard

[Badass69]

2 words for a 366, boat anchor. Next to nothing for power and fuel mileage in the single digits.

It will bolt up but you will obviously need a corresponding flex plate to match it off a passenger car engine like a 396/402 or 427. Basically an internal balance big block.

I have more firsthand experience with them than probably 95% of this board and the above recommendation from Richard is a valid one. There is a reason the guy is basically giving it away, because it's worthless.

[chevyfan87]

well i dint know if there was anything useful to do with it.

i know its not a powerhouse but in stock configuration the are supposed to be pushin 235hp 345tq. and i know a cam for a 454 would fit... and id be able to say "i have a big block"...even if its a lil one\

but i imagine im looking at alot owork swapping one in. i dont suppose the motor mount would be the same? i wantto find out as much as possible but nobody seems to know.

[Badass69]

I don't know where you got that horsepower and torque figure from. Maybe it's a gross number from back in the 60's. A 454 in the mid to late 70's and then the 80's had about those exact numbers. And a 1970 Chassis manual verifies your numbers. Gross Hp. So real world, maybe 180 Hp and 290 lb ft.... less than a stock TBI 350.

[2COR517]

The old timers are as polarized about 366 vs 427 in a heavy truck as we are about Ford vs Chevy.

[454cid]

I've wanted to have a 366 for awhile. I've heard guys say they are super reliable and like them, and I've heard guys say they've got no power and hate them. I figure that even if they don't make much power that they can't be too bad in a lighter truck, even if they are underpowered for a dump/grain truck.

[someotherguy]

I think the point is that you can make the same/more power easily and far more economically with a 350, and it still be totally reliable.

Richard

[ryan_thompson87]

I think the point is that you can make the same/more power easily and far more economically with a 350, and it still be totally reliable.

Richard

Exactly.

I do however know a guy who runs one in a beat 81/82 Suburban on 37s and actually goes pretty good.

[454cid]

I think the point is that you can make the same/more power easily and far more economically with a 350, and it still be totally reliable.

Richard

I think if that were true then GM would have simply used the 350 in all the heavy trucks/busses then, and not bothered with another engine. Keep in mind that if I had a 366 it would be kept mostly stock. I'm not talking about trying to build a drag racing engine out of one. I assume the OP is thinking something similar.

[someotherguy]

I'm sure in the heavier trucks they had better longevity. But in a light truck...no advantage.

Richard

[Badass69]

They are a heavy duty overbuilt engine. Now quite a few 2 and 3 tons had 350's in them as well but they were strangled with pathetic heads/cam and 2 barrel carb so they were even more gutless in the original applications. The point being conveyed is in todays day and age swapping a 366 into anything is a complete waste of time as the average smogger 350 can easily make the power and torque a 366 does, eat less fuel and weigh a lot less doing it.

The 366 liked to overheat a lot, oddly enough and as with it's 427 counterpart melt pistons. That's of course in a loaded heavy duty truck though and not a pickup.

Any average 350 can do better than a 366 and last just as long or longer doing it in a light duty truck......

Last one I got was for $25 and it was low mile sitting on a pallet, complete carb to pan. I yanked the crank out of it and sold it ( they are forged and worth at least a $100 as a core to the 396/427 crowd) and hauled the rest of it to the dump.

[ryan_thompson87]

They are a heavy duty overbuilt engine. Now quite a few 2 and 3 tons had 350's in them as well but they were strangled with pathetic heads/cam and 2 barrel carb so they were even more gutless in the original applications. The point being conveyed is in todays day and age swapping a 366 into anything is a complete waste of time as the average smogger 350 can easily make the power and torque a 366 does, eat less fuel and weigh a lot less doing it.

The 366 liked to overheat a lot, oddly enough and as with it's 427 counterpart melt pistons. That's of course in a loaded heavy duty truck though and not a pickup.

Any average 350 can do better than a 366 and last just as long or longer doing it in a light duty truck......

Speaking of which I've seen the manifolds glow cherry red on these trucks more than once

[Badass69]

Speaking of which I've seen the manifolds glow cherry red on these trucks more than once

Me too, hence why they crack and it's hard to find good clean 366/427 truck exhaust manifolds that are still in one piece.

[454cid]

The 366 liked to overheat a lot, oddly enough and as with it's 427 counterpart melt pistons. That's of course in a loaded heavy duty truck though and not a pickup.

So what makes the 366 so different than the 454 then? I can't see how the 366 is such a bad engine when it's built heavier than a 454, and better oil control at the pistons (I assume since it has an extra ring). The 454 is a much loved engine, yet almost everyone yells "junk", or "boat anchor" at the mention of the 366. To me that's like saying Mountain Dew in the 1 Liter bottle tastes great, but tastes gross out of 20oz bottle.

Last one I got was for $25 and it was low mile sitting on a pallet, complete carb to pan. I yanked the crank out of it and sold it ( they are forged and worth at least a $100 as a core to the 396/427 crowd) and hauled the rest of it to the dump.

$25??? I've never seen any engine advertised for double that. I've checked 366 prices the and cheapest I've seen are in the hundreds....... of course that doesn't mean the engine sells.

I hope you mean the junkyard, and not the dump. The dump is for old pizza boxes and the Styrofoam trays meat comes packed in.

[Badass69]

So what makes the 366 so different than the 454 then? I can't see how the 366 is such a bad engine when it's built heavier than a 454, and better oil control at the pistons (I assume since it has an extra ring). The 454 is a much loved engine, yet almost everyone yells "junk", or "boat anchor" at the mention of the 366. To me that's like saying Mountain Dew in the 1 Liter bottle tastes great, but tastes gross out of 20oz bottle.



$25??? I've never seen any engine advertised for double that. I've checked 366 prices the and cheapest I've seen are in the hundreds....... of course that doesn't mean the engine sells. I hope you mean the junkyard, and not the dump. The dump is for old pizza boxes and the Styrofoam trays meat comes packed in.

Nope I meant dump..... like where you haul your old pizza boxes. I just tossed it in with the rest of the scrap metal at the place. They run a taller piston with an extra compression ring, nothing to do with oil control.


And yes $25, less than a decent meal. Probably would have ran great if I would have put it in something. Had zero ridge on the cylinder walls and the bearings were in perfect shape.


What you don't seem to understand ( you again have never driven or owned one as I remember) is it's a puny useless underpowered engine. So honestly man, why must you defend something you know absolutely nothing about? Yes I hate them, but then again owning and driving them any amount does that to a person.

I mean I am not in any way stopping you from buying one, so go hard, get one and use it for whatever you choose. You seem to think one might work for you so what's holding you back? Hell swap the 454 out of your truck and dump a 366 in there. I am sure an L29 454 would sell for a lot more than what a low mile 366 would cost.

Real world they were just too small to do anything and then still suffered from any other regular big blocks short falls. It has no power, lacks cubic inches to do much of anything and is all in a heavier than a passenger car big block package. Any run of the mill 350 you can get, even the Goodwrench one with old 80's smogger style heads, will embarass one in a pulling package.

No I won't debate with you anymore about them until you actually go and get some experience with at least a couple before you constantly defend one to death. Just because it came in something with a GM badge on it doesn't automatically make it wonderful.

[Fast305]

Its basically a 283/307 bore in a big block with 4 piston rings per piston. The stock heads flow horrible, result in horrible CR, and the stock cam is tiny. However the argument that it last better than a 350, you have to be joking right. With 4 rings per cylinder they run and run and run, even in the HD applications. I have riden in 66 passenger school buses with the 366/allison setup. Our coaches put the pedal to the floor into the 4bbl holley and passed just about everything but a gas station. I can remember riding in a bus driven by a coach that drove very aggressively and gunned that thing up to atleast 75-80 mph running late to an out of town game. The real turd is the 8.2 Turbo Diesel.

[Badass69]

Its basically a 283/307 bore in a big block with 4 piston rings per piston. The stock heads flow horrible, result in horrible CR, and the stock cam is tiny. However the argument that it last better than a 350, you have to be joking right. With 4 rings per cylinder they run and run and run, even in the HD applications. I have riden in 66 passenger school buses with the 366/allison setup. Our coaches put the pedal to the floor into the 4bbl holley and passed just about everything but a gas station. I can remember riding in a bus driven by a coach that drove very aggressively and would that thing up to atleast 75-80 mph running late to an out of town game. The real turd is the 8.2 Turbo Diesel.

Buses have didley squat for weight on them. A truck carrying even 4 tons of fertilizer or grain makes 66 passengers look like a complete joke. They run, yes they run. They will be a sad sorry excuse of an engine their entire life but they will run......... then melt a piston, lol The 427 should have been the base engine for a lot of trucks, and left the 366's for the passenger world crowd......