Chevy 366 Big Block ?s: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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June 10, 2011 8:56 a.m. RossD SuperDork

My dad and I are going to look at a 1/2 ton chevy pickup with a Chevy 366 big block engine in it.

http://appleton.craigslist.org/cto/2429449358.html

Does anyone have any working knowledge of the 366 cid BBC? I know they are a medium duty truck engine (dump truck, wrecker...) but I was wondering how it would do in a truck like this? Any performance parts available? Any parts at all at the local parts stores?

Any other useful information for when we go and look at it?

This truck would be used to go up north, go down logging trails and other pickup truck duty type things (i.e. not a daily driver).

Thanks in advance, Ross
June 10, 2011 9:04 a.m. tuna55 SuperDork

If I remember from a while back, it has a taller deck and really tall pistons. If you spent some time, you could build a high cube stroker out of it with new rods and pistons.
June 10, 2011 9:19 a.m. pres589 Dork

Yeah, if you want to spend some money on a custom rotator assembly, the 366 seems like a decent block to start with. Throw away everything else save for the crank and start over. Something else to consider; swap headers for a 396 or 402 or 454 for the platform you are considering may not work well with the taller deck. Possibly consider "ram's horns" exhaust manifolds or similar with their center vertical dump so you can just change the downpipe instead of trying to tweak tubular headers to work. Or this may actually be a non-issue, but I think it may be worth considering.

Heads are probably garbage but I'm sure that there's an aftermarket alum. version just waiting on a shelf somewhere.

I'd probably just get a 5.3 LS type V8 myself.
June 10, 2011 9:24 a.m. RossD SuperDork

I've been talking with my dad and he said the guy just had it rebuilt. It's already in the truck but if something does rear its ugly head my dad said that he'd just swap in a junyard 350.

The fun thing is I know how my dad operates and that 'junkyard 350' could turn into a LSx
June 10, 2011 9:50 a.m. Ranger50 HalfDork

10.2" deck vs the original 9.8" deck. 4 ring pistons vs 3.

Good start to building a stroker motor that doesn't have oodles of thrust issues.
June 10, 2011 3:23 p.m. novaderrik Dork

a 366 was designed for heavy duty trucks and busses, so they are designed for making low end torque.

really small bore, with the stroke of a 396/427. the crank is forged.

4 bolt mains- a lot of those engines had their main caps stolen to be put on a 2 bolt 454 block.

crappy heads, but those are easily swapped. but i don't think there are any good heads that would work with that tiny bore.

not much available for intakes, but there are spacers out there to use regular big block intakes.

the distributor is also different than a regular Chev V8 distributor, but some high end units have an adjustable collar for use on the tall decks.
June 10, 2011 11:15 p.m. curtis73 Dork

The 427T is not a bad starting point for a nice stroker given its larger bore. The 366T is darn near useless. small bores, heavy rotating assembly, lack of cheap intakes.

If you buy the truck, I would price it as a truck without an engine. You'll be yanking that 366 really soon. Heavier than a regular BBC, no more cubes than an SBC, and choked to about 3500 rpm.

Think of it like a 350 that makes less power than a 305 but weighs as much as a diesel and you won't be disappointed.
June 11, 2011 8:51 a.m. iceracer Dork

366- lots of torque, not much horsepower. quite heavy as I recall.
June 11, 2011 10:34 a.m. mad_machine SuperDork

that's it.. I have driven a box truck with the 366.. it's great for hauling EVERYTHING you can throw at it.. just do not expect it to rev.

A side effect.. it was better on Gas than the box truck we had with the 429.. while ony about 3mpg.. that is a considerable amount in a truck with all the aerodynamics of a house (house might have better aero)