That one is listed as a Bowtie block so it's probably over the counter.

From Motec and others:

460778.....305...78-79...2 or 4, some Canadian assembled heavy duty truck blocks have 4-bolt main caps.


http://www.1968ss.com/sbcnumbers.asp

361979..305-77-79...2 or 4: Some Canadian assembled heavy duty blocks have 4-bolt main caps

I've been looking for something like the way some sites list the 460778 or 361979

Guys claim the 454 Truck was low deck and that's what I'm trying to establish.

I've personally saw one 305 4 bolt block that was in an approx 1978-79 Monte Carlo.

Thanks
Randy

I know you're not nuts!!

Just trying to find some verification source.

Thanks
Tandy

GLHS60 wrote:

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seventy2plus2 wrote:

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This thread is talking about a 366T engine. Dumb question, is there a difference between a 366 and a 366T engine?

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I see some are up earlier than me!!  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 

There are no dumb questions.

As far as we're concerned there really isnt any difference.

All 366, no 396, many 427 and possibly some 454 Engines were Tall Deck and received the a T designation. 

Tall Deck Engines were workhorses that came mostly in Med Duty Trucks, not pickups.

In a nutshell, there were no non Tall Deck 366 Engines.

There were 454 Truck Engines but I've found no proof they were Tall Deck.

Would love to see some evidence showing the approx 1980 454 Med Duty was a Tall Deck.

There are some later Tall Decks as well, both OEM and aftermarket.

 

Thanks

Randy

-- Edited by GLHS60 on Monday 8th of April 2019 09:11:32 AM

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    There is a 454 tall deck 4 bolt gen 5. casting #10134366 and # 14044807 

This is an interesting topic & I don't know how I missed it up to now. I did not know about the gear drive for the camshaft on these engines, and that is despite still having the Chevrolet truck brochures that I have had since 1969/70.

The Chevy inline sixes already used gear drive for the cam because they were conceived as low-revving engines with low valve-train loads. As for the Mk IV we typically think of them as high performance, but on a truck you need low revving bottom end torque for longevity & economy. Between the low revving nature of these engines & associated lighter valve spring pressures with a mild cam, the engineers probably felt comfortable in using the gear drive. With a gear drive you only have a small contact area to spread out the load vs. a chain drive that distributes the load across half the sprocket. Also the noise level could be a little higher with a gear drive (especially with steel gears), but when all your truck transmissions whine like rock crushers & the inside of the cab sounds like an all-day-explosion, it is a moot point.

Below is a single page from the 1966 Chevrolet Truck Engineering Features brochure in which I underscored the passage about utilizing a gear drive for the cam.

On the page above, no doubt they are comparing the 348 "W" motor to the 366 Mark IV motor. The 348 was gone after 1961 from passenger cars but stayed in production on medium duty Chevy & Canadian GMC trucks through 1965.

After dropping the 409 from the big trucks after 1965, the 366 was the biggest gas V8 engine in the trucks through 1967 before the 427 was added for 1968.

The tall deck 454 was used for only a year or maybe 3. Either way, a rare find. The block for a tall deck 454 Medium Duty truck engine really should be the same block as the 427, they just needed to throw a longer stroke crank in it to make a 454 out of it. If it was like the passenger 454 then it also would have been externally balanced.

Back in '79 my brother came home driving a brand new C60 furniture van for Patterson's with a 366. I also remember a new 1974 Tilt Cab T60 with 366 badges being used by the Art Shoppe, an exclusive furniture store in downtown Toronto.

It must be the auto-correct. Sure, that's it! Spelling "Engine"  M - o - t - o -r 

It wouldn't do for the old Esso slogan to say, "Happy Engining"

You can drive on a Parkway and park on a Driveway.

The Chevy sixes used a fiber cam gear to keep the noise down (mine runs silently) but the fiber gear is no good for high-revving, high valve load, high performance applications. That is why my "built" six on the engine stand has steel gears.