Aluminum chevy 350 block

Chat with a guy tonight that say he have an old alu chevy engine. It was his fathers who was in car repair some years ago. (Also have 318 hemis and the like..) I though it was bullE36 then remember that a guy put one like that in a mid engine corvair.

Whats the story on those? I quit googling it after 1 hour of modern brand new version...

I don't think they ever came from the factory that way. There was the super rare all aluminum ZL1, but that's a 427 BBC.

ZL1 427 is the only aluminum factory block that I know of GM ever made for a production car.

In reply to Ranger50:

The Buick/Olds/Pontiac 215 was all Aluminum 1961-1963.

Also the LT5 350 in the C4 ZR1, but that had 32 valve DOHC heads and I don't think anything interchanges with a normal SBC. I feel like anybody with a LT5 would know what they have.

Speaking of the C4, the L98 350 in the regular C4s had aluminum heads on an iron block in the later years.

could it really be a rover engine?

The LT5 is a GM/Lotus/Mercruiser engine stuffed in a car and it doesn't look much like a SBC, even in shortblock form, even though it shares a lot of architecture.

The Rover looks nothing like a SBC.

That stupid HT4100 from Cadillac had an aluminum block and iron heads.

There are quite a few aftermarket blocks out there, perhaps he has one of those with a lot of selective memory.

GM used to sell aluminum 4" bore medium journal blocks over the counter, but never installed in anything. They still sell a 4.125" bore large journal block, but that would be a 400 block..

There have been a lot of aftermarket aluminum smallblock blocks sold over the years, too..

Rodeck and Donovan make them for racing applications. They are pretty common in PA.

Thanks for the hints, i'll check with him and come back. I'm waiting for pictures :)

wheels777 wrote: Rodeck and Donovan make them for racing applications. They are pretty common in PA.

How hard would it be to adapt one of those for street use?

There were aluminum and even some magnesium aftermarket blocks, in all sorts of different deck heights, with and without water jackets.

I knew I stumbled into something cool when I went into the back garage at work and saw an aluminum, tall-deck, no-jackets SBC block on a rollaround cart, bare except for studs. Head studs, mains studs, even timing cover studs.

They were never factory production options, but they were available in race guise. As far as I know, GM Europe manufactured some aluminum gen I blacks for military applications, as well.

Agreed... Chevy made an aluminum small block, but never put it in a production car. I had one once that I was going to build but it ended up having stress cracks in all the wrong places.

They were basically the same casting as the iron 400 version and didn't beef up areas that should have been beefed; main webs, deck, etc.

I think the aluminum version was siamesed, but only bored and sleeved to 4" instead of the 400-sized 4.125"

wheels777 wrote: Rodeck and Donovan make them for racing applications. They are pretty common in PA.

it's unfair to say "they are pretty common in PA" when you really mean "my barn is full of them and accounts for 95% of the aluminum 350 blocks in PA"

also 318 hemi? i want an old hemi bad.

patgizz wrote: also 318 hemi? i want an old hemi bad.

No such thing as a 318 Hemi. There was the Plymouth 318 Polysphere, which had vaguely Hemi-shaped combustion chambers. The old Hemi variants are the Chrysler Firepower 331/354/392, the Desoto Firedome 276/291/330/341/345 and the Dodge Red Ram 241/270/325

NickD wrote:

patgizz wrote: also 318 hemi? i want an old hemi bad.

No such thing as a 318 Hemi. There was the Plymouth 318 Polysphere, which had vaguely Hemi-shaped combustion chambers. The old Hemi variants are the Chrysler Firepower 331/354/392, the Desoto Firedome 276/291/330/341/345 and the Dodge Red Ram 241/270/325

Thats what i thought. I passed on a cheap 392 car a couple years ago and have been upset ever since

patgizz wrote:

NickD wrote:

patgizz wrote: also 318 hemi? i want an old hemi bad.

No such thing as a 318 Hemi. There was the Plymouth 318 Polysphere, which had vaguely Hemi-shaped combustion chambers. The old Hemi variants are the Chrysler Firepower 331/354/392, the Desoto Firedome 276/291/330/341/345 and the Dodge Red Ram 241/270/325

Thats what i thought. I passed on a cheap 392 car a couple years ago and have been upset ever since

There had better been a very good reason for that, like "was on the way to the hospital for emergency bowel resection surgery" or "car turned out to be haunted by the angry ghosts of the five teenagers who died in it in 1958".

More like "mmmmmmm392hemidrooooool". "I'm pregnant" "GAH"

Side note i might need your help on my $2017 car relatively soon.

also the LS engines and a few 5.3's had aluminum blocks. They started in '97 so they would be almost 20 years old by now, guess it depends on what 'old' means.

So, educated me on this. What's the advantages of an aluminum block other than weight? Are there performance advantages? Better cooling? More power?

-Rob

Weight.

You guys know there are hemi conversion heads for LA small blocks. Expensive, but you could make a true 318 hemi and troll supreme.

NickD wrote:

patgizz wrote: also 318 hemi? i want an old hemi bad.

No such thing as a 318 Hemi. There was the Plymouth 318 Polysphere, which had vaguely Hemi-shaped combustion chambers. The old Hemi variants are the Chrysler Firepower 331/354/392, the Desoto Firedome 276/291/330/341/345 and the Dodge Red Ram 241/270/325

Didn't the Aussies also get an I6 hemi?

Saw a ford 429 hemi once, back when I was lucky enough to get a tour of Smokey Yunick's shop, that was a sight to see. Was sitting next to a Chevy "mystery motor", which was the precursor to the 409. Was a good day.

But back on topic, there have been so many aftermarket and factory performance SBC blocks, I don't doubt it could be an aluminum one. But like the other guys said, wouldn't have been a factory installed piece.

In reply to HappyAndy:

It's more of a semi-hemi, like Ford's. The marketing department thought it would sell better with the name. Same reason they used the term Six Pack with the 3 Webbers. Bad ass motor, regardless.