ahh reciprocating mass.... that sounds you could be onto something. It also seems that for aliminum blocks they use at least 4 bolt if not 6 bolt mains.
Could you intepret that alloy blocks have a greater tendancy to flex when you have large reciprocating mass??

That as the revs increase the amount of time between successive applications of said mass against the main bearings decreases, and thus reduces time available for the bearings to de-stress, resulting in greater chance of failure?

whew got that all out....

And the wikipedia entry doesent say much, just that its stronger, which we all know.

Quote:
Sorry, but the Model D of 1917/'18 was a V8. Cadillac got the V8 in 1914 & it was a flathead.
I was checking out a Model D just the other week. Impressive & big.

The first production automotive OHV V8 was the Scrips Booth in 1915.
None of these used a 4 bolt main cap.

Back then my papa was still driving his (by then used) 1904 Mercedes Twin-Cam four-cylinder.

There's nothing new is there? Except maybe 4-bolt mains.

dd

are you having a dig at me and my persistance....

Quote:Even that is relative since the 426 Hemi had cross bolt caps in 1964. That's 43 years ago.

You're right of course about those things we think of as being new technology actually being old.
The 1914 Duesenburg indy car [an American make] had OHC with 'walking beam' valve operation, same as our L series engines.
Their 1922 passenger model was SOHC with 3 valves per cyl & by 1929 they came standard as DOHC with a 4 valve layout.
Supercharging was optional.

The only thing truly new is solid state electronics as even in 1958 you could buy a new Chrysler, DeSoto, or Dodge performance model with Bendix EFI, but it wasn't solid state electronics, which is what killed it in the end.

Oh, & I suspect that your papa was driving a 'Benz' as the Mercedes name didn't come along till later.

I am interested in the reference to A Series engines being used in Formula Pacific & Formula 3 cars. The engines have a long history in clubmans / sports 1300's but I wasn't aware of their use in international formulae (you learn something everyday). From memory the Pacifics used 1600 twin cams with specific motorsport heritage eg Cosworth, so that must have been some impressive 1300cc A Series!

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But the D series was 2 halves bolted together.
So how many years ago does it make it that Chevy had crossbolts?
Did it even use main caps champ?
Is there any photos Im sure you would have taken?

I'm not sure about the blocks/bearing journals flexing, but Aluminium block do experience bore distortion under boost when supercharged. Not really relevent to this thread, but my analogy did use one of those motors as an example.

Any news on photos?

Bump.
Still interested in seeing photos of the said engine.