ZR-1 Net Registry Forums - Point/Counterpoint: DOHC v OHV

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Re: Point/Counterpoint: DOHC v OHV

Wasn't there both a 396 BB and a 396 SB as well?

Re: Point/Counterpoint: DOHC v OHV

402 Big Block
400 Small Block (not to be confused with the Pontiac 400)

Re: Point/Counterpoint: DOHC v OHV

Quote:

Originally Posted by XfireZ51 (Post 230836)

396 was a big block back in the day, so displacement was not the determination for the designation. BB cylinder heads would not work on a small block and vice versa.

Well they actually had a 366 big block chevy for delivery trucks but i think it was designed w a small piston so as to have a thick cylinder bore as they expected extended periods of full throttle operation.

But in my opinion 396 is the same as 400 cubic inches especially since i qualified my statement with the word 'about' haha... The 402 BB was a 396 with a taller deck height for trucks as i seem to recall.

The conversation wouldnt be complete if we didnt talk about the BBC canted valve angles and better rocker ratios, but like the LT5, weight and packaging were a big part of its demise.

Re: Point/Counterpoint: DOHC v OHV

Isnt engine size and handgun caliber sayings similar? Your choice should start with a '4'.

Re: Point/Counterpoint: DOHC v OHV

I love all the turns this discussion has taken. We have like 5 sub discussions going...lol.

Quote:

Originally Posted by Bearly Flying (Post 230745)

Compared to say the F12s v12. Oem form.. 730hp from 6.2L. 505 from 7L. That's a 225 hp difference. The Ferrari v12 is Complex, expensive and spins to the moon....

Not sure if this is a criticism or defense of the chevy. The chevy motor can be driven like a pickup truck. That Ferrari isn't going to like chugging around at 1500 RPMs. So the DOHC nature of the F12 doesn't magically give it a decent bottom end. Driving on public roads, you're not going to spend a ton of time at 8000 RPMs.

If you look at the engine builders challenges and some of the protouring builds out there, there are plenty of nice idling street friendly 700+ HP pushrod engines.

How many Ferrari's do you see with 100,000 miles on them?

I don't go around looking at Ferrari odometers on a regular basis, but just due to the shear number produced versus the ZR1, I'm sure there are more out there than ZR1s in the same time span by a fair number. Look how many sub 50k mileage ZR1s are out there. I bet even if you looked at the percentages the Ferraris probably are higher mileage.

How many Ferrari's have set an International Speed Record?

Lots. They've set many more records than the ZR1. Just not the particular record you're talking about.

How many Ferrari's change their own oil or work on their engines?

Completely irrelevant to any of the numerous conversations at hand, but I doubt most of the people who plunked down the asking price for the ZR1s when they came out were doing their own wrenching either.

How many Ferrari's are even around from the early 90's?

As far as a percentage of those produced; probably more than ZR1s from the same period. Ferraris were just less likely to be parted out and more likely to be repaired, or stored in someone's shed. They don't usually end up in salvage yards.

Nuff said.

Re: Point/Counterpoint: DOHC v OHV

Quote:

Originally Posted by spork2367 (Post 230874)

I love the all the turns this discussion has taken. We have like 5 sub discussions going...lol.

It was meant to be a bit of a catchcan :-D for the way other threads "evolve" or "devolve" depending on your point of view.

Re: Point/Counterpoint: DOHC v OHV

Quote:

Originally Posted by Fully Vetted (Post 230730)

Which is why I think the 2013 60th Ann. 427 car will be highly collectable. Most likely the last BB Corvette ever produced.

And I wouldn't trust either one of them to get me to the grocery store and back let alone go on a road trip. But I guess that's beside the point...

I would trust that 959 in a heartbeat. Porsche's are the only true exotic that can be driven daily. 959 was the pinnacle of engineering back in that era. It was only surpassed by the 996 Turbo in performance, and even then the 996 was not as technologically advanced.

Quote:

Originally Posted by XfireZ51 (Post 230788)

Although it's a 427, that doesn't make it a big block. It's still an LSx block just a bigger bore. I may be oversimplifying it.

True big blocks are designed differently. They have a lot of cylinder material. The LS7 engine has almost paper thin cylinder walls. There is no service life in that engine.

Re: Point/Counterpoint: DOHC v OHV

Quote:

Originally Posted by Billy Mild (Post 230931)

True big blocks are designed differently. They have a lot of cylinder material. The LS7 engine has almost paper thin cylinder walls. There is no service life in that engine.

Chevrolet big blocks are an engine family made production from 1958-1972 I believe. Ranging from 348-454 ci then a later year over the counter up to 572 inches.

The LS7's (part of the small block engine family Gen. III & IV) are modern day monsters that are clean from a emissions view and get decent fuel mileage . The cylinder walls are very easily replaced. The service life of an LS engine is an extremely long one.

:cheers:

Re: Point/Counterpoint: DOHC v OHV

Quote:

Originally Posted by Billy Mild (Post 230931)

Don't break his heart and tell him that the 959 was using nikasil plated alloy liners, sodium filled exhaust valves, and a dry sump years before any Corvette...

Quote:

Originally Posted by FU (Post 230932)

Chevrolet big blocks are an engine family made production from 1958-1972 I believe. Ranging from 348-454 then a later year over the counter up to 572 inches.

The LS7's (from the LS engine family) are modern day monsters that are clean from a emissions view and get decent fuel mileage . The cylinder walls are very easily replaced. The service life of an LS engine is a extremely long one.

Big blocks were produced way later than 1972. I had a 2000 Chevy 3500 pickup with a 7.4. My dad still owns his 1997 Chevy Express 3500 van with a 7.4.

Re: Point/Counterpoint: DOHC v OHV

Chevrolet BB's were produced until 2007 as Vortec L18 truck engines.

Mark IV which were the performance engines stopped production in Tonnawanda NY in 72.