I have been to several Olds sites that indicate that A (one I bought) 1967 Cutlass Supreme Convertible has 320 stock HP. Someone else (not olds site) said it was 230 HP. While it doesn't matter a whole lot to me,It would be nice to know

Thanks!

 

Your Supreme could have a 330 ranging from 300-320 hp. They did not make a 230 hp 330. "Someone else" is either ignorant, jealous, or both.

You can find this information yourself in the "SPECS" booklets on Wild About Cars.
http://wildaboutcarsonline.com/cgi-b...aldisplayed=21

Wild About Cars. http://wildaboutcars.com. An information supersource, especially Oldsmobile. More Olds content than anywhere else on the internet and continuing to grow.
You'll find Chassis Service Manuals, Product Information Manuals (AKA Assembly Manuals), Inspector's Manuals, and other documents that will contain this and much much more.
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Could be the difference between Gross and Net HP coming into play here.

 

Three 330 cubic inch Olds engines were made in 1967:
9:1 compression 2-barrel engine, 250HP
10.25:1 compression 2-barrel engine, 260HP
10.25:1 compression 4-barrel engine, 320HP

I have to think the 10.25:1, 2-barrel engine HP is very underrated at only 10HP more than the 9:1 engine.

 

Umm..........I know that you know, but you forgot the L73. (9:1, 4-bbl, 310 HP) And you can question the 10 HP difference there too!

 

So from 2-4 bbl adds 60 H.P. That's impressive.
So if I added dual exhaust instead of original single,how much more performance would it add I wonder?

 

H.P. differences can be due to aforementioned carb and exhaust options, sure, but don't forget more dished vs more flat-topped pistons and camshaft specs. Putting a 4 bbl carb or dual exhaust on a low compression motor probably won't do much for you.

 

Hey Alien But this is a high compression engine.And I'm not sure if the pistons are flat or dished.Would be interesting to know.I have read however that higher compression engines burn hotter octane gas better than lower. resulting in less ping and better performance.But I am still learning.New testing methods back timing off to accomodate lower octane I think.
I was wondering as a general reference if adding dual exhaust adds more h.p.
I just learned the difference between Gross and Net H.P. So there's where I'm at!
It's fascinating to me.As I was once the ignorant one thinking that the mid 60 engines were "way better" on H.P. The over inflation of h.p and the underrating h.p due to racing and insurance in the 60's is interesting to read about.http://ateupwithmotor.com/automotive...orsepower.html Thanks

 

The 310HP 330 engine was a 1966 Cutlass engine.
It had a 10.25:1 compression ratio with a 4-barrel.
It is described in the '66 dealer's brochure as
"Optional at no extra cost on Cutlass. Extra on F-85 & Vista Cruiser."

It was not available in '67, at least it was not listed in the dealer brochure as an option.

 

Yes it was a '66 engine too, but was carried into '67 as were most of the '66 engines.
Could have been an error in that brochure, or maybe the original plan was to drop it (most brochures are printed very early), but it was there for '67.

Attached is from the SPECs book and the Product Information Manual.
And for others that are playing along at home, these are available free of charge at Wild About Cars.
Wild About Cars. http://wildaboutcars.com. An information supersource, especially Oldsmobile. More Olds content than anywhere else on the internet and continuing to grow.
You'll find Chassis Service Manuals, Product Information Manuals (AKA Assembly Manuals), Inspector's Manuals, and other documents that will contain this and much much more.
Dealer Brochures, magazine ads and articles, and a home page for you online with your own garage where you can show off what you have.
Free to join, free to learn.

 

I hate to be a stickler for grammatical error. But the horsepower is already there! All you're doing is allowing your engine to breathe easier and harness the horsepower it already has. Not "adding" horsepower.

I havn't read the rest of the thread, but i upgraded my 72 350 block to a 4bbl carburetor and boy does she fly on the road.

that is all, best of luck with your build.

Tony

 

Okay lets be a stickler. He didn't say added horsepower, he said added performance. And even if he did say horsepower, that would still be correct. The horsepower is not "already there". What is already there is only the "horsepower potential". Adding dual exhaust will indeed "add horsepower" as will adding headers. Horsepower is a measure, not a set-up.

 

Until I checked the brochures, I always thought the 310HP engine existed in '67.
What you mentioned about it being a carry over to early '67 is probably what happened.

I never actually knew the difference between the 310 and 320HP.
I've heard different things like the 310 was single exhaust and the 320 was dual.
Does anyone know exactly what the difference is?

 

I didn't mean to imply that it was a carry over to *early* '67. It was available all year. The difference should be pistons and cams.
Dual exhaust was optional on both.

 

To further clarify, the 310 hp was low compression and burned regular gas, as opposed to the high compression 320 hp version that burned premium.

And that 320 hp version was no slouch, either. It was a pretty impressive high revving small block.

 

Seeing that I have the 10:25:1 (Think that's what it is, W-G stamp)
Wouldn't reason suggest that I burn 93 octane for smoother performance?
Also there was a NO LEAD additive in the trunk.I guess I should be using it?
They say that no question is a dumb question.So why am I feeling so dumb right now?
Thanks