Actual Horsepower Of '60s/'70s Muscle Cars

[hightower99]

Modern ECUs ARE runnign with "constantly retarded timing" --- because they advance the timing to match the throttle position and load on the engine to maximise the burn. They do this by using a knock sensor. SO it runs lean and time the spark as close to the limit and when it knocks they back off.

That just doesn't make sense... You say they are constantly running retarded timing (retarded being defined as later then the base point) yet you agree that the systems are constantly trying to advance the timing until the engine starts knocking then they back off abit and try to advance timing again. Doesn't that mean that modern engines tend to run with advanced timing most of the time?

"Pulling timing" -- do you mean setting the timing up PROPERLY ?
ie NOT running it too close to the limit as it has no feedback control ??
or what ????

No of course not. I mean without overly retarding the timing. Technically you could retard timing on any given engine enough to run almost any octane fuel without knocking but that isn't the point. The point is to run well without knocking.

"fail to run" -- by YOUR definition ?
Other than exotic small capacity and VERY exotic larger capacity I've never come across an engine that couldnt' be set to run on todays fuel. TO get best PERFORMANCE though they were designed to use higher octane. I struggle to see why you are so confused over the relationship

by today's fuel do you mean today's regular? Premium? superpremium? UltraSuperAviationPremium?

By your definition again.
I can list quite a few.
WHere are you getting these "facts" from ?
Theory or practical application of theory ???

Ok hopefully we all know what Octane numbers mean and why they are important... Just a quick brush-up:

Octane rating of a fuel is a rating of its resistence to autoignition. Basically Iso-octane (specifically 2,2,4-trimethylpentane) is given the value of 100 and n-heptane is given the value of 0. Now a fuel's octane rating means it exibits the same autoignition resistence as a mixture of iso-octane and n-heptane. For example 95 octane fuel shows the same resistence to autoignition as a mixture of 95% (by volume) iso-octane and 5% (by volume) n-heptane. Values over 100 are possible because iso-octane is not the most resistant to autoignition. Also rated fuels do not neccessarily contain any iso-octane or n-heptane.

Now the autoignition point is directly effected by the temperature inside the cylinder which is roughly derived from the formula T2 = T1*Cr^((k-1)/k) Where T1 is the initial temperature (roughly intake temperature) Cr is compresion ratio which can be either static or dynamic depending on how accurate you want to be and "k" is the ratio of specific heats of the working fluid (theoretically 1.4 for air but a more realistic value is 1.2 or 1.3). Once you know the temperature you can find the minimum octane required. If an engine needs a higher octane then this number then it is most likely because hot spots and or lean spots are being created in the combustion chamber.

since the lower compression engines of the '60s run okay on today's fuel, do they have better combustion chambers than the high-compression engines?

Actually I did answer that question. Yes there combustion chamber design is close to the same.

[Matra et Alpine]

ht, sadly you are using perect-world math to "prove" a 60s combustion chamber is "bad"
Recommend you research real world examples more and get a grasp fo the WHOLE picture, not just the little bits of theory.

[hightower99]

ht, sadly you are using perect-world math to "prove" a 60s combustion chamber is "bad"
Recommend you research real world examples more and get a grasp fo the WHOLE picture, not just the little bits of theory.

Actually it isn't really perfect wolrd, but it isn't really real world either... I like to call it Rough Estimate world

Also I am not proving that it is bad I am trying to point out that it is highly likely that some part of the design is contributing to the fact that these engines need to run on higher octane gas then is technically neccessary for the other known design variables.

My basic point is that if any given engine needs to run on higher octane gas then the design variables require then there is most probably something to improve.

[-What-]

hightower...you should spend more time studying, and less time teaching. You rarely know exactly what you're talking about.

[hightower99]

hightower...you should spend more time studying, and less time teaching. You rarely know exactly what you're talking about.

And you would be an expert at both studying and teaching of such a caliber that you can make such a comment without it being completely meaningless?!?

I think not...

[-What-]

And you would be an expert at both studying and teaching of such a caliber that you can make such a comment without it being completely meaningless?!?

I think not...

At the end of the day, you probably wish you could be me.

[henk4]

At the end of the day, you probably wish you could be me.

can we receive your wise observations regarding the topic at hand? IMHO Your contribution so far has not justified personal judging of other participants in this discussion....

[-What-]

can we receive your wise observations regarding the topic at hand? IMHO Your contribution so far has not justified personal judging of other participants in this discussion....

Please. Like it matters what I say. I could post the blue-print to a cancer cure on these forums and you all will "flame" it just because of who I am. Unfortunate for your minds, I'll reserve my input for myself.


The real question of the day is: Who are you?
Best answer: You're not me.

[hightower99]

The real question of the day is: Who are you?
Best answer: You're not me.

And there is no knowledge that warms me so...!

[henk4]

Please. Like it matters what I say. I could post the blue-print to a cancer cure on these forums and you all will "flame" it just because of who I am. Unfortunate for your minds, I'll reserve my input for myself.


The real question of the day is: Who are you?
Best answer: You're not me.

I would never think that you are able to exceed the stupidity levels of your previous posts bust you always manage to achieve that....

[Equinox]

Ouch... the flaming that goes on here. What would all your mothers say if they seen what goes on here!

Back to topic.... ummmm. I seem to have forgotten what the topic was!

quote by -What-

Best answer: You're not me.

I think I can live with that... as painfull as it is!

[wannabeatorino]

did the book go into the earlier years??? we have a 1954 331 hemi according to the factory specs it was rated at 180 hp what do you think?

[Fleet 500]

did the book go into the earlier years??? we have a 1954 331 hemi according to the factory specs it was rated at 180 hp what do you think?

Yes and no.
I've read that the first rating for the 331 Hemi was 180 hp, but it was purposely mildly tuned and rated at that figure so it would be easy to up the rating to keep ahead of the Cadillac V-8. (In 1951, the Cadillac V-8, also 331-cu-in, had a 160 hp rating; the Chrysler 331-Hemi, 180 hp.)

So, in later years, all the engineers had to do was raise the compression and/or change the cam to get more hp.

[harddrivin1le]

Anyone who thinks the 60s "musclecar" engines made a lot of power by today's standards is on drugs.

Here is a dyno test of a ZL-1 427 Chevy. "Back in the day," that was THE horsepower king. It required 103 octane fuel and Chevy built just 69 of them. The engine option alone cost more than the rest of the car(!)

CRG Research Report - COPO 427

Gee, it made a whole 376 SAE NET HP. BFD. A 2001 Z06 Corvette made 385 SAE NET HP from just 346 cubic inches (plus with cat converters, AC and lots of other options).

Here's a topic on the old "Gross HP" numbers and what a crock they were. It was written by the editor in chief of CAR AND DRIVER, who has a degree in mechanical engineering from MIT and worked as a engine designer for Ford:



Here's a freshly built 1970 Buick Stage 1. It's as close to stock as possible, but had an overbore (unshrouds the valves for more power in addition to adding displacement). The best it could do was 381 HP and that's with NO MUFFLER, NO AIR CLEANER, MINIMAL ENGINE ACCESSORIES and with figures that were "corrected" to the more generous SAE Gross atmospheric standards:



Here's a vintage 1966 GTO chassis dyno test. "335 HP" Gross and all it could manage was 180 HP at the rear wheels. Any modern 6 cylinder Nissan Altima would put that to shame.



Here's a vintage, low mileage 426 Street Hemi - "the legend!" 315 Rear Wheel HP on a chassis dyno. Yawn. My 1999 LS1 Camaro made more than that when it nothing other than a cat-back exhaust bolted on it.

Hemi Vs. Viper!

Here's how they ran when they were STOCK and NEW, but fitted with NINE INCH WIDE DRAG SLICKS (thereby eliminating the "skinny tire" excuse). Not surprisingly, that's just about what one would expect from a ~ 3,800 pound car that's putting 315 HP to the wheels (which means ~ 365 HP at the crank):



Oh, and here's one for the Ford fans. It contains the results of EIGHT vintage Mustang chassis dyno tests. The 428 Cobra Jet farted it's way to a whole 240 HP a the wheels. My bone stock, 3.5 liter V6 Acura TL Type S will put down more!

8 Mustang Dynojet Showdown - 1967 Shelby GT500 - Mustang & Fords Magazine

I will tell you under no uncertain terms that I am a legitimate expert on this topic and have been published in several national magazines. The old cylinder heads and combustion chambers were JUNK by modern standards. The cams back then were generally lousy as well and most of them weren't really "hot" grinds to begin with. The ACTUAL compression ratios from that era were GROSSLY over-stated. Few topped 10:1 and the absolute greatest ACTUAL mechanical compression ratio was 10.6:1 (ZL1 and L-88 427 Chevy, both of which required 103 octane racing fuel and came with a tag on the center console stating that).

BY THE WAY: Even the octane ratings from that era were BS. They used ONLY the Research Octane Number. Today's Octane ratings use the RON + MON/2 method (MON is Motor Octane Number). RON is always higher. What was "102 octane" in 1969 would be rated at 97 octane or so today. Those old engines NEEDED higher octane fuel, since the heads used horrible valve angles, the chambers had lots of hot spots and swirl, tumble, etc. were just beginning to be understood.

Today's software design packages have resulted in advancements that couldn't be dreamed of in the 1960s.

[jediali]

welcome harddrivin1le, thanks for that interesting read.