I have been doubfounded about the fact that the old (67-69) camaros had alot more HP that the newer cars do. And why do people have to spend thousand of dollars to even match the stock HP of the older cars. What are we missing and why does it seem imposible to get that kind HP. What do we have to do to get the HP of the older cars (minus nitros and superchargers)?

 

Put the crack pipe down. Remember, older cars were rated at gross horsepower, not net horsepower. This accounted for a good 20-25% difference. A stock 285hp LT1 Z28 spanks the "350 horse" LT-1 camaros of the late 60s-early 70s by about a full second in the quarter mile. And that is even with the older cars getting 3.73s and headers. Not to mention the 12.89 that GMHTP got out of a stock LS1 camaro. The big block 396 Camaro couldn't even run that fast. I'm not sure where your getting your info from. But if it's from an overweight, balding NASCAR fan reliving the 60's, it's time to get your facts from someone else.

 

I have one word for you: emissions.
Plus don't forget the fact that the numbers of the older cars were calculated differently, for example a 425hp engine measured in '67 would be about a ~380hp (maybe even less) engine with today's standards.

 

Well I am a hugh NASCAR fan and even a fan of the veterans.. But that aside. I have never heard the diff of gross and net HP. This is just what I have heard and then seeing the docum. on the old american muscle cars they spoke of 400 HP and that is why I am asking. So are you saying that a stock 95 z would beat a stock 69 z? I am trying to learning here and respond to the old balding NASCAR fans who said never buy a newer muscle car!

 

SAE changed from Gross Hp to Net Hp in 1972.

With Gross Hp, measurement was taken at the flywheel, without any accesories (alt, PS, AC whatever), and probably had an open exhaust, and maybe even a jetted out carb. Usually a blueprinted engine. There were some exceptions to this (426 Hemi comes to mind, it was rated at 425Hp, in every configutation, including 4bbl and dual quad)


With Net Hp, measurement was taken at flywheel, but with all accesories and equipment installed and operated. This included a full exhaust system, stock jetting (or F.I. map). Basically, wht the customer would actually get.

As for the current 350's (LT1, LS1), you need to remeber that their torque curves are much more usefull than the older 350's.

The High Hp 350's were very peaky engines, with very little to offer at low to mid rpm.

 

As far as I know, older (Higher HP) cars had more inefficent drivetrains and suspension resulting in less power to the ground, not to mension they were also heavier.

 

theres actually a few factors that contribute to this...

As said above, the gross HP vs SAE net HP ratings account for the biggest differences...but some of it was revolving around the technology of the time. Its pretty widely accepted that many of the motors put out back then were underrated (the 426 Hemi has been dynoed eclipsing 500HP), and they could get that much power due to the higher octane leaded gasolines available which allowed higher compression ratios. We get a similar compression ratio out of our LT1's using cooling technology (reverse flow, etc) and that allows our engines that are 100 cobic inches less to achieve good numbers compared to the small blocks of the time...imagine if we applied this to a modern big block which we can't do because of increasing federal standards (emissions, Corporate Average Fuel Economy, etc)!

The power was definitely there in the BEST of the old musclecars (the ones you hear about all the time) but the tire technology was so poor many couldn't get themselves out of the 13's to save their lives. Strap some modern rubber on them and they run a lot better (Some of the old Buick GS stage 1's are running mid 12's with some headers and good tires). One thing to keep in mind though, the cars you hear about are the best of the best, and not indicitave of overall performance for that particular brand at all...the corporate average HP numbers have drastically increased during the 90's and up.

So for comparisons sake, lets take the best of the best just like they did...so we are talking about comparing the 426 Hemi 'Cuda or Charger against the Viper...the viper could have any of those cars for lunch any day. Chevy would have to compare the Z06 to the old LS6 Chevelles, and again it would smoke it hard. Ford would pit the old Boss 426 or 428 SCJ against the 2003 Cobra, and I think the Cobra would take the day again. How about the Shelby Cobra? Its going against the Saleen S7, and I don't think we need to think hard to pick the winner there.

Its all in how you look at it.

 

okay all that being said the stock z28 rated at (275/285) is still quite lower than 350 or 360 that the older engines produce. To summerize what has all ready been said basically the older cars have higher HP but can't performa as good as the newer ones do? I would like bothe how do I get there.

 

While I agree that newer cars are usually faster, you must br fair.

The tires back then sucked, I have seen many classics run almost a second quicker than the times published in the old magazines with modern tires. Also SOME of the engines back then were under-rated similer to how the LS1 was. The only one I have proof on is the 426 Hemi but I have heard about others being under-rated.

BTW: Check this out,

YEAR/MODEL ET/MPH ENGINE ADVERTISED HP TRANS GEAR
1966 427 Cobra 12.20@118 427 CID 425 four-speed 3.54
1969 Road Runner 12.91@111.8 440 Six Pack 390 four-speed 4.10
1970 Hemi Cuda 13.10@107.12 426 Hemi 425 four-speed 3.54
1970 Chevelle SS454 13.12@107.01 454 LS6 450 four-speed 3.55
1969 Camaro 13.16@110.21 427 ZL1 430 four-speed 4.10
1968 Corvette 13.30@108 427 435 four-speed 3.70
1970 Road Runner 13.34@107.5 426 Hemi 425 automatic 4.10
1970 Buick GS Stage I 13.38@105.5 455 Stage I 360 automatic 3.64
1969 Charger 500 13.48@109 426 Hemi 425 four-speed 4.10
1973 Trans Am 13.54@104.29 455 SD 310 automatic 3.42
1969 Corvette 13.56@111.1 427 L88 430 automatic 3.36
1969 Super Bee 13.56@105.6 440 Six Pack 390 automatic 4.10
1969 Boss 429 Mustang 13.60@106 Boss 429 375 four-speed 3.91
1970 Challenger R/T 13.62@104.3 440 Six Pack 390 automatic 3.23
1970 Torino Cobra 13.63@105.9 429 SCJ 370 automatic 3.91
1964 Polara 500 13.70@107.37 426 365 four-speed 3.23
1969 GTX 13.70@102.8 440 375 automatic 4.10
1969 Dart 440 13.71@105 440 375 automatic 3.55
1971 Road Runner 13.71@101.2 440 Six Pack 390 automatic 4.10
1971 Cuda 13.72@106 440 Six pack 390 automatic 4.10
1971 Corvette 13.72@102.04 454 LS6 450 four-speed 3.36
1971 Super Bee 13.73@104 426 Hemi 425 automatic 4.10
1968 Hurst/Olds 13.77@103.91 455 W-30 390 automatic 3.91
1968 Firebird 13.79@106 400 HO 335 four-speed N/A
1967 Corvette 13.80@108 427 435 four-speed 3.55
1971 Boss 351 Mustang 13.80@104 Boss 351 330 four-speed 3.91
1966 Satellite 13.81@104 426 Hemi 425 four-speed 3.54
1969 Coronet R/T 13.83@102.27 440 375 four-speed 4.10
1968 Cyclone GT 13.86@101.69 428 CJ 335 automatic 4.11
1969 Nova SS 396 13.87@105.1 396 375 automatic 3.55
1969 Shelby GT-500 13.87@104.52 428 CJ 335 four-speed 3.91
1970 Olds 4-4-2 W-30 13.88@95.84 455 W-30 370 automatic 3.42
1962 Corvette 13.89@105.14 327 FI 360 four-speed 4.10
1969 Barracuda 13.89@103.21 440 375 automatic 4.10
1969 Mustang Mach I 13.90@103.32 428 CJ 335 automatic 3.50
1967 GTO 13.90@102.8 400 RA 360 automatic 4.33
1970 Trans Am 13.90@102 400 RA 345 four-speed 3.91

Some of those cars aren't to slow.

 

The people who say "never buy a new muscle car" are the reason there are no new (American) muscle cars!

"The new GTO ain't a GTO cuz' it ain't got no hood scoop on it, tell you what. That makes the car 1/2 second faster in the quarter mile"

"Dern tootin"

"I remember Sally and Jim-bob and Mary and me used to take that Goat up to Crabman's creek for some neckin'! That car ran the quarter in 12 seconds, I timed it on my Timex watch, I sure did"

"Hell yeah"

"Well, I best get back before the missus steals my Pabst Blue Ribbon. Gonna take the old hag down to Greason's for dinner."

Quarter miles should be run on a twisty road, anyway.

 

A couple things older cars didnt have to worry about:

No emissions/sound/smoothness restrictions

Unleaded gas


The older musclecars were also constantly in need of carb, valve and other tuning adjustments to run well. Todays cars are 100xs more reliable.

 

i know there was a post on this somewhere here...
search and you could find it

but basically, old cars had just an engine sitting on a dyno and that was what measured hp, before it was in the car
now cars are tested with all the emissions, accessories, etc. all of which strangle hp

so in comparison
(it went something like this)
a 350 hp z28 had like 275 or somewhere close to that compared today's models (converted from gross to net)
a 350 horse ls1 (vette ratings) would be like 450 horses or something like that
if i find the thread about this, i'll post it
it's got a breakdown of a lot of old musclecars converted to net, and a lot of new muscle cars converted to gross, just to give you an idea of it

o, and take in account that technology has advanced to give us...better tires, trannies, rest of the drivetrain, etc. and htat also helps the new musclecars spank the old ones
and yes, whoever posted, an ls1 z28 would absolutely take a 69 z28

 

here we go...
search for "gross net horsepower" in all forums, in the entire thread, and you will find plenty of topics discussing it, too many for me to post links to now

 

Before Emissions at the Muscle Car peak those auro Engrs. did anything and everything they could to get more power. They had barely streetable cams, huge cubic inches, huge 4-barrels, some had 2-4 barrels.

Could you imagine the power we would have from the factory today if they had no emission rules to follow, if we had much higher octane gasoline. The technology today ie. Fuel Injection, Programable fuel/spark maps, even the camshafts we have today were not possible to make in the old days.

But even if the factory could make these higher performing cars today, we would still find something to improve upon, thats what we do.

 

My boss has a mint 66' Plymouth Fury...440 BB....like 345 meats in the back, (aftermarket 15" rims) only like 35k original miles when he ran it at the track at sea level (he got it off an old lady who barely used to buy groceries etc etc)

He ran 14.8 once, the rest were 15.0s....to me, a 440BB rated @ 390HP running 15s on huge meaty rear tires isn't too impressive. Now, the thing does have a 2.90 rear....I'm sure some 4.xx gears and a stall converter would drop a full second, but still....I'd take a modern EFI setup any day.