Posted by CoopertownBob on January 11, 2014 at 20:48:55 from (67.172.102.201):
In Reply to: HP vs Cu. In. posted by Mike (WA) on January 06, 2014 at 14:04:46:
Right. I believe, if memory doesn't fail me, that Chevy's 450 HP rated 454 in 1970 ended up all the way down to like 245 when they changed to SAE as installed standards, by like 1973 or so. Of course, this was also the beginning of the Federal mandated emissions, which led to big changes in tuning specs to meet those standards.
Something that always strikes me as funny is, I used to hear guys talking about changing out the heads, cam, adding headers, different carb, and so forth, just looking for 50 or so HP. With some of those old all motor cars, you could get that much just by changing the mufflers!
Another really big thing that has contributed to the higher HP 'installed' ratings is the much closer tolerances they can put today's engines together to. In the late 60's, a Z-28 Camaro was factory rated at 290 HP, which was obviously intentionally low, but if you balanced and blueprinted the engine, they made more like 500 HP. Back in the day, the NHRA re-rated them several times to account for this fact, trying to keep other cars that 'on paper' should have been equal, competitive with them. I don't think you could realize that same kind of gain with today's engines from doing that, simply because they are put together so much closer to 'blueprint' from the factory.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Engine Valves - Some Helpful Information - by Staff. Intake - On the intake stroke the piston moves doward, sucking in carburized fuel through the open intake valve. Exhaust valve is closed. Compression - With both the intake and exhaust valves closed, the pistons upward stroke compresses or squeezes the fuel into the combustion chamber. Firing - Ignited by the spark, the compressed fuel explodes and forces the piston downward on its power stroke. Intake and exhaust valves are closed. Exhaust valves and seats are exp
... [Read Article]
Latest Ad:
Oliver 550 Diesel runs like a watch three point hitch pto engine gone threw about two hundred hours ago nice clean tractor
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.