The numbers should have been automatically corrected by the dyno's software to the "Motorsports Standard Atmosphere" (for those of you scoring at home that's 60 deg F, 29.92 in Hg, 0% rel. humidity)...the handful of dynos I've seen (and been on) spits out both corrected & uncorrected numbers, on the same printout. That way it's quasi-possible to compare numbers between dynos... --------------------------------------- Hillbilly Racing Team "Either you own the car, or the car owns you..."
That's very possible with the HUGE duration/lift ZL-1 or L-88 sticks...but with our more mundane L-72 cam I doubt the losses would be half that much... ---------------------------------- Hillbilly Racing Team "Either you own the car, or the car owns you..."
I think that's exactly the same situation at Olds. Both the W31 and the W30 cars have very large duration cams, but the W30 cars have much better exhaust manifolds (69-72 W/Z) than the 350 W31(all use same single exhaust manifolds with a cap on the crossover). That's why the W31's gain so much more hp with addition of headers and W30's don't gain as much. Headers and big cams also really pay off in the high rev area where the W31 thrives, and the W30 dares not travel. (>6500 RPM). Both packages were developed on the dynos with headers, so they benefit from them, just not as much on the big block as the small block. W31 was never intended to be a street driver car, so why waste time and $$$ developing a new set of exhaust manifolds for 500 cars a year. Different ballgame on the big blocks as the standard 442's benefitted big time from the improved manifold designs over the single exhaust variety on the 88/98's. Plenty of them around.
Casey, Casey, Casey, ....... Well, I got my Musclecar Enthusiast yesterday and checked out the subject article. I've gotta say, I'm really disappointed with Casey, misrepresenting the facts as he did -- just so he could lob a grenade over the wall and watch us scatter. He seems to be such a stand-up guy otherwise, but with this deceit we are left wondering what other little lies he might be hiding. :moonu: The two data points Casey presented are indeed true. But this is a perfect example of how looking at the two peak points on a torque and horsepower graph can really mislead. Any bozo (even me) upon observing the graphs published in the magazine can see the enormous difference in the two torque curves from all the way down at 3500 rpm (where they start) up to the 5000 rpm area. The header'ed engine will get you down the track way quicker. It's only above 5000 rpm where the benefits seem to disappear for this particular engine. Now, I may be a simpleton (after all, I do like headers), but my interpretation of this situation is that above 5000 rpm, the exhaust manifolds are no longer the "weakest link." At those speeds, the stock heads or perhaps the intake manifold are restricting flow more than the manifolds, so the headers don't help much up there.
Brian, I cannot believe that you just posted that. How dare you say that about me. You ready to go head-to-head with me on Oldsmobile performance, or you just gonna call me a liar and someone full of deceit on a public forum ? I'm ready pal ...... Got your gloves on ? .......
Me too Steve ...... :af: But with that one, I would have probably needed to throw my own-self off of V8Buick ....... :af:
It's all in fun, Manifold Boy, all in fun. Oh, and I'll be ready to rumble just as soon as I get my 455 with headers to run as quick as your 350 without. ou:
Maybe, Andy, but just opening things up doesn't always increase the flow and performance. Depends upon where it needs it and where you do it. Extrude honing may not help you on that. Seems to me there were some guys who used epoxy to add things in intakes (heads, too?) to improve and balance flow, can't remember which cars, but think they started with a B. Epoxy wouldn't last in an exhaust manifold, but there are things that could. So Brian, things are shaping up for a good grudge match with your headered big block and Casey's manifolded snmall block. The NSCA race in September at Stanton will run the new Factory Stock class. You can run your car in that class for three races before you have to comply with the manifold rules. Should be a good match between them. :Brow:
Don't bother bringing the bills, Casey. I'll just send you a check. Is Bozo your first or last name? :grin: You're running 9 mph faster than me. Apart from a hundred pounds of air conditioning and a hundred pounds of extra (big) block, what does that tell you? It tells me that the previous owner of my W-30 put in too much cam, didn't degree it, and used pistons that knocked the compression down below 9:1. There's not much sense in grudge matches until I get a chance to build the engine the way *I* want it. I've knocked well over a second off my ET and gained 5 mph in the years I've owned this car, but I can only polish a turd so much. Don't worry -- I'm a procrastinator, so your wallet is safe for a few years. I figure I'll rebuild the engine by the time I'm 80. And by then I'll be one of those old farts that wants to use manifolds instead of headers. :blast:
Jeez -- that's unfortunate Brian. You make everything out to be rose-colored-glass-windows with headers, and then you back-peddle ....... When the dime hits the asphalt, you make things sound like you weren't part of it. I can only guess that if headers were on the "up-side", you'd be screamin' from the roof tops ....... If I were you, I'd send the motor to a NON-Electrical engineer ..... it may help ....... :TU:
Come on Brian, Bozo calls you out and start making excuses? :spank: I would love the opportunity to see how you and I would do duking it out. You have a/c, I have a/c: you have a big block, I have a big block: you probably have 3.23 gears, I have 3.23 gears: you have 14" tires, I have 15" tires: you have headers, I have manifolds. On paper, the advatage would go to you with the slightly smaller tire (better use of the gear ratio) and the lighter weight of the headers. I don't know if you were around on Saturday, but the carb tuning that Jeff Sawruk did help to net the fastest time my car has ever run. Just pull the motor out, look things over, and when you go to drop the motor back in, replace the headers with manifolds. It is that easy!
