Yes my car drives similar to a smaller head car. I've had now 6 different motors different CIs with various heads cams, gears and convertors in this car. Come hop in it. we can blinfold you and ride in both TAs and see which you think is sluggish.Cliff has said his car has the same street manners. It's not just the head cc that impacts it! The higher end WOT is what everyone else says the big heads are only good for.How many guys does it take to say they are still using the same rpm range-not higher and they feel no change in low end "streetable manners"? It isn't just one or two guys.
How do you describe "street manners"?? 1000-2000rpm goose. 20-40 mph part throttle acceleration how much part throttle?Idle quality-at what rpm, running power brakes, A/C?My BIGGER RAIV iron heads on a 400 with a 304/312 hydraulic ran power brakes and A/C, was that streetable? Needed more gear than a 455 so apples to oranges. Did my 409 with a huge cam and an aluminum flywheel have a good bottom end-nope not until 2500 when it turned on.
410 ft lbs at 2000 is 410 ft lbs regardless of big heads or not, the flywheel doesn't know which it is. Can street tires tell 30 ftlbs when they are already broken loose? Yes maybe if we are towing a boat and need that greater low end from a dead stop idle to 2500, but guess how GM does that in their trucks- bigger motor with bigger heads! And how big are GM 454 heads?? The smallest oval ports are 280-290 cc for their truck torque motors!What were they thinking? Most of us aren't building truck pull motors-but even those are usually blown and on different fuel! We drive cars that go from idle to 5500-6000, and I'll bet little time is spent at 1200rpm.
The high end guys are seeing all the different variables besides ccs and using wet flow benches. They are seeing same size ports same dry flow cfm showing totally different wet flow patterns. And what we are ASSUMING with the theoretical better velocity on a smaller port is better air AND fuel filling cylinders. Yet chambers, port shape, port surface,swirl, tumble, boundry layers all affect that even on similar heads. That's why they use the wet flow to optimize the whole package.
Ponjohn you are right there are still variables, looking at average torque as well as peak or numbers at different rpm. But less variables using the same exact head type. Still look at Kaase's average torque!
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