| Greg- I've made a couple main points and I've provided sources to support them. If others care to argue, then we'll have a discussion. I'm not going to obscure my thoughts with vague sentences to appease those who want to argue. I just hope they provide references as well so that we all learn something. To restate, one main point was that the short side radius on the 30p is more efficient than that on the 40p/48p heads. I'd still argue that the 30p is the more efficient head (stock for stock). Speed Specialties will probably support this theory. They have decades of experience building performance forced induction and NA engines. I've studied cut-away photos, many port pictures, and have read numerous articles from various publications as well. I'm very confident in this claim. Again, it's been a 5 month long process in total. Here are more links: [ http://www.speedstore.ca/head_porting.html ]
[ http://rehermorrison.com/tech-talk-70-airflow-fallacies-avoiding-the-pitfalls-of-the-flow-bench/ ] Where did I argue that the stock NA heads provide higher total CFM numbers? I never did. Feel free to follow my build thread on 3ZC. [ http://www.300zxclub.com/showthread.php?t=224851 ] I'll post the results here as well for all of your convenience. Maybe you've uncovered a big flaw in JWT's mild cams or in regrinding in general. Please post some dyno pictures or references since you're making the claim here. This rebuilding book doesn't recommend against reground camshafts in general. Many people report success stories running reground camshafts on other engines. La-Z-Link Are you suggesting that anomalies in the power band are consequences of a reground camshaft in general? Do you have dyno graphs from other engines that are running reground camshafts? If regrinding is a big problem, it would have big implications for almost all 4 stroke engines! Or are you saying that there is a problem with JWT's grinding machine or profile? Now this isn't personal, but I feel it's important to state: You run a shop. Every shop has a financial interest. Even if you are the most morally righteous guy on the planet, I would still doubt your professional claims. If I didn't, I'd be a (poor) fool. In the end, we all have our own financial interests. Consumers wish to pay the least amount of money possible for a reasonable product. Businesses desire to maintain a good profit. Some shops prefer to sell products that provide higher margins. This is the reality of any business. I'm not criticizing you for it. However, this is also why I'd expect to see some data to support such a claim even when it comes from you.
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