First, I appreciate everyone's input. Brent's all over it. One of the things here is that having two builds in one post is getting things crossed up, I likely won't do this again LOL
1 - The 750 vs 465 Tunnel Wedge engine was the one that had the lean second pull, NOT the engine Jay was talking about the top end burble he saw.
It's hard to get into decisions around a dyno in a post. I'd have to write a book about what we discussed and everyone who runs on dyno knows, dyno day is development, but sometimes there's more than just trying every possible combo unless you are in Kirk's racing scenario or the herculean effort Barry and Blair did on EMC. However, we didn't miss the A/F in the least. In fact it was THE reason for the decision to stop on the 750s. As I looked at a loaner set of 750 carbs, set up for another engine and running well on that engine, the potential cost/benefit to the owner, I made the purposeful decision to NOT go into the 750s because I didn't think the cleanup would yield enough HP to warrant a purchase of a second set of carbs.
In hindsight, that should have been in the original post.
I think there might have been some small gains in power with the 750s, but given the existing carbs had exceeded expectations by almost 20 HP and nailed the peak RPM (and shift point) without going fat, it wasn't a tough call for me. Now, if the 465s didn't have clean pulls, we would have been all over the 750s. Believe me, I told the owner (repeatedly) not to expect much from the 465s. I ate crow on that prediction. As most others, I honestly expected the 465s to go pig rich at the top of the pull as the booster dealt with that airflow and anticipated that correcting the HSAB would give us fits down low. None of that happened...if we swapped heads from one engine to the other, with the right cam for the new combo, I think it would have been a different story, but that's bench racing. I hadn't used these carbs before, but they behaved far better than the old flamethrower tunnel ram mechanical secondary 450s.
2 - The right side being slightly leaner seems to be a characteristic of this dyno, and relatively consistent for this day, although not always the case as I look back through other builds.
If you look at mine and Brent's posted pulls, it seems to be a constant variance left to right. Sometimes it's tighter, sometimes not. I can't answer to that, but we did pull plugs after that Tunnel Wedge pull and expected them to show some distress, they did not. In fact, I think Brent's comment "is it yellow and glazed?" as I pulled the plug out of that side. I did not switch O2 sensors, but if the leads are long enough, that is a GREAT diagnostic tool.
Believe me, as a guy who really only does pump gas builds, that is where I focus, and yes, lean can get you sideways, but needless to say, mixture is not the only thing that drives detonation and the engines are really right (tight quench, the right plugs, any potential hot spots cleaned up, conservative compression and good cam and ignition timing) with room for gas variance, plus in the car, it generally fattens up a bit
I suppose that if we are going to hang some data, we all better be ready to answer up for that data, but considering there are hours in the dyno room, sometimes some critical points or money-based decisions are dropped off in the minutes of hanging a post
My biggest punch line on these builds yet again is: Good heads and chambers are the easiest path to big numbers The difference in these two is not only power though, look close at the two pictures for which belongs in a late 60s/early 70s ex-Ford racer and which belongs in a custom rack & pinion, Chevy 4 speed electronic tranny, 4 linked street Galaxie. I did put these two as a comparison, but they don't really compare in use.
