This is the AM Performance 370z Nissan refers to on Facebook. It has the HR heads...

AM Performance 370Z Grand Am Race Car on the Street - YouTube

Well, a car may have done it, but that doesn't mean it's best, especially without knowing any reasons why they chose to. For all I know, the VVEL isn't legal in their race class? Or maybe their engine management system couldn't control it anyway so why have the extra moving parts floating around.

Continuously variable timing and lift on the valves is superior to static valve events or merely cvt. Unless there have been examples of mechanical issues with the VVEL at the engine speeds required to produce 400hp NA, then it would require some test data/explanation to come to the conclusion that removing the VVEL has any benefit. I see no reason to just assume that simply because one car has done it, without some sort of case study.

What ever happened to the thread he had going on that Nismo Racecar? Seems by facebook and here AM performance fell off?

"Because racecar"

interesting.... sub'd

I wish we had more info on that AM performance car.

I kind of take it as a bad sign that we don't have additional information. They filmed a few youtube videos last year and sounded as if they were ready to go mainstream, that was last year and we haven't heard a peep. I guess the heads conversion didn't out as good as they hoped.

Sounds like a lot of work for marginally better flow...

tuning the VVEL -- even with a new cam grind -- would probably work out better and be easier to do.

whos to say that the VVEL even needs any tuning for NA applications? If my assumptions are correct, its probably already on a closed loop feedback system for peek volumetric efficiency for the given RPM and load. If thats the case, I dont think there is much room to gain anything from it for NA other than perhaps a more aggressive exhaust cam. Unforunately we do not have a lot of solid information into its calibration or decision making process... however it sure as hell seems downright effective if you compare power and performance to DE's and HR's. Also consider this... bolt on mod combos are making 30-40 HP over stock on the dyno. That means the engine is up to 370+ HP with bolt-ons. That is acheiving 100hp per liter or more, at only 7500 RPM redline, with outstanding powerband and driveability... while being able to achieve ULEV status. Thats is a greatly efficient engine and at decently low RPM to be able to make such HP/displacement.

This is why it is rather unclear to me why people are so excited to either ditch VVEL or attempt to take control over it... it really appears to be doing quite well, and I would need to see some real proven data on where it is falling short before I would even think of screwing with it.

:iagree:

I wonder why Nissan even had the HR head conversion as a option in "Project 370" if it is such an unproven mod ?

It remains unknown... as you noted we don't have enough hard data on its range of operation -- BUT, we do know that the max lift within the programming appears to be well below what the valves are physically capable of achieving. Whether or not that will make more power is an empirical, and largely unexplored, question.

When you don't know the degree to which it can adapt, you can't know whether or not it's optimized for best power on all set-ups.

Even if it "learns", if it works similar to fuel trims, we all know that no ECU can "self-tune" as well as a human who can test variations on the factory tune on a dyno.

In the end, it presumably has some fixed targets, and operates in a closed loop around them by creating transient modifiers (i.e., "trims").

Is it optimized for best power? Who knows? It remains a black box for the most part.

I understand all of the back and forth on "is it worth it or not" but at the same time I think I am a little confused on what Nissan is saying.

If Nissan themselves is stating that you can swap the heads for cams to get a more aggressive setup, wouldnt that statement in itself tell you that Nissan knows there are limitations with the VVEL?

I mean just doing a little bit of reading between the lines, it seems as if they know there is a limitation and that swapping the heads to allow for cams is the fix to that. I dont understand why Nissan would tell Nissan Factory Supported race teams that it would be beneficial to swap the heads out if it wasnt...

I think youre actually reading too deep into some marketing project.

As for the Nissan Motorsports HR Head conversion... is that even an actual viable product that you can puchase from "nissan motorsports"? If so, anyone have a link to where "nissan motorsports" mentions this "product"?