That is why once VVEL cracking is finally done, the market for aftermarket parts opens wide for head work and parts. Valves, springs, retainers, manifolds, etc....

Good point!


But as with every other parameter, I'd be surprised if Nissan left nothing on the table in terms of VVEL tuning.

very likely. since IMO the vq has gone as far as it can in terms of performance. nissan has squeezed everything they can outta this engine platform

I think if Nissan wants more out of this engine package. They will have to give it a bigger bore, a shorter stroke, and a higher red line. The goal should be 100hp per liter. IMO

Direct injection, higher compression ratio, stroke it to 3.8-4.0L and it will be putting over 400 crank hp. With bolt on mods, we are getting around 400 crank hp. I just want to see evolution from design to design with a meaningful impact on performance.

100hp per liter is Honda talk because their cars are slow unless you build them for boost, even then their power range is like 6k-9k and that's it. We can get that 100 hp per liter with an exhaust, TP's/HFC's and an intake.

If they had there'd be no point in bolt-ons and tuning.

Valve timing and lift affect emissions as well as peak torque -- the NA gains may turn out to be modest, but I get they are there for the taking.

If another hr on the dyno playing with VVEL could net even another 5-7 whp at various points in the rev range, I'll take it.

I'm still fairly convinced that VVEL tuning is part of why Nismos tend to dyno a bit higher.

EDIT: ^^^^ apparently, I was completely wrong on this one! See further here http://www.the370z.com/tuning/84786-...ifference.html

Guess it was really just the exhaust -- SH0velman was correct!

Also, I can indeed confirm that the H-pipe Nismo take off exhaust makes good power and is superior to the Weldina Y-pipe Nismo cat-back.

The 100hp per liter is not Honda talk. I come from a motorcycle background, and that was what we use to shoot for. Now it's 200hp per liter. When you talk NA cars, that's another story. A stock 370z is putting 350hp at the crank. That's still 20hp short of the 100hp per liter mark. Remember we are talking about STOCK with NO add-ons. You really want a figure to shoot for? How about 180hp per liter. That's what the 1000cc BMW is putting out at the rear wheel. That would mean a 3.7 liter motor putting out 666hp. :D To get this kind of power. Big bore, short stroke, high rpm. Just like the bikes do it. :D And your power would begin at 5,000rpm, with NO bottom end. :(

Is short stroke the reason you get no power until later in the rev band?

It's one of the reasons. Cam timing, profile, overlap, etc, intake runner length and diameter, header size, etc.

Motorcycles are indeed a different story. I say Honda talk because it sounds better than it really is for them. It's kinda like steak... Steak is good, Honda's are a flat iron steak, and Ferrari's are Kobe Beef. To Honda guys, steak is steak... until you can actually afford Kobe beef. All of a sudden, that flat iron steak isn't so appetizing.

Yeah, I know where you're coming from. ;) Still would be nice to shoot for 125hp liter. That's 462hp for a NA 3.7 at the crank. :D I think the factory can do it. Then they would have to beef up the rest of the drive train $$$. Plus what about the warranty. LOL

We need to get on TVR's level.

Straight six, 4 Liter, 400 horsepower. NA. 100 hp per liter would be gold. This was stock, too!

Too bad TVR is dead.... damned smolensky.

This is good news and hopefully fairs better than BMW's valvetronic (the exact same as VVEL but on the market since 2001) for aftermarket performance tuning. The tuners over at BMW have been mucking around with this for some time now and have had decent results, nothing amazing.

It's interesting to note that both Nissan and BMW decided to not use this technology on their high performance models, M series and GTR. However I think BMW started using this on their M trim Xseries and on some future normal Ms.

I suspect we won't see it around for long.

Funny how one of the first thing on the grand-am rulesheet for allowed modifications for the z34 is the z33 HR head swap :nutswinger:

I could be wrong, but I thought I saw a VVEL video that said it's superior to the Valvetronic since there's no valve springs that will float (harmonic resonance) and drop a valve at high RPM.

Makes me wonder :rolleyes: