At some point you will experience valve float: the valve lifters lose contact with the cam lobes. Members might install stronger springs to overcome the momentum of the various valve train components.

 

on a regular vq35de, the IM i believe is the main limiting factor with power production in the upper rpm range. w/ a better IM, you could potential have a linear power band that makes power to red line.

 

not really the case at all. My own car makes power all the way to redline, using a stock IM and a very small spacer (smaller than most people here use).

The limiting factor is not one single thing, but a multitude of things

 

to further claify my question, I know that you don't gain any power from it, just wondering if the power you be less in one rpm range, to be distributed in another rpm range, sorta speak.

 

I have dyno proof and dont need your "heat soak" input as I live in the desert where temps get to about 125* in the summer

I also have a Greddy info meter and have monitored my IATs thank you very much....once moving the IATs are very stable and with Varis duct I would imagine they would drop significantly ....however in my dusty climate I am still debating the benefits vs drawbacks

I dont race in bumper to bumper traffic and could easily spray the motor down with water if I was drag racing...the short ram intake makes power....period....has on all my cars including this one and many other drag racers

The short answer is

You can increase your AVERAGE hp if you up the rev limter with mods that allow you to at least hold the torque to redline....ie intake/plenum being the easiest, cams being the best and hardest/$$$

most people who are increasing their redline are also planning on mod'ing their intake/exh --- seeing how expensive it is to raise the rev limit I dont see why anyone would raise the limit on a completely stock car considering how well even small mods will effect the upper midrange to redline....but with the low cost of intake mods why would someone stay 100% stock?

 

yea im not with the whole popcharger with the already velocity stacked 06 intake and see the pop charger being a drawback especially compared to the stock intake KNN and a varis duct with the connecting tube. BUt oh well my .2cents. I def wanna raise my rev limter to about 7.5k and tune the exhaust cams to get more power out of the revup but not everyone knows or even uses osirus so hopefully more people would get involved because to my knowldge its the only unit that can control exhaust cams and intake cams right??


im hoping the cosworth intake shows us some gains uptop we havent seen yet.

 

Yeah, poop charger blows. Most people in the know will recommend against it, including vendors on this board. Plus most of the tuners / builders in japan retain the stock airbox. I wonder why?

Wired24/7 ran some IATs with and without the poop charger, and demonstarted it did in fact heat soak.

After ditching my own poopcharger in favor of the '06 air box with dropin, my car now runs much more consistently... The loss of hp from the poop charger heat soak was annoying.

 

And exactly how much power were you "losing"

Stagnant heat is one thing.....once moving the heat is a non issue especially with a duct....if anyone was planning on drag'ing a simple water sprayer would take care of the heat soak from not getting enough airflow to cool the motor in the lanes

Short rams make power....drag racers use them time and time again in street cars and they run short rams out of headlights if they can....

If you want to worry about heat on the street go ahead....but from ambient to final IAT the popcharger isnt as bad as your claiming it to be....I never said it didnt soak but does so in traffic/slow speeds.....for a time when your going to measure acceleration say 1320 feet...a short ram will work very well with a little water spray to cool off the hot intake parts like the manifold/plennum....once moving the air spends so little time in the engine bay to cause a detrement such as the one you think

If you drive in traffic rock an airbox/drop in....a conefilter simply outflows a square filter.....straight from K&N...enjoy

Whenever possible, performance enthusiasts should install a K&N 360 degree open-element filter. A correctly sized conical or round filter will deliver virtually unrestricted air flow. And, as we have learned, providing the engine with all of the air it needs promotes optimum performance. In a high speed application, a K&N filter will straighten the air which counteracts turbulence

 

Water/ Meth spray on an NA car?? Wouldn't it be easier and more effecient to just use the stock box & dropin to address heat soak? OTOH, on an FI engine where you actually need the flow of an open filter, meth injection is appropriate - but not on an NA engine. You'll have better results with an oil cooler and aftermarket rad / thermostat. What a tard~

BTW, how much hp do you actually think you're sporting there with your non-tuned, stock plenum, stock lower collector, stock headers, stock cats, stock exhaust?

Oh yeah, I forgot you have a heat-soaked poop charger and TB spacer that produce 0 whp and can actually LOSE whp... Lol!! But, I'll admit they do look pretty, if you're into form over function. Some people refer to that as RICE... As for the 280whp you claim in your sig - I call total BS. :-)

 

keep in mind its on a dynapack as I recall. The gains are the gains relatively speaking, but the final # won't be duplicatable on another dyno

all these debates on one intake vs another are hilarious. The fact of the matter is NONE of them do a damn thing in the grand scheme of things....none. They do sound nice though

 

and most japanese race Zs i seen use stock airboxs with modified intake tubes and samco liek hoses . Must mean something about the 06 intake. I can understand its use in older Zs but the 06 looks to be set. but Z1 is right....its really nothing in the bigger picture.

 

I want to raise my for autocross. I have an 03, what is the highest I can raise the rev limiter without hurting anything.

 

You can hurt the engine without raising the limiter. It depends on how much time you spend at high RPM.

And some engines will take it better than others too. So there is no solid answer.