i still would love to see a vid of a race of a revup vrs a revup with teh 5/16 mrev 2 combo and a 1/2 spacer combo. really tht vid will be the deciding factor . Making that much underthe curve it should be signiifincant differnce and the 1/2 spacer should pass all in the top end with the stock revup passing the 5/16 top end aswell but owning both low end.


This is the race im down for. Im a stock plenum revup however i have M cats and exhaust. So i would love to race a mrev2 5/16 combo and a 1/2 spacer combo.

Im leaning towards the 1/2 spacer but want peak power more then anything right about now . TQ on this motor is obviously wasnt its main goal

 

I pointed this out a while ago. Why spend so much money going backwards?

Check this for a nice comparison:
https://my350z.com/forum/na-builds/3...up-mrev-2.html

 

And you pointed that out incorrectly a while ago too.
Even the "game set match" dyno plot you refer to in your link clearly contradicts your assertion.

When shifting at Redline on the REVUP engine:
Do you know what the rpm range is for each gear? (this is important to know)
Do you know (roughly) what the average rpm is for a road course race?
Or the RPM range of each gear in a 1/4 mile race?

I will post the data if you don't already know.

 

You are aware that that dyno plot actually goes higher than 7000rpm, but according the the thread, it didn't print properly. Meaning as the RPM's rise, the car is still gaining on the Mrev manifold.

 

And if you havn't seen where it goes past 7K, they both plateu and level out. I've seen a similar comparison dynod to 7.5K and they remained constant. They dont continue to diverge.

But since you didn't answer the questions in the previous post, the answers are given below.

But first, something about your selected dyno plot comparison you referenced is not normal... It doesn't have the charecteristic signatures of a usual dyno plot comparing MREV2 and a stock revup lower collector.

There are two things about it to recognize.

1) Take note of "Area A".
It shows the revup lower plenum as having more TQ down low?
That's not normal. The revup lower plenum never has more TQ that far down. Never. So something is off or different about the comparison. I don't know what is making it different but its is.

2) Take note of the TQ or HP curve at 4500 RPM.
There is uaually a very large delta between the two in this area. The delta should be no less than 15HP / 18 TQ. And often is around 20HP / 30 TQ.
So something about this comparison is off relative to normal. I don't know the reason is, but its there.

Was it the tip in? Changes atmospheric testing conditions? Different engine internals? Cams? The ECU playing games? Is this plot from JT's super NA build?

I can't say why, but either way, the MREV2 always has more TQ down low. And even if it was JT's NA build, it clearly is faster with the MREV2.

Aside from that, we both agree the area of concern is the HP up high. Correct?

And the dyno plot you refer to is farily typical in the high RPM range so we can make a valid comparison from 4500 and up. ...Do you agree?

So take a look at your referenced plot with the RPM range of each gear shown.



The RPM range of Second Gear, Third Gear and Fourth Gear.
On this plot it shows the RPM range of each gear used while racing and shifting at redline.
When the RPM range is highlighted against the power curve, a clear answer jumps out as to which makes more power.

So I must ask, "How could it be concluded that the red dyno plot line (with a stock revup lower) is superior to the blue dyno plot with the MREV2?"
It doesn't make sense.

Area "B" has more "area under the curve" than Area "C". Do you agree or disagree?

The comparison comes down to Areas B & C. Even without a spreadsheet analysis it is easy to see which has more area under the curve.

You are saying that trading the area under the curve "B" for the area under the curve "C" is better or faster? ...The net effect would be a significant loss of power for each gear.

And when you consider 4th gear ends at about 6125 RPM in a quarter mile race at about 103 MPH, based on your referenced dyno plot, the revup stock lower collector has a complete loss of power all through 4th gear.

The car is slower and less powerfull with the stock revup lower collector.

Explain how you disagree?

------

For a different comparison, consider the effect of MREV2 in Road Course racing.

The difference here is even larger!

Look at the attached Cipher data logging below. It is a logging of engine parameters while racing at the Spring Mountain race track in NV.
We can ignore the last cool down lap so look particularly at the RPM's between ~20K to 80K ms and make a visual guess at what the average RPM is...

Another thing to consider is that while the average RPM tells us a lot, what we care about more is RPM when the pedal is slammed to the floor WOT and using all the available power. Partial throttle is irrelevant because either plenum can make the same power at partial throttle.

This data was entered into Excel for detailed analysis. The actual time weighted, WOT, RPM average as analysed in excel is 5630.16 RPM.

5630 RPM is the most used, WOT, RPM while road course racing. And yes, this value will vary from track to track and from driver to driver, but it won't vary that much.

So now that we know the engine spends more time at WOT @ ~5630 RPM while road course racing, take a look at the dyno plot again.

5630 RPM is right smack in the middle of area "B" of the MREV2 dyno plot.



So on the road course, the MREV2 is roughly 10+HP superior to the stock revup lower collector. ...Even if its JT's NA build.

On the street the MREV2 is faster.
On the drag strip the MREV2 is faster.
On the road course the MREV2 is faster.

If you don't agree, please elaborate.

 

If you would like to see more of the track data or different parts of it just let me know. I'll re-plot and highlight any part of it and post it for you.

 

Now, try it again with the a 8000rpm redline, and Revup making peak power at 7200rpm. That is, afterall how the car is set up.

 

give up man....

 

Are there any tunes done to help achieve the hp/tq increase in these graphs?

 

I don't make mods for the half dozzen NA builds on this forum. I make it for the vast majority of people on this forum. And they don't make NA builds like Jeremy or Adam.

Besides... Of the ~half dozzen or so NA build cars on this forum. What fraction of them are using revup lower plenums?... Less than half?
Adam tested the revup lower plenum on his car... but does he have one on his car now? No. Does his engine rev to 8K? Yes.

The revup plenum was never a good engineering design from a performance point of view. It was a marketing decision.

It bumped up the peak power at the sacrifice of power everywhere else on the curve. This allowed Nissan to increase their power rating from 287 to 300 HP.

It made the car look faster on paper. 300HP!
It makes for better advertising in the magazines and it gets the arm chair racers excited but that's it.

The only reason the revup engine was able to keep up with the non revup engine was because of the extra 500 RPM. The extra 500 RPM on the RPM shifting range compensated for the loss everywhere else on the curve and it ended up being a relative wash. (But now it looks better on paper)

The revup and non revup engines have the same "average" power on the dyno.

But when you put a MREV2/spacer on a revup engine, it makes more power than either. Its what Nissan should have done.

 

If that's Jeremy's NA build, the answer is YES. To the extreme.

A completely rebuilt engine from top to bottom. 15:1 compression too.

JT's car is on of the rare examples of a NA build.

 

its a 4th gear diff

 

i noticed after about 150miles

 

Yes, Jermey's build was a All motor build up. But as far as I know, no tuning was done in between swapping the manifolds.

Tony,
I'm trying to be objective, but it just appears you are only interested in protecting your product.

Jeremy's car dyno is not an isolated incident.



The car has no tune, and is running lean. Again, an example of a Rev up making more low end than the Mrev2. For about 700rpm, the Mrev2 really makes itself known over the Revup, but with a tune, I don't see it being that big of a difference.

 

Correction: Similar low end.
The revup, and its manifold is how nissan should have done it in the beginning. A longer, broader powercurve overall.

 

Powerlab making use of the Revups high Rpm breathing.
too bad we can't see the torque improvements.

 

If you are trying to be objective, answer the questions in my prior posts.

Please answer them. An objective discussion has questions and answers on both sides.

And sure, I will advocate my product within the limits of fact.
Being a vendor doesn't automaticly exclude me from being objective. In fact, I have to maintain a much higher level of honesty and objectivity because I am engaged with this forum. Why? Because liars always get flushed out on the forums.

I understand the importance of testing with controled test conditions. I've seen what a lack of controls can do to dyno plots.

...Objectively, even in the MREV2 plot you reference above, where the testing was done on different days under different conditions, the MREV2 is clearly making a greater average power.

You don't objectively see that in both of the MREV2 plots you reference? (please answer this question)

It appears to me that even though both of the plots you reference don't support your assertion, you refuse to accept them for what they really show.

You said the MREV2 kills top end. You reference two dyno plots as evidence. And both in fact show a clear increase. Either you refuse to be objective to save face or you simply can't see it.

I havn't thrown out unsupported assertions or conjecture, diverted or changed the subject. I posted actual track data, actual gear/rpm ranges under race conditions and detailed analysis far, far beyond what any other vendor ever does.

If your own referenced plots don't convince you, and you won't answer objective questions where else can this discussion go?...

PS - as I was writing this reply you posted another unrelated plot for a different subject. That is a different topic for a different thread. Start a new thread if you want to discuss it.

 

This is your referenced plot KA24DE.

What do you see in it?

 

No one is arguing that the mrev makes good mid range power, but it is clear on BOTH dyno plots I have posted that you are losing top end breathing. You cannot argue that.

Both cars on those dyno's were tuned for the Mrev manifold, and not for the rev up. And on both dynos the Mrev makes a good amount more mid range power for 1000rpms, and then for the last at least 700+rpm, the Revup manifold (that hasn't been optimized for that setup) makes more power. You can't argue that.

Add a higher redline (which some do) and breather mods, I just can't imagine the Mrev manifold being a better choice.

 

Its a Revup, redline is 7100rpm, it must have hit the speed limiter.