Not sure what they charge for the hour -- call them and ask?

I won't be on the dyno for a while -- kind of run out of things to do until I get into tuning.

I will have to locate my chart from Proven Power as well. I did a baseline and another with the JWT pop chargers. However, in my next run I will have GTM resonated Test Pipes and the Agencey Power CBE. The only thing I am not sure about is whether I will need a Y pipe or not...... I have a message to the vendor I purchased the CBE from on Black Friday asking whether this is the case.

:driving:

Did you pick up anything from the pop chargers?

I did think of one (highly unlikely) possiblity of why my intake experiments didn't work: I suppose I might have been outflowing the MAF sensors. If the MAF hits (or even approaches) 5 volts, the ECU will go to 100% duty cycle and that will quench power in a hurry.

One piece of evidence supporting this hypothesis would be if aftermarket intakes tend to ues a wider than stock diameter tube.

The wider diameter will slow down airflow, giving the MAF a lower reading. This would also keep the sensors from hitting 5 volts if it would have done so using the OEM diameter.

Anyone know the inside diameter of their aftermarket intake?

Actually, Jordo I need to call Proven Power to give you permission. You will see my initial bone stock runs vs. the pop chargers. I actually made gains - between 3 to peak of 7 HP through out the curve. Note, however this was my first of any engine mods. Also, note that I did not have any heat soak period .. so in actuality my gains make sense.

Do you know off hand if my JWT Pop Chargers have a wider circumference compared to the stock tube?

No clue. OEM inside diameter is about 57 mm or ~2.25 inches

I just spoke to a good friend of mine who tunes Z's and he said (1) The OEM MAF sensors are good to about 600 whp and (2) apparently these sensors are versy sensitive to airflow tumble effects. Thus changing the shape or orientation of anything in front of the MAF sensors will cause misreads, resulting in running either overly rich or lean :icon14:

So... that is most likely the problem.

In theory with further experimentation I might find something that works, but instead I'm just going to be happy with my current set up as is (for reasons I expand on below...). Glad I experimented, but not interested in continuing the project.

If someone else wants to play around with it, I have the OEM intake MAFS tubes for sale -- perfect for a custom intake project http://www.the370z.com/parts-sale-pr...afs-tubes.html

The gain of 3 - 7 whp from the pop chargers is on par with the panel filters, and based on the dynos I've seen of other folks, on par with every other intake (double digit claims never seem to pan out unless it is the only modification for whatever reason).

You'd think more could be achieved, but I guess a combination of underhood heat and orientation problems make improving significantly on the factory airboxes more challenging than one might expect.

Yeah, man, if you could ask Darrell to share them with me, that'd be much appreciated. I like data :tup:

So does this mean the HPS tubes aren't worth it either? Best thing to do is just get some drop in K&Ns. I noticed a difference from just putting in the drop ins especially up top. Seems to breathe better at the higher rpm range as to before it seemed it bottomed out went flat.

At this point, I'd say not really. Honestly, I may eventually just sell mine off.

I found at best a 2-3 whp (i.e., ~1%) gain at peak with evidence of a 2-3 whp loss at other points and no change throughout most of the rev range. Never mind the possiblity that such a small change could be due to measurement error...

That's a dubious endorsement at best... :ughdance:

I'd say, the HPS tubes couldn't hurt, but they won't be much of a help over the K&N drop in's alone either.

On a budget, the K&N panel filters by themselves are definitely the way to go.

Finally tuned! :tup:

Mods = HPS tubes [somewhat worthwhile], K&N panel filters [worthwhile, considering how inexpensive and easy to install!], ebay test pipes [best bang for the buck!], S-tune cat back [small gains, but lovely sound], and of course a good tune [very worthwhile -- great gains!].

SAE corrected numbers. Uncorrected, this was 305.

http://www.the370z.com/members/jordo...-plus-tune.jpg



The somewhat overly optimistic STD correction (my new "bragging rights" dyno :icon17: )

http://www.the370z.com/members/jordo...ights-dyno.jpg



A comparison of where I was before tuning (i.e., with all other mods) and now.

http://www.the370z.com/members/jordo...thout-tune.jpg



The detailed camparo shows pretty substantial gains in torque down low (as much as 10 lb-ft!) with generally good gains overall throughout the entire rev range (5-9 whp).

http://www.the370z.com/members/jordo...ed-comparo.jpg


And last but not least, a comparison of where I was bone stock vs. now :D

http://www.the370z.com/members/jordo...ods-w-tune.jpg

Oh, summary of gains from all mods, based on SAE corrected whp/wtq at 5252 RPM, when hp and tq are equal...

Bone stock = 219

+K&N panel filters = 222 (+1.5%)

+Test pipes = 232 (+4.5%)

+S-tune catback = 235 (+1.5%)

+HPS intake tubes = 238 (+1.5%)

+Tune = 244 (+2.5%)

Cumulative gain @5252 RPM from Bone stock = 25 (+11.5%)


Again, this is just a summary of changes at 5252 RPM's, when hp and tq are equal. Although gains will vary in hp and tq throughout the rev range, this should be a good indicator of overall gains.

Individual results may vary... :icon17:

Note: I'm surprised to see some evidence of gains for the HPS tubes looking at the data this way... I'll upgrade my review to "somewhat worth it".

Great Job Jordo!! I apologize, as I completely forgot to call them to grant you permission to my run files. However, now that I've got my own test pipes and exhaust, I may as well do another run. Maybe this weekend even? .. We shall see.

Cool -- thanks, man!

Past runs from when the Z was stock would be great too!

The data is really helpful to get a clearer sense of what the Z puts down, loses through the trans, gains from different mods, etc., which is something we all want to know ;)

Sure thing Jordo .. I will grab all of my files today .. going for another 3 pulls .. I haven't had a chance to get the dyno since I installed the TP's and Exhaust.

At the risk of sounding like I'm just trying to raise PP's profits, I would consider springing for 6 runs.

I find that it takes a few runs to get the ECU to readjust fuel trims and such in order to see the gains of bolt on's.

Probably has to do with the ECU needing to see a certain range of load in a given gear to actually make adjustments.

Just saw this thread. Very good, thanks for posting and taking the time to do this. You may want to post in the engine section. I think it would be useful for others to see.