CP-e MAFci : why not ?

[PXLpainter]

I think the ECU and slushy Tranny are going to be the weakest link in anything we do to the Gen 2

If there was a 6 spd manual tranny that would fit, I'd be all over that before any boost on the engine right now.

[PhreakdOut]

P.P.S. Just to be a pain for Phreak, there is a minor difference in how the two pipes would flow. Bernoulli would have something to say about your post.

Down2TheC is right there. For one, air (as a gas) is compressible, whereas water generally is not. While air is being drawn in, there is suction through the intake which can cause compression of the air. If you read up on your fluid dynamics, you'll see that air is considered a compressible fluid, whereas water is considered a non-compressible fluid.

Which is why the comparison of an intake and a water pipe doesn't work.

Thanks swindler ... I way over simplified the discussion. It's been a loooong time since fluid dynamics. I'll try to dust off the brain a bit and see if this can make sense at 2:00am.

Rather than focusing on Bernoulli's equation which takes into account the changes in the density of dynamic pressure, I spoke too much to the throttle body and its volumetric flow rate. You are very correct about compressable gases being the difference. In this case, rather than dealing with forced induction such as a turbo or supercharger, the engine determines the static pressure of the charge. (For this discussion, we'll assume a constant RPM and temperature) The question here might be if the static pressure of the intake charge from the engine (generated by the pistons on the intake stroke) will draw more air (in other words compress more air from the intake pipe side) from the 3.5" pipe versus the 3" thus increasing the total pressure. My hypothesis (with no real data in hand) is that the engine can not draw enough air to make a significant change in density when you are dealing with intake pipes of this size. The difference between 3" and 3.5" in this case would be the same as 3.5" and 4.5". Different acoustics but no increase in density. Thus no performance benefit.

Make sense? After retyping this a few times into a 3"x5" window on my screen, I have no idea anymore. LOL
Let the debates begin.

[Sebas007]

My engineer pal told me the samething about water compression. He told me that he learn that it wasn't compressable at all but in more avanced course he learn that it was possible but a very tiny compression...

I know that CP-e made the test with different diamater pipe. 3", 3.5"...I know that with their test and dyno they were getting more power so I may conclude to more air from intake valve.

I would like to be able to argue with engineer knowledge but I can't. I still read a lot of stuff, use my logical mind. I will let the enginneer debates.

P.P.S. Just to be a pain for Phreak, there is a minor difference in how the two pipes would flow. Bernoulli would have something to say about your post.

Down2TheC is right there. For one, air (as a gas) is compressible, whereas water generally is not. While air is being drawn in, there is suction through the intake which can cause compression of the air. If you read up on your fluid dynamics, you'll see that air is considered a compressible fluid, whereas water is considered a non-compressible fluid.

Which is why the comparison of an intake and a water pipe doesn't work.

Thanks swindler ... I way over simplified the discussion. It's been a loooong time since fluid dynamics. I'll try to dust off the brain a bit and see if this can make sense at 2:00am.

Rather than focusing on Bernoulli's equation which takes into account the changes in the density of dynamic pressure, I spoke too much to the throttle body and its volumetric flow rate. You are very correct about compressable gases being the difference. In this case, rather than dealing with forced induction such as a turbo or supercharger, the engine determines the static pressure of the charge. (For this discussion, we'll assume a constant RPM and temperature) The question here might be if the static pressure of the intake charge from the engine (generated by the pistons on the intake stroke) will draw more air (in other words compress more air from the intake pipe side) from the 3.5" pipe versus the 3" thus increasing the total pressure. My hypothesis (with no real data in hand) is that the engine can not draw enough air to make a significant change in density when you are dealing with intake pipes of this size. The difference between 3" and 3.5" in this case would be the same as 3.5" and 4.5". Different acoustics but no increase in density. Thus no performance benefit.

Make sense? After retyping this a few times into a 3"x5" window on my screen, I have no idea anymore. LOL
Let the debates begin.

[Down2TheC]

^^^ Nope... not really. They never tested a 3" tuned to see if it would make a difference. Once they knew they could fit a 3.5" and that the tune was the bringer of power, there was no desire for a 3".

The 3" would produce a negligable increase in pressure head (resistance) since the speed of flow is 75% faster. I was just playin' w/ Phreak.

[Sebas007]

Sorry if I'm wrong...I remembered having read something in this post in the Injen comparaison section...http://www.solaraguy.org/viewtopic.php?p=186107

....Power: CP-E started their development by stubbing in a 3" pipe. They found no power improvement. The fact that you don't have to convert the signal for a 3" pipe tells you that you're not opening up the airway any. If you were you'd get CELs. Injen produced dyno's reporting more power than the 3.5". This is against all laws of Physics!!! ...

^^^ Nope... not really. They never tested a 3" tuned to see if it would make a difference. Once they knew they could fit a 3.5" and that the tune was the bringer of power, there was no desire for a 3".

The 3" would produce a negligable increase in pressure head (resistance) since the speed of flow is 75% faster. I was just playin' w/ Phreak.

[Down2TheC]

^^^ Nope... not really. They never tested a 3" tuned to see if it ....

Sorry to confuse... Tuned is the operative word there. It went...
3" no tune = 0 gain
3.5" no tune = 2-3 gain (flat linear conversion to make the MAF happy.)
3.5" tuned = the 10-12 avg whp gain.

A 3" tuned would probably get close to the same improvement.

And since you dug up that old quote, I should correct myself. The fact that the Injen 2.75 pipe does not cause a CEL only means that the opening at the MAF is the same size as stock. Theoretically you could get a gain by just going to a pipe the same size as stock airbox outlet, but you'd have to have a very restrictive airbox. Apparently ours wasn't all that bad to begin with. (when that lower door was open that is. i.e. Doc John mod. That door was full open at 3Krpm and up.)

[Sebas007]

^^^ Thanks for the good and detailled explanations !

[Sebas007]

I'm curious about your heatshield...did you make the design of it if not where did you buy it ?? What it is made of ? I'm just trying to improve a good product !

again great setup you have there !! Maybe you could have more power with a tuned map...but yeah it would cost a lot of $$ on the dyno.

Thanks for any info !

How about another option- I have a TRD Supercharger and the CPE is created for NA vehicles. I've dropped about 5-8k into this car and another $400 is a drop in the bucket, but for $400 it better be right.

(I think) I'm the 1st guy, brave enough to try the CP-e intake for the GEN-1 Solara on my S/C'd 1998 Sienna. Still using the base fuel map for more than a month and no problems so far. Still looking for a tuner shops to tune my not so ordinary minivan. More power is noticeable after 3200 rpm though you have to be easy on the gas pedal at take off for a smooth acceleration, or occasional jerking will occur which I think it’s the effect of the EBC module cutting the boost at A/T gear change.

Here how the engine bay looks now. I changed the filter with K&N RF-1035 angeled (10 degree) flange and added a filter heat shield.

[siennasc98]

[quote="Sebas007"]I'm curious about your heatshield...did you make the design of it if not where did you buy it ?? What it is made of ? I'm just trying to improve a good product !

again great setup you have there !! Maybe you could have more power with a tuned map...but yeah it would cost a lot of $$ on the dyno.

Thanks for any info !


The heat shield is from eBay. It's made of full polished T304 stainless steel and I think I bought it from this seller:
http://cgi.ebay.com/ebaymotors/AIR-FILT ... 3475QQrdZ1

[WSkids97]

I'm curious about your heatshield...did you make the design of it if not where did you buy it ?? What it is made of ? I'm just trying to improve a good product !

again great setup you have there !! Maybe you could have more power with a tuned map...but yeah it would cost a lot of $$ on the dyno.

Thanks for any info !

Nice little intermission from this heated debate.

Just out of curiousity what constitutes as a strong or weak engine. Last time I checked it was about what parts were in it, cause I didn't get the press release on nissan's new cylinder sleeve technology... Just some food for thought.

[siennasc98]

I took the van for CA Smog Check today. I did not remove the CP-e MAFci intake and the results are all PASS.

[Sebas007]

Excellent !! Do this test is equivalent to the CARB certification ??

I took the van for CA Smog Check today. I did not remove the CP-e MAFci intake and the results are all PASS.