Ok, so what would it take to "upgrade" my air intake on my TCH. I've been reading all about cold air intakes, short rams, and whatever, but for instance, the K&N systems won't fit under the hood of the TCH because of the hybrid system.

So, can the existing intake be (easily?) upgraded or augmented to increase air flow?

 

I didn't worry about the kit, I just added the K&N filter to the stock system.

 

I am all for air intake upgrades and have done it in my past vehicles but in a hybrid where the ICE is uses maybe 75% of the time thus making increased air flow not as cost effective?

I have not convinced myself yet and figure the plasma TV is a better investment (for me).

BUT, if you do it, please let us know how it goes!

 

Just an educated guess, but doesen't the greatest benefit of these "improved" intakes occur at full (or close to full) throttle, or at high RPM?? That would seem contrary to the overall concept of the TCH to me. Just my thoughts.

 

CAI & K&N....modern day SNAKE OIL.....

Unless you're "tracking" your TCH then 99% of the time the throttle plate is the MAJOR restriction to intake airflow.

CAI...??

There is an IAT, Intake Air Temperature, Sensor in the intake path so the A/F mixture is adjusted according to ACTUAL intake air temperature. The only time "COLDER" air might make a difference is when you are at WOT and the COLD/DENSE(r) intake airflow would result in a FULLER, more complete, A/F CHARGE in each cylinder.

 

Mickieboyblue is right. Buy a plasma TV. Or an LCD TV. Increased airflow means increased fuel flow (since ratio must remain constant) and therefore decreased economy. And economy is the goal of a TCH.

 

"Increased airflow means increased fuel flow..."

NOT...!!!

Well, logically yes, but in practice NOT.

Decreasing the restriction to airflow, or ingesting cooler (denser) airflow has, in practice, no effect on FE. It just means that the throttle valve would be more "closed" for a given level of engine performance. Increased pumping loses and lower engine frictional loses, net effect on FE probably aught/zero. The only time this would/might make a difference is at WOT wherein the total charge, FULL charge, "stuffed" into each cylinder would be higher/greater.

 

In simple terms....

A Cold Air Intake isn't good for a hybrid, as you want to keep the engine as warm as possible, also you don't need the extra air density. (Notice I said Need) This isn't an issue of getting more power.

As for a nice K&N Filter, yes, they flow very well. *IF* you service them correctly. There is an advantage to a free-flow filter. I wont go into the physics of Volumetric Efficiency, but the bottom line is that you want to reduce the power wasted trying to suck in the air. In a normal I.C.E. you are trying to reduce the amount of energy wasted on the intake stroke.

Think of it like this; take a shirt and put a single layer over your nose and mouth. Now breath. Next, double the thickness and breath. Now you have increased the amount of energy required to breath in.

Here is the catch. The TCH is NOT a Otto-Cycle 4-Stroke engine. It's also not a true Atkinson-Cycle. What they have done is taken an Otto-Cycle engine (Normal 4-Stroke... Intake, Compression, Combustion, Exhaust) and modified the intake valve timing to mimic that of an Atkinson-Cycle. What that does is allows the intake charge to be PUSHED BACK OUT of the intake valve during part of the compression cycle.

I haven't done the math on this... I'm sure that I will get board one day and do it. But I have a strong feeling that a more free flowing filter may cause a fairly large change to the overall MPG. It's very possible that allowing MORE of the intake charge to be pushed back out is going to REDUCE the overall power of the I.C.E.

Now, you may be thinking "Hey, that's great, less power means less fuel." But wait, what about the battery. That would mean MORE electricity is needed, and ultimately causing the I.C.E. run more/longer.

SOOOOO

Who is going to put out the $50 for a K&N and the $75 for a take of fuel and try it??


(Any thoughts? Comments? Corrections? Please... if you are going to respond, be nice and be accurate. if you don't understand ALL of that.. don't respond.)

 

Info on the HSD:
http://www.toyota.co.jp/en/tech/envi...Reports_12.pdf

 

Thanks for the input guys! Very helpful, I love this forum. As a non-car guy, you're a great resource for the automotively challenged.