Simota CF650-6 Air Intake Review

[invader166]

Hello everyone,

I bought this intake a few weeks ago, and finally got a chance to install and use it for the last couple of days.

http://www.simota.com/productsinfo.php?ID=80

I searched the forum for a bit more info on it, but wasn't able to find too much, so I decided to write a review on it for future buyers. So, without further delay, here it goes:

Installation:

The kit came with a nice set of instructions along with an inventory list to make the air filter box assembly process, easier. I recommend you assemble it first, before doing anything in the car. Attach the filter to the velocity air stack, tighten it down with the hose clamp, and install it in the air box. Making all the holes for the screws line up can be tricky. Be patient and remember to used the 4 shorter bolts that are included in the kit for this. Tighten them down snug with either a screwdriver or a 10mm socket+rachet/wrench.
Next, head over to your car and remove the factory air-box and air hose. Set the Simota air box through the open space into position. This, again, can be tricky, so again, be patient. Then secure it to the car frame with the included bracket. Use the 2 long screws to do this. I suggest using a 10mm socket and ratchet due to the limited space available.
Finally, re-install the air hose and don't forget to switch over the MAF sensor from the factory air-box to the Simota intake.

Top view:


Hold-down bracket:


Side view:


Impressions:

First, I'll start with the good stuff:

I might be pretty biased with this because this is my first ever intake mod. Up until now I've concentrated more on the exhaust side of things (axle-back exhaust, header...) and haven't really seen super extraordinary results. This mod though, has really improved the engine response. Before, I used to have to downshift to get to a decent speed on the highway quickly. Now I no longer have to do that, and I feel the engine pulling harder in all gears! It definitely gave me some extra horses!
The air filter box seems to do a great job of keeping the air intake temperature relatively low. I'll confirm this with a heat gun. Frankly, right now I don't know what to classify this intake as. CAI? SRI? Maybe both?

And now, for the not so great parts:

The intake will rub on other parts of the engine bay. It's unavoidable and something to get used to. I wonder if that's the way it was designed actually. If you didn't scratch the box when installing it, it will get scratched over time.
Another thing, it's a pain in the ass to maintain this intake. There is no way to check the condition of the air filter without taking the entire box out of the engine bay, and if you do need to replace the filter, then you are restricted to the dimensions of the intake air box. At least the filter that comes with the kit is of a good quality, so you won't have too much trouble for a while.
One other thing. Supposedly, this intake is for lift-back models only, but Simota's website states it's for Vios models from '06 and up. Not sure if anyone tried to fit one in their sedan or not...

At any rate, that's my review for this intake. I hope others with find it useful and informative.

[LTHatch]

Nice review! Did you do any 1-3 gear pulls with it? Curious if its a noticeable improvement in the upper rpm range as it is in the low end passing range.

[rabbito]

i had simota carbon intake..i think its similar to the intake you installed above..lost low end and gained top end, small car like this shouldnt use low end..so i removed the carbon intake and changed to k&n drop in..
i have header, mid pipe installed

[LTHatch]

Rabbito: Any idea why you lost low end with it?

[invader166]

Originally Posted by LTHatch

Nice review! Did you do any 1-3 gear pulls with it? Curious if its a noticeable improvement in the upper rpm range as it is in the low end passing range.

Doing some more pulls, it seems like I've mostly gained power in the low and mid-range areas. No real big difference on the high-end of the scale, though I suspect I may have lost some power up there.

In regular road driving conditions at 50 kph (30 mph) in 4th, the engine RPM dropped to about 1300 as compared to 1500 before. While highway cruising RPM at 100 kph (60 mph) in 4th has also dropped by about 200, from 3000 to 2800 approx.

Originally Posted by rabbito

i had simota carbon intake..i think its similar to the intake you installed above..lost low end and gained top end, small car like this shouldnt use low end..so i removed the carbon intake and changed to k&n drop in..
i have header, mid pipe installed

You mean "shouldnt loose low end" right?
I would say it really depends what you're using the car for. Regular everyday driving or racing.
For racing, I would say top end power would be more useful than low-end, and vice-versa for regular driving on the road.

Strange how you lost power with your intake. Extra air is usually good for an engine. I wonder if your exhaust might be the problem. If you don't mind me asking, which header are you using?
I using a Weapon R 4-2-1 exhaust header and a Tanabe Medalion Touring exhaust with the stock mid-pipe.

[tmontague]

There is no way that your rpm's dropped by 200. Gear ratios are a fixed thing that will not be changed regardless of air flow (unless wheel size or other is affected).

Your engine could very well be working less hard but the rpm's should be the same. Someone please correct me if i'm wrong

[NYC-SE]

You're right.

[invader166]

Originally Posted by tmontague

There is no way that your rpm's dropped by 200. Gear ratios are a fixed thing that will not be changed regardless of air flow (unless wheel size or other is affected).

Your engine could very well be working less hard but the rpm's should be the same. Someone please correct me if i'm wrong

Yes way! While the gear ratios are constant (like you said), it's been demonstrated that it is possible to drop the RPM at which the engine reaches it's torque peak!

For example, Tooter was able to do this with his intake manifold spacer design:

http://www.yarisworld.com/forums/showthread.php?t=49609

The intake valves on your engine open and close. They are abruptly starting and stopping the incoming air. Now the incoming air has inertia so starting and stopping creates pulses, or pressure waves that travel back and forth inside of the intake manifold runners. If the runners are made longer the pulses will resonate harmoniously at a lower frequency because they have a longer distance to travel to get to the other end. A lower harmonious frequency means reaching peak torque at a lower rpm. More torque at lower rpm means the engine pulls stronger without needing to rev higher.

[NYC-SE]

Originally Posted by invader166

it is possible to drop the RPM at which the engine reaches it's torque peak!

That is certainly true but that is not what your previous post stated.

In case there is any doubt this post was meant to be respectful, not trying to start anything.

[tmontague]

Lowering the torque on the power band is true. However lowering the rpm at the same speed w/ a different intake mani is not true.

you will be able to achieve a same speed in the same amount of time by shifting earlier in the Rev range with the improved manifold. Which can save you fuel. This is similar to low shifting w/ a stock Yaris to save fuel, except that you will get up to speed quicker than than stock.

But same speed to same speed with either intake mani will not change rpm's.

As stated above by NYC-SE i'm not stating this to flex my ego, it's simply me putting fourth my logic for others to poke holes at to better all of our knowledge.

[rabbito]

Originally Posted by LTHatch

Rabbito: Any idea why you lost low end with it?

i dont know but now i changed back to k&n drop in..lesser power in the top end but feel very zippy

Sent from my ASUS_Z00AD using Tapatalk

[invader166]

Originally Posted by tmontague

Lowering the torque on the power band is true. However lowering the rpm at the same speed w/ a different intake mani is not true.
.
.
.
As stated above by NYC-SE i'm not stating this to flex my ego, it's simply me putting fourth my logic for others to poke holes at to better all of our knowledge.

Neither of you guys are flexing any egos lol. I think I finally understand what's going on. In fact both you and NYC-SE's logic is very sound. However, and this is totally my fault for not mentioning it earlier, we're not comparing apples to apples.

Correct me if i'm wrong, but i'm guessing both of you drive manuals? It's true that engine RPM and speed are directly related to each other in a liniar fashion, but that relationship only applies in direct drive manual transmissions.

Unfortunatly, I drive an auto, which means the power produced by the engine is transfered to a fluid coupling before reaching the transmission. In this case the relationship between car speed and engine RPM is not liniar because that coupling is not transfering the full power produced by the engine directly to the gearbox.

By my logic, since I've noticed a drop in engine RPMs during my runs, the power required to drive my car at a certain speed (say 40 mph) has not changed (no weight removed or other mods made) and my gear ratios are still the same, then that must mean that the engine must be producing the same power required to drive my car at that 40 mph speed at a lower RPM. Right?
That, to me, means I've improved the torque output of the engine.

Does any of that make any sence? Or have I been drinking too much again?

[tmontague]

Hmm in that case I think you're correct. Every gear except OD (since that is direct drive) may see a lower rpm due to fluid losses as you stated.

It's not something i've heard about before but theoretically I can see how it's plausible especially if you are experiencing it in real world driving.

[WeeYari]

Interestingly I had similar RPM observations in 2008 with my automatic when I was working with prototype for PRM Jetstream intake. Couple of people called BS until someone offered up idea that torque converter came into play.

Originally Posted by WeeYari

After 90 kms (55 miles) driving, first impressions/observations:

Note: vehicle is a 2006 LB with automatic transmission

1. No CEL
2. Looks great
3. Excellent fitment
4. Pipe is cold to the touch at the throttle body
5. At my normal highway cruising speed, I'm turning 100-125 rpm lower??
6. Butt Dyno says:
   1. More torque off the line
   2. Somewhere between 4,500 and 5,000 rpm, the engine feels increased power gains

Unfortunately we've been dealing with heavy rains all day, and driving tests were not too vigourous. Also, while doing some WOT, I encountered a cop while doing 40km over the limit. Not pulled over, but spooked me out of further spirited driving.

http://www.yarisworld.com/forums/showthread.php?t=10721

[tmontague]

^which is very strange considering at highway speeds (constant throtle) you're in OD which is a direct drive gear with no fluid loss. This one is blowing my mind

[NYC-SE]

This still doesn't make sense to me. For one thing the Yaris auto has a lock up torque converter, so there should be no affect from that. Essentially there is a direct connection between engine, trans, and wheels when torque converter is locked up. (I may be wrong but I seem to remember reading somewhere that it locks up at 5MPH.?) No gear ratios have been changed, I don't see how engine can be turning at a lower RPM while wheels are turning at a constant MPH.

[invader166]

Originally Posted by NYC-SE

This still doesn't make sense to me. For one thing the Yaris auto has a lock up torque converter, so there should be no affect from that.

That's true, but isn't the torque converter lock-up function on the Yaris performed by an electrical solenoid on the transmission, that's being controlled by the ECU?

In fact, I found an article about how on some auto transmissions, it's actually possible to perform this torque converter lock-up yourself, at almost any RPM you want, overriding the ECU settings.

http://ecomodder.com/wiki/index.php/...nverter_Lockup

But now, what I'm trying to figure out is why this happened. Why did the ECU change the torque converter lock-up speed?