Performance mods

[spunagain]

Hi Ramtin
Re last 2 sentences.

Did you mean
1) It's NOT only IPS. NA and S cars will have the exact same issues.
or
2) It's only IPS. NA and S cars will NOT have the exact same issues.

You have me worried now. If there are issues will a rolling road run with an emissions plot show it up? - Feel Free to PM me!

Regards
Spunagain

[dmpriso]

wolfman,

The Exhaust note will be quite a bit louder than stock with the KomoTec Kit. I really like it.
ECU Programming: You can order the self-programming kit from KomoTec and do it yourself. It's however quite expensive.

Komo-Tec OBD Flasher - KOMO-TEC Online

[lynnpreston]

Originally Posted by turbophil

On the IPS cars you must not change the intake. Stick with stock. There have been many failures due to the "CAI" intake systems and lotus will void the powe rtrain warranty if you run one.

On the other hand the tunes and exhaust do help all the evora cars including IPS.

Hope that helps,

Phil

Ok, I'll bite . . . please explain how the CAI is harmful to the IPS cars and not the manual cars. Not doubting, just very curious.

[turbophil]

I'm not really wanting to get into a big to-do about this, and perhaps it's been addressed in another thread already? I like the guys that make the part, I don't have, nor do I want to or intend to make a competing part. But the part is flawed and that flaw is a big issue to IPS cars and S cars particular, IMO (and Lotus’s).

The problem is that there was a general lack of understanding about MAF based systems when the part was designed. The strategy used broke a few fundamental rules that should be respected with a MAF based EMS.

1) The ID of the MAF tube was *changed* from OE specification. Any change in the ID of this portion of the intake (where the MAF is located) will have a significant impact on the calculated airflow. When the airflow is miscalculated, the calculated engine load becomes incorrect or different from what the ECU expects, and that can impact a whole host of things--- like the fuel and spark introduced to the motor.... and the shifting on an IPS car. We know that the ECU is miscalculating load in this particular application as a result to the intake.

2) There was no air straightener incorporated to the CAI intake system like there is on the stock system and the MAF sensor is in proximity to a curve. Without a straightener, airflow metering becomes unstable and will change erratically based on air speed in the tube. This lack of air straightener contributes to more of the problems as explained above.

3) The filter used is an offset design. We've seen firsthand in the data that the orientation of the filter will impact, greatly, the metered airflow which is certainly a problem working in concert with the lack of an air straightener.

After looking at a lot of data from cars with the CAI intake system, the power it "makes" is not primarily due to airflow or availability of air to the motor. Rather it's due to manipulating the measured airflow the EMS "sees" that results in a significant leaning of the AFR and greater spark timing due to “tricking” the ECU into miscalculating the load. Consequently, the IPS cars will tend to not shift correctly and possibly fail. As for manual trannys, the issue isn’t the tranny, but rather one car may run differently than the next, and “differently” is outside of what the Lotus or otherwise engine tuner had in mind. IMO, the S cars should tread very lightly when considering changing the intake as well since they’re more susceptible to engine failure from ECU load manipulation.

For those of us who have been around the lotus scene for a while, a similar learning curve took place on the 111 platform circa 2006ish… (Good-gawd, time flies, it's ~2013!!)

[Beophile]

turbophil,

Interesting read. Your comments reminded me of a thread I stumbled upon on another forum related to a cold air intake that is being developed by Torque Developments International (TDI) to allegedly be better than and address certain shortcomings of the Radium cold air intake.

It would appear that TDI came to a similar conclusion that the power gains are related to air flow metering. However, it would also appear that TDI came to the opposite conclusion regarding how the gains due to the air flow metering are achieved. That is, it is urged that the Radium cold air intake provides a more accurate metering than the stock setup and that providing an even more accurate metering would yield additional gains.

The thread at the forum I’m referring to is: Cold Air Intake PLUS from TDI - Engine & Ancilliaries/Gearbox - The Lotus Forums

In the above-linked thread it states that:

"Work has revealed that the standard Evora air intake system is even more 'orrible than those of us (us amateurs, that is) that have looked at it, appreciated. It is now better understood why the Radium CAI gives such a boost, and slightly better fuel efficiency, and explains why my earliest reports observed "cleaner sound" and "more relaxed" running at idling and low power. (Words to that effect - I've not looked back.) At mid and high powers of course other more dramatic effects take over! (And the work answers those who refused to believe such a simple change could be so beneficial.)

The airflow metering is carried out by sampling just a fraction of the flow at one side of the intake tube. (I've heard the figure of 5% stated.) The standard intake system disturbs the flow so that it is not evenly spread within the tube. Perfection would not be obtained by any system, but the CAI give less disruption and so the metering is more accurate - hence more efficient performance. More power, less fuel! That is in addition to the other benefits of less restriction, resonant length and colder air, of course."

[Plackslayer]

So Phil you are recommending the de-modding of the CAI yes?

[spunagain]

Hi Turbophil
Thanks for an interesting and somewhat worrying post!

Do you think there is a bolt on fix - perhaps a combination of a sleeve to correct the ID at the sensor and an additional air straightener (is that a collection of vanes before the sensor?)

I think you are suggesting the orientation of the pipe is critical - could I diagnose the risk of running lean on a dyno while monitoring the emissions at the tail pipe?

Cheers
Spunagain

[Allan Gibbs]

Subscribing to this thread.

[ramtin1000]

Plackslayer : I would do it as soon as posibble. You can PM me and i'll explain why you should

[alp]

Originally Posted by turbophil

2) There was no air straightener incorporated to the CAI intake system like there is on the stock system and the MAF sensor is in proximity to a curve. Without a straightener, airflow metering becomes unstable and will change erratically based on air speed in the tube. This lack of air straightener contributes to more of the problems as explained above.

Ha! I was just talking to ramtin about the screen prior to reading your post.

And adding to Beophile's obervation, BMW E46 M3 has a similar MAF setup. GruppeM offered their CAI system on the E46 M3 and what they did right was to reuse the OEM screen (straightener). Even then Ground Control released a different screen design called the GC Gizmo. Supposedly better. Wonder if that can integrated into the radium tube.

[Allan Gibbs]

On a side note, has anyone found any hp gains with a Larini exhaust? I've searched threads which usually relates to how good it sounds. I've found Sector 111's post dyno which has 252 hp. Thanks.

[ramtin1000]

If you mix that with the last cat delete then Yes there will be some HP gain. Just buy the larini unit that Sector has or 2bular's unit.

[wolfman101]

All this is looking a bit dreary for the chances of getting extra power from the S

So if a CAI is a no-go then I'd be looking at headers and a tune only?

[Allan Gibbs]

Also, how does the tune p, say the Kold-Fire work? If you buy one! Say the 290 in my case, is a new ECU sent to me? Or, do I need to ship my ECU?

[Julian73]

Originally Posted by Allan Gibbs

Also, how does the tune p, say the Kold-Fire work? If you buy one! Say the 290 in my case, is a new ECU sent to me? Or, do I need to ship my ECU?

The Kold-Fire/Komo-tec tune is loaded into your existing ECU while in your car.

[creaturekris]

Are you sure it was the CAI and not the fact that you turned a na car into a S? If you ran lean and blew up your car that is a tuning problem and not a part problem......these are the risks we take when we decide to modify our cars...... You could have had the problem with the hacked up Camry intake you put on your car and a factory sc kit if the tune was bad.
You can run rich all day long........ Only takes one lean spot in a tune to ruin your day though.....
Sorry about your car.

[ramtin1000]

Combination of headers, sport CAT, last CAT delete and Kold-Fire tune and unleash some serious power.

[Allan Gibbs]

Thanks. Is then headers, sport cat, and cat delete much louder than the stock exhaust?

[ramtin1000]

Here is what it will sound like:

400HP Supercharged Evora Drive By - YouTube

400HP Supercharged Evora Drive By - YouTube

[dmpriso]

Originally Posted by turbophil

After looking at a lot of data from cars with the CAI intake system, the power it "makes" is not primarily due to airflow or availability of air to the motor. Rather it's due to manipulating the measured airflow the EMS "sees" that results in a significant leaning of the AFR and greater spark timing due to “tricking” the ECU into miscalculating the load.

My personal impression is that this is the same with every aftermarket intake. I remember those discussions on the German Rx-8 board.
Would you also expect that the apparent power advantage will be, after some time, eliminated by the long term fuel trim of the ECU?