2bular NA Evora Exhaust System

[Julian73]

Personally I think the K&N's are a pain in the ass to clean and reuse. Nice to know that a clean OEM paper filter is just as good.

I am surprised that the extra weight and complexity of the two-path muffler buys nothing but a better sound; that means so much restriction up stream that nothing left to gain. Wish I had the 2ublar downpipe in place to remove one more more variable between our systems, but with what I got, I believe your 5% gain from hardware beat my gains if the tune was backed out. I believe this is the most expensive Hp I have ever purchased. When I get the old parts back home to the same scale I can see how many ounces I saved.

[Julian73]

Don thank you for the support, you gave me moral support and indirectly through your prior install at VSA we had them on the phone a few times to discuss hardware idiosyncrasies.

Originally Posted by Allan Gibbs

... On a side note, I've heard that TDI is coming out with a CAI or a TDI filter option that attaches to the Radium. ..

I have been reading this on the other forum. I have turned gun shy on the CAI and don't think 3, 7 or 14 Hp is worth the trouble and risks. I see the Radium AFR curves all over the place, wouldn't be so bad if it was static and could be tuned out, but I understand it is dynamic due to vortex shedding. If TDI steadies the flow, that would be great, but as I say with the risks I would not install a CAI without dyno testing and tuning so a few hundred dollar upgrade can go well over a thousand.

Kold-fire tunes are de-riching these cars quite a bit, and I suspect that Lotus is using the super rich settings to cool the intact charge, in lieu of an intercooler; I have no margin to have a fluctuating AFR go lean.

[turbophil]

Thought I'd chime in...

The tune certainly made the most dyno difference on a repeatable basis. I think it's possible there's power to be had in longer headers, aftermarket DP, and eliminating the cat.

I didn't measure pre-rotor vacuum, but I'm pretty sure there's power to be found upstream of the throttle body, but would need the proper design to utlize the MAF correctly... if I had more time with the car, I could make this with the correct compoents and design...

One thing that cannot be ignored is the sound. The new headers and cat sound fantastic. I hear a lot of nice exhaust notes and short of ultra high-end italians with flat cranks, this car sounds on par with about anything out there. It's restrained but very bold at the same time. It's really quite impressive. Perhaps the exhaust didn't make much in the way of power, but it really will improve the ownership experience, IMO. There's also the benefit of much less exhaust heat in an engine compartment that really needs all the help it can get in heat mgmt...Julian brought us the parts, so no dog in the hunt on the exhaust parts. After hearing Julian's car, if it were my car, I'd dump the stock echaust upstream of the muffler as well-- regardless of power gain.

2 more pennies...

Phil

[Julian73]

I will add to Phil's excellent comments that the power gain looks usable. It is smooth and has increased torque from off idle to redline, no dips and peaks. A full curve is better than a power peak any day. I don’t fly up to get my car till Friday so I must take his word on the sounds, the video doesn’t do it justice. I would do the switch again; I just cannot stand looking at those Camry exhaust manifolds.

[invictusmaneo]

looks good, at least consistent.

Phil have you had luck on the 290 tune leaning out the factory AFR reliably?

It seems as if messing with the factory MAF/MAF tube can throw it all off.


Either way-the new headers certainly do look much better than the OEM junk

[Fast_XC]

I have to ask how come the dyno plots don't go to 7200 RPM which is the red line in sport mode? It seems that after the mods that the car could have pulled more RPM than the 6600 shown.

[Julian73]

Originally Posted by Fast_XC

I have to ask how come the dyno plots don't go to 7200 RPM which is the red line in sport mode? It seems that after the mods that the car could have pulled more RPM than the 6600 shown.

Note my statement of parameters, those curves are with sport mode OFF.

[turbophil]

In the case of a 2 wheel dyno like ours, the ABS and Vehicle stability systems trigger a fault, thus disabling Sport mode. This situation cures itself after a short drive. Peak hp numbers would be higher even though torque is falling off a cliff if we revved the motor higher in both stock and modified configurations, but there's not much point in revving the motor just for the sake of revving it...

Cheers,

Phil

[shay2nak]

Was there a change in the AFR between the stock and K&N filters?

[turbophil]

Originally Posted by shay2nak

Was there a change in the AFR between the stock and K&N filters?

None

[Bobsy Racer]

Originally Posted by turbophil

In the case of a 2 wheel dyno like ours, the ABS and Vehicle stability systems trigger a fault, thus disabling Sport mode. This situation cures itself after a short drive. Peak hp numbers would be higher even though torque is falling off a cliff if we revved the motor higher in both stock and modified configurations, but there's not much point in revving the motor just for the sake of revving it...

Cheers,

Phil

Phil,

When we did the Dyno work on my NA Evora, before and after my 2bular Header-Downpipe-Metallic Cat installation, we were able to use the Sport Mode on a 2 wheel dyno. We did some sequence of hitting the Sport Mode button, and the Traction Control button multiple times, and then it worked fine, and revved to 7,100 RPM. (See my Dyno sheets in post # 31 of this thread.)

Looking at Julian's Dyno results, it looks like I definitely need to add your ECU tune to my installation !

[Julian73]

Time to look at the BOE CAI setup.

BOE Evora CAI