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BOE Evora CAI

198K views 915 replies 124 participants last post by  jmardy 
#1 · (Edited)
Hints of better things to come for Evora and Evora S owners. BOE has produced me a great Cold Air Intake system for the Evora S and is modifing to the NA version of the car.

2.5% power and torque gains at 6450 rpm, gains start at 5600 and grow to Redline, no losses along curve, stable air flow ratios. System cuts weight out of tail and offers true cold air draw direct from body scope as per OEM and offers easier access and maintenance of filter element.

Quote from Phil at BOE:"Feeling very good about the car. It drives nice. Throttle response is very crisp and it's VERY eager to rev on tip in!"

Power plots
i) White curve - Komo-Tec Header, Komo-Tec 200 cell Cat, BOE Kold-fire custom tune
ii) Blue curve - (i) + BOE CAI
 

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#36 ·
I would advise you make direct contract with Phil at BOE Fabrication.

He posts on here as "turbophil"
 
#37 ·
Sorry for the delay...

We've been working quite literally around the clock since Julian picked his car up on another *very* interesting project and I've not been able to focus on this. We're having to travel the rest of the week but will be back on the CAI next week.

Cheers:up:

Phil
 
#40 ·
You know you can't post here any more without giving a least a small hint on what the other project is about ;) :)
 
#39 · (Edited)
+1 Excited about the CAI. What are the headers everyone is using? Are you talking intake or exhaust intakes?
The BOE CAI is an intake air system; header - cat combos used by a few members are Komo-Tec, 2bular and Supersprint, hp curves and info on each system are on various posts in LT including delta power curves by me and Bobby Racer.
 
#41 ·
+1 Excited about the CAI. What are the headers everyone is using? Are you talking intake or exhaust intakes?
The BOE CAI is an intake air system; header - cat combos used by a few members are Komo-Tec, 2ubular and Supersprint, hp curves and info on each system are on various posts in LT including delta power curves by me and Bobby Racer.
Thanks! Also, incase it wasn't clear what I was asking, I meant to say 'intake vs exhaust headers', I edited my post to clarify.

I gather the header mods are different than the exhaust swaps people are doing? Can you combine (for example) Komo-Tec or 2ubular headers with a Larini or Lotus Sport exhaust?

Here are the threads I found incase anyone else is interested:

http://www.lotustalk.com/forums/f17...-stage-1-means-plus-45hp-plus-20ft-lbs-98008/

http://www.lotustalk.com/forums/f170/2bular-na-evora-exhaust-system-117564/
 
#42 · (Edited)
I gather the header mods are different than the exhaust swaps people are doing? Can you combine (for example) Komo-Tec or 2ubular headers with a Larini or Lotus Sport exhaust?
The Komo-Tec and 2bular headers, downpipes, Cat sections are modular with OEM positioned flanges, thus you can mix and match and use any OEM or aftermarket silencer; a known exception is the new 2bular dual muffler/cat system, but this does bolt to back of downpipe.

Other things to watch on parts mixing is that Lotus changed flange orientation between downpipe and cat section on S cars and now has carried this on the ISP and all 2012 and beyond, so confirm with supplier, application to your year and model.

Here are the threads I found incase anyone else is interested:
A third link:

http://www.lotustalk.com/forums/f170/supersprint-exhaust-system-112843/
 
#43 ·
Latest mod, Tapeworks ColdGold warp; no specific temperature readings but surface is cooler to the touch that surrounding bare and black aluminum and plastic ducting.
 

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#44 ·
Let's not let this CAI solution go to waste!
 
#45 ·
I won't:eek:

We just got slammed, but the end is in sight!

Thank you for being persistant, it actually does help to keep the coals on the fire!!!:up:

Cheers,

Phil
 
#46 ·
Any NA volunteers; offer up your car to Phil to confirm application of the BOE CAI to it.
 
#50 ·
So, how's this working? We buy the CAI do a before an after dyno and report back? Is there any other data beside hp & tq we need to report back? Or, do we need to be in the vicinity of BOE?
 
#53 · (Edited)
Now to be fair, we need to get a comparison between the Radium CAI and the BOE product. My Radium is the most impressive CAI I have installed on any vehicle!
 
#55 · (Edited)
By all means by being fair, I mean
1. dyno
2. fuel trim data and ancillary numbers related to tune
3. Effects of idealized tunes on both CAI's.
I have read the other post which is great stuff so it seems like #3 is what we need to gather data on.
Have you put an annemometer (wind gauge) on that intake to see how much air is being driven into the engine bay? Temp difference would be interesting. I always thought that the stock MAF #'s on our motors tended to be quite rich, thus typically Toyota conservation.
Finally, forget SC cars here as I don't have one and that isn't the build that the original Radium was for though some people bought one and modded it. I have yet to see anyone post here about an engine detonation as a result of a Radium CAI or any other reason, for that matter. Think of it as a double blind study.

I have every intent of looking into a tune with you this year, but I'm a bit more pragmatic. As a comparison, I've DEFINITELY heard of some issues with the TVS SC'd cars (Eliges) v the MP62 cars. Among them is pushing more than ~265HP thru a 2ZZ tends to overload the stock trannies. That was an aside, but I learned long ago to compare and listen to both sides in the mods department. Everyone wants you to think their product is automatically better.

Am I correct to hear that the Radium CAI/ exhaust combo is producing a "LEAN" condition that has detonated motors? With or without headers? With or without a tune?
I applaud your work but feel there are a lot of unanswered questions here. I went thru a whole bunch of the CAI stuff years ago with my Cobra. In the fender, in the box, etc and I dealt with Jannetty Racing in Wtby CT who showed me all the dynos of all the combinations. GUy has a whole bunch of trophies and taught me about "HAPPY NUMBERS" on dynos. It was always a +/- a few HP, fuel trim etc. Headers were far more important on that motor than just about anything else. GUess I'm one of those "show me the money" types. Maybe the Radium guys would like to chime in as they did a lot of work also.
 
#56 ·
This is, in large part common sense.

The intake system from the factory, on ANY car, is not going to be that bad from a performance standpoint. The OEM is under fantastic pressure to generate the most power it can while creating the least amount of emissions possible that it can from an engine. Part of that recipe does NOT include a restrictive intake path. If you're seeing unreasonable power gains from an intake system on a modern car, then that system is doing something wrong--- even if "wrong" produces power on the dyno.

The lotus airbox is NOT that restrictive. It is however, big, heavy, hard to service, and complicated. A large reason for some of these factors is consistant with other OEMs in that they're trying to regulate intake sound, ie reduce it *substantially*.

Aftermarket intake designers tend to not care about sound, and that helps to reduce size, complexity, weight, and in many cases make service easier. Aftermarket designers do care about airflow, but so does the OEM! It's common to see a slight increase in power in the upper RPM registers with an aftermarket intake, but you should NOT see a huge gain. If you do, you know the designer of the inlet intentionally or UNintentionally manipulated the fuel and spark management with the intake.

In the case of your intake, I have shown the MAF values vs stock. Clear as day, measured air is more than 10% reduced. This means the ECU will provide LESS FUEL and MORE SPARK at a given RPM and throttle position than it did prior to the installation. It does this because it uses airflow and RPM as the primary drivers to determine load. Lower MAF values, like your intake provides at given RPM, equate to lower load in the ECU. Lower calculated load requires less fuel and more spark for a proper burn. Manipulating calculated load is NOT the correct way to make power.

I'm not making assumptions. It's right in the data. Your intake will data log more spark and atleast 2 points leaner AFR at WOT than the stock airbox on a stock tune in addition to 10+% less metered airflow... It makes sense what's happening, it just doesn't make sense to do it this way:eek:

As for motor failures, I don't have any numbers in front on me. Don't care to. I'm not trying to use a scare tactic to move parts. I just like things to be correct. Contact Lotus USA and inquire. I know they have a list. There have been several drivetrain claims denied once they learned of the installation of that inlet, because they understand exactly what I'm saying here. They've seen it first hand.

It is perfectly evident that the intake makes a mess out of the tune. It's been further discovered that simply rotating the offset KN filter impact trims and measured MAF values at various RPMs.

I posted about the problem with that intake quite a good while before Julian asked us to design a replacement. We actually hadn't planned on it, but he asked, the car was here, and we like fixing problems:up:. Fortunately, we have a dyno and several years of experience with tuning these cars on MAF, undestand Lotus ECU tuning pretty well, etc and came up with a decent part that retains an external air source, is easier to service, light weight, and most importantly does not make a mess of load calculations in the ECU...

Sorry for the long post. It's important to explain "the why" in all this. We've also worked very closely with our friends at VSA in california on identifying the issues here. Between the several Evora S and NAs that they have to work with and what we've done in our shop, I have an enormous database compiled of logs and many - many pulls on the dyno. The homework has largely been done...

-Phil
 
#57 ·
Ok! Can we do a tune for the Radium CAI with all the flow it allows, esp with a Larini exhaust or are you saying it is "Not tunable" due to a flawed design?
Another way of putting it is your CAI able to work stand alone or does it mandate a tune?

At this point I'd rather tune my Radium CAI rhan have to buy a new CAI and a tune as well.
 
#58 ·
At the risk of putting words in Phil's mouth and drawing too close a comparison to software engineering, I believe he is saying that an improperly designed intake renders the MAF nondeterministic, i.e. the same inputs (actual air flow) will give different outputs (measured air flow and therefore fuel/spark) over multiple runs. While nondeterminism can certainly be desirable in certain situations, this does not appear to be one.
 
#60 ·
This is exactly right. We've tried to tune the radium intake. One pass looks good, the next doesn't... Then we rotate the KN filter and a whole new set of data comes up:crazyeyes. MAF sensors are very sensitive to airflow....

So BRGelise, as far as I can tell, we cannot tune it. It's not that it flows too much air, it just doesn't allow the MAF sensor to meter correctly. Its ability to flow air is no greater or less than another...


-Phil
 
#62 ·
I would suggest you send him a PM or email through his company web site.
 
#63 ·
Hi Guys,

Hope to be producing these by the end of the month. Got crunched with race season and a project that's been brewing for a LONG time.... and it's probably the coolest thing to hit our little market since the Lotus Elise:)

More soon,

Phil
 
#65 · (Edited)
Secret Project: http://www.lotustalk.com/forums/f17...res-big-secret-132858/index4.html#post1954426. Not yet Evora ready!!!

As to the BOE CAI; still not posted on BOE Fabrication web site to click and order but it is mentioned under Evora S tuning.
BOE Fabrication - Lotus Elise, Exige, and Evora Performance ECM Tuning Products

Just an update; going back over treads, I realized I never posted the final dyno figures on my car. While the above link to BOE shows the power curves to an otherwise stock engine-exhaust, I also have the results inclusive of my headers, hi-flo 200 cell Cat & tune. The below comparison highlights the delta effects of the BOE Intake on my car already fitted with headers, cat and a tune.

Below 3500 rpm there is a +/- 1.8% power change as the power curves actually gets linearized up to 4500 rpm, from 3500 to 6000, +/- 0.4% but more gains under curve than losses, from 6000 to 6600 solid gains up to 2.8% i.e. 8.7 Hp gain to 324 at 6500 and 5.8 gain to 328 Hp at 6600. Power continues to trend upwards to the 7100-7200 rpm level and from my curve projections compared to Ramtins they all look to go past 333 Hp at redline, but I have no comparative data between mods here as we held to a 6600 redline for the 12 hours of dyno work. Fyi, the baseline (stock car) torque measured at 279 peaking at 4300 rpm and fell below 275 ft-lbs below 4200 rpm and above 5000 rpm. Final version with all mods gave peak torque of 292 ft-lbs and a range above 275 ft-lbs from 3250 to 6000. Even above 290 ft-lbs, is from 4200 to 5300. This is huge, a spread growing from a narrow 800 rpm to a wide 2750 rpm, this is drivability.

As a comparison of the effects of the header, cat & tune alone compared to the stock car: No regions of power or torque loss, power gains are 5% at 4500 7% at 5500, 11% at 6500 and 17.4% at 6650 – this is over 45 Hp and growing from 6600 rpm up, folks you feel this. Prior peak value of 294 Hp @ 6100 is now never seen again past 5300 rpm and now the curve only increases and never arcs down up to redline.

I have told a few people on LT that the header route is expensive ($6k in my case) and maybe not for all, but to start with a BOE tune & intake as most of the high end power increase comes from these cheaper mods. While true in comparing just peak power and torque gains, it is only telling half the story. Significant power gains in the 4000 to 5500 range seem to come from the use of short runner headers (i.e. Komo-tec & 2bular), where-as the long runner headers (Supersprint & PB Racing) seem to not break away from the base curves until above 5000 rpm. Both header versions combined with tune and intakes them seem to have converging power curves again from 6000 rpm up to redline. Regardless, the headers offer a beautiful symphony of sounds combined with the turbine like whine of the supercharger under full throttle.

Not sure if this really belongs here, about time to start a mods thread. Also please remember that dyno results are more qualitative than quantitative, thus my emphasis on percentage deltas, rather than absolute values. Results will vary from car to car, and dyno to dyno., as well as air temps, IAT’s, heat soak, etc. regardless of SAE correction factors. We tried to maintain consistency, but nothing is perfect including weather that ranged from the 10’s to the 40/50’s then 70's and humidity from dry to 90%. Your results may differ.
 
#67 ·
A nice write up Julian - the next step is Darton Sleeves (3.5L -> 3.7L), 97mm 9.0:1 pistons, stroker rods (3.7L -> 4.0L), custom cams, and a larger SC or twin turbos.


Re custom cams (possibly the crankshaft also - but would that need to be upgraded? lighter maybe? no idea here):

With all you have already done, next step should be a set of camshafts. Can’t really tell you how much the gain will be because I am not familiar with the rest of your upgrades but if we increase both inlet and exhaust cam duration by 20 degrees that will certainly free up the breathing at the top of the RPM range. Cost is £1600.

We calculate of 2GRFE cams for increased rpm over the standard unit, and the only thing that will stop your engine revving higher safely is connecting rods. We can supply a set of billet machined connecting rods that will fit your standard crankshaft and piston and allow 7800rpm safely. Cost is £1500.

Let me know if that is of interest.

Kind regards.
 
#68 · (Edited)
lol, not for me, this is the car I swore to myself that I would not mod. My TT RX-7 is feeling forsaken, on my workbench still ceramic exhaust manifolds, flow ported and ceramic coated intake manifolds, racing water pumps, new injectors, new turbos and in the shop new body panels, CF wings, diffusers, new trans, diff gear ratios, etal. and they sit and sit and sit with no time to put on..
 
#70 ·
I feel bored, with nothing for the Evora on my bench ready to install. This leads to a dangerous reaction where I just start ordering, 'cause. Ohlin 2-way coil-overs ???
 
#71 ·
I am still thinking a smaller supercharger pulley....even though the stock unit is a small as will fit without modification to the supercharger snout.....Check this link out....

Underdog Racing Development

I think that the supercharger is a varient of the unit on the evora and that these guys may be able to offer a solution here....just thinking....
 
#75 ·
I know everyone has thought of pulley size. But after initial inspection, many might be turned off by the fact that you might have to machine the snout of the supercharger and therefore determined it is not possible. Just pointing out that might not be accurate. As far as charge coolers go...it all boils down to temp and pressure of the air entering the motor. The temp is a delta added to the temp of the intake air, so if the intake air charge is cooler as a result of the CAI and cooler engine temp compartments then more boost can be added without additional charge cooling. Just thinking out loud....
 
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