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I have the Radium CAI now in the car = fantastic. The car drives easiser on throttle, fine till 3000 and then it gets loud. What a difference. I can recommend it to everybody=safe a lot of money against buying the "s". This is a real performance part powering up the normal Evora to a really fine sportscar.

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Lotus run the car rich for a reason. It doesn't run too rich. It is to add cooling at the flame front. Whether its the best way to cool is a moot point, but that is what it does. Overheating of the he

A stock V6S runs at WOT at redline an AFR of 10:1 on stock tune. A V6S with CAI, Larini headers, NO CATS, OEM backbox runs at WOT an AFR of 10.5:1 on stock tune.   Still seems pretty ri

Spent another day testing the intake at the track during the Lotus cup usa HPDE, zero issues with the intake, no CEL, no idle issues and the car felt fast again compared to the stock intake. I w

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I don't think any "outside video" is likely to give you what I assume you are seeking - a guide as to practical useability on British roads. Not unless you have a sound system that can authentically recreate real life sound levels, that is!

It may be helpful to restate that in "normal sedate" driving the sound is just standard. In "medium pretty quick" modes, the sound is different, as I have described above, but entirely acceptable. At high power and high revs it becomes LOUD. Realistically, that sort of use can only be made (on the road) in locations and circumstances and for periods where the sound is not likely to be a major issue anyway.

Having experienced the transformation given by the CAI, I find it hard to think of enjoying an NA without it. I believe that anyone who - for whatever reason - cannot envisage using one permanently, should avoid trying one out. It will ruin your future enjoyment of the standard car.

PS: All my comments relate to use with the Sports silencer. Radium used the Larini. It is quite possible that a better flowing exhaust is part of the improvement.

Edited by mdavies
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:huh: Are their dyno charts with the Larini fitted?

88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

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Yes, their website refers.

However the comparison between without and without the CAI remains valid as the Larini was fitted in both cases.

But it remains possible that a free flowing exhaust does contribute to the total effect that I and others have now experienced.

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I sympathise with your concern! Obviously people choose cars for a variety of reasons. For me the Evora is a sports car and my own spec - including basic Ardent Red - reflects just that. (You have previously commented on a mention by me of trying to minimise weight!)

So my perspective is that the driving experience comes ahead of everything else. And I don't have knowledge of fitting non-standard intakes to other cars - or of your preferences of course.

I have driven - track and road - Ferrari, Lamborghini, Porsche, Elise Sport 135 (don't laugh - can be quite noisy!), VXR8 and some others. I've already commented on the CAI loudness. Regarding the quality of the sound, my view is that it is "better" i.e. cleaner, crisper, more "sporty" at all powers and revs, and as I've said, imo it is in keeping with a serious sports car. Some people might say that at peak revs and power, it is just a little too loud. Purely a matter of opinion of course. I thought it marvellous but, as I've said, sensibly that sort of use must be managed with the same responsibility as the other aspects of a serious car.

After all it only costs the same as a few fills of petrol, and can be returned to standard - so............ but I've mentioned the risk!

PS: Again must repeat, my experience only with the Sports silencer

Edited by mdavies
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^ An article bringing together lots of info regarding the CAI from Radium :)

88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

For forum issues, please contact the Moderators. I will aim to respond to emails/PM's Mon-Fri 9-6 GMT. 

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  • 2 weeks later...

Yes, Toyota has TRD and Nissan has Nismo, Lotus will not sell "Motorspotrs" parts to the general public. Seems odd that a small company that had already done the R&D work and sells cars based on it's racing history will not help the owners who purchase their vehicles.

Yes it has baffled me that Lotus Motorsport has been cuffed from selling as aftermarket performance parts. You mention TRD and Nismo, additionally as an owner of three RX-7's I have belong to Mazda's Motorsport Deveopment team, now Mazdaspeed, for 15 years. They have been fantastic supporting the grassroots racing, offering performance parts from mild to LeMans series race engines and additioanlly OEM stock parts at heavy heavy discounts along with telephone/e-mail advice. They sell the parts as-is no warranty, but aren't hardass about voiding the cars orginal warranty.
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  • 4 weeks later...

I have posted some impressions of the CAI previously. Although positive, they were fairly guarded because the key aspect of the change in performance wasn't known. Particularly, I was aware that as - imo - subjectively the Evora is transformed to give a far superior driving experience in sound and feel, these factors could mask or accentuate the actual effect on performance.

Now knowing some measured results, I am happy to join with the reports made by others, and - for those who prefer brevity - to use the same word to describe the CAI: "Fantastic"!

For those who prefer more detail, my notes follow. Mel Davies


Comments on general characteristics and performance change

1 Introduction

These notes record and comment on the results observed from the fitting of a Radium Cold Air Intake (CAI), supplied October 2011, to a single Lotus Evora, 2010. (Close Ratio gearbox.)

The car had previously been fitted with the Lotus Sports silencer and this is taken as the “standard car” in these notes. (A free flowing exhaust may be significant in facilitating the improved engine airflow offered by the CAI.)

All the following comments are made in my non-professional opinion and on the basis of personal tests using only a manually operated stopwatch. Many comments are entirely subjective.

No dashboard warning lights arose on fitting and, after some 500 miles of running, no adverse effects have been discovered.

The car has been run exclusively on Shell Vpower fuel (97 octane).

The author has no connection with Radium other than having experienced the CAI.

2 General Impressions of CAI

The engine starts normally, firing slightly more immediately, if anything.

Idling is steady and unremarkable, from cold through to a fully hot engine.

The engine sound is much changed throughout the rpm and power ranges. It is quiet and entirely subdued at idle and in low power standard driving, but with a “cleaner” note. In mid-power use, it is somewhat louder than standard but, more significantly, has a deeper and more purposeful tone, comparable with other serious sports cars. This sound level is entirely acceptable for general use including, for instance, high speed cruising at medium throttle openings. At the highest engine power and speed, the sound becomes loud to a degree that would limit such use to appropriate (e.g.non-urban) circumstances. However it remains similar to comparable sports cars used at high power.

Higher torque is apparent throughout the rpm range.

The engine seems more relaxed in 5th and top gears down to about 1,100 rpm.

The distinction between Sport and non-Sport throttle response remains. The sharper Sport response becomes particularly noticeable in conjunction with the improved torque.

The car is entirely docile at low power whether the Sport setting is on or off. This docility is very noticeable in Sport mode when moving off and in low speed manoeuvring; the Sport mode is acceptable for all types of driving.

Unexpectedly, the CAI resulted in slightly improved fuel consumption. On a well-known route including town driving, general cruising and periods of full power and rpm, the dashboard typically shows 25/26 mpg as opposed to the previous 24/25 mpg. A small difference, but clearly apparent. This is possibly attributable in part to slightly less use of higher rpm as a result of the increased torque, although this is unnoticeable by the driver.

Overall regarding performance, apart from its improvement, the CAI seemingly gives quite the reverse characteristics to those usually found from “tuning up” an engine. Instead of making it more peaky and temperamental, it seems simply to remove constraints imposed by the standard intake; the engine seems more “relaxed”.

3 Comparative Performance

Before fitting the CAI, a performance baseline for the standard (Sports silencer) car was set to measure the acceleration time through a wide rpm range; this was chosen so as to assess the overall torque difference. Given that measurements were to be made using a manual stopwatch, the best accuracy was sought by staying in a single gear and using an in-gear rolling start. The engine was held at a steady 2,000 rpm until full throttle was applied and the time measured to the rpm when the first of the gear change-up lights came on.

The identical location was used for the standard and the CAI runs so details are irrelevant other than that Sport setting was on, the same amount of fuel and number of passengers were carried and both cases were measured in dry road conditions with negligible wind.

One difference noted was an air temperature of 19°C for the standard runs and 13°C for the CAI. A lower temperature would slightly boost engine performance, but would increase the aerodynamic drag. The relative strength of these factors is not known, nor is whether the engine controls apply any changes dependent on temperature.

Up to 6 runs were carried out in each case until a steady technique and reasonably consistent times were established. The highest and lowest timings were ignored. The three timings believed to be most representative are given.

4 Results

Standard: 11.4, 11.5, 11.5 seconds. CAI: 10.7, 10.6, 10.4 seconds.

Taking the smallest timing difference gives a reduction of 0.7 secs or 6%. Taking the largest difference gives a reduction of 1.1 secs or 9.5%.

With the CAI, obtaining timing accurately to the first change-up light appeared less precise. The high rpm acceleration was greater so that the interval from the first to the second and third lights was shorter; more accurate measurement would likely lie towards the lower end of the measured range.


5.1 The graphs of torque with and without the CAI published by Radium show that the test rpm range used was biased against showing the CAI to greatest advantage.

Measuring from the graphs the approximate percentage torque increases at 500 rpm intervals between 2,000 rpm and 7,000 rpm shows an overall average torque increase of 5.2%. However the average increase is only 2.75% from 2,000 to 3,000 rpm, but 6.1% from 3,500 to 7,000 rpm. At around 2,000 rpm there is zero or a negative gain. From 6,000 to 7,000 rpm the average increase is 8.8%. Thus it seems almost certain that had the test been conducted from an initial 3,000 rpm as opposed to 2,000 rpm, a greater percentage reduction in acceleration time would have been found.

5.2 Noting that the Radium measurements were with a Larini exhaust as opposed to a Lotus Sports exhaust, and were conducted on different vehicles (with potential differences in build versions, software, air temperature, fuel and perhaps other factors), the measured test results more than support the expected torque improvement. In fact, the measured improvement found as being in the range 6% - 9.5% is greater than that taken from the torque graphs.

5.3 Purely arithmetically, an estimate of the effect of bypassing the performance change below 3,000 rpm can be made by scaling the actually measured time percentage change by the ratio of the graphed average torque gain from 3,500 rpm to that of overall average torque gain. (6.1/5.2) This estimates the potential percentage gain had a 3,500 start rpm been used, and gives the range 7% to 11%. (As opposed to the 6% to 9.5% measured from 2,000 rpm.)

5.4 As an entirely subjective but strongly felt, additional comment, although the performance improvement measured more than supports the torque increase indicated by Radium’s graphs, the raw figures for performance gain in no way adequately convey the transforming improvement in the character and overall driving characteristics given by the CAI.

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  • 1 month later...

Rather intriguingly - for me anyway! - this thread has been viewed nearly 600 times since the last post, my notes on my impression of the CAI, yet no comments! Perhaps people are keeping a low profile re the CAI - understandable perhaps. In fact I suspect there have been many read-only visits from "outside" the forum, and indeed Googling the CAI topic does give this thread as one of the links.

However, thinking that they may be of interest to a few at least, I have posted below some further CAI related notes. Giving up old habits is tough and so I have written them in rather a formal style, but they are purely informal and arise from the same fun experience that I found the CAI induced in other ways. Also I emphasise that they cover just what I found - there is no major test programme behind them!

Cool Or What?

Notes on initial experiments on air flow and engine intake air temperature in relation to the Radium Cold Air Intake

1 Status of these Notes

These notes are produced as the outcome of a limited set of informal tests conducted for personal purposes, from personal motivation, without involvement of any other party. The author has no connection with Radium or Lotus.

No undertaking is given as to the accuracy of the measurements made or the conclusions drawn. Background and rationale leading to the exploration was drawn from personal experience, discussions and from information gleaned more widely. That background is not covered in these notes.

2 Introduction and Rationale

These notes describe some experiments and measurements made on a Lotus NA Evora fitted with the Radium Cold Air Intake (CAI). The tests are not comprehensive and have not been related to any made on a standard Evora.

The investigation was undertaken in relation to the following:

  • to explore to what extent the CAI as installed provides engine intake air that is cooler than that obtainable from within the engine bay;

  • to assess whether airflow and temperature factors might contribute to the additional 21.5bhp from the CAI claimed and measured by Radium - and consistent with some informal road tests of an installed CAI - noting that this increase has been considered to be distinctly larger than that found to be given by other such tuned air intakes;

  • to assess whether the standard Evora bodywork air inlet grill provided an effective and adequate air flow for the CAI, noting that the Evora GTE is provided with additional “scoops” fitted over the bodywork grills and that racing versions of the Evora have additional slits and inlets cut into the bodywork;

  • the author’s understanding that other investigations relating to the power output of the NA Evora have indicated that the temperature of the engine intake air has a bearing and that the airflow arrangements of the standard car may not provide the optimum intake temperature.

3 Temperature Measurement Technique

Temperature was measured via a thermistor mounted in a small protective structure that could be suspended or positioned as wished. This was wired in series with a battery and sensitive meter located in the passenger area. Thermistor self-generated heat and thermal lag were made negligible by dissipating less than 5mW and allowing air flow to reach the thermistor via a light plastic mesh protruding from the rest of its mounting structure. Prior to use, the arrangement was calibrated for the range 5 deg C to 50 deg C against a standard thermometer sensitive to 1 degree C. In use the arrangement proved sensitive to temperature changes of 1-2 deg C in the range of interest.

For one test an Evora GTE type bodywork air scoop was added, fitting closely and sealed around the air inlet grill aperture in the bodywork. The scoop was moulded from plastic sheet and followed the GTE shape as observed from a number of photographs.

4 Scope of Experiments

Only “road type” speeds and engine use were explored, and only within the limited ambient range stated. The measurements do not form a comprehensive set but were aimed at exploring specific questions.

Temperature measurements were made in the engine bay and in two positions near the CAI air filter behind the CAI screening panel.

Measurements were recorded over a number of days with different external ambient air temperatures. Various road speeds were used as seemed appropriate. The air inlet grill in the bodywork was left as standard except for the specific testing of a GTE type scoop and the testing of the effect of blocking off the grill. Only the single grill on the engine air intake side of the car was modified in these cases.

5 Summary of Measurements

5.1 Temperature in engine bay Ambient: 7.5 C

The engine bay temperature was sensed approximately midway both between the end of the engine block and the Radium screen panel and between the top and bottom of the bay.

The intention was to find the temperature impact on the engine side of the Radium screen panel and an indication of how this varied with power and speed, airflow in the bay presumably also varying with speed.

At medium cruising speeds the temperature settled around 27 C. With more power and speed - and presumably, airflow - the temperature rose to to 35 C.

After stopping (engine off), over two minutes the temperature climbed to 50 C and continued to rise. When motion was resumed the temperature slowly reduced.

5.2 Effectiveness of bodywork air inlet grill

The sensor was positioned above and towards the rear of the CAI filter element (behind the CAI screen panel).

The intention was to obtain temperature indications of how the inlet airflow would be affected by modifications to the bodywork aperture.

5.2.1 a) Air inlet grill as standard Ambient: 7 C

At a range of speeds and power, temperature remained in the range 13 C to 14 C.

After stopping (engine off), the temperature reached 19 C after 3 minutes and 27 C after 8 minutes.

b) Repeat Ambient: 11C

At medium speed and power, temperature remained in the range 14 C to 15 C.

5.2.2 GTE type scoop mounted on inlet grill Ambient: 7C

At a range of speeds and power, temperature remained in the range 13 C to 14 C.

5.2.3 Blocked air inlet grill Ambient: 10 C.

The inlet grill was blocked. (The scoop remained in place, though irrelevant.) This test was limited in duration because of potential effects on the engine bay temperature.

At only medium speed and power the temp rose to 23 C, and apparently stabilised.

When the grill (with scoop) was opened, at medium speed the temperature rapidly dropped to 14 C.

5.3 Air feed to CAI filter element Ambient: 10 C

The sensor was positioned just in front of the CAI filter element facing the airflow from the bodywork intake grill.

At a range of speeds and power, temperature remained in the range 11 C to 12 C.

When stopped (engine off) the temperature rose to 24 C in 8 minutes.

Repeat Ambient: 6C

At a range of speeds and power, temperature remained in the range 9 C to 10 C.

When stopped (engine off) the temperature rose to 17 C in 4 minutes.

6 Discussion of Measurements

Although measurements apply directly only to the ambient temperatures used, most suggest implications for other ambient temperatures.

The measurements indicated the following.

  • The temperature of the engine bay adjacent to the CAI runs much above ambient and thus heats the engine side of the screening panel. The thermal characteristics of the panel and its size are thus relevant.

  • The CAI screening panel does effectively reduce the temperature surrounding the CAI filter from that of the adjacent part of the engine bay.

  • With the car stationary, and thus no forced air flow, engine heat is rapidly transferred to the CAI filter intake region behind the screening panel.

  • Blocking the bodywork air inlet grill raised the air temperature in the region of the CAI filter intake towards the temperature of the engine bay, albeit slightly lower, but this test was then terminated.

  • The air temperature in the region of the CAI filter was consistently at a clearly higher temperature than ambient, measuring 9 to 15 degrees C for ambients from 6 to 11 degrees C.

  • The air temperature at the front of the CAI filter, its nearest point to the inflow from the bodywork grill, ran at a slightly higher temperature than ambient, measured at 2 to 3 degrees C higher than ambients of 6 and 10 degrees C.

  • The GTE type scoop had no measurable effect on the air temperature in the region of the CAI filter.

7 Conclusions

These conclusions focus on the operation of the CAI as installed in the Evora rather than more general Evora airflow considerations. Some conclusions draw on background information that is not included in these notes.

a) The CAI does indeed provide engine intake air at a colder temperature than that of the engine bay. The CAI screen panel is an important component of the CAI.

b) The standard bodywork air inlet grill does provide for the CAI to access air at only a few degrees C above ambient.

c) A significant part, unlikely to be less than 25%, of the additional power provided by the CAI derives from its provision of colder air to the engine.

d) Rather unexpectedly, the air temperature around the CAI is unchanged by fitting a GTE type scoop to the bodywork grill. This was not explored in more detail, such as in front of the filter or the possible effects in the engine bay.

8 Further Thoughts

Additional ducting would probably enable close to ambient temperature air to reach the CAI filter, but such ducting would possibly compromise the air flow to the general volume of the engine bay. It is noted that the air temperature towards the rear of the CAI filter was measurably higher than that just in front of the filter and that on the engine bay side of the CAI screen it is much higher. Significant temperature gradients thus exist and obstructing the general airflow to the engine is likely to be unwise. For this reason, it is not intended to consider extending the size or fit of the CAI screen which, as provided, allows clear space for air to bypass it. Increasing the reflectivity of the screen on the engine side might give some reduction in the engine heat transferred to the CAI filter area however.

Edited by mdavies
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May i reply to all those words in an easy comparison: it is like watching TV on a normal screen and then see the same thing in HD.

So, it is not a big thing; but if you get used to HD TV watching, then... you realise the difference and you won't quit it.

What I do not see at mine: fuelconsumption is the same; its even lower when cruising around at below 2000 RPM. What is a bit nerving, is the real loud suction noise; but this is really the only thing mentionable on the neutral (not negative) side. I love the CAI of Radium and I don't care about measuring, data, %age etc. I want fun... and I have it.

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I think part of the reason that people aren't jumping at this kit is for 2 reasons. Air intake noise increase, not everybody wants there car to sound throaty. I already have the sports exhaust option and find that it is about as loud as I would want for motorway driving. Add in more induction noise and it would end up like my Exige which was great when you were in the mood and PITA the rest of the time. Second is the warrenty issue, espescailly with 3 years warrenty. Once cars start hitting 3 years old then there might be a bigger demand for an induction kit.

Don't get me wrong it looks an extremely well made kit for me I would rather wait and see if Lotus come up with something which won't effect my warrenty.

Edited by Mikie711
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Second is the warrenty issue, especially with 3 years warrenty. Once cars start hitting 3 years old then there might be a bigger demand for an induction kit.

Don't get me wrong it looks an extremely well made kit for me I would rather wait and see if Lotus come up with something which won't effect my warrenty.

Mikie, yes the warranty question is still open. On the Evora chat thread I have posted that it will be very interesting to compare the Lotus engine upgrade kit just announced (new intake, Sports exhaust and decat) with the CAI plus Sports exhaust. I'm speculating the intake might be very similar technically. (Speculating - I know nothing.) Only the exhaust is illustrated in the brochure. I wonder whether the intake might not quite be finalised? And that Silverstone car?

From a quick scan of the Lotus Brochure, the small print applying to the whole range of kits states generally they are for track use only, but does leave the way open for more detailed definition by referring to "some aspects of warranty" and needing to refer for details. We'll have to wait and see. I do trust that the engine upgrade will be available without the Sports silencer for those (like us) that have them already! At least it is good that the cost of the CAI is relatively low so that changing to the Lotus intake would be no great sacrifice.

Re engine sound levels, each to their own and we all have our own levels of deafness, but I wonder if the CAI intake suction noise is mostly apparent to those with standard silencers - I was not particularly aware of it with the Sports silencer. Also, motorway cruising - autobans excluded! - uses only say 30% of engine power and low/medium revs. I did try a motorway run and found the engine sound quite acceptable in that mode. Certainly noise builds as the foot goes down. I am trying to pitch my comments at "Evora driver preferences" - no such single thing of course, but people that want to travel in refined calm are unlikely to be in an Evora - are they?

Ritchie, I like your HD TV comparison! Once experienced the ordinary version becomes ........ well ....... it's all right, I suppose..... but!

I'm not surprised you see poorer fuel consumption at 2,000 rpm and below. The torque graphs from Radium show the CAI does not perform down there. Some of my previous many words about it did comment on that, although I found the engine ran perfectly smoothly at low revs.

Re the induction suction noise, as above I wonder what silencer you have?

Edited by mdavies
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On the Evora chat thread I have posted that it will be very interesting to compare the Lotus engine upgrade kit just announced (new intake, Sports exhaust and decat) with the CAI plus Sports exhaust. I'm speculating the intake might be very similar technically. (Speculating - I know nothing.) Only the exhaust is illustrated in the brochure. I wonder whether the intake might not quite be finalised? And that Silverstone car?

What makes you think it's a new intake? It's simply a performance air filter. Also the decat pipe Lotus offered in the kit is a 'S' part only due to the fact the N/A uses a different downpipe, so the fitment is not a direct swap. I believe Larini do a decat pipe for the N/A though. However, a reflash of the ECU would be required.

Did you manage to do a rolling road comparison on the Radium CAI? I've only seen their findings, nothing independant.

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What makes you think it's a new intake? It's simply a performance air filter.


Did you manage to do a rolling road comparison on the Radium CAI? I've only seen their findings, nothing independant.

Jaws, if you actually know that, I'm really disappointed. I have just speculated, as I said, but surely there are some straws in the wind?

Apart from the statement of "improved performance", there is £2,950! For a filter and exhaust only - really? [Edit, correction on that, it includes the baffled sump. Even so.] And my dealer told me there was insignificant performance gain from the Sports exhaust when I got mine. Then there is the Silverstone car, up to 300 bhp, so surely Lotus must match that at least, and does that just come from a thinner filter? Then the Radium CAI, also up to around 300 bhp with its extra 21.5 plus whatever a better exhaust itself does give. (And as I've said before, the whole may well be greater than the sum of the parts.) Lastly, I have been told of links between some of the (UK) interested parties working on the subject.

None of which adds up to any actual knowledge! I said it will be interesting to find out - but I can't see Lotus coming up with something that doesn't at least match Radium and Silverstone. And if they have just a performance filter that can do it alone - K&N watch out! But of course if you actually have the facts - please tell.

Re the Radium CAI, no, no rolling road, just my road test that did support the percentage gain that Radium claim. I have given quite a detailed report a few posts above. (28th Nov I think.)

Edited by mdavies
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Jaws, now it seems our uncertainty won't be resolved any time soon. Repeating part of my post on the Evora chat thread, a post in another place quotes a fairly good source as "The flyer was an early release of products they envisage to supply". More detail at the other place.

That ties in with a casual mention made to me recently that the engine performance aspect was still being worked on.

So it's back to how Silverstone get their 300 bhp and whether the CAI can be pushed up from its (Radium graphed) 298 bhp. Have to see if more testing with the air scoop might be possible!

Edited by mdavies
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Wow just been reading up on this. Sounds great, and performance increase to. I think this will be on my list of things to check out.

.:: Lotus Evora 400 - Red ::.. | ..:: Tesla Model S - Midnight Silver | Renault Twizy - Brilliant Black ::..

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mdavies, dont suppose you can remember how much this cost you including shipping and how long it took to arrive?



.:: Lotus Evora 400 - Red ::.. | ..:: Tesla Model S - Midnight Silver | Renault Twizy - Brilliant Black ::..

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Dale, what is it politicians say? "I don't necessarily accept the premise of your question, however, if I may answer in my own way."!

On the Radium site I see the price is now $430. That translates to £280 or so at today's rate.


They launched the first batch at a little less, but that sold out. I am aware of a kit that was supplied in about 3 days, costing about £35 shipping. (Trackable at each step.)

The installation instructions, with lots of photos, can be downloaded from their site via a link near the bottom of this page:


As I said in a previous post, an important tip, not in the instructions, is to fill up the engine bay under the work area with a blanket or whatever, to catch anything that slips from the fingers. I can imagine that removing the undertray to retrieve might be annoying!

The step where the instructions say: "Carefully remove the air filter box housing and tube assembly from the engine bay." has been found to be easy in principle but does require a couple of plastic ties to be cut and as the whole thing is very bulky, can be made easier by removing it in two pieces. There are two air intake tubes and the lower one enters via a rectangular tube - see in the instructions photo - into the bottom of the main airbox. It is held in by two small screws that can be removed and then the top box taken out first to give access to the lower tubing to cut the ties down there. This sounds much more difficult than it is when the parts are visible when doing it, I understand.

Also, as in the next photo, when putting in the M4 bolts to hold the MAF sensor in place, ensure they are tightened fully. When the intake has been fully installed there might not be much clearance to re-tighten. By no means impossible, but could need the short end of the Allen key to be ground down to shorten it. Best avoided.

It is my understanding, from several sources, that whilst there are no serious problems, a certain amount of compressing and wriggling of the standard resonator box flexible parts is necessary to separate them. (3rd and 4th photo.) And perhaps the Radium suggestion of one hour for the whole job might be a little optimistic!


Edited by mdavies
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Cheers for the answer "in your own way" :)

It wasnt a loaded question, just trying to understand if any hidden costs existed, such as import tax etc.

Good to know it came so quickly though.

.:: Lotus Evora 400 - Red ::.. | ..:: Tesla Model S - Midnight Silver | Renault Twizy - Brilliant Black ::..

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