Santa Came early - R400 Roller Barrel Conversion!

[BruceBe]

You're going to need a different belt tensioner, before that air-box bolts up.

 

-Bruce

[BruceBe]

You guys are a riot. For starters, we all look like a bunch of clowns, idiots, and goofballs driving these cars around the track at 130mph+. can't get more comical than this.

 

But tadahhh! success last weekend. I managed to install the roller barrels on the engine, together as a pair (pfuuuii). Had to play a bit with the throttle cable and top end of the pedal (cable was too short.. i panicked for a few seconds) and still have to set the idle opening to precisely 6 mm using the shaft of a 6 mm drill bit and adjust the left and right throttle bodies to get the same opening using the black sets crew in between the bodies. I then tried to install the TPS sensor.. and attempted to figure out what direction to install it, with the electrical connection towards the engine or towards the filter. I think i figured it out .. the electrical connection should be pointing towards the filter ( I think and not like the picture I’m including here). It looks like it works the opposite way as it is on the R400 butterfly setup, in other words, starting at high voltage (4.62 V at idle) and with decreasing voltage as one opens the throttle. I will let you know if this works when I put a voltmeter to it.

 

Oh and by the way, i just sent my ECU to Caterham (Gatwick UK location) be reprogrammed for the throttle bodies and bigger injectors . I hope everything goes well. Wish me luck! I wrote my name on the ECU so please return to sender if you happen to see it in your new kits.

http://www.usa7s.net/vb/attachment.php?attachmentid=12139&stc=1

 

You want 4.6V at 6mm opening on the roller barrels. Use a 6mm drill-rod. This conversion reverses the sweep of the TPS. As a result, if you attempt to fire it up before flashing the ECU, it will immediately flood.

 

As a dealer, we have the ability to download and install new ECU calibrations, coordinating with the factory. Of course, we need your ECU.

 

Cheers,

-Bruce

[SK400]

Mike - no worries. That's the price we pay following you and learning your quick lines. We love you just like that, rough, inconsiderate and rock thrower. Don't change.

 

As for the incognito person who plans to surprise us with tons of HP... well bring it on!!! I can't wait. I just hope it's not Simon. I will have to work extra hard to keep up.

[SK400]

Bruce.

Thanks for your comments. Why do you say I will need a new bet tensioner? Is there something I should have done ahead of installing the roller barrels??

[BruceBe]

Bruce.

Thanks for your comments. Why do you say I will need a new bet tensioner? Is there something I should have done ahead of installing the roller barrels??

 

The upper mounting bolt/boss on the tensioner is going to interfere with the air-box, once you attempt to mount it. You need a belt tensioner for a CSR260/R500, which has that boss machined down and countersunk for a (shorter) socket-head bolt. Or, do it yourself.

 

-Bruce

[SK400]

Bruce

I think you are right.. the head of the bolt interferes with the carbon fiber airbox (see picture below). Interesting that they dd not provide the bolt you recommend in the roller barrel kit. I'll be reaching out to Caterham and see what they have to say.

 

On a different note, i took the bull by the horns and decided to cut my bonnet following a template provided by Caterham. Took a few times to get a usable template but got somewhere finally after multiple requests.. . I printed on a plotter, positioned it on the hood and went at it carefully with a Dremmel tool. Overall it worked pretty well. a bit of filling and sand paper and it looks pretty good. I will be covering the newly cut edge with a rubber trim and .. voila! it will look like a million $$, no damage to the hood at all, a clean cut. The hole is a bit larger, especially longer, compared to the sausage pipercross filter but to be expected. I think the template provided is designed to accommodate the full R500 carbon airbox, which takes a bit more room. Not a big deal, it still looks sharp and i wont have to re-cut in the future when i can get my hands on the full R500 carbon airbox (in backorder).

 

Still no news from the ECU i sent .. brrr. Let's see.

One step closer to 10-20 more HP and better sound!

 

See below (interference between bolt and carbon airbox)

 

http://www.usa7s.net/vb/attachment.php?attachmentid=12151&stc=1

 

Hood before cutting with printed template

http://www.usa7s.net/vb/attachment.php?attachmentid=12152&stc=1

 

Bonnet cut using dremmel tool

http://www.usa7s.net/vb/attachment.php?attachmentid=12153&stc=1

[BruceBe]

Bruce

I think you are right.. the head of the bolt interferes with the carbon fiber airbox (see picture below). Interesting that they dd not provide the bolt you recommend in the roller barrel kit. I'll be reaching out to Caterham and see what they have to say.

...

 

I don't think anyone manufacturers a headless bolt (it's called a stud) :-) And, the mounting boss breaks the air-box mounting plane. As mentioned, you need to either machine and counter-bore the existing tensioner upper mounting boss, or obtain a tensioner for a CSR260 or R500. With regards to putting the parts in a "kit", they have already been advised by us, that a modified (CSR260/R500) tensioner is required.

 

Cheers,

-Bruce

[SK400]

Yep.. so we need a modified tensioner Caterham number YD0159. It's currently out of stock, but I'll see if i can modify the tensioner i have myself. I don't think it should be that complicated, (hope i won't be putting my foot in my mouth soon).

 

Before I forget, Caterham did indeed receive my ECU and they were super helpful taking care of business. They've reflashed the ECU and should be on its way back to the US. Should be plug and play .. but let's see!

 

Next is the tensioner modification, install of the carbon airbox, adjustment of roller barrel openings & throttle cable setting and adjustment of the TPS sensor.

[Dave W]

A botton head bolt should help resolve the clearance issue. If you can not find one locally, try McMaster Carr. Dave W

[SK400]

Slowly making progress in the assembly. Last weekend, I spent some time adjusting the idle opening of the barrels to make sure that the right and left hand sides were set to 6 mm opening. I also got very lucky.. i snatched a rare R500 Carbon Airbox directly from Caterham which acts as a cover for the sausage filter and fills the opening i had cut in the bonnet beautifully. I'm really happy about this (looks great.. as good as factory). I hope to dyno the car this spring and try with and without the cover to understand the difference in performance. I also think that the cover will help me be "sound legal" at LimeRock, which is a good thing.

 

I'm not yet done with the belt tensioner modification. Looking for the right fastener (may have to look at McMaster Carr as suggested Dave) before modifying of course. That said, i think i can at least try to start the engine. I received my ECU reflsahed from Caterham. I will have to set my TPS sensor.. and then.. turn the key.

 

Suspense.. Will let you know.

[SK400]

Hooray! The engine started without hesitations ! I guess i got lucky. Here are my lessons learned on this step for those who will attempt this on your own:

1/ Setting the TPS sensor: after setting the throttle body openings to 6 mm using the shaft of a 6 mm drill bit and playing with the idle and throttle balance setscrews to get there, I rotated carefully the TPS sensor until the voltage read 4.62V on the nose. Please note that you should a) ensure that you have a fully charged battery (if not it will give you false readings) b) turn the car on (but not the engine of course), and use a multi-meter, inserting the probes into the back of the TPS connector and take the voltage between ground and middle sensor wire. Have the TPS sensor screws snug to allow rotation but not too much play. Once set, remove one TPS sensor screw at a time and add some blue loctite to the threads just in case and rescrew. Repeat for the other screw. When complete recheck the idle TPS voltage and ensure that it still reads 4.62V. -(still need to check TPS voltage when engine is running... wondering if it changes because input voltage may change a bit as the alternator helps the battery - actually this is a question for the pros, Bruce, others, any advice on this later point?)

 

2/ engine belt tensioner bolt clearance: I took my time but with the help of a large 9/16 drill, a dremmel tool, files and sand paper, i manage to counterbore nicely the casting and removed about 1/2 inch (a bit less) in length. I bought a new M8x1.25 bolt at the local hardware store with about 1/2" less in length than the original bolt.. et voila. It creates enough clearance for the carbon airbox the be installed.

 

See below the voltage of the TPS sensor at idle. Also a short video of the engine running. Idle RPMs were pretty low (500- 600 ROM ish) - but perhaps it is because the temperature was cold (32 degrees in the unheated garage). I may have to simply adjust the idle this spring after taking the car for a little ride and with the air filter etc installed.

 

Next step is to install the carbon airbox, air trumpets, filter etc. and see it completely assembled.

cheers to all

http://www.usa7s.net/vb/attachment.php?attachmentid=12201&stc=1

 

http://www.usa7s.net/vb/attachment.php?attachmentid=12202&stc=1

[yellowss7]

Congrats Seb. Guess that MIT engineering degree paid off after all. :jester:

[SK400]

LOL! I agree. I really wanted to go to Mars with that degree but obviously this did not pan out..... I guess it will be for another life. But not before I finally learn how to install a set of throttle bodies with no drama, in this life or next.

[yellowss7]

Add a couple of wings and a turbo and the way you fly around the track, you might just get liftoff! :driving:

[Nick OTeen]

When complete recheck the idle TPS voltage and ensure that it still reads 4.62V. -(still need to check TPS voltage when engine is running... wondering if it changes because input voltage may change a bit as the alternator helps the battery

It should definitely be checked again with the engine running. Assuming everything is healthy with the alternator, when the engine is running the alternator does not "help" the battery, it takes over for the battery as it provides the electricity needed and determines the operating voltage.

 

The battery's function is simply to store the energy needed to start the engine.

[BruceBe]

It should definitely be checked again with the engine running. Assuming everything is healthy with the alternator, when the engine is running the alternator does not "help" the battery, it takes over for the battery as it provides the electricity needed and determines the operating voltage.

 

The battery's function is simply to store the energy needed to start the engine.

 

Modern voltage regulators do a very good job of providing stable voltage for a range of input.

 

-Bruce

[Nick OTeen]

They do but they only work (at keeping the system operating voltage between 13.5 and 14.5 volts) when the engine is running.

[BruceBe]

They do but they only work (at keeping the system operating voltage between 13.5 and 14.5 volts) when the engine is running.

 

Right - but we're talking about a 5V regulator in this case.

 

Cheers,

-Bruce

[SK400]

Friends,

After a nice 2 days with family skiing in Vermont, I took a few hrs late Monday night to complete, mostly, the throttle assembly. I say mostly because there are still a few things to iron out including re(re)flashing the ECU. Here are a few tips for those attempting to install the kit.

1/ Installation of the Carbon Airbox and pressure sensor: when I installed the pressure sensor on the carbon airbox, I used a bit of RTV to ensure a good seal between the sensor and the surface of the airbox. There was a very thin opening between the airbox sensor hole and the back of the sensor body that needed to be sealed. What’s more, I layered a very thin layer of RTV on the front machined surface of the throttle bodies to ensure a good seal with the airbox and avoid any leaks. Lastly, I made sure that the carbon aribox air openings (the holes) did not obstruct, even partly, air flow when installing the box. I had to shave off a bit of the diameter with sand paper.

2/ TP sensor: I started the engine and with the alternator powering the system, recalibrated the TP sensor to 4.62V for an idle opening of 6 mm. There was indeed a small 0.05v or so difference when calibrating the TP sensor using the battery only versus when the engine was running. The voltage output went up with the alternator running.

3/ Tachometer: now that the engine was running (nice throaty sound ), I noticed that the tachometer did not move much as I was revving the engine up. It showed about a 4^th of what it should indicate. Discussing with Mark Rider from Caterham (very very helpful BTW), we realized that the ECU needed to be reflashed for separate coils configuration (need to pick up 4 pulses versus 1). So I ll have to send the ECU back to the UK. No biggie..

 

Here’s the finished product with and without the full race carbon cover. The opening is a bit big for the foam filter only but not as bad as I thought it would be. Looks awesome and perfectly matched for the Carbon Cover though. Quite happy with the finish and look. Can’t wait to drive the car this spring and “feel” the difference. Oh yes, still have to install the cat bypass which should help for sound as well.

 

http://www.usa7s.net/vb/attachment.php?attachmentid=12263&stc=1

http://www.usa7s.net/vb/attachment.php?attachmentid=12264&stc=1

http://www.usa7s.net/vb/attachment.php?attachmentid=12265&stc=1

http://www.usa7s.net/vb/attachment.php?attachmentid=12266&stc=1

[yellowss7]

Looks professionally done Seb. Nice work. Tom