For everyone worried about their cams, why not just swap the stock intake cam back in until this is resolved?

 

Hollow cams don't help strength. That is strange. I wonder if the other cams that are snapping are intake cams as well?

Cosworth cams running strong. 40K on my car now.

 

Greg responded in the previous thread about broken cams.

I've been running the S2 cams for about a year now...spun them to 9k on nearly a daily basis. I currently have them out for a build and have inspected them...no cracking in the "questionable" area. I have a feeling that the problem either stems to mechanical failure or a batch issue. Have the affected parties compared notes (i.e. purchase date?)

 

It would be a great idea to create a thread inviting GSC, Cosworth and Kelford MIVEC cam users to post their milage and installation date. This way we will start to get a feel for the age/milage distribution of these parts out on the field.

 

Not necessarily. Have any stock cams broken?

In some cases a tubular shaft is stronger than a solid shaft (or at least as strong), for the same OD. One of the counterintuitive cases where less material means more strength. The only reason you don't see more of them is they are more expensive to produce.

I think in this case only the intake is breaking because that's the only one with the MIVEC mechanism adding considerable weight/inertia at the sprocket (easily doubling the weight), maybe exacerbating whatever harmonics are going on.

 

Is Kelford even a vendor on this site>?

 

I agree on something like this....

I bought mine back in aug/sept 08 but didn't get them installed and running until recently.. Broke with under 2k miles of easy driving

 

I have Kelford 272's installed since August of 2008, also bought them in the same month. I have just over 5,000 miles on them; but I'm making everything possible (contacting people and shops) to get them out of the car as soon as possible.

 

Our shop ***** with the FP4R's idles at 750 RPM smooth as glass even at leaner than factory AFR's. I have no idea why people claim to have issues with 'rough idle' on a 9. Even with VERY large cams there is enough MIVEC adjustment to reduce overlap to a point where there will be no lumpy lump. It takes ~ 60 deg of overlap to produce a slightly rough idle at 800-900 RPM. On an 8 you might end up with a slight lope at idle, but you can tune most of that out.

Keep your idle area timing in the same range as the factory, ~5 BTC and MIVEC between 0 and 10 and it shouldn't be rough at all, unless you are a tooth off on your cam install.

For S/D based ECU's make sure you are using enough MAP input signal filtering, large MAP input variations can cause large inj PW variations which can in turn cause a 'rough idle'. Some S/D ECU's even have a separate table for idle fuel which divorces the MAP input from the fuel calc so idle is improved in engines with low and inconsistent vacuum at low speeds.

 

Is Kelford going to be making a new version of their cams with a different core? I could've sworn they were on EvoM? I may try to email them to see if what they are going to be doing about this situation. I have a set sitting in my room right now, and if they're going to replace them with some sort of "improved" version, I might as well keep them. I'm sure that would please a lot of people as well.

 

Thank you finally the voice of reason. I was about to lose my mind since I have been suggesting this since these failures first appeared but this seems to have been consistently ignored in favor of "OMG my motor will blow up if I think about these cams".

Fact 1- Majority if failures were initially isolated to the greater DFW area which is a strong indication of a batch issue, not a design flaw. Your RPM/usage roughly mirrors my own so I am further confident in saying regardless of design characteristics the cams dont fail simply because the car is being pushed.

I am also curious about some other data that is being left out of the failures.

Point of purchase

Date of purchase

Installer

Motor oil used

Has the car ever had a turbo failure/metal failure of any kind?

What is the frequency of oil changes?

What does the oil look like after a change?

What timing belt is on the engine?

What MIVEC map is being used?

Etc.

 

I got in contact with them earlier in the week and they told me they were investigating the material side of things as well as the design feature aspect. So far they have responded to every email I have sent them, I would encourage you and any other Kelford customer to email them so that they feel the need to act fast in order to keep current customers happy or just down right keep some customers.

 

Just emailed them .

 

Good, keep us posted with the response you get!!!

 

I also emailed them. I will post up when I hear back from them.