Are any of the failed cams kelford 280s? Is anyone even using these? I'm really close to install with my "D" cams...not interested in being a guinea pig though...

 

So I have these M3s sitting here brand new wrapped up. They have been there for the last couple days. Just for giggles I decided to open them up and look at the mivec cam. There are pics of newly purchased Cosworths..

 

ok, here are some pictures i took today to compare a few different cams. these were just cams i had sitting around at the time today.

first up is the GSC S2 cam from TNT's car. pictures have been posted of this one in a different thread, but i compared this one side by side with a brand new kelford 272intake cam. you can see the mivec groove is identical. the cams overall are identical, and there shouldn't be any question that these are the same core.



(close up of the kelford groove)

(close up of the GSC groove)



next, i took pictures of the FP4R cam that we were replacing the GSC cam with. you can see the cores are definately different. the mivec groove is much more shallow in the FP cam vs the kelford and the GSC. denver measured both the grooves and he will post up the difference.
(close up of the FP groove)

(FP vs kelford)



(kelford core vs fp core)


i also took pictures to show that the bolt for the gear doesn't even go that deep into the cam, so the cam bolt shouldn't be the issue (although if the bolt were a bunch longer it could add a bunch of strength to the cam)



edit** it should be noted that i am not advertising for FP. i actually run kelford cams in my own car, and liked them so much i've decided to sell them just 2 weeks ago. but now i can't sell them until i find a solution has been implemented by kelford for the mivec intake cam. for evo8's i would still recommend them

 

Wow pretty big difference. The fp's look way beefier than the kelfords.

 

sheeesh, no wonder they broke

large section change at high load area

insufficient inside radius

almost looks like some cut galling in the bottom of the groove, so cut not ground?

hindsite is 20/20 and feel for these cam manufactures having problems, you know everyone in this biz has their heart in it

bet that Mivec would get enough oil with even less groove depth than the FP4R

would be interesting to see the factory cams, to see how they approached this area

 

cosworth asked me for pictures so they could forward them to their engineering department.

 

Those FP cams look really good. You can easlier tell FP uses a different core from the other companies. Also the mivec groove is much shallower.

 

I have a set of S1 in my garage that Kevin swapped out for the S2s. After seeing the pics Kevin posted I dug them up and looked at the grooves. The grooves look very similar to the FP cams. As for the S2s installed I need to get with Kevin and get them looked at pronto. (hint hint)

 

Somebody want to post pics of a set of stocker set, area in question. Maybe i missed them if they were earlier but toss them up please. I guess I could go over to Dave's and see his.
-James

 

Wow this sucks pretty bad, It happened to my buddy running some S2's as well(snapped in half), when he told me about it I was very surprised and now I'm worried because I have some S2's as well....hope this is just a defective batch issue, but I don't think i wanna take that chance....maybe time for a FP5R intake cam.

 

i should have a stock intake cam sitting around somewhere too. i'll take a look and if i do post some pictures of it.

 

Wow, that sucks big time.

-Don

 

May want to take of the VC and take a look, may find something else. something has to create a lot of torque to break that cam, could have been during install, could be you dropped a rocker and bound it up... you didnt mention what you were doing when it broke?
And yepp might as well start taking that head off...everything is going to have to be replaced in the valve train.

 

Did you look at the pics? I think it's safe to say there is CLEARLY a manufacturing defect with these cams, and can rule out installation error.

 

I think at this point the vendors with the cams breaking should do x-ray analysis of the cams in stock. They shouldn't have to x-ray every cam from every batch, but maybe a random 10% - 25% from every batch. The manufacturer of the blanks should also do this, and also make this a policy going forward. Obviously costs will go up (assuming that they don't do this already), but it will save your engine. I'm not a quality control engineer but this is generally how QC is done in manufacturing. I'm wondering if cryogenically freezing the cams would help enough to prevent breakage.