my intake cam snapped?!!?
First one broke on my letting off the gas on the dyno. First one bent ten valves and guides. Second one broke on a dyno run going into boost at 4000. Didn't even bend a valve but I already had the head off before I saw that.
Kelford 272 Mivec cams.
Have Cosworth M3's in it now. Will probably break too. We got two spare IX heads now cause next time the current head might not be fixable. Wanted to use JUN cams but can't seem to get a set in a timely manner.
The machineshop that did this head. I showed the old guy the first broken cam and he said he has seen some Honda cams do that. The crossdrilling for the Mivec Oiling is the culprit. Just not enough metal left for such a small journal to have any strength.
I first contacted Kelford and they told me to figure out what I was doing wrong so it wouldn't happen again. Second time we had new Mivec, new factory bolt, belt, tensioner. Its nothing I did, its the cam. Never posted up before. Glad someone else did. Its too bad a lot more people will be having this problem and the repair bill is not always cheap.
Kelford 272 Mivec cams.
Have Cosworth M3's in it now. Will probably break too. We got two spare IX heads now cause next time the current head might not be fixable. Wanted to use JUN cams but can't seem to get a set in a timely manner.
The machineshop that did this head. I showed the old guy the first broken cam and he said he has seen some Honda cams do that. The crossdrilling for the Mivec Oiling is the culprit. Just not enough metal left for such a small journal to have any strength.
I first contacted Kelford and they told me to figure out what I was doing wrong so it wouldn't happen again. Second time we had new Mivec, new factory bolt, belt, tensioner. Its nothing I did, its the cam. Never posted up before. Glad someone else did. Its too bad a lot more people will be having this problem and the repair bill is not always cheap.
Last edited by Early EVO; Mar 11, 2009 at 12:15 PM. Reason: added
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A friend of mine experienced this same issue.. I'll try to have him chime in on the details. From what I remember, he had Cosi's as well, not sure if it were the M2s or M3s, but he has since switched to HKS and has been happy ever since.
one cam that i can say is built correctly is the fp cams(made by comp cams). the groove has full a radius at the bottom of the grooves and the groove itself is cut 50 thousand more shallow that the cosi so there is 100 thou more material in this known weak spot. these are the cams i've decided to go with now.
these i'm sure aren't the only ones out there made properly but just the only ones i've seen.
these i'm sure aren't the only ones out there made properly but just the only ones i've seen.
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Seems like they need to go back to the drawing board and look at their mivec cam designs. Kelfords are great cams and they tend to do a good deal of research before they release a product but it looks like they dropped the ball on these as well as GSC and Cosworth.Hopefully they will rework their designs.
Last edited by URBANRCR; Mar 11, 2009 at 04:11 PM.
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I had this happen to me on a car I worked on, everything was torqued to manufacturers specs. snapped after a month of the car running with them if I remember right.
this serves as a warning the cams for the mivec(IX) from gsc kelford and cosworth are flawed in design. anyone who runs any of these should seriously consider removing them and asking the vendor for a refund . enough data has revealed that there is a major problem with these and motors are be ruined. no more excuses! kelford gsc and cosworth make great products but these cams were a mistake.
Last edited by PlanoEvo; Mar 11, 2009 at 04:53 PM.
I wonder how long the manufactures have been aware of the problem and what they actually plan to do about it. There are a number of Evos running big cams. With GSCs S2 installed, their new version, I can only hope for the best.
