broke my stage 2 exhuast cam into 4 peices and bent 6 exhuast valves at the track at 8500 rpm and coasted to a 14.5. Ran a 14.0 earlier while missing 4th, full exhuast, and into a head wind. I'm figuring stiff valve springs combined with shitty cast cores(brittle cast iron) is the problem. I was running Manley springs and retainers. i'd like to know what springs other people where running when they broke their cams and which cams those where. i've heard of juns breaking which are cast iron aswell. The only steel cams are todas and i wonder if those have ever broke which i doubt. I'm gonna be running the rocket motorsports springs next in my street motor and getting bigger and better cams.

 

yeah my friend broke his cams in half...crower stage 3 with crower springs n retainers...he bent a couple of valves...n some rocker arms....

 

Stiff springs IS NOT the problem. If cams are breaking then there is a problem with:

1) The cams themselves or
2) The head or bearing caps.

The loads and stresses a cam are exposed to are minimal, but the fatigue is what can kill a cam. If there were impurities in the casting core, or head was warped or bearings were not concentric this would cause excessive cyclic fatique stress, which is what will most likely cause a cam fracture.

 

What about coil bind?

Not that I think that is to blame here.

 

You broke them in the H22??

i was reading that the LMA's are the culprit in B series 1st gen heads.
dunno bout H22 though

 

yeah it was in an H22. I'm pretty sure 99% of the problem is the cams itself. Crower probably has one of the if not the most shittiest cores on the market. But i'm thinking get less stiff springs just to be on the safe side. you know i don't want this **** happening again. I'm just kinda pissed off i didn't get to dyno the car again cuz i just put in the Hytech header and damn that **** was pulling like a ******. Does anyone havee the spring rates or pressures of the major springs on the market like skunk2, crower, ferrea, portflow ect??


Modified by MrMike at 1:40 PM 6/30/2004

 

It's the profile.

 

http://www.crowersucks.com

 

crower valve train and cams are pieces of ****

their cranks, on the other hand, are top knotch and good stuff

 

Just broke a set crower h22 turbo cams during a 1000 $$$$ street race about a week go, broke both cams with in turn melted the intake side of the pistions. after they broke you can see what **** castings they really are WAY TO GO CROWER MULTI MILLION DOLLAR COMPANY CAN'T EVEN MAKE A SET OF CAM WITH IS WHAT THEY SPECIALIZE IN..............

 

show some pics

 

I honestly wonder how many of these are installer error or other factors.

While of course a poorly manufactured cam would be more susceptible to failure, there are plenty of other possibilities. Since I see more people running them with out trouble than I see breaking them, it makes me wonder.

 

when did you get your cams? They had problems with the vtec cams, but were supposed to fix them. I have had my 404z for over a year now and not one problem. They are also non vtec

 

Welcome to the broken cam club.. we also have broken a set of crowers.. stage 2.. but brian at crower sent us a new set at no charge.. but then we sold them ASAP.. LOL.. and never ran crower cams again.. we all live and learn the hard way.. but no one could of every thought that.. becus crower said they redesigned the cams with new metal.. "GUESS NOT"... call brian and bitch..

 

who broke a set of Jun camshafts?

 

looking at that photo album of the crower mishap/carnage makes my skin crawl.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CD5 Sedan &raquo;</TD></TR><TR><TD CLASS="quote">looking at that photo album of the crower mishap/carnage makes my skin crawl. </TD></TR></TABLE>

Honestly I don't think that photoalbum has anything to do with crower specifically.

It looks like a TI retainer failed?

What most people don't research, and don't realize is that titanium is a SOFT metal. They wear faster than steel, there is little we can do about it beyond some basic techniques that help but don't eliminate the problem. (nitrate coating, snap fit, smoothing the valvespring tops)

If you run TI retainers, you should check them often to make sure they are not getting excessive wear. If you didn't read about it, and don't check, that sucks but its not crowers fault.

 

all the brands listed that have ever broke in their career are chill casted rite have you guys ever seen a billet cam brake jus wondering.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4thGenReady2Go &raquo;</TD></TR><TR><TD CLASS="quote">who broke a set of Jun camshafts?</TD></TR></TABLE>

Do a search, theres been a few juns breaking on here every year.

 

I have used Crower cams in 3 different motors and have owned 4 different sets of crowers and have never had any problems with the cams at all!

I believe there may be some factory defects in a few but thats only a small %, so more than likely its operator/installer error, or someone that drives there car at 8000+rpm everywhere they go!

 

I have a set of Crower Springs/Retainers but the more i read, the more I realize that I don't need Ti retainers...picks like that are scary but most people don't give all the info. ****, for all I know that guy could have done something wrong or over-revved or something.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StyleTEG &raquo;</TD></TR><TR><TD CLASS="quote">

Honestly I don't think that photoalbum has anything to do with crower specifically.

It looks like a TI retainer failed?

What most people don't research, and don't realize is that titanium is a SOFT metal. They wear faster than steel, there is little we can do about it beyond some basic techniques that help but don't eliminate the problem. (nitrate coating, snap fit, smoothing the valvespring tops)

If you run TI retainers, you should check them often to make sure they are not getting excessive wear. If you didn't read about it, and don't check, that sucks but its not crowers fault.</TD></TR></TABLE>

I didn't know that, so how come companies like JUN recommend using TI retainers with their doublesprings and cams for H22? If it's a softer metal, why do people opt for it over standard (steel, aluminum?) retainers?

 

a. because its lighter
b. because the want you to use their valvetrain with they tested and designed to work with their cams

 

has anyone tried or is currently trying some magnesium based retainers? pros/cons of magnesium based retainers?

 

any time you use aftermarket parts don't just install them check clearances just like you would your crank. pull all your cam followers out and tourqe the caps. see if they will spin free. then plastic gauge all the caps. on our race engines we've had to polish the jonurals down on a lath so they spin better. .003-.006 works well. hell think about it if you aren't carfull tourqing the head bolts you can bur where the cams ride. but if the journals at the tail end of the cam is tighter than the front that belt is not going to slip.