Jump to content
SAU Community

Recommended Posts

Anyone got some tips as to what is going on here.

Cam tech 270- 9.5mm cams no vct

Shimmed to

.010" intake

.012" exhaust

+\- .001"

Pretty confident of the clearances, have checked twice. Cams don't appear to be hitting anything. Can't see any marks on Pistons (checked with bore scope). Listened with stethoscope and it sounds valve train related...

Running performance springs.

Stock cams were quiet. Same springs just changed clearance

Edited by Huzqld
Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/
Share on other sites

I'm no cam expert (and no idea how to diag by the sound of it), but how did you decide on the clearances and are those hot or cold readings?

http://www.sau.com.au/forums/topic/397382-rb25det-neo-r34-gt-t-valve-clearances-solid-lifters/

Workshop manual in the above thread says 0.31mm intake and 0.51mm exhaust when cold.

0.31mm = 0.012" which is close to your figure.

0.51mm = 0.020" so your exhaust side has about half the clearance it should have

Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7538683
Share on other sites

Have asked camtech. They Aren't really sure what's going on. Obviously more investigating to do.

But always Good to see if anyone else has had issues similar

Came up with those clearances as that's what it says on the cam card they are cold readings.

You are right though the factory cams do run with bigger clearance and that is what I had the stock cams set to and the engine was quiet as.

Edited by Huzqld
Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7538777
Share on other sites

Not running vct in mine anymore.

Triple checked the clearances and it is as per cam card.

Retarded the intake and advanced the exhaust just to see if the noise changed (doing this should effectively give more piston to valve clearance?)

No change in noise.

Will keep investigating.

Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7539155
Share on other sites

The VCT assembly will still need some form of lubrication even if you're not using it. I remember reading some issues a while back about someone swapping heads and didn't keep the VCT oil feed and then had cam bearing issues. But if you are using the stock head and have just unplugged the actuator electronics then it will be fine. Didn't realise the cam had to be modified with a gallery too, sounds interesting.

What viscosity of oil are you using?

Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7540445
Share on other sites

Whoever originally done the vct setup on this head has done it a completely different way to what I've seen them done. They drilled down through the cam gallery and into the vct feed and grub screwed the top hole.

I found the thread somewhere but can't find it now.

But it hasn't worked, the vct half kicks in and then the car just idles normally again. (When testing at idle) made no difference to dyno graph either.

Plus it's an auto with a 3k stall and will probably go bigger down the track.

Didn't check the valve springs honestly (we should have) but they should cope with that lift.. They aren't stock springs and plenty of people have used them on bigger cams then this. They are the 'performance valve springs' springs and ti retainers.

Not sure what you mean by weight on nose of cam, but am only running adjustable gears.

I've packed the cams up and sent them back to camtech to check out.

Put the stock cams back in just to make sure and it's back to being very quiet.

Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7540556
Share on other sites

  • 2 weeks later...

Whoever originally done the vct setup on this head has done it a completely different way to what I've seen them done. They drilled down through the cam gallery and into the vct feed and grub screwed the top hole.

I found the thread somewhere but can't find it now.

But it hasn't worked, the vct half kicks in and then the car just idles normally again. (When testing at idle) made no difference to dyno graph either.

Plus it's an auto with a 3k stall and will probably go bigger stall down the track.

^

The solenoid seemed fine, maybe it was the gear, not really sure. Anyway, no more.

Link to comment
https://www.sau.com.au/forums/topic/456825-neo-noisy-cams/#findComment-7547666
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Hi, SteveL Thank you very much for your reply, you seem to be the only person on the net who has come up with a definitive answer for which I am grateful. The "Leak" was more by way of wet bubbles when the pedal was depressed hard by a buddy while trying to gey a decent pedal when bleeding the system having fitted the rebuilt BM50 back in the car, which now makes perfect sense. A bit of a shame having just rebuilt my BM50, I did not touch the proportioning valve side of things, the BM50 was leaking from the primary piston seal and fluid was running down the the Brake booster hence the need to rebuild, I had never noticed any fluid leaking from that hole previously it only started when I refitted it to the car. The brake lines in the photo are "Kunifer" which is a Copper/Nickel alloy brake pipe, but are only the ones I use to bench bleed Master cylinders, they are perfectly legal to use on vehicles here in the UK, however the lines on the car are PVF coated steel. Thanks again for clearing this up for me, a purchase of a new BMC appears to be on the cards, I have been looking at various options in case my BM50 was not repairable and have looked at the HFM BM57 which I understand is manufactured in Australia.  
    • Well the install is officially done. Filled with fluid and bled it today, but didn't get a chance to take it on a test drive. I'll throw some final pics of the lines and whatnot but you can definitely install a DMAX rack in an R33 with pretty minor mods. I think the only other thing I had to do that isn't documented here is grind a bit of the larger banjo fitting to get it to clear since the banjos are grouped much tighter on the DMAX rack. Also the dust boots from a R33 do not fit either fyi, so if you end up doing this install for whatever reason you'll need to grab those too. One caveat with buying the S15 dust boots however is that the clamps are too small to fit on the R33 inner tie rod since they're much thicker so keep the old clamps around. The boots also twist a bit when adjusting toe but it's not a big deal. No issues or leaks so far, steering feels good and it looks like there's a bit more lock now than I had before. Getting an alignment on Saturday so I'll see how it feels then but seems like it'll be good to go       
    • I don't get in here much anymore but I can help you with this.   The hole is a vent (air relief) for the brake proportioning valve, which is built into the master cylinder.    The bad news is that if brake fluid is leaking from that hole then it's getting past the proportioning valve seals.   The really bad news is that no spare parts are available for the proportioning valve either from Nissan or after market.     It's a bit of a PITA getting the proportioning valve out of the master cylinder body anyway but, fortunately, leaks from that area are rare in my experience. BTW, if those are copper (as such) brake lines you should get rid of them.    Bundy (steel) tube is a far better choice (and legal  in Australia - if that's where you are).
×
×
  • Create New...