Metallic tapping noise?

[Silverstreak]

Ok, so I know the SR20 is quite a noisy lump anyway, but mine has developed a rather noisy metallic tapping noise which gets faster with the revs and is most audible when decelerating in low gears. I have just given it it's first proper oil change with Mobil 1 0-40W after running it in for 1000 miles on mineral oil. (Fresh engine build) oil and filter replaced at 200 miles too. This noise only started happening after transferring to synthetic oil.

I have 264 cam profiles, titanium springs and caps, rocker stoppers but have retained the hydraulic lifters and VVT..

It's also limited to 3.5k revs while I ran it in.

Please any ideas as I'm lost as to what it could be.. Pretty sure it's not VVT rattle!

 

[pegliobaglio]

Oil is too thin buddy most use 5w40 or 10w40 some use 10w50 even with the 5w40 I find mine quite noisy so may try something thicker next time

 

[Silverstreak]

Did wonder, couldn't get any 5-40W at short notice. Consulted Horsham developments and Jez seemed to think it would be fine.. Maybe not

I'll post a video of it once I get in from work!

 

[Silverstreak]

Also, surely a thicker oil would be detrimental as the SR has tiny oil ways. Wouldn't that affect top end oil pressure and cause insufficient oil spray for the cams etc? I could be wrong?

 

[pegliobaglio]

I spoke to opie oils before I bought my oil and they recommended a 5w40 for my car . If your unsure send them a MSG they are inthe traders section . If you tell them your spec they will be able to specify the correct oil for you

 

[Silverstreak]

Thanks for the advice I'll do that, was just reading their oil viscosity thread lol..
I think, if this is the cause, will damage occur if I leave it with the 0-40W in for a while? Or does it just sound awful?

 

[pegliobaglio]

Wouldn't think it will cause fame mate as generally thinner oil gives better start up protection so unless your ragging you car hard a lot it should be ok. Best off talking to them though they are very helpfull mate. Mine sounds pretty loud too more noticeable with the 5w40 than 10w40 but car runs perfectly...

 

[Silverstreak]

Here's a quick vid of the noise..

https://www.dropbox.com/s/ip2i1oh1bj1p4uw/2013-10-26 15.10.11.mov

 

[spoonman]

1st go back to the guy who built it and start with "what the hell do you call this"............ could be lifters and he may have just forgot to bleed one, or worse, its the bottom end, hell ask him what type of engine assembly lube was used?...... hope its just a lifter, they are noisy little buggers when they collapse

 

[Auss15]

"""I have 264 cam profiles, titanium springs and caps""You will not be able to keep the VVT from dying once you do this.....Cams and stiffer springs are a death sentence..

 

[Silverstreak]

I built the engine, used millers line I think, and all the lifter were bled when fitted.
I'm thinking the cause of the noise is using oil that is too thin, but will only know when I change it. Otherwise, it runs really well, good oil pressure, temp etc. the air fuel mix is spot on, the only thing that's off apart from this tapping is the idle from cold is a little all over the place.

With regards to the VVT, I was led to believe that it would be ok with this cam profile, and only needed changing out if I went for a more aggressive profile? Could I just disable it by removing the fuse marked engine? Would that work?

 

[spoonman]

its ok as in your valves wont smash into the pistons when it extends the duration, but what Auss15 mentioned might be spot on.
Not sure what cams exaxtly you have.
What is your timing set to? as for some cams you are meant to alter them by a few deg which as you know is where adjustable cam gears come in, some i think are meant to be altered by something like 5deg if you want to keep the VCT or remove it I cant remember which way around it goes.

 

[spoonman]

here tomei have this on there web site, is its of any use

http://www.tomei-p.co.jp/_2003web-catalogue/e076_cam_SR20DET.html

 

[Auss15]

The stiffer springs will do it, I don't know anyone who hasn't fitted aftermarket springs and not have the VCT cam fail at a later date

 

[Silverstreak]

Dropped it off at knight racer this morning for a full check over and a change to Fuchs Titan race 10-50w. Hopefully find out what's tapping!

Thanks for the advice guys. I shall add adjustable gears to the shopping list. Will it still kill the VVT gears if I disable the VVT?

 

[Silverstreak]

I have Brian Crower cams FTW, Horsham developments set the timing up.

 

[Chriscooke]

Mine sounded a bit like this after fitting my uprated springs/retainers, 260 procams and new rockers. It turned out to be a couple lifters that needed bleeding again.

The vvt sprocket fails on all sr20dets at some point so I wouldn't worry about it too much.