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Hi All,

I have developed a little tap tap tap noise. Sounds like its coming from the head but not sure.
It is at the mechanics now but can anyone give me a quick diagnosis???

Richard.

I should add we just turned up the boost to 15PSI and 173rwkw. (please dont say rods, please)
We have now turned back down to 12PSI and 156rwkw.

It sounds like it might be going "pingpingpingpingping" rather than "taptaptaptaptaptaptap".

Definitely taptaptap, Tune is good. Tap is bad.

Well that's me out of ideas then!

bear2230 wrote:Hi All,

I have developed a little tap tap tap noise. Sounds like its coming from the head but not sure.
It is at the mechanics now but can anyone give me a quick diagnosis???

Richard.

I should add we just turned up the boost to 15PSI and 173rwkw. (please dont say rods, please)
We have now turned back down to 12PSI and 156rwkw.

taptaptaptaptap like lifters on startup?

taptaptaptaptap like lifters on startup?[/quote]

On start up but doesn’t go away and increases when revved. Not super noisy but you can hear from outside the car clearly

bear2230 wrote:taptaptaptaptap like lifters on startup?

On start up but doesn’t go away and increases when revved. Not super noisy but you can hear from outside the car clearly[/quote]

So it could be that the lifters have collapsed, or perhaps your oil isn't coping?

Tried changing it?

ozi_milhouse wrote:
it could be anything, but does it sound like piston kissing head? is it really loud?

I don't believe this is physically possible in the MX5 engine is it?

Yup, non-interference engine.
But, it does not sound good at all (ie. expensive).

Uncle Arthur wrote:

bear2230 wrote:taptaptaptaptap like lifters on startup?

On start up but doesn’t go away and increases when revved. Not super noisy but you can hear from outside the car clearly

So it could be that the lifters have collapsed, or perhaps your oil isn't coping?

Tried changing it?[/quote]

I'm thinking lifters have sh*t themselves. I think. Oil was changed 1 month ago at Mania when they did 25000km service.

ozi_milhouse wrote:Did you give it a good rev at higher boost?

Did you engine brake on down shift?

it could be anything, but does it sound like piston kissing head? is it really loud?

or did you amend tune? play with idle control valve?

could be anything.

High pressure fuel pump was installed and boost increased while on the dyno only. It was revved at higher boost but not over revved on down shift
Doesn’t sound like piston kissing head but haven’t heard many pistons kissing heads before. But not really loud.
play with idle control valve? I’m not sure.

lifters or injectors

bruce wrote:Yup, non-interference engine.
But, it does not sound good at all (ie. expensive).

Mother F@#ker

project.r.racing wrote:lifters or injectors

Much better

[quote="Uncle Arthur
I don't believe this is physically possible in the MX5 engine is it?[/quote]

IF it has spun a bigend bearing then the Pistons can hit the head
But with out hearing the engine Its hard to tell whats wrong

The last time I ran the race car on 14psi with STD rods it Broke 1 and bent 3.
1 was so bend that the crank balance weights where hitting the bottom of the piston
and making a horible noise.

not saying that it is the problem as there are over 400 parts inside the engine and anyone of them
could cause a noise is it fails

Russellb wrote:[quote="Uncle Arthur
I don't believe this is physically possible in the MX5 engine is it?

IF it has spun a bigend bearing then the Pistons can hit the head
But with out hearing the engine Its hard to tell whats wrong

The last time I ran the race car on 14psi with STD rods it Broke 1 and bent 3.
1 was so bend that the crank balance weights where hitting the bottom of the piston
and making a horible noise.

not saying that it is the problem as there are over 400 parts inside the engine and anyone of them
could cause a noise is it fails[/quote]

Holly F$%k Russell dont tell me that.