RB30det dyno tuning issues!

[the_tonkau]

Specs-r33s1-25det head on s1 rb30 block, 8.3-1 comp/forged, std cams, vct enabled, rx7 550cc inj, halbro @ 40psi, PFC. GT35 60ar .82- After 2000klms running in we attempted a decent power tune. It started pinging @ only 230kw atw. taking out heaps of timing and adding WAY too much fuel and still seems to detonate. The head is a little noisy, when using the "knock box" on the dyno you can pick it up. The head was only crack and pressure tested when the bottom end rebuilt. Has anyone heard of a faulty knock sensor? Is my head setting off the knock sensors? After another attempt of tuning on a fresh tank of fuel(mobil 98) it seems to have gotten worse!!! We are down to 190 kw atw to stop the pinging. Its like something is changing as we go.... very weird...Any ideas gentleman?

[R31Nismoid]

then GT35... why does it have a .6 comp?

isnt it a .7 on the front of it?

Knock sensors can indeed be faulty, wouldnt be the first one to raise a false alarm

[the_tonkau]

yeah, had a custom front cover made by kyp @ atp , didn't want to change my all intake piping from 3" to 4".

[BBQ]

What spark Plugs are you using and at what Gap? Try running a colder heat range on your plugs if you aren’t all ready?

[Sydneykid]

Specs-r33s1-25det head on s1 rb30 block, 8.3-1 comp/forged, std cams, vct enabled, rx7 550cc inj, halbro @ 40psi, PFC. GT35 60ar .82- After 2000klms running in we attempted a decent power tune. It started pinging @ only 230kw atw. taking out heaps of timing and adding WAY too much fuel and still seems to detonate. The head is a little noisy, when using the "knock box" on the dyno you can pick it up. The head was only crack and pressure tested when the bottom end rebuilt. Has anyone heard of a faulty knock sensor? Is my head setting off the knock sensors? After another attempt of tuning on a fresh tank of fuel(mobil 98) it seems to have gotten worse!!! We are down to 190 kw atw to stop the pinging. Its like something is changing as we go.... very weird...Any ideas gentleman?

If the fuel and ignition timing are OK, then my guess would be inlet air temp. What intercooler are you running? How is the dyno fan (we run 2, one for the radiator and one for the intercooler). Have you tried wetting the intercooler with water? Have you got an infrared pyrometer for checking the primary exhauts pipe temps or and EGT gauge? That will also tell you what is happening temp wise.

Interesting problem, please keep us in the loop:cheers:

[the_tonkau]

Intake temp... interesting not thought of that. We have always used the same dyno and the same cooling fans. The only thing that has changed since the rebuild is the 3-litre block and the new turbo (mounted further from the exhaust manifold with a spacer). In the old set-up we ran up to 20psi through a t04e and the 2.5l engine to get 250rwkw with good intake temps. The fmic is massive although I have yet to set-up a water spray, the dyno does use an intake temp sensor which sits in front of the filter and seems to be working ok. I am leaning towards the noisy head setting off the sensors. I am going to do the valve clearances and change the knock sensor and see what we get. Feel free to keep the ideas’s flowing gentleman, will post the outcome for those interested.

cheers

[BBQ]

Intake temp... interesting not thought of that. We have always used the same dyno and the same cooling fans. The only thing that has changed since the rebuild is the 3-litre block and the new turbo (mounted further from the exhaust manifold with a spacer). In the old set-up we ran up to 20psi through a t04e and the 2.5l engine to get 250rwkw with good intake temps. The fmic is massive although I have yet to set-up a water spray, the dyno does use an intake temp sensor which sits in front of the filter and seems to be working ok. I am leaning towards the noisy head setting off the sensors. I am going to do the valve clearances and change the knock sensor and see what we get. Feel free to keep the ideas’s flowing gentleman, will post the outcome for those interested.

cheers

I will ask again, What plugs are you running? Also what is your base timing set at ?

[the_tonkau]

standard base timing and the usual ngk BCPR6E copper plugs closed right up to handle the boost! idle is average but it doesn't start missing until you get over 20psi.

[BBQ]

standard base timing  and the usual ngk BCPR6E copper plugs closed right up to handle the boost! idle is average but it doesn't start missing until you get over 20psi.

Try running 8's that should help with your problem.

[Butters]

Your base timing might be right and you may pull out heaps of timing in the ecu ...

doesn't mean your cam timing is correct ...

Any chance you got the teeth out when you setup the timing belt ?

Just a thought

[the_tonkau]

Your base timing might be right and you may pull out heaps of timing in the ecu ...

doesn't mean your cam timing is correct ...

Any chance you got the teeth out when you setup the timing belt ?

Just a thought

<{POST_SNAPBACK}>

Mmmmmm, the chap who built the long motor should be on the ball with the cam timing, but its good idea and I might revisit that line of thought. I have yet to have the cams out to check the hydraulic lifters to see if they are ok. Need more time.......

BBQ, Are you suggesting colder plugs will help the "pinging problem" or the missing problem after 20psi?

Thanks for the input gentleman.