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Been there...

Big single exhaust on a vg30, wideband in tail showed 11.5:1. Single cyl running way lean due to injector not flowing however being masked by the other 5.

Yeah this is right. If using a single wideband then you have to remember that there are 6 cylinders feeding the one, and you can have 5 really rich and 1 lean cylinder and the wideband will tell a story somewhere in the middle

Change ecus? Could be a nistune fault?

in what way? If they are having to pull out timing to stop detonation I can't see how our why the ecu would add timing and make it ping. If anything the ecu would pull more timing.

The thing to check that had been suggested is what timing out is actually running with a light on the dyno during the pull. As I suggested on the first page, If the cas isn't giving a clean signal the ecu could "lose track" of where the actual position of the engine is and therefore fire at the wrong position. Nistune can log what timing is being run, and that shows up if timing is being pulled (or added) from what was expected, but the end result has to be checked with a timing light, during the run.

I'm with you on that Ben.

1. Physical check of the ignition timing, during the run. And have a spare CAS handy to try as a replacement anyway.

2. Physical check of cam timing, using degree wheel. If the head has been skimmed or block decked, I would not accept that lining up the timing marks would suffice. Previous comments indicate that the cam timing was checked properly.

Nothing wrong with current turbo, it is big enough for 400rwkws+ on E85.

The power tread seems to be very similar to my KIA sportage, it is a high comp 10:1 motor how ever. Didn't like timing but still took more then the OP's R34. Fitted a couple of turbochargers on it, and larger turbochargers do result in a slight power increase every time.

The new turbocharger is for the XR6 BA engines, bigger in both larger compressor and turbine. I think it will do 530rwkws on my car. I don't have much time on it currently. But following the turbo size to power tread, it should be sitting at 350~370rwkws mark on OP's car. It is not the right way, how ever is a possibly solution on getting more HP.

fit a new decent intercooler setup, if this fails remove the timing belt and bottom pulley and re-set timing correctly.

sometimes they can be a bitch to get right, i once gained 80rwkw from re-doing the timing that was already "correct"

  • Like 1

If the bottom timing marker is showing TDC but the pistons are either side of TDC, there are problems that need rectifying.

Likewise if there is a misalignment error between cam timing marks, you won't see the valve at full lift when it is supposed to be.

A suggestion early in this thread was to bypass the I/C and run something simple outside the car to trial. That 180 degree bend for return flow piping can't be good, although it's hard to see that being the cause of all problems.

Double or triple checking the timing setup costs only time, changing the I/C and piping costs parts and time.

I like hypergears suggestion!! :)

As for cam timing, I noticed the suggestions of using a degree wheel...

Use a degree wheel for what?

Does ANYBODY out there have the standard OEM camshaft timing specifications?

IO/IC/EO/EC & LSA for advertised AND @.050" specs??

If not then a degree wheel is useless...

The only way the cam timing is out on this engine is if nissan cut the key way in the wrong place... (highly unlikely)

Please stop wasting time with suggestions of cam timing!

Thank you! :)

Here's the thing. Pop #1 plug out and make sure that the piston is at TDC when the mark on the pulley says it is. And don't pretend that it's not possible for this to go wrong. Balancers have been known to slip.

Once you have done that, you can then start to have some faith that when the marks on the cam pulleys line up when they're supposed that they are doing it ACTUALLY when they're supposed to.

I like hypergears suggestion!! :)

As for cam timing, I noticed the suggestions of using a degree wheel...

Use a degree wheel for what?

Does ANYBODY out there have the standard OEM camshaft timing specifications?

IO/IC/EO/EC & LSA for advertised AND @.050" specs??

If not then a degree wheel is useless...

The only way the cam timing is out on this engine is if nissan cut the key way in the wrong place... (highly unlikely)

Please stop wasting time with suggestions of cam timing!

Thank you! :)

Cam timing is also affected when the head and block are skimmed , as the distance is shorter the timing is retarded.

LOL

GTSBoy, I think you need to invest in a leap frog...

They are a wonderful device that makes learning to read a breeze... they have all different age groups available so im sure you'll find one to suit you...

For the rest who can already read,

CAM TIMING IS NOT THE ISSUE!!!!!!

I know this cause it has been checked, double checked and then triple checked by a few people, using the correct equipment. Including the engine builder himself, who happens be be me!

This is the idea of this thread, to brain storm ideas, not be ridiculed over basic items...

We have a few more tricks up our sleeve to try, but my gut is pointing to an electrical issue, the car is just too on song to be mechanical...

Although it is not being ruled out!

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