Adriano

Blitz had one for sale, ask him he would know(I think it was greddy)

I would get rid of the Fuel Pressure regulaor, the stock one is fine for 400RWKW, just run 10-11 psi and get it tuned on the dyno. Fiddling with the numbers like that on the road is a sure way to blow a motor or turbo.

Check the ignition timing, fuel pressure and do a diagnostic check

Warpspeed, i was wondering if you have any more imformation on this problem with wastespark(ie where you have seen it occur) I would have thought blowing back through the inlet valve would be most likely to occur at idle, as there is the least amount of ignition timing out of the whole map there. I also would have thought it would be far more prevalent in a N/A motor, as they have far more overlap and duration. Looking at this, would indicate that this camshaft selection would have the problem, as the inlet valve is defiantely open when the sparkplug fires, and this defiantely isnt a big cam, however the fact that the piston is still rising means that i can only conclude that there cannot be any scavagening, and no A/F mixture entering the combustion chamber. I think the only reason the inlet valve starts opening BTDC is so that once the piston starts to decend, the valve already has enough lift to allow the A/F mixture to enter. One car i built years ago that would be most likely to have this problem was a V6 commodore that made 240RWKW with N20 N/A, it had wastespark with multiple spark discharge(which could only make it more likely to blow back) and a camshaft duration of over 300deg which is far more than almost all turbo motors??

IMO putting the AFM in the bigger pipe will work perfectly, just need to figure out which AFM to use, a nismo GTR one may be the best, as they use a 65mm pipe and handle a fair but of airflow, so upgrading it to a 100mm pipe should make it read heaps.

Is it leaking from the sensor itself or where the fitting screws into the block?

Sorry paul i would have to disagree, when a map sensor voltage goes flat, it hasn't run out of resolution, if the boost goes higher, the voltage wilol change, if the maf is out of resolution, and the boost goes up, it will just lean out.

What, you mean like stock rb26 ones

Im running a MSD dis-4, and 3 M&W double ended cdi coils, fat as spark, only about $800

But unfortunately the autronic cdi is only 4 channel, so to do a direct fire cdi is mare like $2600 PS how much are you getting the sm4 P & P for?(PM me if you like)

Neo, but an emamage is heaps better.

Intercooler pipe blown off hopefully, or could be blown turbo.

The more you drive it, the more damage you will end up doing to the motor, busted ringlands are an engine rebuild job, start saving, because it will be february by the time it is fixed.

Youll have to factor in the cost of the ignition multiplexer to run the splitfires if you dont want to run them in wastespark, as the SM4 only has four ignition outputs

The base fuel pressure may not be that much different, but a 2:1 malpassi will add 60 psi to the idle pressure if your running 20 psi, so 40+60=100 psi, tell me thats not a lot of fuel pressure.

^^^how does consult tell you if the coils are stuffed?

Um gorgasm, do you think the power difference in the two power runs could be due to the different boost being run, 11.5psi vs 6.5psi.

Put the stocker BOV back on and see if it fixes it, ill bet it does, and your fuel economy.

They are rare, and there are rebadged normal pfc's getting around, buyer beware.

Neither are appropriate, you will end up with >10:1 comp. R34 neo throttle body is basically the same as r33 except it has the TCS butterfly on the front, no probs fitting a Q45 one to the greddy. IMO save the $1300 for the greddy/Q45 and do the motor properly, maybe with an rb30(then you can just use rb30ET forged pistons to give you high 8's:1 comp)

No dramas at all

Does it leak under full load? Or only while cruising?

Sorry, i thought it was an sm4

^^sorry, if the BOV has blowby, can i bore it out and fit a forged piston with chromemoly rings