donmik

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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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!

As mentioned above: Cam timing IS NOT the issue! Please understand this "Fact" Thank you.

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!

Very impressive! However I wouldn't be so confident in saying others don't have a vast knowledge in these fields... Whilst your theories maybe great on paper, they are merely that, theories! once applied in the real world factors change! But im sure you know this as obviously you have machined and built your fair share of engines.

So back to the original issue, after running some test with blah_blahs car tonight, I am confident in saying it is indeed the turbo which is not suited... (By no means am I saying this turbo is no good, as a matter of fact I think the numbers it has put down are quite respectable) The turbos biggest set back IN THIS APPLICATION I believe is the internal wastegate (which most of us assumed anyway) I played around with the actuator preload with no improvements, and got to the point were I totally removed the line from the actuator and blocked it... I still couldn't get it to hold over 24psi... Which only indicates to me, the back pressure is far to high and forcing the gate open under its own pressure! Thats all I have time for!

Let me ask this... Do you even know what your talking about? The fact that you are using big technical words only tells me you have no idea what you are talking about so you are just trying to confuse everyone...

Im an odd type of guy... Many years ago, back when we used flow benches, we were building a race engine, target power was just over 600hp.... Selected aftermarket heads for it, to which we copped a lot of criticism for as "they won't be big enough" Done our port work to it, and got them flowed... People litrally laughed at the results and mocked us... Went ahead and bolted the heads on, and sent it to the engine dyno... 650hp... So why would I choose to use a flow bench again?

Are you talking about flow or volume? Volume can be measured the same way a chamber is checked... But once you've been doing this for over 10years you start to get the hang of it... Where as many people thrive to get perfect port volumes, the fact of the matter is there is a lot more other important things to consider, as a few cc difference in a port is not going to tarnish a whole engines performance.

Nah, no flow sheets for the head. Due to past encounters with flow benches and results, I refuse to use them.

......Ummmm, cant say I totally aggree with you there hypergear.... A compressor map is made up of the efficiency islands based on a range of factors... one being shaft speed! As whilst I agree its probably not the most accurate way to tell, it is very evident that blah_blahs engine has already gone over the maximum "efficient" shaft speed of 145,000rpm... What causes the shaft to rotate? The turbine wheel! Another interesting fact I learnt today talking to the right people: An inefficient engine will run a higher timing advance to allow the extra time required to burn the a/f.... The more efficient the engine the less timing it will require with no power loss...

Ps. I Love scones!

I get and respect that scotty, dont think im trying to put you down or get you upset! I do believe a larger housing will have a minor effect of the lag, but I wouldn't class it as a lag "issue" Its a circuit car, get it to boost and keep it there! Are you saying fuel quality could be an issue?

Less power? I believe peak power figures were same, and what is power anyway? Torque x rpm? Why did the new motor create 30 more Newton meters of torque?? Cam timing is not the issue! If you cant get those exhaust gases out quick enough, it is eventually going to reverse flow back to the valve, those gases carry extensive heat, especially in the first stage of the burn process... more then enough heat to act as an ignition sorce for the fresh air/fuel trying to make its way into the bore...