I bought Chrismaxs old Nismo cams for a good price. Ive contacted Stephen Max and he says he drilled one of the two intake cams 1 or 2 degrees different from the other - which is why Chris had all these problems getting his car running right.

So we are thinking of re-drilling the cams at a new location, using the stock dowel pins\sprockets. I dont want to use the dowel pin adaptors-spacers for reliability reasons. I will only trust the stock dowel pins.

Now about timing - we need to drill the cams far enough from the old holes so they dont interfere - since these Nismo cams are 262 degrees duration, how much will the timing be bumped up - 275-280 or so... wouldnt that make them similar in duration to Tomei 272 or Tomei 280 cams but with less lift (10.5 mm vs 11.3 mm for the Tomei 280s).

What are your thoughts about advancing cam timing that much with the non-variable 3.0L timing chain setup... Im mainly worried about the idle, drivability at low RPMs. I am willing to set the idle to 1200-1300 rpm if thats what it takes.

The 2 exhaust cams will remain untouched as usual.

 

Swap vtc's

 

Sorry I am decided on using the stock 3.0 ECU for now. Thats the whole reason im doing cams. It was either a stock 3.5 with VTCs and 2002 ECU or no VTCs and aftermarket cams. It has to be drivable in the winter. No low end+progressive powerband=good off the line traction.

 

Advancing the cam = more mid-range power, worse idle and off-idle power. If you want better idle, off-idle power, and better top-end power, retard the cam. At the expense of mid-range power. Simplified of course...

 

Man.....I don't think there will be reliability issues with the spacers/adapters. I was going to buy these cams just because the spacers/adapters would allow me to make use of them even though they were drilled incorrectly but decided on another set. Like many have said, just have the things welded and I think they will be fine.

 

Aren't the Nismo cams grinded with lobes in a slightly advanced position to begin with?

 

Sell you some medical grade titanium to make the dowel pins out of

 

Can someone explain why the more aggressive cams have more duration then... Tomeis have 272 and 280 with 10.5 to 11.3 mm lift. Nismos are also available with 284 deg and 11.xx mm I believe. So the more agressive cams always have more duration (at least on the intake cams). Heres a chart from Tomei:

http://www.tomei-p.co.jp/inf/jpg/1400/87.jpg

So if I retard 262 deg cams Ill end up with closer to 240 degree stock cams and basically have the equivalent of a stock rev-up cam. How does that add up...

Heres a dyno of the same 262 nismo cams:

http://i23.photobucket.com/albums/b3...r/DSC00277.jpg

It seems to peak around 6200. Id like the peak HP to be around 6500-6700 rpms for a 7000 rev limiter. Do you think retarding the timing would help achieve this...

Did a little research and it seems you can run more ignition timing if the cam has retarded cam timing. Does this mean I will have more potential with a more retarded postion once I have the E-U...

The rear end is going to be a 4.36 limited slip - that means I will shift into 5th in the quarter - so I have every reason in the world to shape the powerband to be at its strongest in the 5000 to 7000 range for a 7k shift point. The problem is that since nobody has info on a VQ with ITBs Im not sure how I should set up the cam timing. In all cases peak power has to be around 6500-6600 RPMs. Then again with the right IM I guess its possible to achieve this even with stock cams.

On the flip side, maybe the ITBs along with a retarded cam position will move the peak too high to effectively shift at 6800-7000 so perhaps the better setup would be advancing the cam timing as planned and tune runner length on the ITBs to obtain the desired peak. ITBs are known to give a wide powerband so coupled with the advanced cam position maybe that would offer a meaty 5000-7000 range.

Because at the end of the day, no matter if I retard or advance... theyll still be more agressive than stock cams in every way so if a 6500-6600 rpm peak can be achieved on stock cams, then these will definately be able to peak that high no matter what - and maybe its better to have the better mid range along with that.

 

Ok after doing more research on this I understand it a bit better. Retarding cam timing makes the valves both open and closer later in the cycle thus moving the same powerband up.

I stumbled accross a rule of thumb that says for every 2 degrees of advance or retard, this will move the peak by 100 rpm up or down. So by retarding the timing I could move the peak RPM by a few hundred RPMs.