I've searched for info on this and found answers to some of my questions, but they just raised more questions.

I know the VE doesn't come equipped with an EGR system, and I understand that between that and the high compression ratio passing a dyno test for NOX could be pretty hard. Here come the questions:

Do you guys think that a custom plumbed EGR system could solve the NOX problem?

Does the USDM roller-rocker intake manifold fit the VE?

Should I try to adapt the EGR to the stock VE manifold or get a sheet-metal manifold fabricated?

This is the final major hurdle in my plans for a VE. You guys seem to have ironed out many of the other problems. Any help on this one would be greatly appreciated.

Thanks,
Ben
92 SE-R

Also, even some help on where to check for answers on the above questions would be helpful.

Thanks again,
Ben
92 SE-R

Originally posted by frkpwr
Do you guys think that a custom plumbed EGR system could solve the NOX problem?

Does the USDM roller-rocker intake manifold fit the VE?

Should I try to adapt the EGR to the stock VE manifold or get a sheet-metal manifold fabricated?



I would just plumb the stock EGR system onto the VE. This seems like the easist way to do it. Unless the roller intake manifold fits which I would check on this first. I just doubt that it would fit but I would check first.

I've searched all over and found the duration and lift characteristics of the SR16VE and SR20VE cams, but I can't find the Intake Valve Open spec, Exhaust Valve Close spec, or the amount of overlap. If anyone has these specs or can point me in the right direction, I would appreciate it.

Thanks,
Ben
92 SE-R

Thanks to maddjack's help, I can finally compare the valve overlap between the SR20DE and SR20VE cams.

If my calculations are correct(feel free to check them, this is new to me):
SR20DE
8*overlap

SR20VE
Low 0* overlap (no good for NOX)
High 48* overlap (nice)

Now I wanna see the SR16VE numbers.

On the rest of the NOX front, I am considering using 9.5:1 DE pistons to slightly lower the compression ratio and adapting an EGR.

I assume I'll have to tune the fuel map to compensate for the EGR. I thought about using the adjustable FPR, but that doesn't take into account the cam switchover or does it? Maybe I could use an AFC. Or could JWT fine tune the VE program to compensate for the EGR?

Also, I thought that since the High cam has such a huge overlap, I could use the RPM triggers to trigger a third solenoid which could disable the EGR system when the High cam kicks in.

Finally, to avoid much of this. I could tune an EGR to work with the high cam disabled and get it tested that way. Then completely disable the EGR after passing the test, and just retune every year.

Any comments would be appreciated.

Thanks,
Ben
92 SE-R

Originally posted by frkpwr
SR20DE
8*overlap

SR20VE
Low 0* overlap (no good for NOX)
High 48* overlap (nice)


Why not use adjustable cam gears? I used mine to decrease the overlap on my S3 cam equipped 11:1 DE motor in order to pass emissions. Granted, my state doesn't test for NOX but I would think you could find a happy medium with NOX, HC, and CO.

Steve

Good call Steve. . .

See, that's why I post. Although, I would actually be trying to increase the overlap. And again, I run into the problem that any adjustment to the cam gears would affect both the High and Low cams. And it looks like the Low cam is where I would need the EGR most because more overlap acts as an internal EGR, especially valve overlap past TDC.

Either way, I feel pretty confident that the engine can be tuned to pass emissions. I'm just not sure how difficult/complicated it's gonna be. Plus, it sucks that I can't test-n-tune it at home.

Keep the suggestions coming.

Thanks,
Ben
92 SE-R