Tornado

I just ordered the J-Spec intake and exhaust cams. I've done a fair amount of reading on the subject from the various posts on this site. One thing that struck me was the difference between THE Man's Dyno and the one submitted by Phantom Cruiser.

The mod differences seem to be the exhaust and the header on Phantom's ride and the intake manifold on the Man's car. Will these items really account for the ~10hp difference in the final dyno numbers?

I have the Racing Beat exhaust and am looking for a header. I asked some questions on the OBX header Claims thread if anyone wants to answer them for me.

Thanks in advance.

Dave

zeus

Almost all of the time, the slight variations in output from identically set up engines, result from slight timing differences in valve timing. It is not uncommon for engines to come from the factory with the cams timed 1 to 2 degrees off from each other. From the factory’s prospective that’s close enough. Adjustable pulleys are popular with aftermarket and custom cams because they allow one to dial in the performance, but they can also degree stock cams just right too.

Of course there are variations from one dyno to another, as well as atmospheric conditions during a run that can effect output. The header and manifold could make a big difference too.

As for the header, OBX and HP both list P/Ns but neither has produced anything yet. The bastards. We are left with few alternatives. The affordable one requires modification of the EGR tubing first. Then any full header will eliminate the primary cat and require tricking the second O2 (OBDII) sensor to avoid the CEL. This 2nd sensor only checks for emissions compliance anyway. You can move it to down stream of the second cat and it will work to keep the CEL off, but what’s the point.

The first O2 sensor you don’t want to trick, and just about anywhere in the exhaust stream will work for placement. Any pipe you find will have a boss for that sensor anyway, the threads may not match the OEM sensor but that’s no big deal.

So get the Probe header, install a EGR boss and mod the tubing, then get a OBDII cheater and you're set. Unless of course you find you need to degree the cams.