| As many of you have noticed, my participation in the forum has dropped off drastically over the past half year or so. This has been primarily due to the birth of our first child which changes perspectives and priorities drastically. Secondly, I dropped a rebuilt engine into the Z last January but it has basically sat in the garage doing nothing since then. I did do a dyno after the rebuild back in the summer but did not post the results because they were extremely disappointing.. max of 336rwhp at 19psi on Sport 600's is not something to publicize. I didn't have time to mess with it or figure out the problem so.. the Z sat some more. A couple of weeks ago Damon and I decided to make a road trip to SGP and I took the Z down to let Kyle lay hands on it. After a few days Kyle called me and said he figured out the power problem. Somehow my timing was at 9 degrees. Now, I still maintain that I know how to set timing and I had set it at 17 (to lower EGT temps a bit). BUT.. .I'm the only one who has touched the timing so I guess I have to eat that humble pie. Yesterday Kyle put it on SGP's Dynapack dyno (neat stuff) and here are the results. I searched on here and found that there is strikingly little information on Sport 600 dynos, so here's more to add to the pot. Looking at the few examples that do exist, it appears that I'm right in line. Synopsis:
433rwhp @ 17psi
475rwhp @ 20psi
525rwhp @ 26psi (104 octane) Compared to my prior best dyno about 18 months ago I had ~425 @ 19psi and 478 @ 23psi, so it is running stronger since the rebuild. Bolt-ons are all the same except I switched 3" open down pipes to Greg D's split flange (original design). I'm running a regular JWT 555 single POP chip with AFC and dual MAFS. Surprisingly the A/F curve was not off by much and Kyle said he only had to dial out -4% max to get a perfect curve. (A/F curves are not shown on the images below). On to the pics: 17 psi
 20 psi
 26 psi
 And one with everything combined for easy comparison (the 17psi one was scaled to match the scale on the other two) 
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ZWEETT returns... - 
