Yesterday was (almost) the final step in getting RZ2's new motor ready for the Nationals ... 3 weeks to go! This work was necessary as the car had been running very lean, and giving the motor some hard work may very well have resulted in more ugliness. RZ2 has a HiTec chipped ECU, and I don't think the car's previous owner had ever checked to see that a/f ratios were where they should be. This dyno chart shows a run done on RZ2 after the head gaskets were replaced, but before the major rebuild. At this stage (late 2007) I knew the motor still had a major problem based on the oil still turning up in the radiator, and I was already preparing myself for a big hit to the budget. Check the a/f ratio ... about 13.6:1, too high, too lean, too risky. Peter (wykked) also has a HiTec chip, and after various upgrades needed his ECU recalibrated as well. So a date was set, a dyno booked, and Bob from HiTec was locked in to re-write the fuel and timing maps and anything else necessary. A very modern and well laid out facility, Chev's Performance Centre, 3 minutes away from home for both of us, was the host dyno for the day. Wykked was first on, and with more work for Bob to do, took up the lion's share of dyno time. Unfortunately, after getting a handle on the new fuel regulator, and without doing a serious power run, his day came to untimely halt with what is thought to be a clutch failure. The car still drove, but with some ugly mechanical noises, and would have to be trailered home. From memory, the highest figure achieved was 255.9rwkw, but at lower boost than Pete would normally run. Bob at work with tablet PC, Consult, and emulator, while Gary (Chev himself) handled the accelerator and dyno. Then it was my turn. Virtually immediately, Bob confirmed that the Z was running too lean. When Bob was ready, the first power run produced a run in the 220s. With continued tweaking and fiddling and another 12 power runs the 250.5 result below was achieved with a much better a/f figure around 12:1. However, in the higher rev ranges there was some coughing and farting, which just wasn't going away. The motor was still running a stock PFR 6B11 plug, and after checking local suppliers for a set of colder plugs without luck we called it a day. The manual boost controller was also playing up - no matter how we screwed or unscrewed, boost stayed at 20psi and was pinging. Bob allowed for this, and pulled some timing out. The wheels on the Zeds go round and round, round and round ...... Then, after mine was done and wykked was trailered, Jen (aka blondie) put her '68 Mustang on for some low speed runs to trace a carburetion issue. Gotta admit, a V8 sounds better than a V6 which ever way you cut it .... So,we go back again in 2 weeks time, April 4th. Me with new plugs fitted and hopefully a new manual boost controller - been told about a link to an ebay unit in the forum, so I'll chase that down, and Pete with what will probably be a new clutch. We had 5 hours of dyno time yesterday, and should get by with about 3hrs next time. Bob will be there again to complete both tunes. I'm already a lot happier about giving the Z track time at the Nationals, but after 2 years of Z grief, I've opted for another "protection" measure, and will have to find space for another vehicle on the driveway - I've put a deposit down for this .... See ya at the Nats!
interesting day Mikey.... at least both cars are getting sorted and one step closer to completion.... out of curiosity, did the mustang do any power runs??
Looking good and on schedule Mikey. Will catch up with you, Wykked and Blondie at Warwick. Cheers, Peter
That's a very linear power curve Mikey, looks nice and I bet would pull nicely on the road. Your old chart at 13.6 is deifnitely ping territory, especially at the power range.My AFR looks very similar to yours. I've been doing some playing and I reckon just from seat of pants feel have another 50 horsies. The manual boost controller on ebay is a Turbotech. Only bought another one for a Skyline owner last week, that's about 5 I have purchased now, all with ahappy customers. Just under $40 delivered.
Thanks Karl, a Turbotech has been bought and paid for on ebay, should easily arrive in time. Erik, thanks for the comments - I like them too .
Nice writeup Mikey, that place looks smick! Hope when I get my own place I'll be able to keep my garage that clean
looking good mikey, even the way it is now i bet 250rwkw is very nice to drive. curious about bobs decision to tune on the dyno. he has always been so against dyno tuning? cars looking schmik aswell
I was more interested in making sure the secondaries on the carb were opening properly Mark so didn't see what power it put out. Pretty sure it past 140kw while I was watching the screen but no idea what it made it to.
Bob does prefer to tune on the road but I needed the dyno because 6000+ rpm in 4th gear on the road = loss of licence.
hey man, sorry to hijack thread, but wat kinda cannons are these? im looking around atm for similar if not the same cannons for my NA. cheers mate
