So I recently did a bit of work to my Z including a donor NA engine and new turbos and fixing a bunch of other stuff that was broken and figured I'd put the details up here so there's a bit of information on high-comp builds. First, the results Before: one seized turbo, vacuum leaks everywhere, Top Secret chip tune, about 120psi per cylinder but not ring wear. It actually ran reasonably well like this for about two years, including some track time. After: New GT2554r turbos (JWT sport 530BB) with AMS mani's and Z1 split dumps, Nismo 740cc's in CZP/300deg rails, HKS front mount kit with Selin twin MAF side intakes and Nistuned to ~230rwkw. No boost controller, just wastegate 10psi. Pretty happy with those results for now, definitely not a 'finished' car but putting down the spanners to get some track time in until something important goes bang. I'm going to try go through how I installed various things over time so people have a heads up on fitment problems I found with the tubos, dumps and oil lines. Feel free to ask questions but please do not trash my thread by pointing out that high comp turbos are a bad idea etc. Feel free to make a thread in Z non-technical if you want to flog that horse.
So far from 80-85 but I haven't had a chance to give it a proper work out yet, I also installed a big full flow oil cooler which probably helps. Have a wakefield circuit club day booked for 9th of june, will let you know after that. Oh, and an ASI three core radiator and AC delete. At the moment I'm using an NA radiator fan because the plastic is in better condition but can swap back if I need to.
Will do, feel free to ask questions if there's anything in particular you're interested in, might get me motivated to write stuff up. Unfortunately I don't have to much technical information on how/why the build works but I can give my theory behind various choices. When you say 10:1 do you mean a standard block with 10.5:1 or are you doing a custom rebuild?
I figure NA motors are more common and cheaper, might be a PITA with more boost though, I really don't know whether mine has more potential or is pretty much tapped out. With e85 and other goodies it would probably be a weapon. Still not an economical car though, 16L/100km around town which is surprisingly worse than it was with the vacuum leaks I need to contact the tuner again and get some more info from him, that dyno chart isn't exactly informative.
Get the AFR reading too. If its as rich as you mentioned to me. ask if can be safely leaned out a little. the 300zx runs a bit on the rich side from factory. However there could be a good reason for it.
Tuning isn't something I was willing to try and learn myself so I don't know what the map looks like but based on ECUtalk max values it runs between 45 and 5 but that probably doesn't tell you much
My motor is a factory TT and im planning on forged pistons to bump up the comp ratio. Will be using Nistune too.
lol, just wanted a title that had a little more character than 'high compression turbo' and that was about the best I could come up with
Should be an interesting build, what are you hoping to achieve with the higher compression? What turbos are you looking at? So long as you keep water, oil and intake temps in check 10psi seems to be fine. Also I'm running heat range 7 plugs http://conceptzperformance.com/Cart/description.php?II=1163&Car_Type=300 not sure if they're important but they work well.
Well, definitely no temperature problems at the track in winter. Air temps today were up to 14 so not much of a test but water temp didn't go past about 95 C and oil temp, taken from the filter tree post-cooler, didn't get over 90 C (I think, forgot to check peak readings) (almost too cold). Due to lack of grip and skill I couldn't actually push the car to its limits so will wait and see how it goes in summer.
So reminded that I'm way over due for an update to this by a recent thread. The engine blew a headgasket ages back and there was a freshly refurbed unit going for cheap locally so figured was more sensible to just swap again. It went at about the 5000km mark and I think it was just bad luck because it survived fine at a couple of track days and some anger in the hills but one day just drove to the shops and when I got home could hear it gurgling into the overflow, had a couple hundred mL of oil in the top of the rad. I had intended to pull the motor apart for a post mortem before updating but still haven't gotten to it. Maybe one day.
https://ztunerblog.wordpress.com/2016/02/29/na-t-the-new-trend-for-2015-16/ Have a squizz at that boys. High comp forced induction to the death
Shame, high comp boost with E85 wunderfuel is the way forward I reckon. Plenty of go off boost and a torque curve on boost like a mountain for the win. Looks like it had plenty left in it, revving to 8500?
