DJZ's 280ZX

[gingofthesouth]

So close! Hope the dyno tune works out for ya.

[DJZ]

Well, an interesting day today. Got the call at about 10:30am that something wasn't right with the car, when I dropped it off it wasn't running on 6 and I thought it'd probably just fouled up the plugs again. They compression tested it and it had no compression on number 4.

Phil took the rocker covers off and found that the exhaust cam was broken in half pretty much in the middle, this probably happened when I put the head back together, I followed the instructions in the manual for reassembling it but might have just tweaked it slightly. So by the sounds of it the motor has never actually been running on 6, the exhaust valves on 5 & 6 have been closed the whole time and the valves on number 4 have been very slightly open. This explains a lot as to why I could never quite get it sounding right, strange smoke coming out of the spare ports on the inlet plenum etc etc. I did think about compression testing it after I got it running but I haven't got a tester and never got around to borrowing one.

I still had the original cams out of the motor so I took the exhaust one down, Phil put it in the motor and got it going again, luckily the valves on number 4 weren't bent. So it goes again but the clutch is slipping even on low boost and there is an exhaust leak somewhere, I'll see if Phil knows where it's coming from tomorrow.

The motor has been run in on the dyno and it's been tuned on wastegate pressure, I'll find out how much power it was actually making when I pick it up tomorrow. I heard it winding up when I was talking to Walter on the phone and it sounded pretty good! Does anybody have an RB twin or triple plate push clutch they want to get rid of?

[Kitch]

wow broken cam

thats a bummer, but great to have a definitive reason as to your probs.
at least overhead cams are easy to change

good luck for tomorrow, look fwd to hearing how much HP she's poking out

[Bartman]

Yikes!
I had my heart in my mouth when I read you had a broken cam. I hope all goes well for you mate.

[DJZ]

Thanks guys! My first broken RB bit, I'll have to try and get it back for a trophy.

[DJZ]

Picked the car up today, told it had 3 problems that needed to be sorted out before tuning it again:

1 - The clutch is slipping
2 - There is at least one exhaust leak, maybe more
3 - The boost is creeping, wastegate spring pressure was 8psi and it was creeping up to around 14psi at 8000rpm.

The clutch I was expecting to slip sooner or later, turns out it was sooner. The exhaust did sound like it was leaking from somewhere but I couldn't pin point it, it may be the v band on the back of the turbo, it was a pain to get it sealing up, I thought I'd got it but we did knock the exhaust a bit trying to get the car on the trailer. The boost creeping is a bit of a pain, I'll have to take the manifold off again and look at running some bigger pipe to the wastegate.

But, the car made 361rwhp @ 14psi as it was and to be honest it sounds really really awesome. I drove it home (with no brake booster) as I live like 2 streets over from NZEFI, gave it a little squirt and it sounds amazing. I've achieved my main goal which was making more power than the L28 did hah.

[Kitch]

congrats dude, very respectable, and sounds like you will have a great package, when you iron out the bugs

[gingofthesouth]

Awesome bro, glad you achieved your goal.

[Bartman]

Good shit!

[Dattochriswagon]

Holy Shit!!!!!
Thats some epic HP!!
Cannot wait to this thing unleashed!!