Agno's 1975 260Z.

[Agno]

Carbs are well and truly on. It was dynoed with a rock solid 92rwkw, which seems a bit low but I'll take it. All I can say is WOW. The new carbs have completely transformed the car! It now has torque everywhere, makes awesome noises and gets surprisingly good fuel economy.

 

It's first test was a weekend sprints event at Wakefield Park last Sunday. It was a bit of a long drive for the old girl but she did it easily and averaged less than 10L/100km doing it! At Wakefield I managed to do a 1:17.57 on street tyres and overall I think I could have found another 1.5-2 seconds a lap with a bit more practise quite easily. Some photos from the day:

 

At the track after the first session fuel started rushing out of the tank breather like so:

A bolt in the breather and cracking the fuel cap at the end of each session solved those problems, but now I think I might have a new problem:

 

Plugs 2, 3 and 5 were quite oily. I've cleaned up the plugs and I'm going to take it for a short drive tonight and see if they oil up again. When I changed to the triples I put a little venty thing on the valve cover breather and the breather on the block has had another little filter thingy on it since I bought the car. If it oils up again does this mean I need a catch can and this will make it go away or do I have something a lot more worrying on my hands?

[Scoota G]

Yea you can see that the No 3 cylinder is the same one you have the hose from the rocker cover running to. Most prefer a catch can! Check how much blow by you have by taking off the oil filler cap while idling.

 

[Riceburner]

Seems like a lot of oil on 3, but there's also oil on the head. Maybe that plug was a little looser than the rest?

 

I run my crank case breather straight into cylinder1 through a PCV valve, similar to factory. I've never had oil deposits build up like that before. Could be a sign the rings are getting a bit tired.

[Agno]

The plan longer term was to get a Prince 2000GTB style airbox and plumb the valve cover breather back into the intake. On the track it is pretty obvious that the engine is breathing very heavily because my filter on the valve cover was saturated in oil after each session. I left that down to deliberately overfilling the motor with oil to protect it on track.

 

After the clean up, tightening the spark plugs tighter than I usually would and 40kms of driving I don't have any misfire present, it was a bit dark to see the plugs or motor though so I will have to check tomorrow. Fingers crossed the motor isn't dying.

[Agno]

Well, misfire came back. Oil on plugs 2 and 3 again after very mild (freeway) driving. I'm organising to borrow a compression tester over the next couple of days and seeing what's happening. Not feeling good about this

 

 

[Roberto]

Alex, have you still got too much oil in the engine? If so, drain it to proper level and see if that fixes oily plugs.

[Agno]

Apologies for the photoless updates guys, but I might rename this car to Lazarus.

 

After sitting idle for a couple of months, I decided to take it to the CSA/NDSOC show and shine at Docklands. Once I got it started it was firing on all 6 like a champ!

 

After scratching my head for a while and having a play with the car over the last couple of weeks I have worked out that it is fouling plugs up at idle. A nice long run on the freeway or some revs clears the plugs up again and it's back to it's normal self.

 

The other two issues I have are that it is a real prick to start, backfiring through the carbs and requiring chokes or lots of pedal pumping to get it going and then once it is going it does not want to rev over 4500rpm or thereabouts regardless of how warm the engine is.

 

The car was fine and revved out cleanly at Wakefield a couple of months ago so I'm a bit confused. The distributor hasn't been recurved to suit the triples yet (which is why I think it's hard to start, not enough advance at idle, currently 15 deg) but could a lack of timing be why it does not want to rev up top?

 

I should add that I have checked the linkages, jets, air filters, fuel filter and watched the exhaust for anything and it all looks good, not blocked and pulls very hard up to 4500rpm.

 

Thanks guys!

[C.A.R.]

Take it down to Les Collins & get him to tune it.

 

If it's not the tune, I guarantee he'll find the issues(s) with it.

[peter t]

Hi Alex, might be a vacuum leak. A good quality guage will pick this up but as Lurch has posted, an expert may be called for.

[Agno]

I feared as much, sigh. More money I can't afford, but that's the way with old cars I guess!

[hash76]

G'day Agno, don't know if you've already seen this, but I came across this familiar sight in a blog that I read.

 

scroll down some:

 

http://japanesenostalgiccar.com/2012/11/20/events-2012-skyline-nationals-part-02-australias-insane-1980s-nissan-touring-cars/#more-23701

[Agno]

Cheers man. I saw the first instalment but I must have missed that one, awesome!

[Agno]

So the car has been pretty much in hibernation since September, luckily it's temporary home is nice and cosy!

 

With some nice weather and time off I decided it's time I finally go and find out why this thing is such a pig to start and doesn't want to rev. So off come the carbs and exhaust for new gaskets and to check for leaks:

 

What do I see here?

 

Aside from the fact that it is a bolt and not a stud screwing into the head, the way the washer is sitting on the manifolds does not look to be a good start, so I think I will get the inlet manifold machined so the mounting flange is the same thickness as the exhaust manifold flange as well as getting some new studs and washers to replace what I currently have. I also found that the exhaust gasket had a leak underneath the car so new gaskets and sealant for everyone, yaaaay!

 

Peering into the ports and looking at the valve stems there doesn't seem to be any obvious signs of oil getting past the stem seals which is a plus, but I will clean the exhaust ports up and see what we have lying under all the carbon build up.

[C.A.R.]

When you put new washers on Alex, just put a dob of weld onto one side of the large flat washer to take up the difference in flange thickness (a stick (Arc) welder is fine for this job).

 

Getting the flanges machined is a real & expensive PITA...

[Agno]

So a little update, I added a fuel pressure reg (nice Italian made Malpassi unit) and set the pressure to 3psi, the Pierburg fuel pump was free flowing at about 6psi at idle. That fixed the plug fouling issues but made the car run lean and still not rev out properly.

 

After much stuffing about, I ended up taking Lurch's advice:

Take it down to Les Collins & get him to tune it.

 

If it's not the tune, I guarantee he'll find the issues(s) with it.

 

The car went to Pete and Les a couple of weeks ago and stayed there for 2 weeks worth of R&R. Now that the car is safe and sound in my garage I can tell you that these guys are magicians, I gave them a 3 legged stray cat and they turned it into a cheetah, the car is a rocket! I cannot thank Pete and Les enough for the work they did, it was truly top notch.

 

After getting the car back on Thursday, I had to get the car ready for a day at Haunted Hills hillclimb on Saturday. In the time I had I managed to squeeze in a day of uni, 2 work shifts and some (but not all) the zed work I wanted to do. 40 very short hours later I was sitting in the marshalling area:

 

Someone once told me that old cars are terrible except for the 3 days a year they work well, Saturday was one of those good days I think. Aside from being a bit wet, the car was magic and I had a blast on track!

 

At the end of the day I came 5th fastest on the clockwise layout and 6th fastest on the figure 8 with times of 66.96 and 70.97 respectively and edging out some pretty serious looking machinery in the process. I'm heading to Winton on the 2nd of June for some sprints and with the car set up the way it is I'm looking forward to comparing times with the rest of you guys in the lap time thread!

 

I also took the old spoiler off, it didn't want to come off without a fight...

 

Nothing a bit of paint couldn't fix. I had a change of heart with the Alfa fibreglass spoiler and am now either going wingless or using a Topstage wing I got from Retro-Z, I'll decide later.

 

I also really need to change the rear hatch seal (again!), as it's pretty obvious that the current seal (which is 12 months old) is doing an awful job at keeping the water out.

 

Bring on Winton!

[adam]

Awesome stuff mate. I just got my car painted white and I look forward to doing battles with you on track

 

Two white Zs head to head!

 

All the best with Winton.

[C.A.R.]

Good stuff Alex!

Craig was pulling his hair out trying to tune those horrible Dellorto's though!

 

P.S. You need to do something about the rust issues soon...

[peter mc]

ALL GOOD STUFF ALEX 

We all had a go trying to get them right LES was going mad trying then Craig had a go and then me then les then steve , haha in the end we got it right , there just dam hard to tune ,

[Riceburner]

Hows haunted hills Alex? I've never done that event.

 

I might be down for winton too, it's a good track but so bloody far away.

[Agno]

HH is a great track. It's very technical and it's not like your typical racetrack because there isn't really much time to think before the next corner hits you. Also quite a few of the corners are blind so it means you have to be a bit brave when chasing a fast time.

 

I think Winton will probably be the track I visit most often in the future as a lot of my mates do sprints there plus I don't really have the funds (or cojones) to tackle PI or Sandown on a regular basis.

[luvemfast]

HH is a great track. It's very technical and it's not like your typical racetrack because there isn't really much time to think before the next corner hits you. Also quite a few of the corners are blind so it means you have to be a bit brave when chasing a fast time.

 

I think Winton will probably be the track I visit most often in the future as a lot of my mates do sprints there plus I don't really have the funds (or cojones) to tackle PI or Sandown on a regular basis.

Sooooooo..........

I read that as you.

And your mates are poor.............

With small balls!

 

You're right about HH. Technical, fast and blind.

I love it. 

[Agno]

Oh Simon.... 

 

I can't speak for the financial stability of my comrades but they definitely enjoy the finer things in life such a PI sprints and "track day rims". That is the dream one day, for now I'll be happy just to get out when I can!

 

I should have just bought a Skyline/Evo and gone faster for less money, but then I wouldn't look so damn good while I'm doing it! 

[peter mc]

anyone can go fast in a skyline or evo , only cool cats go fast in zeds

[Agno]

I was going to write a big write up of the weekend past at Winton, but I really can't be bothered! For my first time out at Winton I managed a 1:47.8. While that isn't too bad in reality I'm a bit disappointed as I would have really liked to have been about another second or so faster than that. With practise I think that is definitely achievable though.

 

Also now I have taken the car out for a few events I have been thinking about the setup. Currently with the suspension setup it has the car really pitches and rolls quite badly around corners. Which isn't too bad but it also understeers quite badly when being driven hard. Something that Pete and Les also picked up on when they had the car tuning, not sure why considering they should only have been testing the car for drivability in a straight line!

 

The coilover collars were welded on the struts in such a way that while there is plenty of travel at the rear end of the car but the fronts bottom out very easily at the current ride height, which is probably the main cause of the understeer. Given raising the ride height for more travel is not an option (I like it this low) I will be sourcing some new struts and redoing them so there is more suspension travel even when the car is lowered. It would also be nice to stiffen everything up a bit but one step at a time I think.

 

Some pics:

Snapped the key the night before Winton, it's a good thing I never actually went and got the key cut like I said I was going to.

 

Also at some point in the 3rd session of the day one of my C pillar badges fell off. I'm pretty annoyed because I really like the way they look on the car. I'm sure they don't look quite as good on the Winton infield somewhere! If anyone has a pair of badges laying about PM me, they don't have to be perfect because I liked how the old ones were a bit rough, it matched the car overall.

 

... and just some other random photos I snapped on the day:

 

 

 

This spells the end of a busy period for the Zed, after this weekend it is being parked up for a while and getting some well deserved TLC. Nothing major but just some little things I have been ignoring while fiddling with the carbs and junk. I have my list of things to do and hopefully once I get some spare time I can start crossing them off!

[Zedman240®]

As far as I'm concerned, if you can still drive the car home after 3 good runs, its a great day! Losing parts is standard; last time at Winton I lost one of my trumpets with a uni filter still mounted on it..luckily a flaggie spotted it and luckily no one else ran it over.