John Dixon

Cheers James Knew someone would bring up plugs!! This was an intermittant thing before I did the plug change. Thought it might be an injector connector so cleaned them, but symptoms are PTU to be honest. Be great if I can borrow it.

Anyone got a PTU I can borrow to prove it as the cause of a problem on my car ? Cheers

The 6 puck should easily take 450bhp. It's rated to >450ft.ibs as I remember

Just thought I'd give it a try. From speaking to alot of people who are very knowlegable on this sort of thing (people who build proper race engines) 99% of what's said about spark plugs is rubbish. OK plats/irridiums last longer and give more concentrated spark but that's it. It's fine to say irridium resists temp more etc. but how much of the plugs is actually irridium? A tiny part right at the end of the electrode. Other than that small part, the plug construction is identical!! Worst case here is that the plugs won't last long, or will foul up because they're too cold. I tend to do compression test every time I service anyway, so I'm taking the plugs out.

Wasn't a case of trying to save money, just couldn't get a platinum or iridium plug of the right dimensions in 7 heat range. PFR6B-11B now discontinued, NGK irridiums are too short. Not looked into HKS. These plugs are what some of the big US and Jap tuners recommend. Closed down to 0.8mm so the spark can form at high boost. Larger electrode surface area than plats so need smaller gap with same spark energy. Can probably play with the dwell/charge settings in the ECU but haven't tried it.

Changed a set of PFR6B-11C for ZFR7F-11 today. ZFR are copper plugs, so probably change them every time I do the oil but for £2 each, who cares? For comparison, both plugs are 11.5 mm from base of threads to the top of the metal 'shroud' around the insulator. ZFR are 2mm longer from top of shroud to top of firing electrode. Think length wise this puts them between PFR6B-11C and PFR6B-11B. The plugs I took out had definately overheated (insulator v. white and no deposits at all, electrodes glazed) so it's probably worth going up to 7's. Seems to be running OK on 0.8mm gap, but didn't go for a long run because I left the oil cap off!!!

FFS, sorry to hear about that Andy hope you're both OK.

I've got the 6puck on mine, and it's not too bad for every day use. Engagament is pretty harsh but OK when you get used to it. Also gotta be careful on downshifts, best to heel & toe or you can lock up the rears if you bang it down at high revs. No sign of slip, but I'm only running stock turbos.

This thread has started me thinking! I have a top end power loss too. Power went from 314@wheels to 285@wheels on the same RR when i thought it'd lost some punch. Curve is totally flat from 5500rpm up. Had thought plugs initially, but now wondering if it's VTC related. I think I'll try connecting a meter across them when driving, and see if it changes at the expected point. I'll let you know what I find out. Do manuals have a neutral switch BTW?

There is one byte in the ECU that controls the VTC. From my understanding, it's the point where the ECU stops the advancement of the timing on the inlet cam. On stock this is 5500rpm. Not that that's any help with the problem!

Does it sound like it's running on 5 cyls? Could be a dodgy injector connector. One of mine's a bit dodgy and it does that occasionally, usually just need a clean.

I've just ordered a set of ZFR7F-11 coppers to try in mine for now. Part of the reason irridiums are better is because the narrower diameter electroder provides a stronger spark, so the spark is strong enough to cross the gap in a dense (high boost) charge. The problem I'm thinking is if they're still 6 heat range you're going to be prone to detonation due to the electrode tips being too hot (the PFR6B-11C's I've got in now show strong signs of overheating). Also, I believe the length of these plugs is the closest to PFR6B-11B you can get I'll post the measurements vs PFR6B-11C for comparison when I've got them. Think I'll have to close the gap down on these - was going to start at 0.8mm - any ideas anyone?? I know some US tuners use PFR6B-11B as a colder plug, but remember their standard plugs are a 5 heat rating (fuel quality???) The japs seem to recommend the ZFR7F

Anyone got an EPROM eraser, and wouldn't mind erasing a few for me? Been farting around with maps and programmed all the blanks I have. Cheers

Warren, they're 330mm. Not too sure of the make, but they're japanese. There's a pic of them in my rides page.

Johnny at GPS, got 8 groove disks on mine and they're fine. Much cheaper than anywhere else I found.

Bloody 'ell, opened a can of worms here alright! All I'm getting at is that the AFR does nothing except change the MAF signal going to the ECU, thus shifting the ECU fuel enrichment value to a higher load point on the map. If you know how much it enriches by then you can change the map to the same value that the AFM fools it into giving. Also, the AFR can't extend the maps, so unless SE did it, once you go past the last load point (about 13psi) then the ECU will always attempt to make the same AFR no matter what signal you give it - probably why you see midrange gains and not too much at top end. Not saying it's not handy for tweaking in real time, but is usually set then left alone, which gains you nothing over a correct map. I'm not surprised you can make gains over an SE chip if it's mapped on the road as I've heard, you just can't get it right that way. It took about 4hrs solid on a rolling road to map my 205 properly.

Was thinking about getting one of these as well, but there's nothing it can do that you can't do with an Eprom programmer and some knowledge of the fuel maps. Works out much cheaper to do (£50ish). Added benefit is that you can play with the timing, set up for dual MAF etc. as well.

Anyone know what diameter the PCV hoses are ?

Johnny @ GPS. I just got 330mm skyline disks off him for my R34 callipars v. cheap compared to anyone else

Drove the factory red rose 4.5 Cerbera last year, and have to say it was awsome. OK in a straight line it didn't feel that much faster than the Z, but it was deceptive, if you looked at the speedo it was MUCH faster. All in though it was in a completely different league. Steering was perfect and it handled far better. The brakes were unbelievable. Much as I love my Z, I'm saving for a Cerb.

Just had to share that with someone because I was so chuffed :D Did sound absolutely awsome when it was opened up though (could hear it very well 2 feet off his bumper). Road was wide & twisty but he couldn't leave me at all between the bends. To be fair though, I was carrying a bit more momentum out of them - he wasn't the most commited round the twisties. Wouldn't even speak though when we stopped at garage.

Does anyone have any binary files for chips that I could have a look at ? Probably going to start playing with mine, so would like some for comparison.

I've got an ACT paddle clutch, and to be honest it's OK when you get used to it. Bit of judder in first but other than that it's fine.

I had this when I first got mine. Turned out the rubber boot at the bottom of the gear stick was not seated properly, so it didn't cover the hole in the floor when the stick was forward, but did when it was back. Amazing how much noise it actually stops! Was relieved as hell when I found out that's all it was.

I've got the uniroyles on mine too. I'm v. impressed with them. Grip in the wet is amazing compared to other tyres I've tried. Wouldn't bother with the nankangs, I had them on my old rover and they were crap even compared to the cheapies I replaced them with