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Time for a service on my brothers R33, what oil and sparkplugs should we use and what is the gap best set at. I was thinking of using good old Mobile 1 to replace the $2 oil the importer would have put in it. It seems to have developed a slight intermitant stutter during heavy acceleration so changing the plugs would be a good start I recon.

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This must be the 1,000,000,000,000,000th time I have posted in re to spark plugs but I can't help myself.....

OK, when I bought my car, the guy I got it from put platinums (NGK platimun).... they took almost twice as long to foul as my coppers did. At 3 or 4 times the price, it doesn't seem worth it to me.

Then I put BCPR7ES, and the car felt great agin.... but they fouled VERY quickly on my car.... only mods were boost, cooler, cat back. It only took a few 1000 k's before the misfire at 5000rpm was getting worse.

Then I went for BCPR6E. Same as the 7's... felt great, but lasted a little longer before misfire got worse. However I would say the difference was negligable.

Then I went down one more to BCPR5E. These lasted me ages..... The misfire at 5000 rpm got considerably smaller than before. They worked a treat for me. So why the hell did I go back up to a heat range of 6???? Well I got a full turbo back xorst, and a SAFC, so I thought I should go 1 cooler, but it didn't help me.... :D

Overall, I have used a lot of different plugs, and my best experience was with NGK coppers: BCPR5E (oh, gapped at 0.75mm)

DennisRB30 - yeah i only got a 1psi increase, but it spikes to 10 occasionally. 9.5psi is a nice gain from 7 huh. maybe my gauge reads in the wrong place? coz the car has heaps more power after putting on the 3" pipe. my 33 is dead even with my mates 33 which has the same mods as mine but with the addition of a dsbc running 11psi on high....

-

Sorry Dennis, that wasn't me, it was Zahos. We use NGK BCPR7ES-11 gapped at 0.9 mm in the race GTST. When it starts missing I spend $18 and buy a new set. The road car gets PFR5A-11's gapped at 1 mm. I've not had any problems with this combo and they are cheap enough, so never bothered trying anything else.

Hope that helps.

Sorry for the mix up Zahos and Sydney kid. Anyway, the only ones I could find that matched any thing I was recommended were the same as BCPR5E (forgot the actual part number) but with a Y in the part number and are gapped to 1.1 mm instead of .8 The Y stands for a grooved electrode so I thought it wouldn't hurt (probably just a gymmick though). I gapped them to .9 and put them in. I found out what a prick it is to change plugs on a RB25DET!! I think the plugs that were in there were the platimum ones, the part number started with a P and the electrode tapered to a small point unlike a usual plug. They looked to be in perfect condition but were gapped to 1.1 which was probably causing the misfire not the plug itself. I was tempted to gap them down a bit and put them back, but I put the new ones in anyway because they were there.

I will post the part number of the plugs that came out and the plugs that I got when I have a look later on this week. We haven't has a chance to drive it yet since we are having a few probs with the stereo installation. But once the dash is back on, I will post the results of the new plugs. Hopefully the hesitation will be gone.

Originally posted by Sydneykid

The road car gets PFR5A-11's gapped at 1 mm.   I've not had any problems with this combo and they are cheap enough, so never bothered trying anything else.

Gapped at 1mm??? Gee thats pretty small....

Is that just a typo? If not, why such a small gap?

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