FZRSupport: the FZROnline Archive

Anybody have any ideas on the best sparkplugs for an 88 fzr400 1wg? Irridium? The bike is race only, so WOT most of the time. Running 32mm flatslides and K&N pods, does that matter? Does porting matter? Looking for most power, not longest life/best mileage.

Thanks!

As long as they ignite the fuel/air mix, NO plug will produce more power than another.

This WILL be debated. But, I am convinced by the real research that has been done (and I have read a lot-we're talking back to back fully instrumented load cell dyno research.

There is ONE caveat......a plug that occupies more physical space in the combustion chamber will reduce volume, thereby increasing compression...this is the ONLY exception.

I'll disagree slightly - fancy plugs can make up for a weak ignition system, or avoid fouling in an over-fuelling environment (out-of-tune carbs, bad float bowl valves). That said, a fully-functional ignition and fuel system shouldn't see any real difference.

I've always snickered at these ads / websites for the "nuclear-powered" spark plugs - they replace plugs and very often plug wires on 10-30-yo vehicles, and Jeebus-be-praised the power & mileage improves! It's interesting to note that - as you mentioned - there are no back-to-back tests with Brand New OEM plugs & wires...

The plug on its own may not make any more power, but switching to a colder plug will allow you to run a more aggressive timing curve on a high compression engine, which will make power.

Same way as switching to flatslides isn't going to do add any power over the CV's unless you tune them for your engine. (or happen to get the right jet sizes in there from the get-go)

reelrazor wrote:As long as they ignite the fuel/air mix, NO plug will produce more power than another.

This WILL be debated. But, I am convinced by the real research that has been done (and I have read a lot-we're talking back to back fully instrumented load cell dyno research.

There is ONE caveat......a plug that occupies more physical space in the combustion chamber will reduce volume, thereby increasing compression...this is the ONLY exception.

The benefits of needle point center electrodes is that in they do provide a constant ignition point in a harsh environment. I would say that in two strokes this is more noticeable than in Four strokes unless the carbs are way out of tune across the throttle response (they all are to a greater or lesser degree by the nature of carbs.)

It is interesting that most pro -tuners of race bikes still use indexing to get that precision of flame front (also helped by precious metal tips )

RR whilst a plug makes no extra horse power surely the reliabilty of firing or the lack thereof would effect power production. 4 cylinder making more power than 3 with a fourth working intermitantly (playing devils advocate )

markd wrote:Anybody have any ideas on the best sparkplugs for an 88 fzr400 1wg? Irridium? The bike is race only, so WOT most of the time. Running 32mm flatslides and K&N pods, does that matter? Does porting matter? Looking for most power, not longest life/best mileage.

Thanks!

All were knew that iridium and platinum plugs have long life. If You was used coil oil. According to me, 4303s autolite would be good for you. It would be work nice on it. I hope that You will chose best plug for your bike.

Hi mate, flatslides do seem to get more power out of the 400 I got an extra 5hp on the dyno when I put mine on. Best plugs for your bike being used for racing is NGK CR10EK they have twin electrodes, dont wast money on iridium they dont give you any more power.