Yep, he's right use BPRs if your running under 21-20psi if your running 22psi or more I suggest running BRs.

 

I got 4 BPR8ES already so going to try that first then switch over. I'm running 25psi on 93 gas with alky.

 

why are so many people using the copper plugs? I think are cars are supposed to only use iridium plugs.

 

I heard from an Evo owner to stick with the BPR. He got better 1/4 trap speed with "P".

The Projected type spark plugs runs 10~15ºC hotter and probably the 4G63 head was developed to run with "P" type since the stock are P.

My car with stock boost lost Hp after I went with one step colder spark plug, but I heard many good reviews about the 8 when running high boost pressure.

 

A projected type tip/less shrouded type of spark plug may make a little bit more power but is likely to also increase the likelihood of burning a hole in your piston in case of detonation. Generally turbo and race-prepped cars run non-projected plugs.

 

Thanks, good info, learn something new everyday.

I would have learned nothing if someone's reply to this thread was "Use the search button". In fact I bet it would take about an hour of searching to find the above fact.

 

I got a set of the br8es's and the popping/misfire is gone at 25 plus psi. The car doesnt feel as responive now, but thats probably just in my head

thanks again for all the replies

 

It's possible that the lesser shrouded plug gives an effect similar to advancing the ignition timing, which can also be expected if the gap is enlarged. If this is the case, one should be advised of this when switching from one type to another, as it may potentially cause a problem.

 

This is a misconception. The Head was not designed around the spark plug. Also the Stock plugs were meant to handle specific boost and cylinder pressures from the factory.
Once adjusting fctory setting ie. boost, A/F rpm etc. The dynamics of combustion have changed.
The colder plugs should only be used when 2-3 psi of boost is added to the factory max. So 23 psi would be the time to change them to a good copper plug with long life. BR8ES is that plug.

My 2 cents.

 

i just switched from the stock plugs to the br8es last night on the dyno and it helped to clean up my run. NO misfires now!

 

I just got a P0300 misfire code on my car this morning. I'm running BPRES right now and just got back from buying a new set, but I think I am gonna take them back and get the BR8ES.

I spike at 22 psi on pump gas and have a custom tune from DynoFlash. Would those be the better plug for me? If so, what should I gap them to?

Thanks

 

The reason that most of you are noticing a cleaner run, or my car now runs with no misfire, after switching to the BR from the BPR is because the plugs were simply fouled. I used to foul the BPR plugs after about 2-8 pulls. I would switch them with another set of BPR's and it would run fine for a short time again... the car drives normally even with the plugs 'fouled' and they look fine if you look at them. I now switched to the BR8ES and they do not foul NEARLY as quickly. I have ran about 40 pulls on these plugs and they are still not fouled.

I have never regapped the plugs either, they are pregapped at .28 or so and thats where I run them at. I have never had a problem with spark being blown out or ignition not keeping up. I would just buy em and toss em in (In fact thats what I do). I have run the car at 21psi on a GT35r all day and have done a few pulls at 29-30psi with this same gap. It works fine.

 

Oh, and most people dont honestly need to switch to a colder plug yet. If your still on the stock turbo running pump gas (Even probably with race gas) you probably dont need to switch them but I dont think it could hurt you either way. The colder the plug, the more they will foul. I dont think there is much else of a difference.

For stockish cars use BR7ES or BPR7ES
For larger turbo car or heavily modified use BR8ES
For really large turbo cars use BR9ES

 

Okay....but what do you consider a "stockish" car? I have basic intake, tbe, cams, fuel pump, and reflash.

 

Let's officially coin the term "stockish car" so from this point it will no longer be missused.

stockish car n syn STOCKLIKE an evo with mods that do not exceed any combination of mbc, mailed-in ecu, intake, exhaust, and bov, or has issues, whether mechanical, tuning, or mismatched rendering car stocklike.

In this case use BR7ES, if you add cams and/or alcohol inj, still use BR7ES, if your at about 340whp - try BR8ES, if your at 500+ WHP - try BR9ES.

Gap accordingly to boost - 22 psi gap to 0.26 then decrease gap as the psi increases

Thanks