Spark Plugs for 500rwhp
 

I've heard of the snow mobile ones being used. Is there any performance difference between those and the greddy or hks plugs? I don't think I want to spend 35 for each plug but I have come this far so why not if I have to I will.
10 or 11 heatrange or what? and would I do that just for the leadings or both?

And where do I get whichever plug you've suggested for the best price. I do need them by Wednesday or so of this coming week.

Thanks team

Yanni

Run colder plugs. From what I've heard, the 7's I believe are the best plug for the Rx7 from NGK, don't know if you'll want to use those.

I am at 410 rwhp and my car does very nicely with BUR9EQP leading and BR10EIX trailings (gapped at 0.022).

At 500 rwhp, you might need to move to 10s in the leading and 11s in the trailing... but since I'm not there... I don't know :)

*edit* to install the BR10EIX, you need a thin walled plug socket. You can spend a bundle and BUY one, or you can just take a 2 dollar regular thick wall one and carefully grind the end to a slightly smaller diameter with a bench grinder.

sounds like a pain in the ass with the grinding

why would I do it for the trailings only?

what will happen if I try to get this hp with 4 bur9eqps?

Colder plugs are to avoid detonation, so if you used the hotter plug (9's vs 10's) you would run more risk of detonation, and wouldn't be able to turn the boost up as high.

-s-

There is a guy that sells the thin walled plug socket here on the forum. If you do a search in the for sale section for socket you'll probably find him....look for old posts like over a year old. I think he goes my metalman. Seems like its $20 shipped.

I'd either tun the B10egv plug all the way around or maybe B11egv depending on what kind of fuel and how much boost this is going to take. The B10egv makes an excellent street plug, mine never fouled. Dont know how the 11's will do in a street car thats actually driven around town a lot. If I had to guess I'd say they are probably ok since the 10's last so long.

I know of some people using HKS 11 and 12 for 400-500 HP

Don't laugh but I have a 62-1 Turbo with a 1.00 devided exhaust housing. I was told I might be able to get to my goal of 500rw adn that 475 should be pretty attainable.


That guy is just selling the sockets I need to know where to get whatever plugs I need. What plugs exactly do I need and from where??

Here are my engine mods so you can see fuel:

1994 RX-7 53k Miles
New Ported Engine 2mm 2 piece Mazda Seals - 62-1 Turbo 1.00 Divided- HKS SS Divided Manifold - HKS 50mm Racing Wastegate - HKS SSQV BOV - Modified Greddy 3 Row FMIC - Apexi PFC + Commander + Datalogit - New # GM 3 Bar Map Sensor + Connector - 50/50 Water/Alcohol Injection - Custom Spec Clutch with M2 Lightened Flywheel - 1680cc Secondary Injectors - 850cc Primary Injectors - Aeromotive Fpr with VDO FP gauge - M2 Boshe Fuel Pump - Custom LIM - Crane Cams HI-6 Ignition - Magnecore 10mm Plug Wires - 4 BUR9EQs - Custom Air Intake - Custom Downpipe With Cutout - Midpipe With Borla XR-1 Muffler - Greddy SP Catback Exhaust - Greddy Pulley Kit - Greddy Profec B - PFS Boost Gauge - Pettit Aluminum AST - Relocated Battery - M2 Trailing Links - Gotham Racing SS Braided OMP lines - Koyo Radiator - Engine Tq Brace - Little bit of Polishing ; )

Use might use four NGK BUR9EQP's.

Mazdatrix sells that thin walled socket, as well, IIRC.

I am using 4 bur9eqps right now I dont think thats good enough

Anyone else?

yanni

The EGV and EIX plugs mentioned are available at motorcycle shops, the EGV are standard plugs and EIX are iridium. There are also platinum plugs of that style that would work, but platinum doesn't ignite as well or last as long as iridium.

I'm running EIX iridium plugs, 8's leading and 9's trailing in my car which is mostly stock w/ a downpipe. The 8's are fouling a bit too fast, I'll go back to 7's soon I think. I ground my own thin-wall socket, it took a LOT of grinding. A premade tool would probably be worth the $20.00 in the time and mess it saves.


edit: bought mine at www.chaparral-racing.com

I use NGK racing 6725-11.5 in my road race FC

I recommend running some kind of 'race plug' heat range. 9s all around definitely won't cut it at the boost levels needed to put down 500 rwhp. Over the years I have tried the NGK and Greddy plugs in 10, 10.5 and 11, predominantly in the leading but occasionally in all 4. Of course at like $30 each, it gets expensive, so I would usually just run leading. The 10s seemed to last longer than the 10.5s and 11s, but for a street car you will have to pull them and clean them every couple of weeks. Harbor freight sells a nifty spark plug cleaner, you just need an air compressor to go along with it. Will save you boatloads of cash by making the race plugs last much longer.

Right now I am running 9s all around at 12 psi and about 340 rwhp with no problems. Once I move up to 15 psi and above I plan on running race in the leading again.

The b10egv's that stephen (spo) mentions sound like a great idea for your (and my) application if they really don't foul out that quickly. That might be the best way to go.

Hopefully this link will work, the b10egv plugs are Only 5 bones each, cheaper than ngk 9s!

http://www.chaparral-racing.com/Chap...7DBAA1D68135AF

Actually, I am thinking of trying the br10eix's on this link:

http://www.chaparral-racing.com/Chap...7DBAA1D68135AF

and getting a thin wall spark plug socket from keith www.kgparts.com

I think that setup would work good for ya, yanni.

--Rich

rich why should I get that one over the bgv10 or whatever

According to NGK , the IX plugs are better all-around: won't foul as quickly, and produce a better spark.

http://www.ngksparkplugs.com/product...300&country=US
http://www.ngksparkplugs.com/product...420&country=US

However, according to their tech info, the 'standard' face used in the EGV and IX plugs might dissipate less heat than the 'rotary-specific' BUR7EQ plugs with the flat face, which is reportedly designed to reduce chances of flooding. The RX-8 comes equipped with a standard face 'OE Laser' NGK Iridium plug, but their engine does not produce as much heat as ours does, so that would be like comparing apples to oranges.

http://www.ngksparkplugs.com/techinfo/spark_plugs/

-s-

Hm, but heat range of 7 won't help modded FD guys. I'll prolly go with the b10egv's.

Rich thats what I ordered today

the b10egvs 18 for all 4 from advanced auto its 1/2 as cheap as stock

does anyone know what I have to gap these to? bryan at bnr told me to 32thousands

also can I just try to get these on finger tight and then grab it with plyers once and tighten it? or how much should I grind off of my spark plug socket? I dont know if I can find a laith or whatever here at school....what a pain in the ass I better make some power

If Bryan told you that gap, then I would run it. He knows his shit.

Re: the plug socket, just plunk down the 20 bones and buy one from keith at www.kgparts.com . You'll get a lot of use out of it ;)

yeah but that guy steve kan is coming friday for the tuning session I setup
when I ordered my fuel system I sometimes had a hard time reaching keith if I could get the socket by friday id order it but I know I wont

I've placed 3 time-sensitive orders with Keith over the last two years and he has delivered on time without a hitch. However, I did place the orders through Keith over the phone.

regardless of what you do, don't try the handtighten-and-pliers method. Those suckers will spin right out. There's a bit of pressure exerted on them ;)

I ground my own plug socket, bought a cheap one from the motorcycle parts store I found my plugs at, and ground it with a grinder. It took a while to get it to the needed thickness (or lack thereof) but it got the job done in the end.

If Steve Kan is coming to tune your car, you might be best off to buy a few different sets and heat ranges, and install whichever plug he recommends. Spark plugs are pretty quick like that.

-s-

Question: Do hotter plugs require a richer mix than a colder plug would? And what sort of HP limit is there if you run 4 7's? I'm not quite understanding all this.:scratch: