WanKeL FD RX-7

iTrader: (7)

Hi guys,

I want to make this short, but very accurate. I installed a new rebuilt motor last month in my car after blowing my new rebuilt installed in march 2007. Steve kan tuned my car which has streetported engine, GT3574 turbo kit, exhaust, fmic etc.. and one month after the tuning the engine blew because of bad timing. The timing was too hot in the higher rpms. So, there's a new engine in the car since august..

I made a good break in of the engine (2000KM, 1200 miles) without Boosting. I had chuck westbrook correct my original map from steve kan and I put it in my car last week. Made 10-12 pulls at 14psi and everything was going well, good AFR, good fuel pressure, consistant boost and knock level under control. Then 30 minutes later, it started misfire ... at high rpm, it miss power and makes a weird noise, I first thought of detonation but I tried it 5-6 pulls and made the same sound all the time so if it was detonation, basically, the engine would be gone already...

My idea is it will need some new spark plugs, i run 9's all around, maybe it's not enough, i ran greddy 10's when steve tuned it. My plugs were installed when we changed the engine, 1200miles ago.

For info, my leading coil pack is brand new from mazda, i have msd spark plug wires, and running 94 octane.

If u guys have any idea, let me know.

Max

cewrx7r1

iTrader: (2)

I am running B9EGV with stock ports, you need at lease a 10 range with your ported engine at the same boost levels.

You need to log the event (AFR, and ADVANCED function) and send me a zip copy.

Do you have an ignition amplifier?

WanKeL FD RX-7

iTrader: (7)

yes i have a twin power from hks.

i'll let you know about the log. thanks again buddy

WanKeL FD RX-7

iTrader: (7)

where can i find good spark plugs (10's) cheaper than the greddys which are 120$ usd for the set...

Max

GoodfellaFD3S

iTrader: (213)

www.sparkplugs.com, b10egvs

sk8world

iTrader: (5)

NGK Gold palladium 5927 B10EGV $5.74

is this it?

WanKeL FD RX-7

iTrader: (7)

yes just saw them, i'll also order the thin wall socket to be able to install them and wow, these plugs are cheap, thanks guys.

GoodfellaFD3S

iTrader: (213)

Keith Gibbons over at www.KGparts.com sells the thin wall socket.

WanKeL FD RX-7

iTrader: (7)

thanks rich hehe, i sent him an email to see if he can ship it fast.

93FD3S

Advanced Auto parts also has them for about $4.50 each. I'm gonna run the B10EGV for the trailing and a set of B9EGV for the leading.

Taz

iTrader: (1)

Just in case (and from experience) check your electric system. Load test your battery and check all grounds. Make sure your alternator isn't going bad. Good luck

MichaelB145

Sorry I know this post is a little old, but just found it....

From what I understand....the B10EGV plugs should be in leading and the B9EGV should be in the trailing. But I have also heard it both ways now. Can someone verify what the difference would be?


Also, I use the BUR9EQ for the trailing.....What difference would the B9EGV's make if any?

Viking War Hammer

iTrader: (8)

If I'm gonna run 10's, I run all 10's. If I decide to run 11's, I run all 11's.

classicauto

iTrader: (3)

Following the example set forth by Mazda, the leading position is a 7, trailing is a 9.

Therefore the hotter plug should go in the leading position if you choose to stagger the temperature ranges. I believe this is due to the fact that the trailing plug is exposed to a hotter eviroment when it ignites as it is essentially a "clean up" plug.

93FD3S

I've actually been running the B10EGVs in all four. Car runs great at 14#s low boost. I should also mention I'm running a TII coil, Jacobs FC1000, and Magnacor wires. I leaned out the water temp fuel settings on the PFC to smooth the idle.

rotaryinspired

iTrader: (3)

Run the cooler plug in the tailing position due to the fact that the spark plug hole where the spark fires is smaller than the leading, creating more heat.

afawaterpolo

iTrader: (7)

Regarding your question on the spark plugs the BUR9EQ is:

B- Thread diameter of 14mm
U - Surface or Semi-Surface Discharge Type
R - Resistor Type
9 - Heat range (2 hottest - 11 Coldest)
E - Thread reach of 19mm
Q - 4-Ground electrode

The B9EGV is:

B - Thread diameter of 14mm
9 - Heat range (2 hottest - 11 Coldest)
E - Thread reach of 19mm
G - Fine wire nickel alloy center electrode
V - Fine wire gold palladium center electrode

Before I get questions I am guessing the B9EGV plug uses a dual metal make-up for their center electrode, I'm guessing its a nickel alloy center coated with gold palladium. I found the info from NGK's website concering what each letter and number on the plug stands for.

As a side note, this is off NGK's website regarding the use of Resistor and non-resistor plugs. For the FD they recommend a resistor plug as standard for the following reasons:

NGK "R" or resistor spark plugs use a 5k ohm ceramic resistor in the spark plug to suppress ignition noise generated during sparking.

NGK strongly recommends using resistor spark plugs in any vehicle that uses on-board computer systems to monitor or control engine performance. This is because resistor spark plugs reduce electromagnetic interference with on-board electronics.

They are also recommended on any vehicle that has other on-board electronic systems such as engine-management computers, two-way radios, GPS systems, depth finders or whenever recommended by the manufacturer.

In fact, using a non-resistor plug in certain applications can actually cause the engine to suffer undesirable side effects such as an erratic idle, high-rpm misfire, engine run-on, power drop off at certain rpm levels and abnormal combustion.

xpherebeast

Have you checked your trailing ignition coils? I had a very similar problem. If it has a slight miss to it at a low idle (800-900) rpm but then cleans up through the rpm range until it burps. I would check your trailing coils. Possibly check your wiring under the front left tire to see if it has taken on damage, because the ignition wires run through that part of the harness.