Hey guy's, I've been using the B9EGV plug with great success. No more mis-fires at high rpm and 15psi.

A buddy of mine has been doing some searching and came across the NGK R5671A-9 . This is supposed to be the same "9" heat range. It has a 5/8 hex so it's easier to put in. It has a V electrode for a more exposed spark . Best of all they're only $1.69 each at my local autoparts store. They also have R5671A-10's and 11's too.

I think they were used on Ford's with aftermarket aluminum heads. I'm a little hesitant to be a guinea pig but can't really come up with a reason not to use them other than the porcelain is slightly smaller and my boots might not fit well.

Anyone have any experience with this plug.

Scott

 

Is the thread the same? Reach? You don't want to hit the rotor or have the spark down in the spark plug hole too far.

-Max

 

I have used this plug in a ser 4 engine with good results, we also use them in twin turbo big blocks as a replacement for b9es . Another plug you could look at is the champion c59A or c57A which are close to a ngk 9 and 10 heat range.

Chris

 

Yes, they are exactly same thread and "reach". Only concern I have is if there's ANY increased risk of pinging. Say for instance this "V" groove electrode gets a hot spot on one of the pointed v ears, etc.

I'm tuned 11.2-11.7/1 across the board but... well, you know.

Anyone actually used them on their turbo rotary?

Thanks, Scott

 

O.K. , i will make that a bit clearer, i have used them in a turbo rotary with good results, how do you think that v- groove will stack up against the thin electrode on a B9EGV ?

chris

 

i use B9EV, and B9EGV and they both worked great...they are designed as a race plug so i feel more comfortable using these in my motors, no complaints yet.... ask yourself this question; do i want to risk blowing my engine because i wanted to save money on sparkplugs? i have seen cheap sparkplugs break porcalin break ,crack and go into the engine!

 

i've had the electrode fall off a B9EGV just driving along the road...........................................


one in a million chance though, but i did have it

 

back from the dead, anyone else run these r5671a? any heat range with good results? what psi and power level.

I'm thinking of buying colder plugs, still have stocker bur7/9 and making 400hp@14psi no breakup but i think if I put colder plugs would be safer for future higher boost.

someone recommended me r5671a, anyone with experience?

 

Get those 7s out of ther pronto.

For the street you can run 9s in all four holes at that power level, but I wouldnt go any higher.

If you go for more power, move to the NGK/Greddy race plugs--- if you wanna play, you've gotta pay

I've torn down many motors in the last years with cracking around the spark plug boss on the inner surface of the rotor housings due to guys running warm plugs with high powered applications.

 

hey rich thanks for the advice, but what is your opinion on the r5671?

and also which ngk exactly is the greddy race plugs?

 

installed bur9 all 4

but still no one used the 5671?

 

last pic down:

http://www.rx7.com/store/rx7/fdignition.html

 

Reach on the stock plugs is 21.5 these are 19mm, so this would be the same reach as the EGVs correct?

 

The 5671 is the 19mm reach, like the EGV. Shorter than the proper 21.5.

The Greddy plug is the R7420, which is the iridium version of the platinum R6725.

 

One of the best are:

NGK R6725-9 through R6725-115, Mazda racing, fine wire platinum center and ground electrodes, 14mm thread, 21.5 mm/.846" reach, 13/16" hex, recessed tip, resistor. But some of you might not be able to afford the $35 price per each.
But they are worth it if you love power.

 

So Im almost ready to fire mine up... trying to dig up as much as I can... Im running 13b, E85, blow-thru carb. First trials Im looking to get to 15psi. Then looking to get up to 20-25 psi. A friend recommended running the br10eix plugs for up to 15 psi...I havent seen too many peeps mention this plug...any feedback is greatly appreciated. This is a drag only ride.

 

I used to use them, worked pretty dang great!