spark plugs with stock heads and E85

[gn.87]

What plugs should I get tonight? I was told to get NGK UR-5s and gap about 32. Anybody want to confirm this is a good direction or have other suggestions. I will set the boost to about 25lbs.

 

[Boost231]

AR133

 

[Roc87]

I've had great luck with the NGK UR5's on stock heads using alky, so I'm planning to use NGK UR6's (7773) for stock ported heads and E85.

Have also heard the AR133's are good, so I may try those too

 

[Eric Stage I]

Stick with a resistor plug or it may bite you later. I prefer the NGK UR5 or UR6.

 

[czimpel]

I'm running the UR5 in my Champion irons on E85. Running at least 25#s.

 

[gn.87]

Thanks Eric.

 

[Roc87]

What plugs should I get tonight? I was told to get NGK UR-5s and gap about 32. Anybody want to confirm this is a good direction or have other suggestions. I will set the boost to about 25lbs.

Do have the stock ignition system? May need to gap tighter than .030", when I was running the stock ignition & alky at 30# I had plugs gapped @ .028". With the TR6 I have them at .033" but haven't turned it up yet

 

[achalmersman]

Idk why people keep advising the AR133s on a stock ECM car with all the multiple threads on issues caused by non-resistor plugs. Listen to Eric on this one. Take it from one that got bit....

 

[turbo nasty]

Ngk racing 2817 Non resistor non ext reach cut back ground strap is a good plug with irons. But is a non resistor

 

[achalmersman]

NGK YR5 or YR6 is a non-projected tip plug and is resistor core.

I ask this sincerely not sarcastically, what is everyone's obsession with solid core racing plugs on everything even stock headed cars? Is it even possible they could gain 1/2 HP?

 

[turbo nasty]

Because...racecar

 

[Boost231]

Ar133 because the work fine in my car and others. Yes some have issues some dont. There are other choices out there but it's a option.

 

[achalmersman]

Yea but this is fact: nobody has ECM issues because of resistor core plugs. Period. Why suggest a plug that may lead to issues when there is an alternative that won't. I wish there hadn't been so many people suggesting AR133s on this forum when I went down this road. Would have saved me a month of headaches, swapping back and forth between 2 different chips, 2 different ecms, 3 different power loggers, 2 sets of wires, many many loaded voltage drop tests, etc

At the time I didn't even know they were solid core plugs. I know... Rookie mistake. My aftermarket experience is still growing...

 

[gn.87]

Yea but this is fact: nobody has ECM issues because of resistor core plugs. Period. Why suggest a plug that may lead to issues when there is an alternative that won't. I wish there hadn't been so many people suggesting AR133s on this forum when I went down this road. Would have saved me a month of headaches, swapping back and forth between 2 different chips, 2 different ecms, 3 different power loggers, 2 sets of wires, many many loaded voltage drop tests, etc

At the time I didn't even know they were solid core plugs. I know... Rookie mistake. My aftermarket experience is still growing...

Nice post. Well said.

 

[tsm3089]

NGK YR5 or YR6 is a non-projected tip plug and is resistor core.

I ask this sincerely not sarcastically, what is everyone's obsession with solid core racing plugs on everything even stock headed cars? Is it even possible they could gain 1/2 HP?

Heat range selection may have a lot to do with it,

 

[gn.87]

Do have the stock ignition system? May need to gap tighter than .030", when I was running the stock ignition & alky at 30# I had plugs gapped @ .028". With the TR6 I have them at .033" but haven't turned it up yet

so I should gap at .028- and not .032?

 

[turbo nasty]

NGK YR5 or YR6 is a non-projected tip plug and is resistor core.

I ask this sincerely not sarcastically, what is everyone's obsession with solid core racing plugs on everything even stock headed cars? Is it even possible they could gain 1/2 HP?

The Racing brand plugs from NGK have a different ceramic construction to help with arc leak from plug boot, Cut back ground strap and non projected tip. Of course the plugs you mentioned could work as well but a EFI and non resistors dont always jive.

FWIW I ran NGK racing non resitor 2817 with my irons for years and years and never had a issue. Not all can tho.

 

[Roc87]

so I should gap at .028- and not .032?

You may be able to run .032, just be aware at that boost level you'll most likely blow out the spark and have to close the gap to avoid it

 

[achalmersman]

The Racing brand plugs from NGK have a different ceramic construction to help with arc leak from plug boot, Cut back ground strap and non projected tip. Of course the plugs you mentioned could work as well but a EFI and non resistors dont always jive.

The plug I mentioned is resistor core.

 

[turboplow]

Well I don't know much about this but I can tell you what I use. Autolite racing AR135 and gap is at .028. Mildly ported stock heads. @ 25 lbs. It's working great for me