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Which spark plugs?

onesickcrx

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Jun 3, 2007
Messages
1,076
Location
NY
I am running bpr6es and I get knock at anything above 14psi on NY shity pump gas. So what plugs do you guys run at say around 19psi? I am going to install bpr7es and bpr8es tonight see if there is any difference on knock issue with those plugs. I was just curious to see what you all run? I have c.o.p. if that makes a diffrence to your responses?
 

I run BP7ES gapped at .028 (for 17psi+) in most applications and don't have any issues.
 

JSchleim18

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Joined
Oct 16, 2006
Messages
4,801
Location
Long Island, NY
I don't understand how we have shitty pump gas when we can get 93 and some spots 100 /ubbthreads/images//graemlins/dunno.gif

+1 on the BPR7ES Plugs
 
Last edited:

CP

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Joined
Aug 30, 2004
Messages
8,938
Location
West Simsbury, CT
I use NGK BPR7ES gapped to .022-.025 at 23psi on 93 octane.
 

onesickcrx

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Jun 3, 2007
Messages
1,076
Location
NY
I am refering too the 10% ethonal in our fuel it sucks never had issues with any of my bikes or car intill the ethonal. Some states have 15% I feel for them. It eats the anisation off carb parts not that were carborated but just saying.

I'll try opening my gap back up to .025 I have had them from .018 to .028

At first I thought it was the air/fuel but its stays at 11.5 as boost ramps up then soon as it fully boosted stays at 11.2 so i doubt thats the problem
 

onesickcrx

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Jun 3, 2007
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1,076
Location
NY
base timing is set a 5 degrees it was at 0 but advancing or retarding didn't change the knock issue.
 

spooling92vr4

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Jun 7, 2005
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2,511
Location
long island, NY
California guys would probably stab someone in the neck to have 93 octane there. NY gas PRICES suck, but the gas is good.
 

atc250r

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Joined
Sep 11, 2003
Messages
13,235
Location
Orange County, NY
NY gas seems OK to me. I run 25psi on my 56trim with it all the time with no knock. It sounds like you may have some other issues going on.
 

1gnasty

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Joined
Aug 9, 2005
Messages
913
Location
garfield nj
Quote:
I am refering too the 10% ethonal in our fuel it sucks never had issues with any of my bikes or car intill the ethonal. Some states have 15% I feel for them. It eats the anisation off carb parts not that were carborated but just saying.

I'll try opening my gap back up to .025 I have had them from .018 to .028

At first I thought it was the air/fuel but its stays at 11.5 as boost ramps up then soon as it fully boosted stays at 11.2 so i doubt thats the problem


ethanol is the best thing ever i cant wait to we get e85 in our area,sounds like u have some tuning sues to me
 

atc250r

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Sep 11, 2003
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Location
Orange County, NY
10-15% Ethanol in our fuel is not a plus in the performance department since the octane of the fuel is still 93 and you need more injector to keep your AFR's in check if there is Ethanol mixed in. I'm looking forward to E85 getting here too but the crap that passes for pump gas now cannot be compared to it.

John
 

pachood_1953

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Joined
Sep 20, 2006
Messages
737
Location
eau claire, wi
Quote:
I run BP7ES gapped at .028 (for 17psi+) in most applications and don't have any issues.



Should I run 7es's (and what gap) on 9:1 w/ 93 and meth, at ~15-20 psi?
 

Yes, start with the BPR7ES and go from there. It's always best to only change one thing at a time, so only change one heat range at a time. Going to a too cold spark plug when it's unnecessary can be detrimental to performance. I'd start the gap at stock (which I think is 0.028) and adjust it down as necessary. You want the largest gap you can reliably run. A larger gap requires a more powerful spark to jump across it, which gives you a hotter spark and a much better source of ignition and will help keep the plug clean. However, at high boost levels there's just so much air and fuel between the electrode and ground strap that it can make sparking difficult, and that's when you need to start closing it a bit.
 

I have the iridium 8's in mine. the only detectable down side has been a small amount of poping cold, after about two min of run time they work great. then again not everybody wants to run ten buck a piece plugs.
 

Chief_Mak

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Joined
Nov 15, 2005
Messages
145
Location
San Diego/Oxnard
while we are on the topic of spark plugs, has anyone tried one of those plugstar plugs?? Supposedly, they can deliver 1 million watts of peak power.

click
 

GVR-4

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Joined
Apr 22, 2002
Messages
2,610
Location
Asheville, NC USA
Upon Ken Inn's suggestion, I have been running the Bosch WR7DTC plugs for a few years now and I like them. They have three straps surrounding the electrode and are "gapped" at ~.30". They have to be special ordered and are $5 each. The only time the spark gets blown out (16 psi) and the car stumbles is when they wear to the point that they need to be replaced, which is when I replace them. /ubbthreads/images//graemlins/wink.gif
 

My local CarQuest stocks BPR7ES's in the express pack (10 plugs) just for me. Apparantly I go through a lot of them.
 

Wizardawd

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Joined
Aug 7, 2007
Messages
1,323
Location
Franklin, NC
BPR6ES are stock....rule of thumb is +1 heat range for each 100hp.

And minus the P for Nitrous or high boost over 30psi.

IE: 400hp car at 25psi no Nos would be BPR8ES

This is just rule of thumb. Since parts combinations make a difference (wires, ignition, fuel, piston dish, etc.) it will be up to you to pick a number based on that rule of thumb and then tune and change from there.

Wiz
 
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