Best spark plug for boost
Thread Starter
Instructor
Joined: Oct 2012
Posts: 193
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From: Glenolden Pennsylvania
Best spark plug for boost
Hey guys,
Need some advice. I have a 01 C5 with a blower cam, 243 heads, 921 springs and P1SC-1 procharger. Runs a max of 7.5lbs of boost and still has low compression like 10.5-1. Makes like 628rwhp.
What spark plugs are you guys using with a similar set up??
Need some advice. I have a 01 C5 with a blower cam, 243 heads, 921 springs and P1SC-1 procharger. Runs a max of 7.5lbs of boost and still has low compression like 10.5-1. Makes like 628rwhp.
What spark plugs are you guys using with a similar set up??
Le Mans Master
Joined: Jul 2010
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Nothing wrong at all what neutron82 suggested. But before i knew the ins and out about building a FI engine.
Because i been building engines since the 80's for myself and my friends which were NA engines. My first build FI 13lbs
boost high 600's hp i ran the stock plugs with no problems.
Because i been building engines since the 80's for myself and my friends which were NA engines. My first build FI 13lbs
boost high 600's hp i ran the stock plugs with no problems.
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From: Fort Wayne IN
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Could use a non-projected tip BR6EF gapped appropriately also. Could give a bit more of a safety net.
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.022??... seems a bit tight, no?
I didn't know they made a br6ef, this would be a good choice also and I would probably run that over the tr6... when I had issues with the tr6 I went to a br7ef... the non projected tip will prevent the insulator from essentially becoming a glow plug and prematurely igniting the air/fuel mixture
I didn't know they made a br6ef, this would be a good choice also and I would probably run that over the tr6... when I had issues with the tr6 I went to a br7ef... the non projected tip will prevent the insulator from essentially becoming a glow plug and prematurely igniting the air/fuel mixture
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Melting Slicks
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Le Mans Master
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I'm not knocking you at all. I'm just giving my experience with gapping plugs. I was 30lbs boost with .26 to .28ish but turned it down to 25 ish of boost to try and save tires. Guess how that worked out.
Melting Slicks
Joined: Nov 2013
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From: USA
TR6 @ 0.035" at around 700whp level... working great. Maybe I would look at TR7 or those non-projected ones if I were going to a race type event or something just to be on the safe side with regards to heat/pre-ignition.
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the tr6 did work good for me until I switched to e85, they started breaking up bad... I switched to br7ef and gapped at .030 and that fixed the issue... at the op's power level the tr6 would be perfectly fine or the br6 is worth a look imo
Melting Slicks
Joined: Nov 2013
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From: USA
I was under the impression for years that ethanol "burned cooler" and thus didn't require as cold of a spark plug. But about a month ago I did a deep dive into it and seems like it's actually kind of the opposite. Ethanol is more likely to pre ignite and if anything should run even colder spark plugs. Downside is of course they foul up faster. But With this $2 spark plugs....hardly anything gripe about. On my other cars, the norm is $40 ngk race plugs.... $40 each!
Melting Slicks
Joined: Nov 2013
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From: USA
It's my understanding that spark plugs really do not affect knock or detonation. The gap needs to be such that you don't get spark blowout under load (close the gap if you do). And heat range to avoid pre-ignition (air charge ignites before spark plug fires, very bad).... driving style also has a big impact on heat range selection.
Iridiums are fine and what all modern engines come with...if anything some of these newer cars are even more demanding because they are pushing so much power per cylinder / per liter. For example my 2.0T is over 400hp so over 200hp per liter. You just have to be careful gapping iridiums because the electrode is so small and more fragile. I try to find plugs that are close to my end state desired gap so I don't have to touch it or adjust much.
In the iridium lineup there is NGK TR6IX and TR7IX
Iridiums are fine and what all modern engines come with...if anything some of these newer cars are even more demanding because they are pushing so much power per cylinder / per liter. For example my 2.0T is over 400hp so over 200hp per liter. You just have to be careful gapping iridiums because the electrode is so small and more fragile. I try to find plugs that are close to my end state desired gap so I don't have to touch it or adjust much.
In the iridium lineup there is NGK TR6IX and TR7IX
Race Director
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From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
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2017 C5 of the Year Finalist
2016 C5 of the Year Finalist
2015 C5 of the Year Finalist
It's my understanding that spark plugs really do not affect knock or detonation. The gap needs to be such that you don't get spark blowout under load (close the gap if you do). And heat range to avoid pre-ignition (air charge ignites before spark plug fires, very bad).... driving style also has a big impact on heat range selection.
Iridiums are fine and what all modern engines come with...if anything some of these newer cars are even more demanding because they are pushing so much power per cylinder / per liter. For example my 2.0T is over 400hp so over 200hp per liter. You just have to be careful gapping iridiums because the electrode is so small and more fragile. I try to find plugs that are close to my end state desired gap so I don't have to touch it or adjust much.
In the iridium lineup there is NGK TR6IX and TR7IX
Iridiums are fine and what all modern engines come with...if anything some of these newer cars are even more demanding because they are pushing so much power per cylinder / per liter. For example my 2.0T is over 400hp so over 200hp per liter. You just have to be careful gapping iridiums because the electrode is so small and more fragile. I try to find plugs that are close to my end state desired gap so I don't have to touch it or adjust much.
In the iridium lineup there is NGK TR6IX and TR7IX
Find the heat range acceptable for the top end of the power and on the car, stick with that heat range only, and deal with changing plugs a little more often.