It really isn't worth the 2hp at best you might gain. Do back to back dyno runs and your engine will vary more than that.
Spark Plug Indexing...
Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
Spark Plug Indexing...
This is where you install the spark plugs so they uniformly have the grounding electrode away from the intake valve allowing the incoming air/fuel charge to face an unshielded, open gap of the spark plug on every cylinder.
Anybody doing this on the SBC? Is it worth bothering?
Anybody doing this on the SBC? Is it worth bothering?
Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
Racer
Joined: Apr 2010
Posts: 409
Likes: 1
From: New York
amazing the guy shows it going in and lineing up right what do you do when it doesnt line up right and your off you have to add a spacer and you dont need that socket just mark the open end on your socket and you know where it is open
Melting Slicks
Joined: Feb 2008
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From: Palm Beach
Melting Slicks
Joined: Mar 2002
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From: S.L.C. UT
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Are you serious - The video was just to help the OP understand how easy it is. Indexing washers are super inexpensive and may actually let you free up some unrealized power. New plugs that haven't been installed will let you can get ~ 1/2 to 3/4 of a turn on them before the washer is totally smashed flat from snug so chances are you only need apply about 4 indexing washers. Trial and error should take less than 5 extra minutes per plug. There are a 1,000 ways to skin a cat. I'm pretty sure the guy knows you don't need the socket with the magic widow that's shown in the video.
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Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
Spark plug indexing is the ignition equivalent of engine blueprinting - it's inexpensive and guarantees you did the absolute best job when installing the spark plugs.
A couple hp here and a couple hp there makes this enthusiast a happy camper.
Besides - if it was just only about driving it, I'd get a better car than a 16 year old Corvette
Rob
Last edited by chileverde; Jul 12, 2010 at 08:58 PM.
Race Director
Joined: Sep 2001
Posts: 14,665
Likes: 749
From: NEwhere Ohio
I do it on my heads/cam/ LT headers stock displacement, stock bottom end blown (8psi) lt1.
Why?
Not for horsepower but for detonation resistance. I need every little bit of safety I can get to not have a hotspot in my cylinder that could trash my stock bottom end w/ a single detonation event.
If I can keep that glowing hot electrode upwards towards the top of the chamber, with the open side angled slightly towards the exhaust valve (so the intake 'cools' down the ground strap) than thats what it takes for piece of mind at least!
To do this, I didnt use any indexing spacers. I went out and bought 16? or so NGK TR6's and tried them one at a time until my marks were lined up correctly (ie. open side of plug facing dowwards and slightly towards the exhaust valve). The thread cuts were random, so you have to mark and try a few spark plugs before you find one that will line up right. This was a tedious process, but actually long tube headers makes it easier than on stock manifolds.
Why?
Not for horsepower but for detonation resistance. I need every little bit of safety I can get to not have a hotspot in my cylinder that could trash my stock bottom end w/ a single detonation event.
If I can keep that glowing hot electrode upwards towards the top of the chamber, with the open side angled slightly towards the exhaust valve (so the intake 'cools' down the ground strap) than thats what it takes for piece of mind at least!
To do this, I didnt use any indexing spacers. I went out and bought 16? or so NGK TR6's and tried them one at a time until my marks were lined up correctly (ie. open side of plug facing dowwards and slightly towards the exhaust valve). The thread cuts were random, so you have to mark and try a few spark plugs before you find one that will line up right. This was a tedious process, but actually long tube headers makes it easier than on stock manifolds.
Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
I do it on my heads/cam/ LT headers stock displacement, stock bottom end blown (8psi) lt1.
Why?
Not for horsepower but for detonation resistance. I need every little bit of safety I can get to not have a hotspot in my cylinder that could trash my stock bottom end w/ a single detonation event.
If I can keep that glowing hot electrode upwards towards the top of the chamber, with the open side angled slightly towards the exhaust valve (so the intake 'cools' down the ground strap) than thats what it takes for piece of mind at least!
To do this, I didnt use any indexing spacers. I went out and bought 16? or so NGK TR6's and tried them one at a time until my marks were lined up correctly (ie. open side of plug facing dowwards and slightly towards the exhaust valve). The thread cuts were random, so you have to mark and try a few spark plugs before you find one that will line up right. This was a tedious process, but actually long tube headers makes it easier than on stock manifolds.
Why?
Not for horsepower but for detonation resistance. I need every little bit of safety I can get to not have a hotspot in my cylinder that could trash my stock bottom end w/ a single detonation event.
If I can keep that glowing hot electrode upwards towards the top of the chamber, with the open side angled slightly towards the exhaust valve (so the intake 'cools' down the ground strap) than thats what it takes for piece of mind at least!
To do this, I didnt use any indexing spacers. I went out and bought 16? or so NGK TR6's and tried them one at a time until my marks were lined up correctly (ie. open side of plug facing dowwards and slightly towards the exhaust valve). The thread cuts were random, so you have to mark and try a few spark plugs before you find one that will line up right. This was a tedious process, but actually long tube headers makes it easier than on stock manifolds.
In pursuit of perfection, I was thinking of putting a set of denso iridium IT16's ( the ones with the .04mm dia. center electrode), gapped at .050", and indexed to have opening toward the intake valve on my stock LT1 motor.
I think this will produce the strongest arc (increased gap) with the lowest voltage requirement (.04mm tip requires 5000 less volts to arc than a standard tip according to Denso), and still have some longevity because of the hardness of the iridium tip.
Rob
Race Director
Joined: Sep 2001
Posts: 14,665
Likes: 749
From: NEwhere Ohio
yep, indexing the plugs, using the one with the thinnest wire center electrode, and possibly dropping down a heat range (and adding .005" to the gap) will give maximum benefits, both in assuring no hot spots and producing a powerful arc across the electrode.
In pursuit of perfection, I was thinking of putting a set of denso iridium IT16's ( the ones with the .04mm dia. center electrode), gapped at .050", and indexed to have opening toward the intake valve on my stock LT1 motor.
I think this will produce the strongest arc (increased gap) with the lowest voltage requirement (.04mm tip requires 5000 less volts to arc than a standard tip according to Denso), and still have some longevity because of the hardness of the iridium tip.
Rob
In pursuit of perfection, I was thinking of putting a set of denso iridium IT16's ( the ones with the .04mm dia. center electrode), gapped at .050", and indexed to have opening toward the intake valve on my stock LT1 motor.
I think this will produce the strongest arc (increased gap) with the lowest voltage requirement (.04mm tip requires 5000 less volts to arc than a standard tip according to Denso), and still have some longevity because of the hardness of the iridium tip.
Rob
I had an o2 sensor fail, after I put in the hotcam, due to gasket maker material accidently getting into my intake and getting burned in the cylnders. It then deposited across one of my o2 sensors, killing it.
Well, then the car ran rich and this quickly fouled my plugs. This left me with a no-start condition. The only option for getting the car to start (even starter fluid wouldnt work) was to remove the fouled plugs and replace them. Also replaced my o2 sensor too.
Some other guys here have had the same issue. Iridium, platinum, etc. is just a gimmick.
Team Owner
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From: Riverside County Southern California
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I indexed my LT4. Heck, the engine was on an engine stand, couldn't be easier.
Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
I do not recommend iridium plugs. the electrodes are smaller and more easily fouled up - if you have a cam, arent using the optimal heat range plug, or have an o2 sensor fail.
I had an o2 sensor fail, after I put in the hotcam, due to gasket maker material accidently getting into my intake and getting burned in the cylnders. It then deposited across one of my o2 sensors, killing it.
Well, then the car ran rich and this quickly fouled my plugs. This left me with a no-start condition. The only option for getting the car to start (even starter fluid wouldnt work) was to remove the fouled plugs and replace them. Also replaced my o2 sensor too.
Some other guys here have had the same issue. Iridium, platinum, etc. is just a gimmick.
I had an o2 sensor fail, after I put in the hotcam, due to gasket maker material accidently getting into my intake and getting burned in the cylnders. It then deposited across one of my o2 sensors, killing it.
Well, then the car ran rich and this quickly fouled my plugs. This left me with a no-start condition. The only option for getting the car to start (even starter fluid wouldnt work) was to remove the fouled plugs and replace them. Also replaced my o2 sensor too.
Some other guys here have had the same issue. Iridium, platinum, etc. is just a gimmick.
In my case, don't plan on changing the heat range in my internally otherwise stock motor, but since the plug will have higher conductivity due to the wire thin electrode and the wear resistant iridium material, i don't see foul outs as a problem even if i up the gap by .005".
Besides if it does foul out, I'm looking at the wires impedance or the coil's output as the cause since by design it takes 5000 less volts to fire the plugs than a conventional plug.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
If you don't understand the reasoning why someone would do this or the benifit of a technique like this - don't bash it.
I'm not sure how much more time I can spend driving my car since I've already got over 250 K on it....and still have plenty of extra time to wrench on it doing similar "pointless power adding techniques that amount to nothing" your talking about.
Team Owner
Joined: Feb 2006
Posts: 23,137
Likes: 117
From: San Antonio Texas
Just out of curiosity, how much of a change in plug angle does one shim make? Do they make them in thicknesses that account for a change of angle in degrees that you need based on the torque applied, or do you just add them trial & error till you find the angle you want? Where to get them?
(This may be something we can apply to the kart engine to gain that wee bit out of the corners we're lacking now.)
(This may be something we can apply to the kart engine to gain that wee bit out of the corners we're lacking now.)
Thread Starter
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
Just out of curiosity, how much of a change in plug angle does one shim make? Do they make them in thicknesses that account for a change of angle in degrees that you need based on the torque applied, or do you just add them trial & error till you find the angle you want? Where to get them?
(This may be something we can apply to the kart engine to gain that wee bit out of the corners we're lacking now.)
(This may be something we can apply to the kart engine to gain that wee bit out of the corners we're lacking now.)
http://www.summitracing.com/parts/MOR-71900/
Instructor
Joined: Feb 2009
Posts: 191
Likes: 0
From: Woodstock IL
It's hard to believe this thread is still going. I wouldn't be disagreeing with all of you if I didn't have something to back up my argument. But yes, you are still splitting hairs on this issue. Read the article in Hot Rod magazine that I have attached. It states that "there's usually no discernible power difference". Also, have any of you taken into consideration that using indexing washers runs the risk of recessing the spark plug too far. This can lead to misfiring.
http://www.hotrod.com/pitstop/hrdp_1...ech/index.html
http://www.hotrod.com/pitstop/hrdp_1...ech/index.html