RV8: Side Gapping Plugs?
Discussion
Hardly a major mod but I wondered if anyone had experimented with the practice of 'side gapping' spark-plugs in the RV8. The theory being that the charge is exposed to an unshrouded spark, thereby making for improvements in combustion. If the theory is right then I can only foresee the down-side being a reduction in plug life.
Anyone? Joo?
Anyone? Joo?
That looks like the opposing electrodes just have less surface area to hit ..
I'm guessin here but I think it might promote mis firing under the worst conditions .. like a like lean cruise and light load .. so guaranteed plenty of pops and bangs.. melted catalists etc..
What I thought you meant was to ensure the plug was fitted in the head so that each open face of the plug actually faced down - so that it was always exposed to the mixture - now that would be beneficial but you would need more collapseable collars on the plugs and to mark the side of the plug to know it's in the right place.
Perhaps all racers do this any way ?
I'm guessin here but I think it might promote mis firing under the worst conditions .. like a like lean cruise and light load .. so guaranteed plenty of pops and bangs.. melted catalists etc..
What I thought you meant was to ensure the plug was fitted in the head so that each open face of the plug actually faced down - so that it was always exposed to the mixture - now that would be beneficial but you would need more collapseable collars on the plugs and to mark the side of the plug to know it's in the right place.
Perhaps all racers do this any way ?
Many years ago now, about 17........ I think.
I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
Ah, now that's electrode phasing Rev, which in itself is a different practice but which I understand is used to good effect in some combustion chambers. The plug can be shimmed, but to some degree that will affect the protrusion. Usually the plug ceramics are marked and various plugs are attempted until the desired electrode direction is achieved. Fine if you're a race team and have a motor on the bench; not so good for a limited budget and an installed Griffy lump.
With regard to your comments on side gapping: I guess the spark will take the shortest route and as that is likely to be across 'edges', then spark erosion would reduce the plug life. I dunno that it would in any way reduce the size of the spark though. It may have to be something I put to the test when I'm on the rollers next.
With regard to your comments on side gapping: I guess the spark will take the shortest route and as that is likely to be across 'edges', then spark erosion would reduce the plug life. I dunno that it would in any way reduce the size of the spark though. It may have to be something I put to the test when I'm on the rollers next.
Speed eight said:
Many years ago now, about 17........ I think.
I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
Ah, something of substance; Ta for that!I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
Bruce
2Munkys said:
Speed eight said:
Many years ago now, about 17........ I think.
I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
Ah, something of substance; Ta for that!I was developing a very powerful Ray Web 4.5Lt Rover engine.
The final set up was carried out in the chassis at Power Engineering at Uxbridge on the rollers there.
Amongst many things tried was the setting of plugs so that that the flame front was always pointing to the most advantageous part of the combustion chamber and also "side" gapping the plugs.
At the same time GKN where sponsoring me with plugs and many "new" types of plug where coming my way.
Exotic materials, needle points, "V" grooves etc.
All of these where tried.
Anyway the upshot of all this time and cost was sod all if any benefit.
There where no miss-fire issues or associated problems. At the same time though I was using a very high energy ignition system.
Possibly an MSD unit
A far better performance gain move would have been to remove a few pounds of weight from the vehicle.
At the same time as I was trying all this there was a chap doing exactly the same on a full house big block Chevrolet engine. Now he did achieve a measurable result. It was about a consistent 5 Bhp.
But you could argue that 5 Bhp increase could be down to atmospheric/machine/user/ any other thing that you can think of.
Regads,
Speed eight.
Bruce
BHP is great gain for a racer but if it does not last 6K on the road then the benefit of side gapping would not be worth while .. but the plug direction thing can't do any harm - might just try that one myself.
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