Ever see this issue with Cometic head gaskets??
- Thread starter gnfanatic
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Pronto
No amount of evidence will ever persuade an idiot.
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NGK are a nice plug.
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- May 28, 2001
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What we use in the GM LS type apps. Especially the turbo cars.
Mild turbo a 7. Crazier boost levels 8, 9, 10
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I've posted for many years now on the use of non-projectile plugs in both iron and al heads when in search of more power.
Inmo it's a very important peice of the power puzzle.
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- May 25, 2001
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I prefer this from motion raceworks
You can run it on the feed line and know the fuel going in to the engine, not after.
BEATAV8
The Engine Whisperer
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Champion aluminum heads? The NGK 5430 is an excellent plug. Gasketed, .708” reach, resistor, non projected. Get it on eBay, I buy several sets at a time. Brisk is also excellent just more expensive. Brisk DR12S or DR10S.
A drop of oil on the threads is sufficient.
A drop of oil on the threads is sufficient.
I use brisk and order direct
TIMINATOR
Well-Known Member
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A LIGHT coat of never sieze, and NONE on the gasket surface nor the last thread or so at the chamber end. If never size is in the chamber or the last thread to it, it will vaporize, and can deposit itself on the insulator causing a high boost/load misfire. I've seen peeps chase their tail trying to find the cause of that!
Also, side gap the plugs and index them! This allows a faster burn with less timing. That's a big deal, especially with alky.
I was so fixated at the projected nose with a too hot heat range plug to even notice the excess of never sieze...
BTW, what ign box and wires are you using with the distributor?
Now the head gasket issue is coming into focus!
TIMINATOR
Also, side gap the plugs and index them! This allows a faster burn with less timing. That's a big deal, especially with alky.
I was so fixated at the projected nose with a too hot heat range plug to even notice the excess of never sieze...
BTW, what ign box and wires are you using with the distributor?
Now the head gasket issue is coming into focus!
TIMINATOR
BEATAV8
The Engine Whisperer
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Yep the 5430 is a British item. Land Rover or something…. Sometimes it takes 6 weeks for shipping but they do always come. I end up selling them to my buddies because nobody around here has them locally. Brisk is easy to get through summit
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Which brisk #?? Never even heard of this company
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A bit more "G2" on the condition of the system.
First pic is as received flow. Baskets were clean. Flowed on "auto" with a time of 30 seconds. The values are in Mil liters or CC, your choice. That's a flow range from 3ms@600 to 3ms@10,000 rpm. There are steps in between that are wider pw than 3, and different rpms.
Both pics were flowed at the same pressure setting.
The 2nd pic is after 25 minutes in a heated 110*F cleaning system. As shown, a significant increase after cleaning.
These injs were bought @ Summit.
My conclusion is the set was not flow matched when sold.
I've not seen the tune. However, some corrections may have been made with the individual cyl features.
First pic is as received flow. Baskets were clean. Flowed on "auto" with a time of 30 seconds. The values are in Mil liters or CC, your choice. That's a flow range from 3ms@600 to 3ms@10,000 rpm. There are steps in between that are wider pw than 3, and different rpms.
Both pics were flowed at the same pressure setting.
The 2nd pic is after 25 minutes in a heated 110*F cleaning system. As shown, a significant increase after cleaning.
These injs were bought @ Summit.
My conclusion is the set was not flow matched when sold.
I've not seen the tune. However, some corrections may have been made with the individual cyl features.
TIMINATOR
Well-Known Member
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The Buick specified replacement plug is about 3/4 or more up the heat range of the hottest plug Champion (my favorite) makes, and plug is a very projected nose design. This was spec'ed because these cars were originally sold with low boost capabilities, and were among the fastest cars available in 1987 anyway.
The factory understood that most of these cars would end up in the hands of "posers," and were owned for the "status" and were likely never to be raced, so a hot plug was needed to keep them from fouling, which was a much more likely scenario given the "posers" mild driving habits.
Now, 36 years later, most TRs are in the hands of enthusiasts, and modified or heavily modified and that changes the spark plug requirements drastically, and darn near everything else. Very few of these cars are still "stock", so spark plugs are among the first things that needs to be addressed in a higher boost scenario.
Projected nose spark plugs are great for power in a N/A app, as well as smog law compliance. Neither of which is relevent to us.
TIMINATOR
The factory understood that most of these cars would end up in the hands of "posers," and were owned for the "status" and were likely never to be raced, so a hot plug was needed to keep them from fouling, which was a much more likely scenario given the "posers" mild driving habits.
Now, 36 years later, most TRs are in the hands of enthusiasts, and modified or heavily modified and that changes the spark plug requirements drastically, and darn near everything else. Very few of these cars are still "stock", so spark plugs are among the first things that needs to be addressed in a higher boost scenario.
Projected nose spark plugs are great for power in a N/A app, as well as smog law compliance. Neither of which is relevent to us.
TIMINATOR
TIMINATOR
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Your MSD setup was on my list of things to try, but I was going to incorporate a knock retard feature in my plans.
At this point I believe you now know what you need to address, in no particular order:
Machine work
Knock retard
Spark plug design and heat range
Matched injectors
Following Cometics instructions
Start there, the "brain trust" will, I'm sure, add more to the list.
TIMINATOR
At this point I believe you now know what you need to address, in no particular order:
Machine work
Knock retard
Spark plug design and heat range
Matched injectors
Following Cometics instructions
Start there, the "brain trust" will, I'm sure, add more to the list.
TIMINATOR
Yes, thanks to you guys. Much appreciated!! I am ordering the Brisk dr12s plugs, valves ,seals and guides are coming in from Champion this Wed, I guess I am going to stick with new 120 lb injectors, Unless I should go to 160??? I have a -8 feed, -6 return and racetronix double pumper setup
That spread is trouble in pic 1
When you cleaned them did you find anything in them like material?
