- Jan 28, 2006
- 158
My GT has a Kenne Bell "HCD" Snout w/ 2.75 pully. Makes 15" boost now vs 12.5" stock. Also has the Kenne Bell "Flash tuner", Kenne Bell Spark intensifier run at 110%, Kenne Bell recomended NGK TR6 plugs, Accufab air inlet support, Ford Motorsport (Borla) exhaust, & Ford motorsport transaxle cooler. I run on 93 octane pump gas.
Although I was not able to do a dyno run as the shop that did the work has a brake dyno that only goes up to 400 rwhp, The car absolutely had a very noticeable increase in power. It became downright violent (in a good way).
Recently I felt it may be down just a little on power and I thought I may have heard some detonation under full throttle. Most likely I was just getting used to the power and was being paranoid. Just to be sure, I did a leakdown test on my own and the results were very good (0% leakdown in the front six cylinders and 2% leakdown in the rear two). While doing the leakdown I was shocked to see that the ceramic insulators of the NGK TR6 plugs were as white as a sheet of paper. They definately looked lean / hot. I further noticed that the threads of the plugs went past the head. the last 2-3 threads on the end of the plugs had been exposed in the combustion chamber and were covered with carbon. The plugs were actually hard to remove. It seems to me that these plugs, although recomended by Kenne Bell, are not appropriate for this application. They are obviously too far into the combustion chamber and that could be responsible for the hot / lean appearance of the ceramic insulators. Further, having plug threads extend past the end of the head can damage the aluminum heads if too much carbon / crud builds up on them prior to removal.
Ideally I would like to install a couple heat range cooler version of the stock Ford plug. Does anyone know what that would be? Also what exactly is the stock plug? I no longer have them. Worst case, I will install a set of stock plugs and see what they look like after a while.
Although I was not able to do a dyno run as the shop that did the work has a brake dyno that only goes up to 400 rwhp, The car absolutely had a very noticeable increase in power. It became downright violent (in a good way).
Recently I felt it may be down just a little on power and I thought I may have heard some detonation under full throttle. Most likely I was just getting used to the power and was being paranoid. Just to be sure, I did a leakdown test on my own and the results were very good (0% leakdown in the front six cylinders and 2% leakdown in the rear two). While doing the leakdown I was shocked to see that the ceramic insulators of the NGK TR6 plugs were as white as a sheet of paper. They definately looked lean / hot. I further noticed that the threads of the plugs went past the head. the last 2-3 threads on the end of the plugs had been exposed in the combustion chamber and were covered with carbon. The plugs were actually hard to remove. It seems to me that these plugs, although recomended by Kenne Bell, are not appropriate for this application. They are obviously too far into the combustion chamber and that could be responsible for the hot / lean appearance of the ceramic insulators. Further, having plug threads extend past the end of the head can damage the aluminum heads if too much carbon / crud builds up on them prior to removal.
Ideally I would like to install a couple heat range cooler version of the stock Ford plug. Does anyone know what that would be? Also what exactly is the stock plug? I no longer have them. Worst case, I will install a set of stock plugs and see what they look like after a while.
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