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In an effort to help answer the heated debate of whether or not the SVT's have a "flaw" because #3 fails due to a bad tune or just over time with FI... here's a theory from Jon Kuriyama (fastraxturbo). He's R&D for HKS and I can gaurantee there are few people if any on this board that know more than he does.

Here is his explanation of the issues with the #3 cylinder

Its not just Zetecs, but alot of 4 cylinders. I said something in the forced induction forum, and stated that it was not documented, or tested as fact.
It was theorized that more heat is retained in #3 cylinder because based on a standard 1-3-4-2 firing order, #3 fires and then #4 which is next to the cylinder, and then 2 which is also next to it. THe inner cylinders (2 and 3) usually run hotter anyway beacause of water jacket design. #2 also has adjacent cylinders that fire, and I have seen blown engines with detonation in both cylinders. Airflow distribution also has an affect, as well as fuel distribution. I have also seen motors with blown cylinders that are on the opposite end of the fuel rail feed.
Also the SVT does have hypereutic "cast" pistons... these are not made for FI. They have some advantages over just plain cast pistons, but none of these are to withstand heat. The are stronger and can hold tighter tolerances but they still act as "cast" pistons when it comes to heat and detonation. These are the first to go, we have yet to see an SVT rod fail at any time. It's always been the pistons.
 

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That's some good info ( especially to someone who is currently wieghing the options for FI )


has anyone determined a timeframe or noticed any sort of pattern to the problem?

I know that if your running higher PSI or drive your car "spirited" your more prone to the damage

but i do drive my focus 100+ miles per day back and forth to work so info liek this is priceless
 

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What types of EGT are others seeing, Mine reads between 1200 and 1400 when on the highway.
 

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I see about EGT's of 1200-1400* cruising on the freeway also. About 800-900 at idle I believe.
 

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I see about EGT's of 1200-1400* cruising on the freeway also. About 800-900 at idle I believe.
I have the same, what does a stock NA car run.
 

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In an effort to help answer the heated debate of whether or not the SVT's have a "flaw" because #3 fails due to a bad tune or just over time with FI... here's a theory from Jon Kuriyama (fastraxturbo). He's R&D for HKS and I can gaurantee there are few people if any on this board that know more than he does.

Here is his explanation of the issues with the #3 cylinder

Its not just Zetecs, but alot of 4 cylinders. I said something in the forced induction forum, and stated that it was not documented, or tested as fact.
It was theorized that more heat is retained in #3 cylinder because based on a standard 1-3-4-2 firing order, #3 fires and then #4 which is next to the cylinder, and then 2 which is also next to it. THe inner cylinders (2 and 3) usually run hotter anyway beacause of water jacket design. #2 also has adjacent cylinders that fire, and I have seen blown engines with detonation in both cylinders. Airflow distribution also has an affect, as well as fuel distribution. I have also seen motors with blown cylinders that are on the opposite end of the fuel rail feed.
Also the SVT does have hypereutic "cast" pistons... these are not made for FI. They have some advantages over just plain cast pistons, but none of these are to withstand heat. The are stronger and can hold tighter tolerances but they still act as "cast" pistons when it comes to heat and detonation. These are the first to go, we have yet to see an SVT rod fail at any time. It's always been the pistons.
Well, its good to know my thinking was correct on the other thread...
 
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