Drag event...

Wed 15 Aug 18 07:35

Re: Drag event...

Front ones should be a wave. Rear ones should be close to a flat line.

I've checked for vacuum leaks and made sure the intake and exhaust manifolds are tight. These are custom made stainless headers for a perfect fit and no clearance problems.

Going to be another week or so before the new plug leads arrive. If those are not a fix for the issue I will have to dig deeper.

Wed 15 Aug 18 18:47

Re: Drag event...

It is a big coincedence that the only ones not showing misfires are new ones
When did it have plugs last and what type
I like NGK TR6s as I don't trust plugs to last as long as the platinum ones claim and you can buy a set for the price of 2

Thu 16 Aug 18 08:14

Re: Drag event...

Pinhead wrote (View Post):It is a big coincedence that the only ones not showing misfires are new ones
When did it have plugs last and what type
I like NGK TR6s as I don't trust plugs to last as long as the platinum ones claim and you can buy a set for the price of 2

I have NGK TR6s too. The fine point Iridium type. Used those in my old Challenger for years too.

Fitted these in the Corvette a few years ago. Less than 10,000 miles on them for sure. I pulled the few that are easy to get out (changing plugs on a C5 is a nightmare) and they all look fine if a little on the lean side to me.

In my 40 years experience of fault finding in systems I find it is always best to look at the last thing messed with before the fault occurred. Which is the plug leads. Rule that out first. Then see if you killed that Gremlin or if he is hiding behind something else.

Thu 16 Aug 18 08:20

Re: Drag event...

Oh I am putting in low impendence plug leads to raise the current level in the spark. The plugs will wear out faster but I usually fit new plugs every 5 years anyway. The stock plugs are supposed to last "100,000 miles". Changing them at 35,000 for the NGKs made a noticeable difference I wasn't expecting.

Thu 23 Aug 18 08:01

Re: Drag event...

Finally received the new ignition leads for my Corvette last night.

The car is now firing on all cylinders.

It must have been this way since I had the headers installed at the beginning of the year. I thought the sound and feel was down to the loud stainless exhaust pipes. But it feels and sounds so much smoother now and I can confirm the catalytic converters, which were throwing up error codes, are actually fine. Secondary o2 sensor voltage is now level and stable. Showing that the Cat's are working fine.

I still can't believe it ran a 12.95 like that.

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Thu 23 Aug 18 18:12

Re: Drag event...

Great result
Certainly got more in it