Hey all, the 62 turbo tuning continues and is somewhat streetable at this point.

Here is my quandary; the front 3 plugs are light brown and are running a bit too lean and the rear 3 plugs are black and covered with soot and way too rich?

The fuel is delivered by 4 injectors in a throttle body and all 4 butterflies are synchronous. I checked the injectors and they appear to be injecting uniformly and the butterflies were nearly synchronized so I made a small adjustment.

Long Hurricane intake. Recent valve lash adjustment.

Dual Dutra Duals, the rear dumps into 2'' pipe and into a 90 degree bend the pipe steps up to 2 1/2'' just before the front exhaust merges, the front dumps straight into the log that parellels the engine. About 2'' in front of the merge the log empties into the turbo.

My first guess is that there is some weird resonance or harmonic in the exhaust is the cause of this imbalance. But the exhaust guys that I consulted disagree. They say the rear pipe is less restricted and is more free flowing. But that is where my plugs are fouled.

We've batted around a lot of ideas including the possibility that a rag got sucked into the intake and blocked 4, 5 and 6. I doubt it though as my boost gauge is off #6 and is very responsive.

Help me solve this mystery and I'll nominate you for the Nobel Slant Prize!

Cheers,
Lobster

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These ones go to eleven...

Swap the 2 rear injectors with the 2 front injectors and see what happens.

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Wise and will do. Thanks!

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These ones go to eleven...