Valve Deposits

[WardL]

I'm wondering if anyone has noticed much intake or exhaust valve deposits when they have torn down their engine. In the last 25 years the EPA/OEM/Oil companies have required more additives to reduce deposits and keep injectors clean. I'm sure many of you buy the most expensive premium gas you can find to burn in your Cobra. Have any of you taken apart your engine and found your heads/valves with many deposits?

I've just recently realized the Top Tier additive packages are primarily intended to keep the injectors clean, but they also keep the intake valves clean. Back in 1965 there were no gasoline additives to keep injectors or intake valves clean! That almost makes you wonder if we really need the additives today in our 1965 vintage V8s!

Again, anyone seen any deposits when getting a valve job?

[Rick Parker]

I used to work at a BMC Dealership back when British sports cars were real popular. We used to advise everyone to avoid Shell gasoline, because at the time it's usage would create large fluffy tan colored deposits on the exhaust valves. Left long enough it would impede air flow.
The current fuel injection systems and the current engine operating tempratures keep the A/F ratios lean enough to minimize build up.