Is it really bad (I think it is!) to use unleaded gas in a 260 alu head? How many miles before the valves sink into the ports?

It's not for me, as I am ZXed, but for a fellow member...

Every comments are welcome, fred

you actually dont have a choice thats why you have to put in hardend valve seats in

It would take a lot of use and a lot of miles with unleaded gas before any problems would show up if the valve seats are in good shape to start with. If they are already suspect, having the hardened steel seats installed would solve the problem entirely.

I used unleaded in my Z for years with no problems with the stock seats. Not that it might have had problems right after I got rid of it though.....:cross-eye

Thank you, so we have a brave here, If I read you correctly, I did use unleaded for a long period of time without any bad side effects? was it a 240-260 ? I will tell him that (it's not my car after all!!!!)

Thanks, fast repply as usal... Fred

Used it in 240's and 280's.

I had one car that had over 100K on it and I know it never had any leaded gas put in it for more than the first couple years of its life. And I know he was not into doing preventive maintenance.

Using unleaded is not going to cause significant damage to the seats in a short time. It's is over a long period of time that the damage is done. Lots of other things also will may have an impact on how long it lasts, such as valve adjustments, fuel mixtures, spark plug heat range, timing. Any things that will affect what is going on inside the combustion chamber will have an effect on how quickly the unleaded fuel will cause the seats to deteriorate. So there are variables in how long the seats will/can last.

I have a 260 2+2 with standard head and seats, and I run it on PULP...never a prob, just don't using standard unleaded...its shite!:classic:

Fred,

here in Germany we can only get unleaded fuel . I drive my 240Z and our 280 ZX for years now unleaded without problems, I only changed the ignition timing a little bit a n d I always use an additive whenever I fill unleaded gas at the station. No problems !!!

Rolf