Pontiac GTO Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter #1
Hi all,
a lot of confusion here in France regarding this subject:
what kind of gas should I put in my 65 GTO 389CI V8?
currently I use unleaded 98 plus lead additive;
is that correct?
some guys here says they use 95 without additive;
so, where is the truth?
thanks for your feedback;

Eric:frown3::frown3:
 

·
Registered
Joined
·
57 Posts
Discussion Starter #3
hi, gtoguy,
the confusion comes from the fact that all the engines were designed in the 60's according to the leaded fuel used at that time;
the unleaded appears later in the 90's;
so the fact there is no more lead does not harm the valves?
 

·
Registered
Joined
·
193 Posts
You have that backwards. Lead helps the valves to not wear themselves up into the head. Hardened valve seats were introduced when unleaded gas was becoming a reality. In 1973 it was mandated with the 1974 model year.
 

·
Registered
Joined
·
1,611 Posts
The United States uses the R+M divided by 2 method to advertise octane. Don't believe Europe uses that method, just Research Octane number. You really need to study & find out what "95" actually is, I'm betting it is much lower R+M divided by two.
 
1 - 8 of 8 Posts
Top