Re: PRV Octane

["content22207" <brobertson@xxxx>]

The reason I burn 93 octane is because my engine's compression is
9.5:1, timed 10-11 degrees BTDC (European spec). Have had
pre-detonation problems with 89 octane, especially in the summer.
Would suspect anyone running one of Houston's engines is in the same
situation.

High octane fuel is actually COUNTER PRODUCTIVE in a low compression
engine. Doesn't burn as well, which leads to carbon buildup.

Of course once an engine is carbonized, you may have no choice but to
burn high octane fuel. Not only will the deposits reduce cylinder
volume slightly, raising compression (in a bad way), but they glow red
hot and can cause low octane fuel to pre-detonate.

Bill Robertson
#5939

>--- In dmcnews@xxxxxxxxxxxxxxx, "cruznmd" <racuti1@xxxx> wrote:
> 
> 2. Which gas: I asked this question some months ago. I was told by a 
> list member that the "91" rating is some odd-ball kind of research 
> number or European octane rating that actually corresponds to 87 
> octane at a U.S. pump. If you look at the pumps next time you go, 
> you'll see 87, 89, & 93. There -is- no 91. Most owners I know (except 
> Bill Robertson) run 87 octane. Bill's engine is a replacement from a 
> Renault R30. It has minor differences that require the higher octane.