High compression 4.6

[redandy3575]

Just out of curiosity, can a high comp 4.6 V8 run on standard 91 octane unleaded comfortably without causing damage?

[Battler]

If it's standard it should be fine.

[davidsonsm]

Just read this. The engine that was built aimed for 10.2:1. I'd be sticking to a min of 95RON.

http://www.carbibles.com/fuel_engine_bible_pg3.html

[Battler]

[QUOTE=davidsonsm;2532927]Just read this. The engine that was built aimed for 10.2:1. I'd be sticking to a min of 95RON.

I thought the 4.6 HC was 9.35:1:o

[mtb_gary]

Just read this. The engine that was built aimed for 10.2:1. I'd be sticking to a min of 95RON.

Car Bibles : The Fuel and Engine (http://www.carbibles.com/fuel_engine_bible_pg3.html)

Thanks for for the link Sean, a long but detailed article that was not just techno babble.

[davidsonsm]

[QUOTE=davidsonsm;2532927]Just read this. The engine that was built aimed for 10.2:1. I'd be sticking to a min of 95RON.

I thought the 4.6 HC was 9.35:1:o
I was referring to the engine in red andy's new p38, which he bought off me. I'd had a new engine built for it when it was under my ownership.

[Pedro_The_Swift]

How did you actually aim it at 10.2?

[davidsonsm]

How did you actually aim it at 10.2?
By skimming the HC pistons along with decking. Done by orger engines.

[TheTree]

I noticed the owners manual said 95 RON for the HC engines

[banarcus]

The occasional use of 91 wont hurt it. Knock sensors take some of the timing out of it so all you lose is power.

[Pedro_The_Swift]

By skimming the HC pistons along with decking. Done by orger engines.

I wonder if there are advantages one way or the other?

[redandy3575]

Tried it on 98 octane, seemed to not like it as much as the 95. I'll be keeping a couple of bottles of octane booster in the boot just in case.