If you know the research about octane and flamewalls and compression ratios, you would have a different attitude about that. Low octane fuel will demolish a high comp engine. I have taken apart Porsche engines they were putting in Beetle vans, with the rings all cracked and melted into their landings from using low octane for their compression ratio. And this despite the decal by the gas tank stating a minimum of 92 octane!!! This engine was still running, but I have seen engines with holes in the heads, the pistons, one which was ruined beyond repair with the hole outside of the valve insert. It is not good if you use low octane in a high comp engine. The flame wall is meeting the piston as it comes up, and when the heated wall of fire hits the piston and you hear the knock, back off, or you will ruin your engine. The engines today have knock sensors sending data to the computer to retard the timing when the flamewall gets too close to the piston crown. When timing was only a mechanically actuated centrifugal advance, one couldn't actually retard it, so the only thing one could do is back off the gas, or go around with permanently retarded timing, which defeats the purpose of higher compression: greater engine efficiency and/or more power. An old wrench gave me an engine for taking it out of this van he bought cheap and that's what I found when I took it apart. Happy to say, though, bottom end was excellent. Nice thing about those engines - is it was not too expensive to replace those pistons and cylinders. I had me a new engine for the labor and $80.00 for new set of P&C and a valve job with new exhaust valves. Gasket set was the second most expensive item: $29.00; for regular Beetle engines the gasket set was only $4.00, and a new set of P&C was less than $40.00 for Brazilian Cima/Mahles or a Jap brand name escapes me), both of which were close to German quality. The only safe thing to do when rebuilding the Porsche engines is to lower the C/R, because people think, it's just a VW (van/microbus). It doesn't really need premium gas. Until, of course, it's usually too late...
Stanley ________________________________ From: Creative Residential Designs <[email protected]> To: [email protected] Sent: Tuesday, March 17, 2009 7:37:45 AM Subject: [Nighthawk Lovers] Re: Gasoline, octane and oil Try telling that to my '69 GTO, Dick. It will NOT run on anything else...period. It doesn't care what you or I think about premium gas, it will ping and knock and carry on until I feed it the best gas there is. (Texaco or Shell premium ONLY). I just read a study on gas on the 'net as well. Interesting how abrasive low-end fuels are to an engine. I'll try and locate it again. Apparently it's one of those "you are what you eat" situations. HotrodMamma. ----- Original Message ----- From: Dick MacInnes To: [email protected] Sent: Monday, March 16, 2009 9:10 PM Subject: [Nighthawk Lovers] Re: Gasoline, octane and oil The only place to get the proper service Manuel is Helm. Inc And premium gasoline is a waste of money, I don't care what anyone has told you. Dick --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
