fuel selection, What kind of gas? brand? octane? Options

[Carlitos Way]

I'm curious. I'm sure a lot of gas selection comes to personal preference, but I'm wondering what some of the engine builders and long-time techs recommend for the Type IV engines that we run. Would your selection depend on the year? (i.e. smog pump vs. no smog pump?) carbs vs. carbs? brand? octane? additives?

I'd love to hear what you guys have to say on the subject.

Thanks,

Carlos

[Dave_Darling]

Depends on the exact engine. If you have a stock engine, follow Porsche's recommendation: Regular (87 US pump octane) for 1.8s and 2.0s; Super (91-93 US pump octane) for early 1.7s; Regular for at least some later 1.7s. (Euro 1.8s were spec'ed for Super; Euro 2.0s for mid-grade.) The "RON" or "ROZ" number listed in the book is about 4-5 points higher than the ratings you'll find on fuel pumps in the US.

If you have a modified motor, particularly if the compression and/or cam grind have been changed, then have a conversation with the engine builder about which type of fuel you should be running.

For the most part, I feel that fuel brands are all but meaningless. I buy from "name" retailers, because I'm not sure how much I trust the "no-name" ones, but I'm not very picky about which "name" I use.

--DD