Now guys, im not to sure, cause i have only just got into vw's, this might sound dumb to some of you smart ones out there, but i have heard u dont have to put the lead adative into the fuel cause vw's have alummium heads.
Is this true??
[ Edited on 15-3-2006 by Dougie ]
barls ·
this has been discussed before on here and so i dont step on anyones toes im going to say it comes down to personal choice as some do some dont, im an additive person as its cheap insurance as the one i use will cover the work if it happens while using their product
Yep, cheers mate for the link, i think i understood it.
Schmoburger ·
Ihad the feeling that fuel additive use was not to do with the composition of the head, I thought it was specifically concerned with preserving the valves themselves... also clear as mud on my part, but anywho, I use the crap anyway, just in case...cos the less times I have to fix heads/valves and hence remove the engine, the better! 👍
I have heard of some additives causing issues like poor performance, gummy carby's, fouled plugs etc... but i havent had any of these symptoms myself. I think the additive I use is a Penrite product. 🙂
Dougie ·
Yeh, ok
oval TOFU ·
Flashlube for me... I got 5L of the stuff, so i'll be using it for a while (and have been for the past 5 years too)
ian.mezz ·
Since this question has raised more questions than answers, here is my
> attempt at reasoning through this. Basically, I would recommend you
> buy gasoline of the appropriate octane rating for your compression
> ratio, timing, engine condition, and operating conditions and drive
> assured that you have done your best.
>
> The argument that fuel has changed and that you can make up the
> difference between 1960's or '70's gas with the re-addition of lead or
> lead substitutes over-simplifies the issue. Gasoline today is nothing
> like that product refined and supplied when the VW air-cooled engines
> were built. Many additives and detergent packages have come and gone
> along with the lead. The most common of these is now ethanol, an
> alcohol. MTBE, an ether, was a staple oxygenate before it was found
> contaminating groundwater. These unfortunately make reformulated
> gasoline more expensive to produce, reduce the energy density thereby
> decreasing mileage, but do offer benefits of lesser pollution in some
> engines in certain climatic and altitude conditions from certain
> byproducts of combustion over un-reformulated gasolines.
>
> Bear in mind that VW has been using the proper engineering and
> materials to keep their cars running on unleaded fuel for a long time.
> The valve seats are special hardened materials already in place to keep
> up with cylinder head temperatures often exceeding those in
> water-cooled engines. The VW engine has bronze-alloy valve guides
> which do not require any lead based lubrication, and the design of the
> valves does not need valves seals, so they are lubricated very well
> from the splashed oil on the spring end of the valves. The VW engine
> does not require leaded fuels for valve stem lubrication purposes.
> Furthermore, silicon-bronze valve guide inserts found in VW air-cooled
> heads on all Supers are still considered proper replacements for
> "lesser" engines undergoing upgrade for unleaded fuel use. Later VW's
> utilized chrome plated valve stems which further increase valve stem
> durability and this further increases compatibility with lead free
> fuel. So don’t worry if you can’t get leaded gasoline. In fact, the
> 75-79 California cars had catalytic converters, which Require the use
> of unleaded gasoline! If you were throw your wallet at this issue and
> were also willing to risk Federal legal trouble by using LL100 aviation
> gasoline on public roads, you would likely exceed your cost in valve
> repairs with lead-fouled plugs alone...and wait until you struggle
> getting a lead-encrusted plug out of a soft aluminum head, just ask the
> flying-VW crowd! Lastly, commonly available potassium-based valve
> lubrication substitutes offer a feeble shadow of the protection lead
> provided in the engines that benefitted from it.
>
> The top end of an air-cooled VW should warrant some attention as miles
> accumulate due to often high operating temperatures. Rather than
> obsessing over the last mile of utility until failure, save your
> considerable additive money and plan on compression checks, resurfacing
> valves or replacing them with those of the chrome stem variety and
> otherwise refreshing heads at more frequent, 50K to 100K mile,
> intervals.
>
> Best Regards,
> Alan