I know this been talked about already, I have read those posts.

I have a 1.5 litre air cooled engine. Some people have said using shell optimax or premium unleaded you wont need that additive stuff... is that true or will you need the additive regardless of the type of unleaded fuel. I talked to the mechanic at this VW workshop for older VW's he said you can use it but eventually the engine/valves will get damaged,wont be right away but its a gradual process.... any further ideas would be good.

Thanks
Nick

I've been told because of the steel inserts in the valve seats on VW's you can run normal unleaded without an additive and it's fine. I've ben running both premium and normal in my kombi and it runs fine on either. My engine is a 2 litre but I think the earlier VW engines have steel inserts too. There tends to be a lot of different views but going from my experience it's been fine. Although an additive might be a nice extra measure...
Cheers,
Dustin

[Edited on 11-5-2005 by dusto81]

No additive necessary, even on normal octane fuel, but it doesn't hurt to add it if you're worried. Also only use premium if you need the higher octane (to stop pinging), or if your car is noticeably more economical on it, otherwise it's a waste of money.

So which VW engines have the hardened valve seats from the factory?
Is it only the valve seats that will benefit from the additive? I generally use the flashlube brand additive which describes itself as an "upper cylinder lubricant. When I use the Shell LRP I don't bother with the additive. I'm also keen to hear what ppl have to say on this topic...
Cheers!
Toby

What you said about heads wearing out eventually is spot on. unless you have hardened valve seats in which case dont bother with the additive

I use 98 octane fuel with additive. My uncle used to be an engineer for a famous aussie aircraft company. They did testing on the additive and how it affected their engines. The result was that the heads ran cooler.

Also from my own university engineering studies i know that using a higher octane fuel means increased efficiency in extracting energy. For the same volume of fuel you will get higher energy out, or to put it another way, the same power out for less volume of fuel

If you were going to be racing your engine, or running the tits off it everyday to work, then you will notice the power increase. But for the rest of us daily drivers you'll notice smoother running, possible quieter engine noise, lower engine temps and most importantly, better fuel economy

Dont believe me? Just do 1 full tank of 98 octane (with additive if you dont have hardened valve seats) and see. It'll cost ya probably about $5 extra but its worth it

Lastly as for Shell Optimax, my mechanic Andrew Dodd, reckons hes extensively used it but found it leaves a residue on spark plugs and generally doesnt burn that well. Dunno how true this is but ill take his word for it. Been using Mobile 8000 or BP Ultimate

I use ultimate 98 and upper cylinder lubricant. I bought a 1 litre bottle of the upper cyl lubricant for about 14 bucks and this will last me for months, which is much cheaper than getting my heads re-done.

I've been using Caltex 98 ron for the past 3 years. My test for increased power is the Mooney Mooney hill, for which I am 10-15 kmph faster going up. No additives needed. and no rebuild.....touch wood.

vw cyl heads are designed to use unleaded fuel as the us market was vw biggest. unleaded fuel eg california is all you could use ...think there are still a lot of aircooleds running over there? vw valve seats are pretty tough! over heating due to poor fuel quality is the major killer......be careful on reco heads as they usually bump up the CR ...higher compression=higher headvtemps on regular fuel = increased oil consumption=more deposits in cyl head chambers and sparkplugs=a short lived aircooled experience?.......most valve failure other than burnt valves are loose valve seats..overheated heads that crack thru the exhaust port to the exhaust seat which in turn beome loose...try and keep it cool..run quality fuel sensible compression and a correctly tuned engine will give good service..cheers DSK steve

still no 100% sure answer though lol
I guess its just up to the individual to decide what they want to do based upon the info given here.

Standard motor - standard unleaded.

Compression ratio higher than 8:1 use Premium.

Hardened valve seats dont need additives.

Use additives if it makes you feel better

And i quote: First,"ALL"factory VW air cooled heads from 1967 and later with the hard chromed stem valves can run unleaded fuelsw just the way they come from the factory."ALL"VW heads have steel intake seats,hardened steel alloy exhaust seats,brass guides and tri-metal exhaust valves,which have hard chromed stems.GB may he rest in peace.:thumb

Just read the little plate near your fuel tank, or the owners manual.

It clearly states that the minimum requirement is 91 RON (standard uleaded). You can go as far above this number as you want, but just dont go below it (which is hard to do, as Australian standard is 91 RON for unleaded fuel.)

Regular unleaded is absolutely fine.

^^^^ unless your CR is higher, i.e. your heads aren't stock, as Barry (Bizarre) said. I read somewhere that Germany had only unleaded fuel from the 60s. Can anyone confirm this?? I can't remember where I read it... maybe on this forum?

I know Californication has not had leaded for about that time

Sorry guys but since I butted in on the post I'm gonna run with it. I still don't feel 100% confident that I can run unleaded in my stock kombi based on a quote from God (GB).
The PO always ran flashlube additive with unleaded. Also, what does this stuff do to the RON of the fuel used, if anything? I know that my 68 notch has hardened seats, but that's beacuse I had them fitted when the heads were semihemi'd and had the 3 angle cut done. Don't want to be a pessimist on this, just want to be sure!
Cheers!
Toby

hey.... that is fine ....... it just means there is a whole lot of bugs in Cali... USA..... Europe........ not to mention mine that HAVENT been using additives.

:thumb

not bagging at all here....... just confirming (sorry stating) that they are a feel good product for bugs.

Since 1967 ALL VW heads had hardened seats

If you want more back up read here

http://www.shoptalkforums.com/search.php?mode=results 

Look in particular from a person called Marc.... fairly knowledgable(sp?? i'm tired)

I would save the pennies for something else... better oil and plugs??

i asked vintage veedubb supplies they said definately yes "valvemaster "
plus unleaded , i use that with optimax in a 1600 unknown of whatengine setup and she runs awesome with optimax

i use flash lube in both of my bugs no problems oh and premium unleaded ether the 98 if im on the highway or just the 95-6 around town. cause i found my bug pings and carries on on unleaded.

what compression and advance are you at Barls??

stock compression but not sure what advance as my old man set it initially and i havent changed it. it will run on unleaded but not as well as it did on the old super.

I notice some pinging in certain situations (eg - uphill, before I change down - don't lug it!) even on Premium. I use BP Ultimate whenever possible, but have never used valve lube. I think I will after the impending engine rebuild, but eh, probably not necessary is it?

Cheers!
Aurel.

are you certain what your timing is???