fuel- what to fill up with?

hifibug57 · Post by **hifibug57** » Wed Jan 25, 2006 8:30 am

here a response which i got from John Lemon :

I must admit to be totally confused about this whole fuel issue. Most people I have spoken to say that with the Beetle motor LRP should be used but with a timing change only if the car pings. I haven't filled up my bug with the new fuel yet.

As far as additives are concerned, I have been told on good authority that the LRP is to be discontinued in about two years time. Only then will it be necessary to add an additive to protect the valve-seats when ULP is used. Some authorities on the subject say you can even use ULP without an additive in a Beetle engine as long as you don't use more than 60% throttle openings for long periods. I am not too happy about that right now and would rather stick to LRP.

It is heat at the valve-seat that causes the problem (lead was used amongst other things to cool down the situation) so the Beetle motor being air-cooled and running hot, plus running at quite wide throttle openings to keep up with modern day traffic, could be a problem. I don't think there are any additives to protect valve-seats on the market yet but Castrol will be introducing one in the not too distant future.

Hope that helps a bit.

ratbugg · Post by **ratbugg** » Wed Jan 25, 2006 9:18 am

I don't know if it still available but there used to an additive that boosted the octane rating to 100. This was twenty odd years ago so I imagine that it was probably lead based.

Post by **fig** » Wed Jan 25, 2006 5:38 pm

Yeah, this whole phasing out of leaded fuel is not good news for us aircoolers.

I've heard so much conflicting advice that I've just decided to ignore it all and keep filling with LRP. I haven't changed the timing and haven't noticed a problem with LRP and pinging, but I'm going to be keeping an eagle eye on the valve gaps to see if there's any evidence of the seats receding.

The other thing is that LRP will only be sold where there is sufficient demand, so it may be a good idea to start filling up at the same garage always in the hope that they keep stocking it.

beetlepower · Post by **beetlepower** » Fri Jan 27, 2006 12:08 pm

m filling up with lrp but i am adding injections of lrp and octane booster, that i got from engen garage just in case

XV Pilot · Post by **XV Pilot** » Fri Jan 27, 2006 12:27 pm

My engine will be due for a rebuild in about 2 years, so I'll probably take that opportunity to put in hardened valve seats and run it on unleaded. In the mean time, Bev Bug seems happy enough on LRP now that I have retarded her timing a smidgin.

- XV

RotorBug · Post by **RotorBug** » Fri Jan 27, 2006 3:59 pm

Buy proper 102 octane race fuel.Its leaded and imported.
Only R6.75 per liter , but you'll gain some more horses.With the high octane you could run a bit higher C/R and more timing.
Yust a thought........

flatfourfan · Post by **flatfourfan** » Mon Jan 30, 2006 2:30 pm

Even leaded 102 is being phased out..........