LRP.....can i use super unleaded, optimax?
LRP.....can i use super unleaded, optimax?
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Discussion

markbigears

Original Poster:

2,485 posts

297 months

Monday 6th October 2003
quotequote all
ive a 1984 fiesta 1.1.....yeah go on, have a laugh.....
this morning with the tank on empty, i go to my trusty shell garage to find their only LRP pump out of service... bugger, oh well theres a BP garage a few miles down the road..... pull in, no LRP.....try a few more garages, all no LRP. On vapour now and manage to get into deptford, where i usually try to drive as fast as poss for the threat of a gang land shootout, to find a dodgy garage that sells the stuff.
Now for the question, can i fill up on another fuel in an emergency? and will the car run ok as long as i fill up with LRP soon after? Dont fancy the heart stopping moments i had this morning. Cheers Guys.

Apache

39,731 posts

312 months

Monday 6th October 2003
quotequote all
yes

markbigears

Original Poster:

2,485 posts

297 months

Monday 6th October 2003
quotequote all
cheers pete, straight to the point...i like your style young man.

peter m

395 posts

282 months

Monday 6th October 2003
quotequote all
One tank of unleaded won't hurt.

My other car is a MkI 1983 XR2 with the Ford Kent 8 valve crossflow engine. These do not have hardened valve seats, so cannot be run on UL all the time. I bit the bullet, and had the head converted to UL with new hardened exhaust valve seats (~£150). Been running for years on UL, but can run on LRP if required. Did not even have to adjust the timing for the lower octane of UL.

Beware that the small print for LRP does state that it may not be suitable for heavy driving or motorway driving ! If you do lots of this kind of driving, it may be worth looking at using additives or a head conversion.

Pete

kevsmev

254 posts

286 months

Monday 6th October 2003
quotequote all
If you have a look in "classics" mag, they usually give a list of places still selling real leaded 4star.

Paul V

4,489 posts

305 months

Monday 6th October 2003
quotequote all
Get yourself to Halfords and get some lead additive, then you can use unleaded and just put the lead in

Valvemaster was recommend, or it you want an octane boost use valvemaster plus.

TT Tim

4,168 posts

275 months

Monday 6th October 2003
quotequote all
You'll be fine running on unleaded, don't bother with Super or Optimax, it's a total waste of money for what you're talking about.

I assume that your car hasn't had any major head surgery or de-coke therefore you will still have what is called 'lead memory' what this is in effect a build up of deposits from years of burning fuel containing lead.

I would quite happily say that you could use as little as 1 tank in 4 of LRP, using unleaded the rest of the time. If, and I do mean if, you suffer any ill effects, i.e. valve seat recession, from lack of lead in the fuel then you need to act. Carrying out a conversion of the valve seats to the hardened variety along with Stainless Steel valves.

I run a Classic car club based in kent and we have plenty of old Triumphs running in the way I have described with no disasters so far!

LRP is due to be phased out over the next few months and so this is not a problem that will go away. If you are really that worried my suggestion would be to carry a bottle of Millers Lead replacement around in the boot with you.

Good luck, I hope that this is of some use.

Tim

streaky

19,311 posts

277 months

Monday 6th October 2003
quotequote all
Remember, different LRPs use different elements to replace the lead previously added to petrol - typically: Manganese (Mn), Phosphorus (P), Potassium (K) and Sodium (Na).

You should always use the same (type of chemistry) LRP and not chop and change between suppliers. Mixing different chemistries could have a deletorious effect on your engine over time.

Note that there is little guarantee that the LRP purchased from 'independent' garanges and some supermarket garages will have the same chemistry from fill-up to fill-up (of their tanks).

Note too, that bottled additives use the above different chemistries as well.

Streaky