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MG MGA - Leaded petrol

Is anyone still using leaded petrol?

There aren't many places to get it but more "interesting" is the price. I use a place near Lancaster and it's 1.51 per litre. US residents might like to know that means 140 USD to fill the tank!

I haven't fitted hardened valve seats (yet) so rather than mess with additives or other dubious fixes I normally use premium petrol and fill up with leaded 4 star from time to time.

Recently I have got the car set up really well and it's running better than ever. (100+ mph easily and 29 mpg). I've filled up with a couple of consecutive tanks of leaded now and really would like to keep using it.

Does anyone have any ideas?

Neil
Neil McGurk

Hi Neil - that sounds an extortionate price compared to already steep 97p for unleaded - I use valve master plus additive which adds about 5p / litre to the price - seems to run OK but I do know that B series engines don't like unleaded - have you tried Optimax or super unleaded? Cheers Cam
Cam Cunningham

Thanks Cam,

Following what I seem to remember from this BBS I have been nervous about using additives. With the fuel cost difference I was more tempted to do the head, but it is already gas flowed with larger valves (done in the late eighties - and clearly very well).

I always use Super or whatever they call the higher octane fuel, when not using leaded. (Are there particular brands/products that are better than the rest?)

If you can recommend it, perhaps your solution is a better route. Which additive to you use (I assume an octane booster?)

Neil
Neil McGurk

Neil

Why not get the head converted and be done with it, then continue with the Super (Optimax)fuel? Surely, this will not have any effect on the gas flow work that has been done, or am I wrong?

I use Optimax with my unleaded head. The difference in performance to standard unleaded is very noticeable and, no pinking!

Steve
Steve Gyles

Steve,

Perhaps you're right, but I just don't want to pull the head and spend a couple of hundred quid when it is running so well.

I only do a few thousand miles per year so I suspect I can get another few years from unleaded (even without the occasional 4 star).

What I am wondering is whether I would get benefit from using an additive and if so, which one.

Neil
Neil McGurk


Neil

I have just looked in the archives because I remember it being discussed late last year. The following link has some interesting comments from Barney:

http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgbbs&access=&mode=archiveth&subject=6&subjectar=6&thread=2006101620385128803

Steve
Steve Gyles

You could get some 100LL avgas and mix it in with your usual gasoline.
Del Rawlins

Thanks Steve, I remember that one. I'm sure there was also an earlier thread about additives, I'll try and find it.

Neil
Neil McGurk

Hi Neil, I have used Castrol Valvemaster plus since I bought the car 4 years ago -(MGOC do a deal 6 bottles for the price of 5) about 10,000 kilometres -this was on the recommendation of the PO who always used it - I don't know what the car would run like without it as I haven't tried it - the head has not been modified and I have heard all the arguments about lead memory etc - but the engine runs well with no pinking - when it needs it I will lift the head and do a conversion and then probably use Optimax or similar -which is what I did with my GT previously- cheers Cam
Cam Cunningham

Thanks Cam,

I think I will give it a try.

Neil
Neil McGurk

Seeing as how you may be removing the head sometime, why even worry about lead in your gas? We here in the US used to worry about the lack of lead, but it has proven to be for nothing. Keep on checking valve clearances for valve seat recession, but it probably won't happen.
Tom

Hi Tom, I use the Valvemaster plus because it has an octane booster - taking the standard unleaded from its 95 RON closer to the 98(?)of the 4* leaded fuel used during the 1960s in the UK. The super unleaded over here is 97 RON I think, but I use the additive instead as not all stations have the super - cost is about the same. What is the octane rating of unleaded in USA? cheers Cam
Cam Cunningham

Cam

You may find that Shell Optrimax is 98+. Certainly goes well with my motor.

Steve
Steve Gyles

Steve,

I'm passing by Preston this afternoon, can you recommend a Shell station with Optimax. I know it sounds like a stupid question as there are probably loads, but just to avoid driving around too much.

Thanks,

Neil
Neil McGurk

Neil

I do all my refuelling 10 miles west of Preston, junction 3 on the M55. Take the Fleetwood road from the exit. Shell is half a mile on the right.

That all said, I would have thought that almost every shell station will have at least one pump selling the stuff.

Steve
Steve Gyles

Just done a search, not as many stations as I thought! It seems that Optimax is now overshadowed by V-Power! 99 RON octane rating. I need to do some more research.

Neil
Neil McGurk

Neil

I suspect that V-Power has actually superceded Optimax. My last tankload was V-Power, but it was £1.06 a litre! Car goes well on it though.

Steve
Steve Gyles

Neil

Try this search engine for Shell stations: http://www.viamichelin.com/b2b2c/gbr/dyn/controller/dlhomepageWAI?productId=61429

My search for Optimax on the Shell site took me to V-Power, hence my suspicions that V-Power is now all you will find.

Steve
Steve Gyles

Hi Steve,

I found a site with all the stations shown on different scale maps and planned to go to Forton M6.

Unfortunately got my mileage calculation wrong and ran out on the way! So got 5 litres of std unleaded and a tank of super unleaded 97 octane instead. Funnily enough the car still runs great?

Now it's time to fix the sender unit!

I came to the same conclusion regarding V-Power and Optimax. (1.06 is much better than 1.51!)

Neil
Neil McGurk

Neil

You should read this post by Steve Simmons that I recalled from a few years ago.

http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgbbs&access=&mode=archiveth&subject=6&subjectar=6&thread=2004021516310832171

Steve
Steve Gyles

This thread was discussed between 14/06/2007 and 20/06/2007

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.