Unleaded

[yroll]

Was all engines for Excel designed to be run on unleaded fuel?
I've searched the forum and got different answers, do you all run it on unleaded?

[amarshall]

Was all engines for Excel designed to be run on unleaded fuel?

Yes - all Lotus 9xx series engine are designed for unleaded, but some need a higher octane rating than regular (i.e. they need 97 or higher).

I've searched the forum and got different answers, do you all run it on unleaded?

[rbgosling]

I try to stick to Shell V-Power (Nitro+ as they now unnecessarily add to the name), but if that isn't convenient I seek out a 99-Octane fuel. Tesco is 99, but several "super" fuels (BP, Sainsburys, Esso as well I think) are only 97. This is for an HC engine - the lower-compression engine probably doesn't mind quite so much.

[amarshall]

I try to stick to Shell V-Power (Nitro+ as they now unnecessarily add to the name), but if that isn't convenient I seek out a 99-Octane fuel. Tesco is 99, but several "super" fuels (BP, Sainsburys, Esso as well I think) are only 97. This is for an HC engine - the lower-compression engine probably doesn't mind quite so much.

I'm a bit wary of Tesco 99 because of the ethanol content. We still don't have a definitive answer about the compatibility of a couple of the hoses.

[KevW]

Unleaded? I wouldn't know where to buy it these days.

I use the higher octane petrol when I can.

[amarshall]

Unleaded? I wouldn't know where to buy it these days.

I use the higher octane petrol when I can.

Just quoting that so you can think about you wrote

[yroll]

Unleaded? I wouldn't know where to buy it these days.

I use the higher octane petrol when I can.

Just quoting that so you can think about you wrote

Why can't we "like" posts?

[chrisw2811]

Mine's 1985 SE so I don't have a voting option . 95 RON unleaded seems to work fine, with 97 RON when I feel like it.

[Hawaiis0]

Mine's 1985 SE so I don't have a voting option

That makes your choice one of the first 2 options, up to 1986; - 1986

[alanmoss]

I use 95 ron most of the time and just occasionally have a fill up with Shell V Poweror BP Ultimate top spec because they have better aditives for cleaning etc.

[KevW]

ok, ok, leaded !

Goddamn wiseguys! (I've just been watching Joe Pesci in Goodfellas)

[alanbell]

if you want to use 95ron in an se retard the ignition or take it easy on the loud pedal. premium grades of at least 97ron should be used to avoid pinking which has a serious effect on the life of an engine. the difference between an engine that can run on unleaded and one that cannot is that in the former the valve seats have been hardened to compensate for the loss of the lubricating effect of the lead. as angus said from day one in the Jensen healy all 900 series engines had hardened valve seats and so could run on unleaded.

[fueltheburn]

Who buys a lotus to take it easy on the loud pedal?

[yroll]

if you want to use 95ron in an se retard the ignition or take it easy on the loud pedal. premium grades of at least 97ron should be used to avoid pinking which has a serious effect on the life of an engine. the difference between an engine that can run on unleaded and one that cannot is that in the former the valve seats have been hardened to compensate for the loss of the lubricating effect of the lead. as angus said from day one in the Jensen healy all 900 series engines had hardened valve seats and so could run on unleaded.

I've also heard from somewhere that if the valve guides are the same metal as the valves you need lead additives, this might be just some nonsense tho

[chrisw2811]

Mine's 1985 SE so I don't have a voting option

That makes your choice one of the first 2 options, up to 1986; - 1986

Ah ha. Should have read it with my specs on instead of contact lenses.
Thanks.