Engine no. LF80ESS

[sujitroy]

I have this engine. I'm aware from the ESS in the part no. it's a factory replacement block. The engine came out of a UK K reg RHD car imported into the US.
What does the LF80 mean?

Sujit

[flying farmer]

It was the 80th factory replacement short engine built.

My K reg Stag came with LF8ESS. It should have the dished 8.8CR pistons fitted from the factory, though mine had been rebuilt with the MK2 domed pistons by the time I bought the car.

Neil

[sujitroy]

Hello Niel,
When you say dished pistons, are you referring to the example in the photo. This is the piston in LF80ESS. Do some people call them flat pistons? I had a Fed Mk1 and the pistons in that looks domed providing a lower compression. Did the Mk2 have the same domed pistons hence a lower compression than a UK Mk1?

Sujit

[trunt]

Jumping in..

Yes that looks like an early Mk1 (8.8 CR) slightly dished piston, but Federal never had domed pistons, just deeper dished versions to reduce the CR. Domed pistons as fitted to ROW Mk2 gave a HIGHER compression.

[mole42]

Hello Niel,
When you say dished pistons, are you referring to the example in the photo. This is the piston in LF80ESS. Do some people call them flat pistons? I had a Fed Mk1 and the pistons in that looks domed providing a lower compression. Did the Mk2 have the same domed pistons hence a lower compression than a UK Mk1?

Sujit

My UK-built recon Mk2 (1985ish) has those pistons. I understood that they were the commonest aftermarket pistons available at the time.

[trunt]

My UK-built recon Mk2 (1985ish) has those pistons. I understood that they were the commonest aftermarket pistons available at the time.

Still the same I think, the County Pistons available now from all usual suspects are the same, i.e 8.8 CR (maybe a bit less on a Mk2 due to the very slightly larger head cc?? ) they are dished byaround 3.5cc.

From what I have seen on the Forum the domed type can be a bugger to find.

[sujitroy]

Hello Niel,
When you say dished pistons, are you referring to the example in the photo. This is the piston in LF80ESS. Do some people call them flat pistons? I had a Fed Mk1 and the pistons in that looks domed providing a lower compression. Did the Mk2 have the same domed pistons hence a lower compression than a UK Mk1?

Sujit

I got my domed and dished wrong. My Mk1 fed have deeper dished pistons, hence a lower compression.

Sujit

[trunt]

Sujit

As far as I know the early Federal Mk1 had those slightly dished pistons, same as UK .. the deeper ones came later.

looking at the ROM I see that early Mk1 was 8.8 so same as UK MK1
1972 was 8.0 (so probably the deeper dishes came in there)
1973 was 7.75 (drop probably caused by the slightly larger Mk2 heads?)

[garyf]

Why the lower compression for the US?
to meet emissions perhaps?

[flying farmer]

I think the regular petrol in the USA is a lower octane rating than in the UK, something like 87 for regular, and even their premium fuels are barely up to our regular unleaded rating.

Neil

[trunt]

I think the regular petrol in the USA is a lower octane rating than in the UK, something like 87 for regular, and even their premium fuels are barely up to our regular unleaded rating.

Neil

Actually that’s not the case, yes regular is 87 and super is 93 but the method of measurement is different. Over there it’s RON over here it’s RON +MON /2. MON is a much lower number. So say 97 RON + 89 MON/2 gives 93.

And yes it was emissions.. they started in 1968 with simple things like retard the engine on idle, (which runs hotter burning emissions plus causes increased airflow flushing in burned fuel) then tamer cams, lower compression, air injection to the exhaust manifolds and eventually catalytic converters.

I had had quite a learning curve when I got here!


Its going to to be interesting when I get the stag running, I’m running 9.0 CR with no retard module and will need to get it through the emissions test. The electronic ignition should help, also planning a wideband O2 sensor to nail the carb adjustment but I’ll probably need to retard it a bit on the day (and watch the temps carefully!). Then wait for a cold day...

terry

[garyf]

USA is a place I would love to go to one day,Is it true they like us Brits over there?
Now Trump is in charge it's even more appealing to me
That reminds me,I must get myself a MAGA hat off the net

[72BLUE]

That reminds me,I must get myself a MAGA hat off the net

Is it one of these.........?????

hat.jpg

[ukbiggles]

Love the hat!!

[trunt]

Nice hat..

I always tell them that july4th is called thanksgiving day in the UK.

When we give thanks that we got rid of those pesky Americans..