Pistons and Liners?

[G_Reaper]

Does anyone know wether Lotus only fitted the 'Nickosil' piston and liners in the HC Esprit engines or were they also used in the last of the non HC esprits also at around 1986/87 just prior to the HC introduction. As these cars have all the other mods including the bendix brakes etc. but no HC engine.

[jonwat]

I was under the impression that only the HC & later engines had the aluminimum liners with Nikosil coating which cannot be fitted to earlier engines as the machining is different.

Hope this helps

John W
'95 S4s

[cnh1990]

Iknow that the HC and later cars were fitted with Nikosil liners and chrome coated pistons. Jim looked into it while rebuilding his engine last year. I believe the pistons and liners can be fitted to an earlier engine. He went with just the forged pistions to correct the chronic piston crowning in the 85 and earlier turbo cars.
Calvin

[lotusguy]

GR,

If you don't have an HC engine, you do not have the nikosil liners and pistons. This is designated by the second character in your engine number-If you have AC and an HC engine, this character should be a 'P', if you have AC and a standard 910 engine, the character will be a 'D'. It is the forged piston which defines the engine as HC (High Compression) as the piston crown is reshaped increasing the compression ratio of the 910 engine from 7.5:1 to 8.0:1. You can retrofit these to a standard 910 engine, but, plan on $1,200USD per hole-$4,800USD - very cost prohibitive. I rebuilt my engine and installed forged JE pistons which I had coated with my cast iron liners and raised the comprssion ratio to 8.5:1.

The appearance of the coated pistons (I'm not certain they were chromed) came with the SE engine in mid-'89. Happy Motoring! Jim'85TE

>> Edited by lotusguy on Friday 21st February 15:55

>> Edited by lotusguy on Friday 21st February 15:59

[cnh1990]

Also SE pistons/liners I believe have a lower compression due to higher turbo boost. So there are differences in models.
Calvin 90 SE

[G_Reaper]

Thanks for the response.
I had a good knowledge of the differences in the pistons and liners in the HC engine having had 1 and later an SE. I have recently been looking at a very very late non HC turbo and a little birdy told me that the very last of the non HC turbos also had 'Nickosil'liners. Can anyone shed some light on this.
Regards MIke

[lotusguy]

G_Reaper said: Thanks for the response.
I had a good knowledge of the differences in the pistons and liners in the HC engine having had 1 and later an SE. I have recently been looking at a very very late non HC turbo and a little birdy told me that the very last of the non HC turbos also had 'Nickosil'liners. Can anyone shed some light on this.
Regards MIke

Mike,

It's possible, Lotus frequently mixed components, especially toward the end of a model run, but in the case of the engine, I doubt it. Due to the different timing and valve MOP required by the HC engine, I doubt that the engine number wouldn't indicate it as an HC engine if it had the nikosil hardware. Happy Motoring! Jim'85TE