Compression Ratio

[LongBaz463BHP]

I understand that the 5ltr is 10.5 However on my block is says 9.35 Is this just the block they used to make a 5ltr ?

[carsy]

Yes.

[Pupp]

10.5:1? Yeah right

[OleVix]

Pupp said:

10.5:1? Yeah right

whaddaya know! Is it lower than 10:1?

[DangerousDerek]

Need to measure stuff up Baz.
As Pupp suggests very unlikely as high as 10.5.
I reckon 9.35:1 would be where you want to be for your turbo.
But as said you need to properly check all components. Then cam choice comes into play.

[ianwayne]

4.0 and 5.0 litres both 10:1 according to owners booklet. The 450 is 9.5:1.

[Sardonicus]

ianwayne said:

4.0 and 5.0 litres both 10:1 according to owners booklet. The 450 is 9.5:1.

I would say the 500 is the highest of the lot and thats not much both 400 and 450 are nearer the late 8's in IMO and not the stamped 9.35 this info is from people that have actually checked rather than guesstimations

[macdeb]

450 is 8.9:1
pay no attention to either what is in handbook or indeed what is stamped on the block.

Edited by macdeb on Monday 27th July 07:11

[Bassfiend229hp]

macdeb said:

450 is 8.9:1
pay no attention to either what is in handbook or indeed what is stamped on the block.

Bloody typical really then ... nothing with a Tiv is what it says it is.

[Sardonicus]

Thing is Phil the quoted CR is Land Rovers fault this goes on quite a bit Fords old school 4's and V6's CR's were never what they stated either machine tolerances etc but these RV8 ones a bit wide for that I actually found the machine tolerances quite good for a production engine so cant go with that being the cause IMO, maybe mine was a good one and maybe if I did more that opinion would change so I just think it was a figure that was probably on the blue prints and LR just turned things down on the tooling/machining lets face it low CR never did any harm and if you consider area's of poor fuel quality globally etc maybe LR was just playing safe and didnt want loads of engine returns due to piston damage etc

Edited by Sardonicus on Monday 27th July 10:08

[macdeb]

^^^^ plus cut outs in pistons etc.