Thread: e10,91,95,98 for d2 v8

Yes.

And re the CR using 98. The compression ratio where 98 is required depends on many things , including most importantly the combustion chamber shape.

In an RV8 the combustion chamber shape is 1961 high tech so needs a much higher octane at a given compression ratio than engines designed in say 2000s eg GM Gen IV which runs 10.5 to 11.2 :1 on 98.

The camshaft design and duration also affects this, as do the installation of knock sensors , and sequential injection.

But from the many posts on here complaining of excessive pinging over time, the 9.34:1 Vs 8.313:1 low comp, the 9.34:1 should use 98.

Although I must admit that LR compression ratios seem to be about as factual as Game of Thrones.
Regards Philip A

You mean GOT isn't real?

Originally Posted by PhilipA

Yes.

And re the CR using 98. The compression ratio where 98 is required depends on many things , including most importantly the combustion chamber shape.

In an RV8 the combustion chamber shape is 1961 high tech so needs a much higher octane at a given compression ratio than engines designed in say 2000s eg GM Gen IV which runs 10.5 to 11.2 :1 on 98.

The camshaft design and duration also affects this, as do the installation of knock sensors , and sequential injection.

But from the many posts on here complaining of excessive pinging over time, the 9.34:1 Vs 8.313:1 low comp, the 9.34:1 should use 98.

Although I must admit that LR compression ratios seem to be about as factual as Game of Thrones.
Regards Philip A

Mine reads 9.35:1 and the other guy mentioned earlier that his reads 9.38:1 and now your saying there's a 9.34:1 how many high compression motors are there???

There is only one spec AFAIK.
I had a Google of Thor and the only reference I could find was 9.34.

Now you or the other poster may have read the last digit incorrectly so your two may be the same and my UK forum reference incorrect.

BUT do you realize how small a difference of 0.01 to one is?

It is maybe a tiny sliver of material, and in any case the chamber are cast so they are all over the place anyway and may vary by lots more than 0.01 to one, more like 0.1 to one.

Darn I knew there would be a bush lawyer somewhere who would quibble over 0.01 to one CR , so I looked it up over several sites including the RAVE page.

To find your actual CR to probably about 0.1 you will have to get a burette and measure the combustion chamber, calculate the thickness of the head gasket, and work out the volume from the bore ( and you will be wrong because the gasket may not come exactly to the bore), and somehow calculate the bowl volume including the area above the piston and down to the ring land.
I have had a go at it and obtained a result using Kero, a sheet of Perspex, and some plasticine but it was probably only accurate to about 0.5 or so.
Regards Philip A

Originally Posted by PhilipA

There is only one spec AFAIK.
I had a Google of Thor and the only reference I could find was 9.34.

Now you or the other poster may have read the last digit incorrectly so your two may be the same and my UK forum reference incorrect.

BUT do you realize how small a difference of 0.01 to one is?

It is maybe a tiny sliver of material, and in any case the chamber are cast so they are all over the place anyway and may vary by lots more than 0.01 to one, more like 0.1 to one.

Darn I knew there would be a bush lawyer somewhere who would quibble over 0.01 to one CR , so I looked it up over several sites including the RAVE page.

To find your actual CR to probably about 0.1 you will have to get a burette and measure the combustion chamber, calculate the thickness of the head gasket, and work out the volume from the bore ( and you will be wrong because the gasket may not come exactly to the bore), and somehow calculate the bowl volume including the area above the piston and down to the ring land.
I have had a go at it and obtained a result using Kero, a sheet of Perspex, and some plasticine but it was probably only accurate to about 0.5 or so.
Regards Philip A

Hahaha all good man im not having a go at ya I was just thinking well I dont know these engines and as unlikely as it sounds I had to ask how many varients there were in high cr

one.