33 replies to this topic

[jeffster06]

Have new followers and a duplex adjustable timing kit. I knew about crank end float, forgot to mention that one. I am hoping to get the machine shop to calculate the compression ratio, or at least give me some of the base measurements needed for the calculation. What CR should I be aiming for? When I plug in the block serial number to the engine checker on guessworks site it shows factory was 10.1:1 I'm guessing I want to be around there? 

[Mini Manannán]

Have new followers and a duplex adjustable timing kit. I knew about crank end float, forgot to mention that one. I am hoping to get the machine shop to calculate the compression ratio, or at least give me some of the base measurements needed for the calculation. What CR should I be aiming for? When I plug in the block serial number to the engine checker on guessworks site it shows factory was 10.1:1 I'm guessing I want to be around there? 

I set my CR at 10:5:1.  It runs like a bag of spanners on 93RON but beautifully on 98RON

[jeffster06]

I set my CR at 10:5:1.  It runs like a bag of spanners on 93RON but beautifully on 98RON

We don't use RON in the states, best I can get easily is 93 Octane, which looks to be about 97.4 RON 

 

I also spoke with the machine shop they said they should be able to get within a tenth on the compression ration calculation, that sounds pretty close to me. 

[mikal]

Fuel octane is quoted in the USA as (RON+MON)/2 where RON is the Research Octane Number and MON is the Motor Octane Number (2 different types of Octane engines are used to obtain the results) whereas most other countries quote the RON number only. The RON of a fuel is always higher than the MON (a less harsh test).