Right so following on from the last thread (which I want to say thanks to all for the much needed advice!) I've been told that, the high compression 1.4 that I have got with the Nismo 0.5mm head gasket will have a compression ratio of around 10.2:1
I would really like to hit a higher figure of 11:1 and so have thoughts on taking the head off and skimming it around 0.8mm to reach this figure. However, I would still want the car to be a reliable source of power and not have to worry about blowing anything up. (The car would be going on standalone engine management (most likely a speeduino) and mapped on a rolling road.)
The engine has high lift cams 270deg and 9mm lift, and I remember reading one of Frank's earlier posts where he mentions that raising compression is a must if fitting wilder cams.
Here are the main concerns I have and so am wondering whether someone can help out please:
1. Is 11:1 going overboard or is this still a safe and reliable compression level to reach on a 1.4? Or should I be looking at going more than 11:1?
2. The engine is fresh fitted with a brand new Nismo head gasket and the engine has not been in a car since the gasket was fitted. Would it be okay to reuse this gasket when refitting the head back on?
3. I understand the lower chain will be slacker due to the reduced height. What effect will this have? The engine is on 75k-ish so its not exactly low miles but not too high mileage either.
I would really love to get people's thoughts on these 3 questions as it will help me quite a lot! I've wanted to do a head skim for quite a while but always had these sort of concerns but then I hear people on facebook say, 'just skim the block at a local machine shop for £40' and it sounds so tempting lol...
Would really appreciate any info/thoughts/advice etc.
I would really like to hit a higher figure of 11:1 and so have thoughts on taking the head off and skimming it around 0.8mm to reach this figure. However, I would still want the car to be a reliable source of power and not have to worry about blowing anything up. (The car would be going on standalone engine management (most likely a speeduino) and mapped on a rolling road.)
The engine has high lift cams 270deg and 9mm lift, and I remember reading one of Frank's earlier posts where he mentions that raising compression is a must if fitting wilder cams.
Here are the main concerns I have and so am wondering whether someone can help out please:
1. Is 11:1 going overboard or is this still a safe and reliable compression level to reach on a 1.4? Or should I be looking at going more than 11:1?
2. The engine is fresh fitted with a brand new Nismo head gasket and the engine has not been in a car since the gasket was fitted. Would it be okay to reuse this gasket when refitting the head back on?
3. I understand the lower chain will be slacker due to the reduced height. What effect will this have? The engine is on 75k-ish so its not exactly low miles but not too high mileage either.
I would really love to get people's thoughts on these 3 questions as it will help me quite a lot! I've wanted to do a head skim for quite a while but always had these sort of concerns but then I hear people on facebook say, 'just skim the block at a local machine shop for £40' and it sounds so tempting lol...
Would really appreciate any info/thoughts/advice etc.
