View Poll Results: Will polishing the inside of an intake manifold improve performance?
Yes, it will improve performance
0
0%
No, it won’t do anything at all
3
100.00%
No, it will reduce performance
0
0%
Voters: 3. You may not vote on this poll
D17VTECPOWER threads consolidated - how a member should not behave
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Rep Power: 118 Why VTEC and non VTEC pistons?
I have searched for this out of curiosity and I haven’t found anything. But why would Honda go through the expense of designing 9.9:1 compression pistons for the D17A and D17A2, but use 9.5:1 compression pistons in the D17A1 and D17A6? It’s not like there is any measurable difference in performance or gas mileage between the two, so why would they bother? If they could get away with 9.9:1 pistons on the D17A2 with no problems, why wouldn’t they do it on all the D17 engines? I just don’t get it.
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Re: Why VTEC and non VTEC pistons?
It’s not like there is any measurable difference in performance
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Rep Power: 222 Re: Why VTEC and non VTEC pistons?
The change in compression is a good chunk of what makes the difference in power. Basic engine math
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Rep Power: 118 Re: Why VTEC and non VTEC pistons?
Even if the relation between compression ratio and horsepower were linear, which it isn’t, you’d still only gain 4% power. The 10 HP difference is also caused by VTEC, different exhaust, different header, different cam, and probably other things that I’m not thinking of also. Compression isn’t the only difference.
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Rep Power: 127 Re: Why VTEC and non VTEC pistons?
who knows, they use different algorithm for the ecu, fuel trims, its tied with emissions mpg ,.. diffrent valves , cam it all affects the end result... I am sure there was a reason...
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Re: Why VTEC and non VTEC pistons?
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I meant no real difference in performance between 9.5 and 9.9 compression.
You've been making threads about wanting to blow big balla dollas on insane tweeking for minuscule, nearly immeasurable gains in either RPM or HP.......and now here you are totally dismissing the absolute most basic fundamental time honored method of increasing power.....?
Have another blast, son.
Today I learned 10 horsepower is not a measureable difference.
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Rep Power: 118 Could carbon on pistons INCREASE performance?
I know that carbon in the combustion chamber of an engine increases its compression, possibly enough to cause knocking and pinging. But if an engine has enough carbon on the pistons to increase compression, but not enough to make it detonate, could the carbon theoretically improve the engine’s performance by raising compression? I understand that the carbon can effect the engine’s performance by restricting flow, preventing valves from sealing and things like that, but presuming that the carbon is only on the piston tops and cylinder head, could performance possibly be improved?
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Rep Power: 210 Re: Could carbon on pistons INCREASE performance?
I know that carbon in the combustion chamber of an engine increases its compression, possibly enough to cause knocking and pinging. But if an engine has enough carbon on the pistons to increase compression, but not enough to make it detonate, could the carbon theoretically improve the engine’s performance by raising compression? I understand that the carbon can effect the engine’s performance by restricting flow, preventing valves from sealing and things like that, but presuming that the carbon is only on the piston tops and cylinder head, could performance possibly be improved?
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Rep Power: 118 Re: Why VTEC and non VTEC pistons?
I am NOT going to change my pistons, I’m just curious. I don’t have the time or desire to tear my engine out and disassemble it again. And no, I didn’t tow the Civic home yet. I am going to tow the Civic home when the weather warms up.
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Bull. Butter.
You've been making threads about wanting to blow big balla dollas on insane tweeking for minuscule, nearly immeasurable gains in either RPM or HP.......and now here you are totally dismissing the absolute most basic fundamental time honored method of increasing power.....?
Have another blast, son.
Some spend a lot of money for even smaller gains.
You've been making threads about wanting to blow big balla dollas on insane tweeking for minuscule, nearly immeasurable gains in either RPM or HP.......and now here you are totally dismissing the absolute most basic fundamental time honored method of increasing power.....?
Have another blast, son.
Some spend a lot of money for even smaller gains.
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Rep Power: 210 Re: Could carbon on pistons INCREASE performance?
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Rep Power: 118 Re: Running rich- Please help!
Huh. Mine never set a code when the cam sensor was loose. I confirmed that the cam sensor was moving and causing the engine to die. I started the engine, set the handbrake, put it in D and wiggled the cam sensor with the engine idling. I could consistently kill the engine my moving it since it is loose, but it never set a code. Go figure. Maybe it never set a code because the sensor was electrically fine, but physically broken and moving around.
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If the dealership service techs couldn't answer that then I can't. Hopefully, someone else here can.
How did you narrow it down to the ECU as the issue?
