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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Re: Running rich- Please help!
I tried replacing the ECU with a VTEC ECU when I installed this engine, but the immobilizer wouldn’t flash, so I had to wire a switch for VTEC.
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Re: Could carbon on pistons INCREASE performance?
carbon build up can create hot spots in the combustion chamber and cause issues, yet another pointless idea
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Rep Power: 119 Re: Why VTEC and non VTEC pistons?
If it costs Honda just one cent less to make the lower compression piston vs the higher compression one.
times 4 pistons a car.
times millions of cars.
= one fat piggy bank
Economics is often reason why on a mass produced item.
times 4 pistons a car.
times millions of cars.
= one fat piggy bank
Economics is often reason why on a mass produced item.
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Rep Power: 119 Re: Why VTEC and non VTEC pistons?
Last edited by D17VTECPOWER; Feb 9, 2018 at 10:32 AM.
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Rep Power: 210 Re: Why VTEC and non VTEC pistons?
Makes sense, but why would it cost Honda less to make higher compression pistons? Do they take more material to make? My consperiacy theory is that car companies use their highest quality parts, even within the same part number, on more expensive cars. So maybe the D17A1 rods are the “rejects” from the D17A2 that wouldn’t perform as well in a higher power engine, like “binning” computer parts.
My guess would be that the different pistons or compression ratios may help make emissions or fuel economy standards. Either of these can have big consequences.
I would also point out that your idea about 'rejects' and grading parts would require testing that could double the cost of the parts not to mention keeping track of separate parts with no visible difference.
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Rep Power: 211 Re: Could carbon on pistons INCREASE performance?
If I'm wrong I apologize to him in advance.
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Rep Power: 368 Re: Why VTEC and non VTEC pistons?
dude...
one engine have the VTEC, the other don't. Because they wanted to call it the "sport" version. The VTEC system alone is way more complicated and costly. why are you enven saying that about the pistons?
There's the sun roof (so the chassis will have a cut on the roof), there's the seats with arm rests, etc, etc. Changing the pistons is just small change in comparison!!!!
small field of vision, really.
one engine have the VTEC, the other don't. Because they wanted to call it the "sport" version. The VTEC system alone is way more complicated and costly. why are you enven saying that about the pistons?
There's the sun roof (so the chassis will have a cut on the roof), there's the seats with arm rests, etc, etc. Changing the pistons is just small change in comparison!!!!
small field of vision, really.
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Rep Power: 119 Re: My brakes don't work right
Yes, you won. Not sure what you won though. I adjusted the brakes way loose. I tightened the adjustment, and the pedal feels more firm. However, I think I still have a problem. When I was putting the wheel on, I had an assistant hold the brake pedal so I could tighten the lug nuts. However, I could still turn the back wheels with a breaker bar with someone pushing the brake pedal, although there was a bit of resistance. And yes, I assembled everything correctly, and I used OEM Honda wheel cylinders, brake shoes and hardware. Any ideas?
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Rep Power: 519 Re: My brakes don't work right
I had an assistant hold the brake pedal so I could tighten the lug nuts. However, I could still turn the back wheels with a breaker bar with someone pushing the brake pedal
Also, use a torque wrench to tighten lugs, not a breaker bar. 80 ft-lb.
Pull the handbrake. Does it feel right now?
Can you skid the rear tires using the handbrake?
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Rep Power: 119 Re: Running rich- Please help!
I installed the new cam sensor, and the engine runs perfect again. However, the fuel trim is still way negative. Any ideas? I think I'm going to rent a gauge and check the fuel pressure next.
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Rep Power: 223 Re: Running rich- Please help!
tl;dr
Why wrong sensor? Which exhaust manifold are you using?
Which injectors are you using?
How long has this been a problem?
What fault code did it set? (no code? no problem.)
If it has NOT coded that means the ECM is still controlling fuel delivery within its programmed fuel trim ranges. No problem?
Take a reading of MAP voltage with the engine at fully warmed up idle, all electric loads turned off. What's the voltage reading?
Why wrong sensor? Which exhaust manifold are you using?
Which injectors are you using?
How long has this been a problem?
What fault code did it set? (no code? no problem.)
If it has NOT coded that means the ECM is still controlling fuel delivery within its programmed fuel trim ranges. No problem?
Take a reading of MAP voltage with the engine at fully warmed up idle, all electric loads turned off. What's the voltage reading?
......
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Rep Power: 119 Re: Running rich- Please help!
I just checked the MAP sensor voltage with the engine fully warmed up and idling in neutral with all loads off like I was told to, and the MAP voltage is 1.1 volts at idle, which seems normal to me. With the engine off and key on, the MAP voltage is about 2.8, which also seems normal to me. Any other ideas?
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Rep Power: 119 Re: Running rich- Please help!
No. But I don’t think that the injectors are leaking. If I pull the fuel line off the rail after the car sits overnight, there is still a little pressure on the system, so I don’t think the injectors are leaking. High fuel pressure keeps coming to mind, but I haven’t tested the fuel pressure yet.
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Rep Power: 519 Re: Running rich- Please help!
I just checked the MAP sensor voltage with the engine fully warmed up and idling in neutral with all loads off like I was told to, and the MAP voltage is 1.1 volts at idle, which seems normal to me.
1.1v is too high.
Ideally, I like to see 0.80-0.90v....
Adjust valves , tight valves can cause it
Have you checked cam timing?
Check EGR position, if it is slightly open or leaking that can cause it
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Rep Power: 119 Re: Running rich- Please help!
My altitude is 350 feet above sea level, so pretty low. I just adjusted my valves before taking the reading, so the valve adjustment is correct. The EGR is blocked off for now, so it can't be leaking. Any other ideas?
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Rep Power: 519 Re: Running rich- Please help!
Cam gear indexing off?
false read of MAP value, for some reason?
I'm at around 600-700 ft above sea level
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Rep Power: 119 Re: Running rich- Please help!
Maybe my multimeter is not accurate, I'll try a different multimeter. I don't suspect a cam timing issue because the engine runs so darn good, but I guess it's possible.
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Rep Power: 519 Re: Running rich- Please help!
OTOH if the cam becomes retarded by a tooth it's usually real noticeable.
jumping 2 teeth or more can cause some PCMs to shut the engine down due to cam-crank signals too far out of sync...
