Issues after cam/ heads install
01-26-2018, 11:58 AM
#22
Melting Slicks
I was foolish enough to believe the same thing, until we ran my car with 102 octane at 16° total timing and it still knocked! It was clearly false knock. My tuner who is a well known Turner, I won't say his name, said he couldn't get out that's just the way these motors are. And then took it to Michael at serious horsepower and he turned each cylinder individually and got rid of the false knock. it took him 3 to 4 hours but he was able to do it, and I gain 15 hp and 20 pounds of torque.
01-26-2018, 12:24 PM
#23
Unless we are talking about changing the spark plug gap as a measure of individual cylinder tuning...the stock ECM does not support individual cylinder tuning. If a tuner actually said "individual cylinder tuning" outloud I would be very curious what was meant. Sounds like a case of BS.
He may have been talking about knock sensor setttings. There’s tables in the pcm that show knock sensor sensitivity for each cylinder. How it works being that the sensors are at the base of the engine I have no idea lol
01-26-2018, 12:32 PM
#24
I did the cam install. Car had 0 knock when it left our shop. It made almost identical numbers as before when we tuned it. I'm 99.9% sure the cam is installed correctly without too much advance. I'm also 99.9% sure AHP cc's their heads and there isn't a chance that the heads got milled twice. I believe either the car is picking up false Knock from another source or it possibly has some bad fuel. If I can be of help with resolving your issue Phillip let me know.
01-26-2018, 12:47 PM
#27
If its truly detonating like they think, Have them do a wot pull, or where the car is detonating at, shut the car off Immediately after the pull and pull the spark plugs. Detonation will Always show up on a plug.
Last edited by Twinscrew; 01-26-2018 at 12:55 PM.
01-26-2018, 01:36 PM
#30
I would put in new plugs, (BR7EF) these are cheap, and see if that changes anything. If it is still detonating, I would pull the plugs and see what they look like.
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Twinscrew (01-26-2018)
01-26-2018, 01:48 PM
#31
Team Owner
If that cam is listing specs for 1.7 rockers rather than our 1.8 rockers...your actual lift numbers are .678 / .668 If so, that's an aggressive cam.
Last edited by MTPZ06; 01-26-2018 at 01:50 PM.
01-26-2018, 02:42 PM
#33
I doubt it is the heads. .030" mill is fine, I've never seen issues unless you pick a really crappy cam, combine that with a really thin head gasket, or have really crap gas.
Was the gas good? That is first place to check. Then mechnical issues. False knock can be something banging around, or even something like pushrods wrong size/etc. I don't know if I would jump to pulling a head until everything else is sorted out. Could just be a loose bolt, or bad sensor.
Headers don't cause false knock unless they are banging on something.
And tuning each cylinder individually, please tell more. What aftermarket ECU do you have that allows that?
Was the gas good? That is first place to check. Then mechnical issues. False knock can be something banging around, or even something like pushrods wrong size/etc. I don't know if I would jump to pulling a head until everything else is sorted out. Could just be a loose bolt, or bad sensor.
Headers don't cause false knock unless they are banging on something.
And tuning each cylinder individually, please tell more. What aftermarket ECU do you have that allows that?
01-26-2018, 05:23 PM
#34
Team Owner
It has tables for it but as soon as you touch them everything goes to ****.
01-27-2018, 12:17 AM
#36
Le Mans Master
I'd pull your car from that shop and get a second opinion before I'd let them tear it apart. Seems like a bunch of bologna to me. Even IF they were milled twice or more than .030" you should not have any issue tuning your car on 93 octane.
01-27-2018, 08:54 AM
#37
Did a ride along yesterday and you can definitely hear a flutter-like noise when the car is tuned to its max power, with around 22 deg. of timing, at WOT. When we dropped the timing to 10 deg, we couldn't hear the noise. I'd heard that noise before but didn't realize what it was, I'd always thought it was a slight rattle in the dash or shifter. Shop is convinced it's detonation and they know way more than me. The shop showed me the dyno sheets too, and the best they could get was 518/470. Something has to be wrong for the power to be that low, even if it is false knock, right? I think the first thing they're gonna do is pull one head and CC it and go from there.
Last edited by ncsurveyor2007; 01-27-2018 at 08:54 AM.
01-27-2018, 09:00 AM
#38
Just got me worried/ kinda sick because the car only has 13000 miles and was bone stock before I decided to do anything to it. It's gotta be something to do with the heads or the cam right? That's basically all that's changed on the car and ive NEVER ran it hard, before or after the work. I wonder if the cam could have been ground wrong?
Last edited by ncsurveyor2007; 01-27-2018 at 09:02 AM.
01-27-2018, 09:43 AM
#39
Safety Car
Did a ride along yesterday and you can definitely hear a flutter-like noise when the car is tuned to its max power, with around 22 deg. of timing, at WOT. When we dropped the timing to 10 deg, we couldn't hear the noise. I'd heard that noise before but didn't realize what it was, I'd always thought it was a slight rattle in the dash or shifter. Shop is convinced it's detonation and they know way more than me. The shop showed me the dyno sheets too, and the best they could get was 518/470. Something has to be wrong for the power to be that low, even if it is false knock, right? I think the first thing they're gonna do is pull one head and CC it and go from there.
01-27-2018, 09:47 AM
#40
Safety Car
Correct, he said the computer can see each cylinder and where the knock is coming from and he could focus on those points in the tune to remove it without playing with the sensitivity of the knock sensor. That's how he explained it to me.