Can't get my tune down, 09 si usdm

Calibrations for FlashPro Manager - Use all calibrations at your own risk (dyno tuning recommended)

jcoul72
Posts: 52
Joined: Wed Jun 16, 2021 1:41 pm

Re: Can't get my tune down, 09 si usdm

Post by jcoul72 »

The timing gears were never removed from the cams, and the chain marks were aligned before torquing it down, so I imagine the motor is still in time. The front bumper is still off so maybe I'm just hearing more induction noise.

I think we should try lowering the knock sensitivity, then reevaluating. If the knock is actually real, do you think I would be able to hear it through a set of knock ears? Also you don't come off as rude to me so no worries.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Can't get my tune down, 09 si usdm

Post by EFICU »

Ok gotcha. I was thinking if they moved then it could throw off the timing delivered. By lowering the knock sensitivity, all we're doing is basically making the knock sensor less sensitive to noise. That way it would need more noise to register a knock essentially. You would have to be comfortable with it being false knock, because this wouldn't remove knock, just make the sensor require more audible noise to register a knock and therefore drowning out the noise it hears now. And in the hopes that if a real knock occurs in the future, it might still hear it. I try to creep up on the limit to drown out false noise in the hopes it might hear a real one in the future, but there is no way to say.

Yes if you know someone who has audible knock equipment that would great. It's rare in the real world that someone has them, but if you can find them yes. I always try to be very cautious with other people's car, which is why the potential for false knock is always so tough for me. And the only problem with it registering knock too, is that I leave all the factory protections in place as intended. So if it registers knock, it raises the knock control value which causes more proactive timing reduction. Hence why you see 8* or more ignition being pulled by the ECU to try to protect the engine. Some guys bypass the knock control, and even the ignition retard completely, but I don't. That's why if you believe it to be false knock, the sensitivity tables make for a better long term solution. That and I only adjust the cells where the knock occurs on the sensitivity tables, leaving any not impacted by the false knock to remain OEM for future knock protection.
jcoul72
Posts: 52
Joined: Wed Jun 16, 2021 1:41 pm

Re: Can't get my tune down, 09 si usdm

Post by jcoul72 »

Sweet, let's do it. Also I will recheck my valve lash again in the new year, because I don't believe it should be this noisy.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Can't get my tune down, 09 si usdm

Post by EFICU »

Okay. Let me look over that last datalog and study where it’s happening. That way I’m only adjusting the cells registering knock.

Also, when you do check the valves clearance again, we’ll try it again with OEM sensitivity tables to see if knock registers. If it doesn’t register knock then, or more realistic numbers, we’ll go from there.
jcoul72
Posts: 52
Joined: Wed Jun 16, 2021 1:41 pm

Re: Can't get my tune down, 09 si usdm

Post by jcoul72 »

Sounds good. Question, if the timing chain somehow was off, would the ecu throw a code?
jcoul72
Posts: 52
Joined: Wed Jun 16, 2021 1:41 pm

Re: Can't get my tune down, 09 si usdm

Post by jcoul72 »

Also, could a coilpack be going bad without tripping a code? I'm thinking since one had to be replaced recently, that the others may not be far behind. I ask this because while I suspect that the difference in engine note could be the combination of no bumper + timing retard, I want to make sure it's not poor ignition quality.
EFICU
Posts: 3295
Joined: Mon Feb 25, 2019 10:14 pm

Re: Can't get my tune down, 09 si usdm

Post by EFICU »

jcoul72 wrote: Sun Dec 19, 2021 7:18 am Sounds good. Question, if the timing chain somehow was off, would the ecu throw a code?
Not usually as far as I understand it. I guess I was technically wrong in my previous post in that the ignition wouldn't be advanced from the cams being advanced. But there still could be an issue there is all if they are advanced.
jcoul72 wrote: Sun Dec 19, 2021 7:51 am Also, could a coilpack be going bad without tripping a code? I'm thinking since one had to be replaced recently, that the others may not be far behind. I ask this because while I suspect that the difference in engine note could be the combination of no bumper + timing retard, I want to make sure it's not poor ignition quality.
It can go bad without throwing a code, yes. You can swap the coils from 1 and 4, with cylinder 2 and 3, then retest. Cylinders 2 and 3 are the closest to the knock sensor, but swapping those coils with 1 and 4 would allow you to test for that issue. If the knock remains in 2 and 3, it's another issue. If the knock follows the coils, then they would be bad. Yeah it's hard to pinpoint with so many changes, including the head gasket replacement.
jcoul72
Posts: 52
Joined: Wed Jun 16, 2021 1:41 pm

Re: Can't get my tune down, 09 si usdm

Post by jcoul72 »

The knock count issue ended up being bad valve lash, and the motor was also improperly timed. I fixed those issues and was good until I discovered a hairline crack in the block.

Now I have replaced the k20 w a k24a4 w piston oil squirters and oil cooler added. The specs are as follows:

K24a4 block
K20z3 cylinder head
12.5:1 compression pistons
Scat rods
Fully balanced rotating assembly (k24a2 crank)
Drag Cartel Drop-in cams
72mm throttle, portmatched RBC manifold
Same plm design header as last time but the k24 version
DW 1000 injectors
DW fuel pump
K20a2 oil pump

I really need to have a basemap so I can drive the car down to the dyno, if you don't mind helping once again. Thanks
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