Running Lean and Knock

[stevetalon]

Ok I just put in my keydiver chip and im getting 25 knock counts at wot and my wideband is reading around 12.4-13.1 at wot. Is this to lean and if my timing is off, could this cause me to knock?

 

[spooln4fun]

25 counts To answer one question if your timing is off then yes it will affect it. For the lean condition I consider 14:x and above to lean for my self

 

[Loewen21]

25 counts To answer one question if your timing is off then yes it will affect it. For the lean condition I consider 14:x and above to lean for my self

I'm not sure what kind of magic car you drive, but on stock DSMs at wot you get about a 9:1. Most people i've heard from run a safe 11.5 usually or lower. I have heard of some people leaning out up to 12.5 but you really have to know what you're doing for that. So yes, your car is definitely knocking because of the lean condition.

 

[stevetalon]

whats wierd is i wasn't getting any knock on the stock ecu i had right before i put the chipped ecu in
im only on 13 pounds on my t28 and i recently put a new fuel filter in
If i were to get a safc do i have fuel to add on stock pump and stock 450cc

 

[Demon33]

Ok I just put in my keydiver chip and im getting 25 knock counts at wot and my wideband is reading around 12.4-13.1 at wot. Is this to lean and if my timing is off, could this cause me to knock?

I don't see a fuel pump, injectors or AFPR in your profile. What boost level are you running? The stock injectors on the stock fuel pump will be too small for a t28 beyond about the stock boost level. What are your injector duty cycles? Even with the keydiver chip, you could be running lean if your IDC are too high due to the injectors and pump being too small for the airflow /boost level. This could cause you to knock. If you have a way to tune, I would try to shoot for about 11.0-11.5 AFR on pump gas with IDC of about 85% to be on the safe side and watch for knock as you are doing.

Also, your ignition timing could be playing a role in the knock you're experiencing. Before I installed the methanol injection kit in my car I couldn't run anything past 18 PSI boost without experiencing about 20-25 counts of knock on 91 pump gas at WOT on a e316g. AFRs were about 10.5:1 which is rich. I couldn't lean it out anymore without increasing the knock so I had to back my timing down by about 3 degrees from 5 degrees BTDC to about 2 degrees BTDC. This helped A LOT with the knock I was getting, but it also reduced the throttle response and my fuel mileage.

After my alcohol injection kit, I've been able to increase the timing back to stock at 5 degrees BTDC, increased my boost to 25 PSI, leaned out my AFR to about 11.1:1 and gained back my fuel mileage all on 40/60 alcohol/water mix.

Like I said, run it richer than you are now to about 11.0-11.5:1 and see if this helps. If not, you can go richer and/or reduce your base timing a couple of degrees. Or like I eventually did, run an alcohol injection kit and get the best of both.

Hope this helps. Good luck.

 

[stevetalon]

Is there a cheap way to add more fuel? im only running 13psi on the t28.
What could cause my car to be so lean? o and the chip is set for a 10.5:1 ratio

 

[awdmonster1904]

whats wierd is i wasn't getting any knock on the stock ecu i had right before i put the chipped ecu in
im only on 13 pounds on my t28 and i recently put a new fuel filter in
If i were to get a safc do i have fuel to add on stock pump and stock 450cc

upgrade your fuel pump get a afpr if money is tight get a SAFC and you can add fuel that way
you also have to check for boost leaks and check your logs for phantom knock
you also have to take in mind that the keydiver chips are set for a car with a base fuel pressure you asked jeff for(keydiver) compression MAF fuel pump
those are all factors that you have to take in mind
If your chip has setings where you have to have a 2g maf and you are still on 1g maf its going to mess things up that goes for all other setting
check what kind of fetures does your chip have first

Is there a cheap way to add more fuel? im only running 13psi on the t28.
What could cause my car to be so lean? o and the chip is set for a 10.5:1 ratio

check your chip try to be more espesific on your mods so we can help you your info really vauge