ninjette.org - View Single Post - Fuel injected 08-11 ninja250r help

DannoXYZ · September 12th, 2021, 02:36 PM

Knock-sensors don’t work at high-RPMs and high-loads because of valvetrain noise. Too many boosted engines have blown up due to reliance on knock-sensor.

It takes A LOT of filtering and signal-processing to detect knock from sensor signal. Only product that actually kinda works is J & S http://www.jandssafeguard.com . Based on Porsche’s KLR which is basically boost-controller/ignition piggyback that lowers boost and retards ignition when it detects knock.

But even then, many have blown up engines with this system since knock is so extremely difficult to detect at high RPMs. Porsche’s maps are extremely conversative and stays far, far away from knock region, so sensor is really backup safety measure for worse-case scenarios of super hot days and bad petrol. I can extract +100bhp from Porsche turbo engine by just tweaking maps alone! But you risk blown-up engine being that close to edge of destruction!

Best signal-processor to detect knock is human brain!!!
https://linkecu.com/tech-articles/knockblock-explained/
https://tunertools.com/products/link-g4-knock-block
I have used devices that detect knock and blinks lights along with datalogging knock counts. Nope, not as good as human ears! I can pick it up on dyno runs before any device signals knock. You’ll want to tune on dyno as there’s just too much extra noise out on road. And you can’t safely focus sufficient attention on engine noises if you have to worry about riding bike at +100mph and watching out for traffic.

Best to tune on dyno based upon BMT - best mean (ave) torque output. Start with conservative ignition settings first, then gradually advance ignition. Look at dyno chart and notice how much TQ increases for each degree of advance. Best settting is when you notice TQ no longer increases at same rate when ignition is advanced another degree. Then back off a degree. This approach is way, way safer than having way too much ignition-advance like you have now. Start around 30-degrees in high-load range.

This also gives you richer AFR as well. BTW, how are you measuring AFR? Hopefully not with O2-sensors that came with Ecotrons kit! You’ll want to target 11.5:1 under high-loads for boosted engines. Doesn’t sacrifice any power, but much, much safer for engine. Here’s good discussion on tuning ignition maps: https://www.msextra.com/forums/viewt...p?f=94&t=26725

Basic tuning guide: http://www.megamanual.com/ms2/tune.htm

i’ve downloaded your Procal file, I’ll see if I can tweak it. Perhaps import EU N250/N300 EFI ignition maps as baseline. You really need to get larger injectors, VE table is simply trying to compensate for too-small injectors and it’s not accurate. What pump are you using and what is its flow-rating?

September 12th, 2021, 02:36 PM	#31
DannoXYZ ninjette.org certified postwhore Name: AKA JacRyann Location: Mesa, AZ Join Date: Dec 2011 Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C Posts: A lot. MOTY - 2018, MOTM - Nov '17	Knock-sensors don’t work at high-RPMs and high-loads because of valvetrain noise. Too many boosted engines have blown up due to reliance on knock-sensor. It takes A LOT of filtering and signal-processing to detect knock from sensor signal. Only product that actually kinda works is J & S http://www.jandssafeguard.com . Based on Porsche’s KLR which is basically boost-controller/ignition piggyback that lowers boost and retards ignition when it detects knock. But even then, many have blown up engines with this system since knock is so extremely difficult to detect at high RPMs. Porsche’s maps are extremely conversative and stays far, far away from knock region, so sensor is really backup safety measure for worse-case scenarios of super hot days and bad petrol. I can extract +100bhp from Porsche turbo engine by just tweaking maps alone! But you risk blown-up engine being that close to edge of destruction! Best signal-processor to detect knock is human brain!!! https://linkecu.com/tech-articles/knockblock-explained/ https://tunertools.com/products/link-g4-knock-block I have used devices that detect knock and blinks lights along with datalogging knock counts. Nope, not as good as human ears! I can pick it up on dyno runs before any device signals knock. You’ll want to tune on dyno as there’s just too much extra noise out on road. And you can’t safely focus sufficient attention on engine noises if you have to worry about riding bike at +100mph and watching out for traffic. Best to tune on dyno based upon BMT - best mean (ave) torque output. Start with conservative ignition settings first, then gradually advance ignition. Look at dyno chart and notice how much TQ increases for each degree of advance. Best settting is when you notice TQ no longer increases at same rate when ignition is advanced another degree. Then back off a degree. This approach is way, way safer than having way too much ignition-advance like you have now. Start around 30-degrees in high-load range. This also gives you richer AFR as well. BTW, how are you measuring AFR? Hopefully not with O2-sensors that came with Ecotrons kit! You’ll want to target 11.5:1 under high-loads for boosted engines. Doesn’t sacrifice any power, but much, much safer for engine. Here’s good discussion on tuning ignition maps: https://www.msextra.com/forums/viewt...p?f=94&t=26725 Basic tuning guide: http://www.megamanual.com/ms2/tune.htm i’ve downloaded your Procal file, I’ll see if I can tweak it. Perhaps import EU N250/N300 EFI ignition maps as baseline. You really need to get larger injectors, VE table is simply trying to compensate for too-small injectors and it’s not accurate. What pump are you using and what is its flow-rating? Last futzed with by DannoXYZ; September 13th, 2021 at 12:13 AM.