msd 2 step, efi afr with tb
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From: Broken Arrow, OK
msd 2 step, efi afr with tb Hello Gents,
quick question for you.
I am using a MSD 2 step and have been trying to get it perfect. I have a trans brake and efi live with LC1 wide band. When the 2 step is active and I can see boost building, my afr starts to go lean (13/14 to 1) I know this is kind of a normal reading on the WB when there is a miss, but should I be trying to put more fuel in anyway? I am also seeing knock when the 2 step is active and making some boost.
Please help me to increase my wisdom o knowledgable ones of the FI world.
quick question for you.
I am using a MSD 2 step and have been trying to get it perfect. I have a trans brake and efi live with LC1 wide band. When the 2 step is active and I can see boost building, my afr starts to go lean (13/14 to 1) I know this is kind of a normal reading on the WB when there is a miss, but should I be trying to put more fuel in anyway? I am also seeing knock when the 2 step is active and making some boost.
Please help me to increase my wisdom o knowledgable ones of the FI world.
I let my fueling alone on the two step and it usually shows 13.5:1. You need to figure out if you knock is real or false due to the two step causing the engine/car to shake. I have zero knock on my two step and run around 30 degrees of timing, but I am on e85.
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From: Broken Arrow, OK
Does more timing help to spool the turbo up? I am auto with a tight converter, so I can't get my rpm up very high. I think about 2800 to 2900 on the brake.
More timing (to a point) helps because it creates more torque, more torque means the converter will stall higher, which means you should be able to make more boost. The more boost you make, the more torque you make, the higher the stall goes, more torque, more boost, etc.
I'm not sure how the 2 step functions on an auto (in a manual car it helps to ignite the mixture in the exhaust by retarding timing), but it seems like it just holds the engine at a given rpm and lets it build as much boost as possible for that amount of load.
The key to everything is having a stall that lets you get high enough to start the process. The looser the stall, the quicker the process happens. If the stall is too tight or the setup laggy, you'll never start the process and the 2 step won't help.
How much boost are you building at 2800? If not much you might be able to spool faster by insulating your hot parts (coatings, wrap, blankets).
I'm not sure how the 2 step functions on an auto (in a manual car it helps to ignite the mixture in the exhaust by retarding timing), but it seems like it just holds the engine at a given rpm and lets it build as much boost as possible for that amount of load.
The key to everything is having a stall that lets you get high enough to start the process. The looser the stall, the quicker the process happens. If the stall is too tight or the setup laggy, you'll never start the process and the 2 step won't help.
How much boost are you building at 2800? If not much you might be able to spool faster by insulating your hot parts (coatings, wrap, blankets).
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is your 2 step set at 2800-2900?
can you look and see where your timing is at at that point?
and incase i missed it what size is the ar of your turbo.
im about to loosin my tight converter up but at 2300rpm on the 2 step (no trans brake) i can get 3lbs in just a second
can you look and see where your timing is at at that point?
and incase i missed it what size is the ar of your turbo.
im about to loosin my tight converter up but at 2300rpm on the 2 step (no trans brake) i can get 3lbs in just a second
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From: Broken Arrow, OK
is your 2 step set at 2800-2900?
can you look and see where your timing is at at that point?
and incase i missed it what size is the ar of your turbo.
im about to loosin my tight converter up but at 2300rpm on the 2 step (no trans brake) i can get 3lbs in just a second
can you look and see where your timing is at at that point?
and incase i missed it what size is the ar of your turbo.
im about to loosin my tight converter up but at 2300rpm on the 2 step (no trans brake) i can get 3lbs in just a second
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From: Broken Arrow, OK
This is what I did to determine what stall speed I needed to build boost with the 2 step and transbrake. Try this.
Put the trans in neutral, set the 2 step for 3000rpm, drop timing to 10 degrees(to symulate load), activate the 2 step and stand on it (in neutral) and see if you build any boost. The car should pop and bag out the exhaust, this is normal. Then turn the 2 step up 200 or more rpm and try it again. Do this until you find were it builds boost as fast as you want. My 408 with rear mounted GT-88, 2 step in netraul with 10 degrees of timing builds 6+psi within 1.5 seconds at 4500rpm. I sent my convertor back to Circle D to have it set up for 4500rpm. Good Luck.
Put the trans in neutral, set the 2 step for 3000rpm, drop timing to 10 degrees(to symulate load), activate the 2 step and stand on it (in neutral) and see if you build any boost. The car should pop and bag out the exhaust, this is normal. Then turn the 2 step up 200 or more rpm and try it again. Do this until you find were it builds boost as fast as you want. My 408 with rear mounted GT-88, 2 step in netraul with 10 degrees of timing builds 6+psi within 1.5 seconds at 4500rpm. I sent my convertor back to Circle D to have it set up for 4500rpm. Good Luck.
This is what I did to determine what stall speed I needed to build boost with the 2 step and transbrake. Try this.
Put the trans in neutral, set the 2 step for 3000rpm, drop timing to 10 degrees(to symulate load), activate the 2 step and stand on it (in neutral) and see if you build any boost. The car should pop and bag out the exhaust, this is normal. Then turn the 2 step up 200 or more rpm and try it again. Do this until you find were it builds boost as fast as you want. My 408 with rear mounted GT-88, 2 step in netraul with 10 degrees of timing builds 6+psi within 1.5 seconds at 4500rpm. I sent my convertor back to Circle D to have it set up for 4500rpm. Good Luck.
Put the trans in neutral, set the 2 step for 3000rpm, drop timing to 10 degrees(to symulate load), activate the 2 step and stand on it (in neutral) and see if you build any boost. The car should pop and bag out the exhaust, this is normal. Then turn the 2 step up 200 or more rpm and try it again. Do this until you find were it builds boost as fast as you want. My 408 with rear mounted GT-88, 2 step in netraul with 10 degrees of timing builds 6+psi within 1.5 seconds at 4500rpm. I sent my convertor back to Circle D to have it set up for 4500rpm. Good Luck.
To get the converter right you need someone who is familiar with setting up converters for turbo setups to get you in the ball park and then start adjusting it.
