miataturbo.net-like debauchery thread (about the ND or something)
#575
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Actually DI is kind of like lowering intake temps. Well intake temps will be the same but since you are not compressing fuel and air in the combustion chamber preignition only occurs if fuel timing is too soon. Or that's the theory anyway.
Tons of potential for tuning with DI. Especially with dual variable cams. Now you don't have to squirt fuel before/during intake valve opening for it to be useful. You could squirt a little near TDC and maybe a little more with the piston on the way down. Or while the exhaust valve is open. Wanna keep your turbo spooled off throttle? Of course just speculating here but most of this thread has been just that.
Tons of potential for tuning with DI. Especially with dual variable cams. Now you don't have to squirt fuel before/during intake valve opening for it to be useful. You could squirt a little near TDC and maybe a little more with the piston on the way down. Or while the exhaust valve is open. Wanna keep your turbo spooled off throttle? Of course just speculating here but most of this thread has been just that.
#577
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Yep! You are talking about a "stratified" injection. Basically you get to inject right when you want ignition, thus avoiding detonation. The regular type of injection is commonly known as homogenious injection. there are some downsides to stratified injection but most of them are limited to cold start driveability issues. Well, that and you need a very specialized piston design. regardless, it doesn't actually provide any extra cooling like the guy said (and you corrected). But it kinda has the same effect.
Very cool stuff, but very hard to calibrate haha.
Very cool stuff, but very hard to calibrate haha.
Actually DI is kind of like lowering intake temps. Well intake temps will be the same but since you are not compressing fuel and air in the combustion chamber preignition only occurs if fuel timing is too soon. Or that's the theory anyway.
Tons of potential for tuning with DI. Especially with dual variable cams. Now you don't have to squirt fuel before/during intake valve opening for it to be useful. You could squirt a little near TDC and maybe a little more with the piston on the way down. Or while the exhaust valve is open. Wanna keep your turbo spooled off throttle? Of course just speculating here but most of this thread has been just that.
Tons of potential for tuning with DI. Especially with dual variable cams. Now you don't have to squirt fuel before/during intake valve opening for it to be useful. You could squirt a little near TDC and maybe a little more with the piston on the way down. Or while the exhaust valve is open. Wanna keep your turbo spooled off throttle? Of course just speculating here but most of this thread has been just that.