Suggestions to complement my Supercharger upgrade

[3000gttom]

well then, cam gears would be the first thing i would do to take out the overlap in the cams, because with the n/a cams you are going to be blowing unburned fuel and oxygen out the exhaust, this will net you more power and mileage

then downpipe to get more power

next would be a good tuning setup like a 99 ecu clone or aem, and have your own wideband

if you want mileage and reliability then you may want to fabricate a supercharger bypass to keep it from constant boosting

[Blown3000]

well then, cam gears would be the first thing i would do to take out the overlap in the cams, because with the n/a cams you are going to be blowing unburned fuel and oxygen out the exhaust, this will net you more power and mileage

then downpipe to get more power

next would be a good tuning setup like a 99 ecu clone or aem, and have your own wideband

if you want mileage and reliability then you may want to fabricate a supercharger bypass to keep it from constant boosting

Cam gears? I guess that you lost me! Maybe a little detail to help me understand. My boost gauge doesn't show that I'm constantly under boost so I'm not understanding. I do have a wideband O2 installed.

[3000gttom]

with stock cams there is a period of time that both the intake and exhaust valves are open, with the supercharger you are blowing air and fuel into the intake valve and then they go out the exhaust valve that is still open, you use adjustable cam gears to take the overlap period out, this will result in more effective boost and you may have boost at low rpms once you do this so a bypass may then be useful

[Blown3000]

with stock cams there is a period of time that both the intake and exhaust valves are open, with the supercharger you are blowing air and fuel into the intake valve and then they go out the exhaust valve that is still open, you use adjustable cam gears to take the overlap period out, this will result in more effective boost and you may have boost at low rpms once you do this so a bypass may then be useful

Okay I see. That makes sense if injectors are spraying during that entire period the intake valves are open but I read that the injectors do not spray the entire duration, especially below the higher rpms. In carburetored motors I totally see your point.

You used the term "may have boost" are you speaking in theoretical terms?

[3000gttom]

on the boost thing, right now there is probably enough time that both valves are open that you dont read any boost because enough air has been blown out the other side of the engine. if you use cam gears to remove the overlap with a positive displacement supercharger like yours then you will probably have boost through the entire rpm range and therefore would need to add fuel at low rpms because your boosting


edit: if anyone knows for sure about when the injectors fire i'd like to know for sure

[ibsorgn]

In the 6g72 the fuel is sprayed when the intake valve is open. The amount of fuel injected is calculated as a pulsewidth which is defined in milliseconds. The higher the rpm and load, among other variables, the longer the pulsewidth (more fuel is injected). Modern day injectors are engineered to atomize the fuel when open.
When a bypass valve is used, when open, will equalize the vacuum pressure throughout the entire system eliminating nearly all the parasitic loss. According to Magnuson their MP90 will use less than 1/2 a hp to spin the supercharger. See Magnuson web site for complete specs.

[3000gttom]

thx for clarification,

still in stock form the overlap in the cam timing allows fuel and air to be pushed out the exhaust

[ibsorgn]

thx for clarification,

still in stock form the overlap in the cam timing allows fuel and air to be pushed out the exhaust

Air for sure, probably some Fuel at higher rpms due to longer pulsewidth. ECU Fuel maps will richen AFs when operating in high throttle mode.

Blown3000: Keep your eye on that wideband gauge when running under boost for any indications of lean operation especially if you mod that exhaust as your propably nearing your AF tiping point.

[Blown3000]

Have chosen to go with Long tube headers and a low restriction exhaust. Should have everything installed over this weekend. In keeping with my desire not to make internal modifications I chose not to go the cam gear route. Should the motor go lean with these mods can you suggest cures? I know that eventually the real fix is an injector upgrade as will as an ECU and/or a piggyback controller. Just trying to be proactive.

[3000gttom]

just be sure to log everything and be especially careful in the mid rpm's because the stock fuel map is kinda lean there for boost...but seriously a proper tuning setup is necessary on a supercharger build if you plan on keeping this car on the road