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phils89sc
10-22-2010, 02:22 AM
I know I will probably get owned on this question, but it begs for an answer.

I know that as you open up your exhaust with more freely flowing items, boost will drop right? The mods to my car are true dual 2.25" to two high flow cats, then to a Flowmaster dual in /our muffler /resonator. From the, we continue all the way with 2.25" dual with no mufflers to the exit at the rear bumper. So it flows pretty good, not as good as some, but good enough for now.

My boost levels prior to my HG change put per about 9 psi. Now during the HG overhaul were about 9.5 to ten. During my HG swap, I ported the exhaust manifolds because I had them out. Now that she is running again, my boost levels seem to be at around 8.5 or so. Could this be contributed to my porting the exhaust manifolds put? She also has a cold air intake kit as well. I have checked all over for boost / vacuum leaks, Zip tied most hose connections around the SC, etc. So, am I at the point where an overdrive jackstaff or SC pulley are in order to bring my boost levels back up?

Btw, many thanks to all for helping me with my idle issue. I ended up pulling the throttle body getting the throttle plate screw adjusted to one turn past contact with the throttle stop. I slotted my TPS holes to allow for tweaking and adjusted the idle voltage at the TPS via the TPS adjustment to .95 volts. Once that was done I reassembled and fired her up. She now idles near perfect. Thanks for everyones help.

Phils89sc

fturner
10-22-2010, 10:38 AM
I know I will probably get owned on this question, but it begs for an answer.

I know that as you open up your exhaust with more freely flowing items, boost will drop right? The mods to my car are true dual 2.25" to two high flow cats, then to a Flowmaster dual in /our muffler /resonator. From the, we continue all the way with 2.25" dual with no mufflers to the exit at the rear bumper. So it flows pretty good, not as good as some, but good enough for now.

My boost levels prior to my HG change put per about 9 psi. Now during the HG overhaul were about 9.5 to ten. During my HG swap, I ported the exhaust manifolds because I had them out. Now that she is running again, my boost levels seem to be at around 8.5 or so. Could this be contributed to my porting the exhaust manifolds put? She also has a cold air intake kit as well. I have checked all over for boost / vacuum leaks, Zip tied most hose connections around the SC, etc. So, am I at the point where an overdrive jackstaff or SC pulley are in order to bring my boost levels back up?

Btw, many thanks to all for helping me with my idle issue. I ended up pulling the throttle body getting the throttle plate screw adjusted to one turn past contact with the throttle stop. I slotted my TPS holes to allow for tweaking and adjusted the idle voltage at the TPS via the TPS adjustment to .95 volts. Once that was done I reassembled and fired her up. She now idles near perfect. Thanks for everyones help.

Phils89sc

In regards to your TPS adjustment, going to .95 volts didn't change anything at all.. it was adjusting the stop screw and allowing a bit more air in is what sorted it out, which obviously means you've taken back to where it should be on a stock setup.

The TPS works on the bases of the EEC grabbing the voltage reading at key on, and that is then considered the "closed" throttle position until you turn the key off. The range for that is about .75 to 1.10 volts or so... outside of that range and the EEC will turn the CEL on and report a TPS failure.

Fraser