Bigger Headers/ORY Setup Gains? (Boost the same)
#1
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So I upgraded my exhaust this winter and re-pullied the blower back to ~8-9psi. The car previously made 598whp/554wtq on 8.5lbs (16* of timing w/ 11.2 AFR @WOT) with the old exhaust setup. How much do you think I will gain with the larger exhaust given all other things the same? (boost/timing/etc)
Old: 1-3/4 BBK LT's with 2.5" catted Y, cutout (open) and base SS muffler
New: 1-7/8 Speed Eng. LT's with 3" ORY, dynomax 3" intermediate/over axel pipe and Factory SLP CME muffler.
Rest of the setup:
SBE LS1
D1sc (8-9psi) w/ FMIC setup
Ported 243 Heads
PAC 1218 springs
TSP 228R 112
FAST 102 intake/ NW 92 TB
60# injectors / Holley EFI hi-flow rails
FLT 4l65e w/ Yank SS3600
Stock 10 bolt (3.23 gears)
Old: 1-3/4 BBK LT's with 2.5" catted Y, cutout (open) and base SS muffler
New: 1-7/8 Speed Eng. LT's with 3" ORY, dynomax 3" intermediate/over axel pipe and Factory SLP CME muffler.
Rest of the setup:
SBE LS1
D1sc (8-9psi) w/ FMIC setup
Ported 243 Heads
PAC 1218 springs
TSP 228R 112
FAST 102 intake/ NW 92 TB
60# injectors / Holley EFI hi-flow rails
FLT 4l65e w/ Yank SS3600
Stock 10 bolt (3.23 gears)
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#2
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So no cutout with the new setup correct? Even if so, you should pick up a good bit from the y-pipe change for sure. As to how much, that's really hard to say. Depends on how much the current setup is restricting it
#3
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Also, the car is SD tune on 93 and water/meth.