[wang970305]

I have a GPI ported LT2 IM, however, the snout was not fully ported to 95mm. If I get a local shop port the snout to true 95mm, will it give me more power? Also, would I need to a retune?

[vince3]

2. Port-Matching to the 95mm Throttle Body
• Description: Enlarging and shaping the LT2’s inlet to match the 95mm throttle body’s bore (ensuring a smooth transition, no step or mismatch) minimizes airflow disruption at the TB-intake interface.
• Power Gain:
• Without Port-Matching: The 95mm TB’s full potential is slightly restricted by the LT2’s smaller inlet (stock LT2 inlet is ~87-90mm).
• With Port-Matching: Adds 3-7 RWHP, 2-5 lb-ft over unported LT2 + 95mm TB. Gains focus on high-RPM (5,500-6,500 RPM), as the smoother transition maximizes TB flow.
• Dyno Evidence: LS1Tech and Texas Speed note 3-8 RWHP from port-matching on LT intakes, with smaller gains (3-5 RWHP) on already-ported setups (2020 posts).

Grok says 3-7hp in a typical FBO car. I was going to get my MSD ported in Houston and the only local person I would trust would be Greg Good.

[wang970305]

Originally Posted by vince3

2. Port-Matching to the 95mm Throttle Body
• Description: Enlarging and shaping the LT2’s inlet to match the 95mm throttle body’s bore (ensuring a smooth transition, no step or mismatch) minimizes airflow disruption at the TB-intake interface.
• Power Gain:
• Without Port-Matching: The 95mm TB’s full potential is slightly restricted by the LT2’s smaller inlet (stock LT2 inlet is ~87-90mm).
• With Port-Matching: Adds 3-7 RWHP, 2-5 lb-ft over unported LT2 + 95mm TB. Gains focus on high-RPM (5,500-6,500 RPM), as the smoother transition maximizes TB flow.
• Dyno Evidence: LS1Tech and Texas Speed note 3-8 RWHP from port-matching on LT intakes, with smaller gains (3-5 RWHP) on already-ported setups (2020 posts).

Grok says 3-7hp in a typical FBO car. I was going to get my MSD ported in Houston and the only local person I would trust would be Greg Good.

Man, thanks for your input! Where does Grey work at?

[wang970305]

Also, I have a FBO ECM tune already, if I ported out the IM snout, would I need a retune?

[vince3]

Grok says it would most likely need to be tuned to see the gains. Without tuning, it would run slightly lean from what it says. Who did the tune? Who did you get to install your headers? I've found one shop in the houston area that is reasonable (Ace Performance Exhaust) but I'm concerned about getting it installed without leaks.