1990 Firebird with 305 TBI V8 octane question
Thread Starter
Senior Member
Joined: Mar 2011
Posts: 710
Likes: 35
1990 Firebird with 305 TBI V8 octane question
I have a 1990 Firebird with the 305 TBI V8 and am wondering what the correct grade of fuel that should be used is.
The owners manual for the car states that the TPI V8 should use 91 octane gasoline,but says 87 octane may be used in the TBI V8 even though it has the exact same 9.3.1 compression.
The owners manual for the car states that the TPI V8 should use 91 octane gasoline,but says 87 octane may be used in the TBI V8 even though it has the exact same 9.3.1 compression.
Supreme Member
Joined: Jul 2005
Posts: 1,675
Likes: 3
From: Arab, Alabama
Car: 1988 Trans Am GTA
Engine: 350 4BBL
Transmission: 700R4
Axle/Gears: 3.27
Re: 1990 Firebird with 305 TBI V8 octane question
The intake on the TBI is so much more restrictive than the TPI that it is unlikely to ping under full load (since it is producing less horsepower). 87 is fine for the TBI.
Thread
Thread Starter
Forum
Replies
Last Post
Pac J
Tech / General Engine
3
May 17, 2020 10:44 AM
