gas cap changing performance?
Thread Starter
Supreme Member
iTrader: (2)
Joined: May 2009
Posts: 3,371
Likes: 2
From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
gas cap changing performance?
on a hunch ,i know that our cars use a ccp system (carbon canistor). Ok, well i tried a vented gas cap tonight and noticed that the car acceklerated a little smoother but felt less torquey. I then put back my locking gas cap and immediately felt myself being pushed back in my seat with the torque i am familiar with. Strange. Anyone else exp. this? For the record, when i took off the vented cap i had no pressure release like i do with my regular cap. Maybe that pressure is good.
Thread Starter
Supreme Member
iTrader: (2)
Joined: May 2009
Posts: 3,371
Likes: 2
From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?
No one experiences high pressure when they remove their gas cap? Havent any of you tried a vented cap because of this? any results?
Senior Member
Joined: Oct 2011
Posts: 944
Likes: 0
From: IDAHO
Car: 89 rs
Engine: 2.8 v6
Transmission: M/t
Axle/Gears: 5 Speed Manual
Re: gas cap changing performance?
guess not, i actually never heard of these, how much is the average cost so i can try one? my cap is pretty old and about itme for a new one.
Thread Starter
Supreme Member
iTrader: (2)
Joined: May 2009
Posts: 3,371
Likes: 2
From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?
I bought my locking gas cap at Walmart, its a Stant. I got the factory cap and drilled two small holes in it for testing purposes.
Trending Topics
Supreme Member
iTrader: (3)
Joined: Jun 2009
Posts: 2,350
Likes: 3
From: Mid West
Car: '87 Camaro
Engine: '92 Carb'd 350
Transmission: 700r4
Axle/Gears: factory stock
Re: gas cap changing performance?
Check the gas tank vent. It's on a piece of hose & hangs from the hose.
There is a discussion on it, but I don't recall the thread title, or exact location.
Seems easy to get to IIRC.
There is a discussion on it, but I don't recall the thread title, or exact location.
Seems easy to get to IIRC.
Supreme Member
Joined: Dec 2000
Posts: 1,271
Likes: 1
From: stallings,n.c.
Car: 1989 camaro rs convertable
Engine: 305 tbi
Transmission: 700r4
Axle/Gears: 7.5"3.42 gears forth gen 2000 camar
Re: gas cap changing performance?
doesn't the gas tank vent into the charcoal canaster under the hood?i know its supposed to be under a vacumn to keep the gas fumes from leaking into the air.
Joined: Apr 2005
Posts: 7,736
Likes: 14
From: Not in Kansas anymore
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: gas cap changing performance?
Are purged to the engine under programmed conditions
If line to canister is blocked or system not being purged then common to get pressure build up in tank as noted
Thread Starter
Supreme Member
iTrader: (2)
Joined: May 2009
Posts: 3,371
Likes: 2
From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?
yes,but someone else told me its normal to get pressure
Thread Starter
Supreme Member
iTrader: (2)
Joined: May 2009
Posts: 3,371
Likes: 2
From: Delaware
Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?
i was curious on how a vented cap would change performance and i did feel a difference. yes, i had no pressure when i went to remove gas cap,but car performed differently,just didnt feel as powerful
Member
iTrader: (2)
Joined: Jun 2010
Posts: 482
Likes: 3
From: SE Houston TX
Car: 1986 Iroc-Z
Engine: 355
Transmission: 700R4
Re: gas cap changing performance?
Try an actual vented cap, not a reg cap with holes in it.
I'm about to order mine from mdm it's like 10 bux
My pressure is gone in the tank after I fixed my tank pressure valve
I'm about to order mine from mdm it's like 10 bux
My pressure is gone in the tank after I fixed my tank pressure valve
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
May 10, 2023 07:19 PM






