Air Pump Question
Thread Starter
Racer
Joined: Feb 2003
Posts: 491
Likes: 2
Air Pump Question
What is the function of the air pump? I had an 88 iroc with a tpi motor and it didn't have one but my 85 vette does. Is there any side effect to replacing it w/ an AIR PUMP REPLACEMENT PULLEY KIT?
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Air Pump Question (Ray383)
The AIR pump pumps fresh air to the main cat behind the transmission. That cat is specifically for taking care of HC emissions. By removing the AIR pump, you'll make it harder to pass emissions, as the cat won't have enough fresh oxygen to fully burn the unburnt fuel passing through it.
FWI, the precats are designed for NOx emissions, and the main one is for HC. They are not there for redundancy in the system.
FWI, the precats are designed for NOx emissions, and the main one is for HC. They are not there for redundancy in the system.
Thread Starter
Racer
Joined: Feb 2003
Posts: 491
Likes: 2
Re: Air Pump Question (CorvetteZ51Racer)
thanks for the info. I have a question about your 358 motor. I have a friend who is thinking of getting into bush racing. What is the deal with the 358ci motor size. Where can he find chassis and drivetrain parts
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Air Pump Question (Ray383)
thanks for the info. I have a question about your 358 motor. I have a friend who is thinking of getting into bush racing. What is the deal with the 358ci motor size. Where can he find chassis and drivetrain parts
Basically, the list of internals for most of the Chevy's is
1) Sonny Bryant forged crank (usually 38-42 lbs, depending on setup...the heavier cranks for the open motors, lighter for plate motors)
~$3000
2) Carillo rods
~$1000
3) JE Pistons
~$600
4) SB2.2 heads (best source is Chapman Heads...BIG $$$)
~$5000-$6000
5) Wilson intake manifold
~$700
6) BLP carb
~$1300
7) T&D or Jesel shaft rockers
~$1000
8) titanium valves
~don't remember
9) GM NASCAR Block
~$4000
Basically, once you're all said and done, if he can build it himself for under $25k, he's done well.
Thank God we don't pay full price for parts every time we blow the motors up.....
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Air Pump Question (Ray383)
Do you think the end power output justifies 25k for a 358 motor?
Racer
Joined: Sep 2000
Posts: 337
Likes: 0
Re: Air Pump Question (CorvetteZ51Racer)
Sorry for interrupting in your 358 conversation. ;)
I have a question about the AIR pump removal. My pump is still there but I have new catalytic converters, without the airtubes and the car did pass the emissions last year, so I figure that I don’t need the air pump anymore?
Or does the air pump do anything else for the emission system, like pumping air into the egr or something?
:cheers:
I have a question about the AIR pump removal. My pump is still there but I have new catalytic converters, without the airtubes and the car did pass the emissions last year, so I figure that I don’t need the air pump anymore?
Or does the air pump do anything else for the emission system, like pumping air into the egr or something?
:cheers:
Drifting
Joined: May 2002
Posts: 1,509
Likes: 3
From: Hazel Park MI
Re: Air Pump Question (Cratzy)
I'm not at my resource manuals, but I think I remember reading that the AIR pump only operates when the car is warming up during open loop. I have an 85, which has only one cat. Someone else will chime in I'm sure. :seeya
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Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Air Pump Question (jmrl98)
I'm not at my resource manuals, but I think I remember reading that the AIR pump only operates when the car is warming up during open loop. I have an 85, which has only one cat. Someone else will chime in I'm sure. :seeya
As far as the car without the AIR tubes going to the cats, if you still have the stock manifold or have headers with AIR tube provisions, you are still getting an emissions benefit from the AIR pump, as it's also pumping air into the headers right at the heads.