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Header Installation

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Old Feb 4, 2026 | 09:23 PM
  #1  
matt6simmo's Avatar
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From: Sicklerville, NJ
Car: 88 Trans Am
Engine: 305 TBI
Transmission: 700r4
Header Installation

So I am attempting to do my first ever header install on my 88 firebird with the 305 tbi. I am currently halfway through taking the manifolds off (just fighting the last three bolts on the passenger side with ac). I wanted to ask this before I got to the stage. I was wondering how important the three support braces that go to the ac, alternator, or power steering pump are that would normally go on a manifold stud. What did you guys do to either reuse the brackets or discard them or what? The headers are hooker 2460s I got for 40 bucks so i figured Id give it a go while the car is undrivable in this weather anyway. Any other header installation tips or trick would be much appreciated as well. Also if you have an aftermarket dipstick recommendation it is looking like the bracket that goes to the manifold is going to have to be cut.
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Old Feb 15, 2026 | 12:35 PM
  #2  
dixiebandit69's Avatar
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From: The ******* of Texas
Car: '89 Firebird Formula
Engine: TBI 305
Transmission: T5
Axle/Gears: 10-bolt, 3.42s, Torsen diff.
Re: Header Installation

Originally Posted by matt6simmo
So I am attempting to do my first ever header install on my 88 firebird with the 305 tbi. I am currently halfway through taking the manifolds off (just fighting the last three bolts on the passenger side with ac). I wanted to ask this before I got to the stage. I was wondering how important the three support braces that go to the ac, alternator, or power steering pump are that would normally go on a manifold stud. What did you guys do to either reuse the brackets or discard them or what? The headers are hooker 2460s I got for 40 bucks so i figured Id give it a go while the car is undrivable in this weather anyway. Any other header installation tips or trick would be much appreciated as well. Also if you have an aftermarket dipstick recommendation it is looking like the bracket that goes to the manifold is going to have to be cut.
I made some spacers out of steel tubing to mount the factory support brackets on my headers.
I made a small bracket out of sheet metal to mount my dipstick tube.
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Old Feb 15, 2026 | 02:42 PM
  #3  
Tom 400 CFI's Avatar
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From: Park City, UT
Car: '92 Corvette, '89 1/2-a-'Vette
Engine: LT1, L400
Transmission: ZF6, T5
Axle/Gears: 3.45, 3.31
Re: Header Installation

^That^.

I would say that those brackets are pretty important. Might work w/o them....but it also might throw belts too, if the accessories are shaking around, fore and aft. And that'd suck.
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Old Feb 18, 2026 | 11:24 AM
  #4  
Don Fetherolf's Avatar
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From: Eastern PA
Car: 1989 Pontiac Firebird Formula 350
Engine: 5.7 TPI
Transmission: Auto
Axle/Gears: 9 Bolt 3:27
Re: Header Installation

Originally Posted by matt6simmo
So I am attempting to do my first ever header install on my 88 firebird with the 305 tbi. I am currently halfway through taking the manifolds off (just fighting the last three bolts on the passenger side with ac). I wanted to ask this before I got to the stage. I was wondering how important the three support braces that go to the ac, alternator, or power steering pump are that would normally go on a manifold stud. What did you guys do to either reuse the brackets or discard them or what? The headers are hooker 2460s I got for 40 bucks so i figured Id give it a go while the car is undrivable in this weather anyway. Any other header installation tips or trick would be much appreciated as well. Also if you have an aftermarket dipstick recommendation it is looking like the bracket that goes to the manifold is going to have to be cut.
Early last year I installed Hedman headers on my 1989 Formula 350. Yes the last 3 manifold bolts on passenger side are p i t a with ac! Especially when the very back one breaks off and ended up pulling the head to remove the broken bolt. Found out that Sbc heads have 2 bolt holes about a half inch apart at the end of the head. Depends on what manifold are needed for the application it’s in and my headers used the other hole without the broken bolt. Chalked it up as a learning experience!
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Old Feb 18, 2026 | 04:47 PM
  #5  
matt6simmo's Avatar
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From: Sicklerville, NJ
Car: 88 Trans Am
Engine: 305 TBI
Transmission: 700r4
Re: Header Installation

Originally Posted by Don Fetherolf
Early last year I installed Hedman headers on my 1989 Formula 350. Yes the last 3 manifold bolts on passenger side are p i t a with ac! Especially when the very back one breaks off and ended up pulling the head to remove the broken bolt. Found out that Sbc heads have 2 bolt holes about a half inch apart at the end of the head. Depends on what manifold are needed for the application it’s in and my headers used the other hole without the broken bolt. Chalked it up as a learning experience!
That is really promising to hear. I am currently on the last 2 (mainly the second to last). Im going to try a pass through socket and rachet set to see if i can get it out. It is really close to rounding and i would prefer not to pull the head or try and weld a new nut on the end of the stud.
Thank you all for reaching out. If i remember i will write up my experience once i get the headers on and the engine running. I have seen some posts about extensions for the brackets so hopefully i can find some specifics on the spacer sizes.
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Old Feb 18, 2026 | 10:38 PM
  #6  
Tom 400 CFI's Avatar
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From: Park City, UT
Car: '92 Corvette, '89 1/2-a-'Vette
Engine: LT1, L400
Transmission: ZF6, T5
Axle/Gears: 3.45, 3.31
Re: Header Installation

Originally Posted by matt6simmo
Im going to try a pass through socket and rachet set to see if i can get it out. It is really close to rounding and i would prefer not to pull the head or try and weld a new nut on the end of the stud.
Heat the head around the stuck manifold bolt. Not a little....a LOT. Heat the wee out of it, then back the bolt right on out of there.
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Old Feb 19, 2026 | 09:42 PM
  #7  
Ballancers's Avatar
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From: Wilmington, NC
Car: Pontiac Firebird 91’
Engine: 305 TBI
Re: Header Installation

Originally Posted by dixiebandit69
I made some spacers out of steel tubing to mount the factory support brackets on my headers.
I made a small bracket out of sheet metal to mount my dipstick tube.
I just completed my Hedman header project on the same set up, and I ordered a stud kit on Amazon that had the same thread pitch but it allowed me to thread in the nut that retains the accessory brackets. I did need to alter the some of the screws a tad to install the nut and bracket properly, but it ultimately worked for me!

if you decide to order these - just confirm your thread type (should all be the same for sbc)


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