Exhaust Post your questions and suggestions about stock or aftermarket exhaust setups. Third Gen exhaust sound files and videos!

Headers for 89 305 TPI

Thread Tools
 
Search this Thread
 
Old 01-29-2015, 06:07 PM
  #1  
Junior Member

Thread Starter
iTrader: (2)
 
19875speed's Avatar
 
Join Date: Apr 2012
Location: Pennsylvania
Posts: 64
Likes: 0
Received 1 Like on 1 Post
Car: 1989 Formula Firebird
Engine: 305 TPI
Transmission: 5-speed
Axle/Gears: 3:45
Headers for 89 305 TPI

I have an 89 formula G92 TPI 5-speed and want to put headers on. Not sure what kind I'm going to get. But I need to know will the stock Y-pipe work and what all parts will I need to have them installed? thanks
Old 01-30-2015, 05:54 PM
  #2  
Senior Member
iTrader: (1)
 
greenyone's Avatar
 
Join Date: May 2014
Location: Pittsburgh
Posts: 550
Likes: 0
Received 5 Likes on 5 Posts
Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Re: Headers for 89 305 TPI

Stock Y pipe won't work with any headers that I know of. If you want to stay with the G92 dual cats, I think Dyno Don's makes a set of headers and dual cat Y pipe to match. Otherwise just choose a header that fits a thirdgen and have a exhaust shop fab up a new custom Y pipe or modify your stock one.
Old 01-30-2015, 06:05 PM
  #3  
Supreme Member

iTrader: (11)
 
DynoDave43's Avatar
 
Join Date: Aug 2013
Location: MICHIGAN
Posts: 4,643
Received 754 Likes on 580 Posts
Car: 1988 Trans Am
Engine: L03
Transmission: 700R4
Axle/Gears: 10 Bolt 2.73 Open
Re: Headers for 89 305 TPI

Originally Posted by greenyone
Stock Y pipe won't work with any headers that I know of.
Wow....I did not know that. I thought the whole point of shorties was that they terminated in the same location as the stock manifolds. Learn something new every day here.
Old 01-30-2015, 08:15 PM
  #4  
Member
 
sheikss's Avatar
 
Join Date: Jun 2012
Location: GA
Posts: 216
Likes: 0
Received 1 Like on 1 Post
Car: 88 Trans Am GTA
Engine: 350
Transmission: 700R4
Axle/Gears: 12 bolt 3.73
Re: Headers for 89 305 TPI

If you have to keep the cats then go with dyno don headers, if not go longtubes. Hooker longtubes can be labor intensive so be prepared. I notched and boxed my k member on both sides just to get plenty of clearance with the hookers.
Old 01-31-2015, 08:39 AM
  #5  
Senior Member
iTrader: (1)
 
greenyone's Avatar
 
Join Date: May 2014
Location: Pittsburgh
Posts: 550
Likes: 0
Received 5 Likes on 5 Posts
Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Re: Headers for 89 305 TPI

Or just scrap the dual cats and go with the hooker or heddman shorties and Y pipes. A lot cheaper than Dyno Dons stuff. I'm not sure if those dual cats really have a ton of benefit with the 305 anyway.
Old 01-31-2015, 11:14 AM
  #6  
Supreme Member

iTrader: (1)
 
sofakingdom's Avatar
 
Join Date: Sep 2005
Posts: 26,118
Received 1,688 Likes on 1,283 Posts
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: Headers for 89 305 TPI

Stock Y pipe won't work with any headers that I know of.
Same here.

I thought the whole point of shorties
Nope... it's mostly just so that they'll support a Y-pipe at all. Headers generally come with their own Y-pipe that then bolts to the factory single cat.

If possible, lose the factory dual-cat setup. (you don't say what state you're in so no way to know whether that's an option) It doesn't make as much power as a non-factory single cat, non-factory Y-pipe, and non-factory cat-back. Might make more than a factory single-cat setup but still less than a decent aftermarket one. All it does is make it near about impossible to get any headers at all.

I STRONGLY urge you to get the BEST headers you can; not just the cheeeeeeepest thing you can find that somebody won't go to jail for fraud if they print "headers" on the box; and have them ceramic-coated. Dyno Don's would be a good choice.
Old 01-31-2015, 11:43 AM
  #7  
Supreme Member

iTrader: (8)
 
TTOP350's Avatar
 
Join Date: Oct 2001
Location: Il
Posts: 11,723
Received 773 Likes on 520 Posts
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Headers for 89 305 TPI

bolt on Shorty headers are a mustang world thing. They have shorties that will bolt right to the factory H pipe and H pipes that bolt to stock headers .

Dyno Don headers are about the best, esp if you want to keep the factory dual cat setup and want something that's very close to a true bolt on.
I just ran across the article last night about the dual cat vs the single cat written in 88-9 when the dual cats came out. The dual cat system flows 275 cfm per cat while the single cat flows 250 cfm. This is cold flow through the cats without the factory piping.

Long tubes are a not needed hassle until you hit or want to go past a certain hp level. 500 or so IIRC
Old 01-31-2015, 11:52 AM
  #8  
Supreme Member

iTrader: (11)
 
DynoDave43's Avatar
 
Join Date: Aug 2013
Location: MICHIGAN
Posts: 4,643
Received 754 Likes on 580 Posts
Car: 1988 Trans Am
Engine: L03
Transmission: 700R4
Axle/Gears: 10 Bolt 2.73 Open
Re: Headers for 89 305 TPI

Originally Posted by TTOP350
bolt on Shorty headers are a mustang world thing. They have shorties that will bolt right to the factory H pipe and H pipes that bolt to stock headers .
Perhaps that's what left me with that impression. I also have a set for my Vortec Suburban that were designed (by a company that is no longer in business...Mesa) to work with the factory Y-pipe.
Old 01-31-2015, 11:53 AM
  #9  
Supreme Member

iTrader: (4)
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: St. Cloud, MN
Posts: 4,780
Received 9 Likes on 8 Posts
Car: 1984 Trans Am
Engine: LS1383 in work
Transmission: Magnum F
Axle/Gears: Zexel Torsen 3.73, 28-spline mosers
Re: Headers for 89 305 TPI

Originally Posted by sofakingdom

I STRONGLY urge you to get the BEST headers you can; not just the cheeeeeeepest thing you can find that somebody won't go to jail for fraud if they print "headers" on the box; and have them ceramic-coated. Dyno Don's would be a good choice.

I'm with Sofa on this one. You'll regret buying cheap headers about year after you get them.

I also highly recommend getting the ceramic or jet-hot coated headers.

If you want a great long tube set up, look under the exhaust section, there is a whole sticky thread about "True Dual Exhaust Setups" with pictures.

If you want shorties and don't need Emissions, go with Dyno Don's. If you want shorties but need emission, or if you need emissions period, you want Dyno Don or Hooker 2055 shorty, emissions legal headers.


FYI, the Single 3" exhaust only flows about 5-10cfm less than a true dual 2.5" set up and costs about half as much to buy and install. Also, you won't see any noticeable HP issues with the single 3" until you're over 400hp, possibly closer to 500 as mentioned.

Also, to keep Sofa from having a stroke, please go under "UserCP", then "Edit details" to put your vehicle information in there (After being here and reading his posts for nearly 10 years, It's one of his pet peeves lol).
Old 01-31-2015, 11:59 AM
  #10  
Supreme Member

iTrader: (7)
 
Dyno Don's Avatar
 
Join Date: Mar 2000
Location: Orange, CA
Posts: 5,674
Likes: 0
Received 106 Likes on 65 Posts
Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Re: Headers for 89 305 TPI

My setup...
Attached Thumbnails Headers for 89 305 TPI-dcp_1310.jpg  
Old 01-31-2015, 12:23 PM
  #11  
Supreme Member

iTrader: (4)
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: St. Cloud, MN
Posts: 4,780
Received 9 Likes on 8 Posts
Car: 1984 Trans Am
Engine: LS1383 in work
Transmission: Magnum F
Axle/Gears: Zexel Torsen 3.73, 28-spline mosers
Re: Headers for 89 305 TPI

Originally Posted by Dyno Don
My setup...
That...is sexy!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Orr89RocZ
Power Adders
206
04-25-2016 08:28 AM
armybyrd
Electronics
9
12-05-2015 09:22 AM
st.evel07
Engine Swap
5
08-13-2015 06:15 PM
Sanjay
Engine/Drivetrain/Suspension Parts for Sale
1
08-12-2015 03:41 PM
drathaar907
TPI
0
08-06-2015 04:20 PM



Quick Reply: Headers for 89 305 TPI



All times are GMT -5. The time now is 04:24 PM.