Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Ported L98 Iron Heads

Thread Tools
 
Search this Thread
 
Old 10-01-2004, 11:58 PM
  #1  
Member
Thread Starter
 
dj haf's Avatar
 
Join Date: Aug 2003
Location: Miami, Florida
Posts: 420
Likes: 0
Received 0 Likes on 0 Posts
Car: 1990 IROC-Z
Engine: 350 L98
Transmission: 700R4
Ported L98 Iron Heads

i had a friend of mine port my heads for me, and i just had them flow benched. im kinda upset at the results and i'd like to know what to do to make the exhaust flow a little bit more. if anyone has any suggestions, please let me know what you think i should do to get these heads flowing better. valves are 1.94 / 1.5 w/ a 3 angle valve job. i don't want to put a lot of money into these heads so i'd probably end up porting these heads myself. like i said, any suggestions on how to get the exhaust cfm's up would be greatly appriciated i'm just wondering how my intake seems to be flowing better but my exhaust doesn't. thanks in advance

lift intake exhaust
|-------|--------------|-----------
050 30.5 cfm 22.3 cfm
100 62.0 cfm 45.8 cfm
150 95.0 cfm 67.0 cfm
200 126.0 cfm 87.5 cfm
250 154.0 cfm 102.0 cfm
300 173.0 cfm 112.0 cfm
350 190.0 cfm 120.0 cfm
400 204.0 cfm 127.0 cfm
450 208.5 cfm 133.0 cfm
500 207.0 cfm 137.0 cfm
Old 10-02-2004, 12:36 AM
  #2  
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
1083's

That's because those heads are not worth screwing with, regardless what anybody tells you. They are old school technology. Put your time and $$$ into something worth while.
Old 10-02-2004, 12:51 AM
  #3  
Supreme Member

 
Sitting Bull's Avatar
 
Join Date: Jun 2001
Location: Calgary, Alberta, Republic of Western Canada
Posts: 3,238
Likes: 0
Received 4 Likes on 4 Posts
Car: 1986 Sport Coupé
Engine: 305-4v
Transmission: 700R4 and TransGo2
Re: 1083's

Originally posted by Dyno Don
That's because those heads are not worth screwing with, regardless what anybody tells you. They are old school technology. Put your time and $$$ into something worth while.
Not so. You just have to spend some time with them. Without seeing what has already been done I can't offer any advise but you can look over the thread linked at the end of my sig for some help.
Old 10-02-2004, 04:28 AM
  #4  
Supreme Member

 
F-BIRD'88's Avatar
 
Join Date: Sep 2001
Location: Ontario, Canada
Posts: 6,111
Received 52 Likes on 49 Posts
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
Actually the intake side on your heads kinda sucks too.

You should be a right around 225-235 for a home ported head with 160-180 on the exhaust side. (1.94-1.50 valves)

Was the head flowed with a inlet radius plate and exhaust tube during testing? makes a difference.

Like SB said hard to tell ya more without seeing whats done to the ports.

many people had gotten good results with these heads.
Old 10-02-2004, 10:35 AM
  #5  
Member
Thread Starter
 
dj haf's Avatar
 
Join Date: Aug 2003
Location: Miami, Florida
Posts: 420
Likes: 0
Received 0 Likes on 0 Posts
Car: 1990 IROC-Z
Engine: 350 L98
Transmission: 700R4
at the bottom of my flow chart, it says "radius inlet" and some markings i can't understand, and then it also says "open no pipe"...

i think im just going to go out and get some better heads for later down the line in a few months
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
lt500r55
Tech / General Engine
6
09-01-2021 01:30 PM
Vintageracer
Camaros for Sale
12
01-10-2020 05:33 PM
Chuck84TA
Engine/Drivetrain/Suspension Parts for Sale
10
07-15-2016 09:05 PM
beastin91rs
Tech / General Engine
18
10-09-2015 07:38 AM



Quick Reply: Ported L98 Iron Heads



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