What mods have to be done to cast iron exhaust manifolds?
12-02-2001, 03:10 AM
#1
TECH Resident
Thread Starter
Join Date: Nov 2001
Location: san diego ca
Posts: 854
Likes: 0
Received 0 Likes
on
0 Posts
What mods have to be done to cast iron exhaust manifolds? <img src="images/icons/confused.gif" border="0"> in order to extract maximum smog legal performance, the cast iron manifolds are preferred over the tubulars, yes? What machining needs t be done to optimize the cast pieces (port matching, xtrude honing, removing baffles?)
any ideas?
any ideas?
12-02-2001, 10:44 AM
#2
Re: What mods have to be done to cast iron exhaust manifolds? There have been two schools of thought on this I'm aware of:
00-02 cars have better exhaust flow because the cats and the cast iron exhaust manifolds are better than 98-99 cars
00-02 cars have better exhaust flow because the cats are better but the cast iron exhaust manifolds are actually worse than the tubular steel on the 98-99's.
In either case the 00-02 set up seems to be worth a few more hp.
In any case I think it would be less hassle to have the cast iron ones extrude honed than to hollow log the tubular steel ones. However, the cast iron is fairly thin to keep it light.
One of the board members J Solo (membership number 1135 if you want to look him up and email)has a Black Bird edition T/A that has the cast iron manifolds ported and preped for best flow, maybe he'll see this thread or you could contact him.
[ December 02, 2001: Message edited by: 99 Black Bird T/A ]</p>
00-02 cars have better exhaust flow because the cats and the cast iron exhaust manifolds are better than 98-99 cars
00-02 cars have better exhaust flow because the cats are better but the cast iron exhaust manifolds are actually worse than the tubular steel on the 98-99's.
In either case the 00-02 set up seems to be worth a few more hp.
In any case I think it would be less hassle to have the cast iron ones extrude honed than to hollow log the tubular steel ones. However, the cast iron is fairly thin to keep it light.
One of the board members J Solo (membership number 1135 if you want to look him up and email)has a Black Bird edition T/A that has the cast iron manifolds ported and preped for best flow, maybe he'll see this thread or you could contact him.
[ December 02, 2001: Message edited by: 99 Black Bird T/A ]</p>
