Sab

is this he same I have on my '82 Euro?

http://cgi.ebay.de/ws/eBayISAPI.dll?...162338698&rd=1

or is this the deysired upgrade for the '82 exhaust?

Vilhuer

AFAIK those are same "not good" cast versions that were used on all 16V engines. Only real factory upgrade is '85-86 32V headers which were not used in same MY ROW cars for some reason. Fact that one side needs shot extension to fit 16V exhaust might be one reason but this doesn't explain it totally IMHO. At that time factory development budget should have allowed change for ROW 16V exhaust too to make them fit.

toofast928

Sab, you can have my cast iron exh manifolds for free! Same thing as the one's in Ebay. No performance upgrade.

PorKen

Those are the same as the US manifolds, with the EGR mount on the 1-4 side. Later euro manifolds don't have the EGR casting and are a bit lighter.





The euros were factory rated at 300HP/263TQ with cast iron manifolds...

Both the euro and US cast manifolds have roughly 51mm (2") ID outlets. The gasket ID is 55mm (2 3/16"). Less than an hour of die grinding, with the manifolds still mounted, to gasket match the opening, gives about as much flow as the 85-86 SS manifolds, IMHO.

The problem is the head pipes. (Usually replaced when putting in the SS manifolds.) The US pipes are necked down to only 1¾", right after the flange. '85 and up have 2" pipes. (Most X-pipes have 2¼", which is too big for 4.5L, I think.) Porting and '86 2" pipes gave me 214/277 RWSAE, +18% = 253/327 crank!

I have 4° cam advance now, so I should have >280 RWTQ!

hacker-pschorr

I don't know Porken, there are multiple 928's making over 600hp with the stock SS manifolds.

You know better than I the flow characteristics of an exahust manifold has more variables than simply the ID of the pipe. What is the ID of each hole going to the head?

If you really want power, go to headers anyway .
My 79 is only 40hp shy of an S4 with only exhaust work (stock cam / ignition timing on 87 octane).
This test was on the same dyno / correction factor.

PorKen

The cast iron manifolds have nice long radii, and steplessly expand as they move away from the exhaust port.

The ID of the SS manifolds may be a bit larger at the flanges, but it's a log. They have internal welds showing, and the accordian makes turbulence, too.

PorKen

My '81 posts nearly the same numbers as your '79, and it has mufflers.

With '79 cams, it will be at least equal, but more likely...superior.