Exhaust flanges

XJOSHX · 12-13-2008, 01:28 PM

Where can I get 944 exhaust flanges so I can build my own custom headers? If I chopped up the stock manifolds do you think I could salvage the factory stuff, or is there an alternative without machining new ones?

Schumi · 12-13-2008, 06:02 PM

The stock primaries are cast iron, not steel. So if you took an old set and cut off the flanges, welding header tubing to them is possible, but the welds might not turn out the best or the strongest.

ERAU944 · ERAU944's Garage

umm what?

the stock manifolds on pre '85.5 cars were cast iron, but after were tube steel.

to answer the original poster, i suppose you could use the stock flanges (head side), and weld whatever tubing you decide to make onto those. after that you can use whatever flange style you like to finish out the exhaust

Schumi · 12-14-2008, 01:53 AM

Hmmm, did I just find another difference in the 924S from the 944? I believe my primaries on both of my cars are cast. I know for certain they are on at least the track project.

I knew the turbos were tube steel, didn't think the NA's had them..

agent213 · 12-14-2008, 07:11 AM

take off your factory header pipes, bring em to a machine shop and get them to cut you some flanges. some nice water-jet sliced ones would be sweet

ERAU944 · ERAU944's Garage

it's quite possible (and evidently true) that the 924S cars had the cast headers, seeing as how they shared just about everything else engine wise with the early 944. i thought the early 944's had issues with the cast iron manifolds cracking. i replaced the ones in my '84 with tube steel ones, and i think in the process saved around 20lb of weight

Schumi · 12-14-2008, 01:33 PM

Mike- that's right, the cast ones can crack.

It's strange as though the 924S's have the cast headers, the engines are updated and have the late style tensioner and the late style fuel rail. Why the headers weren't changes is strange.

JonA · 12-14-2008, 05:35 PM

My87 924s has the early style tensioner. I think Porsche just used whatever parts they had in the bins!!! Ordering parts is always an adventure......
I'll check tomorrow but I swear mine also has the steel headers. I'll check tomorow.

Jon

drew1 · 12-14-2008, 06:43 PM

Try Stahl Headers. They used to sell flanges.

ERAU944 · ERAU944's Garage

Quote:

Originally Posted by Schumi

Mike- that's right, the cast ones can crack.

It's strange as though the 924S's have the cast headers, the engines are updated and have the late style tensioner and the late style fuel rail. Why the headers weren't changes is strange.

the ones i've seen had the early fuel line routing (by the brake booster, not through the passengers side wheel well)

mixed bag indeed.

Schumi · 12-14-2008, 10:49 PM

Quote:

Originally Posted by ERAU944

the ones i've seen had the early fuel line routing (by the brake booster, not through the passengers side wheel well)

mixed bag indeed.

lol actually they are a mix- yes they have the brake booster side feeding lines but the fuel damper and regulator are on opposing ends of the rail like a late car, not at the same end like an 84.

It would be interesting if there was manufactuing dates on individual parts. 924S's would have parts produced ranging from 1980 to 1988..

Zero10 · 12-14-2008, 11:06 PM

Quote:

Originally Posted by Schumi

Mike- that's right, the cast ones can crack.

It's strange as though the 924S's have the cast headers, the engines are updated and have the late style tensioner and the late style fuel rail. Why the headers weren't changes is strange.

What? I've never seen the cast ones crack, can you back this up?

I've seen 4 different sets of cracked tubular headers but never the cast ones. I thought they ditched them to save the extra weight, not due to cracking issues?

Schumi · 12-15-2008, 12:40 AM

That's probably true about ditching due to weight, but the cast ones can crack if they overheat. This is why you never use header wrap on cast headers- it traps the heat in and causes them to crack.

petrolhead611 · 12-15-2008, 09:08 AM

my '86 924S has tubular steel headers from new.

XJOSHX · 12-15-2008, 01:27 PM

While searching google I found some "exhaust flanges" for 944's but I don't think it is on the head side of things. I just want to make my own turbo headers for a custom set up. I'll search the stahl stuff now.

HondaDustR · 03:44 PM

Quote:

Originally Posted by XJOSHX

While searching google I found some "exhaust flanges" for 944's but I don't think it is on the head side of things. I just want to make my own turbo headers for a custom set up. I'll search the stahl stuff now.

If all you want is the flanges, wouldn't it not even matter what "side" they are from, since the two sides have to match each other in order to bolt up, anyway?

Personally, I think the fuel lines comming up near the brake booster make so much more sense than running them by the exhaust manifolds. I'm glad mine does it that way. And yeah, you practically have to be a 944 build history expert to figure out what parts are from what years on these things. I think technically, the 924S didn't get the steel headers until 88, but maybe some of the late 87's got them, too.

Seems like any header can crack, but I always heard that the steel ones were the ones prone to cracking. I think they were updated a second time to fix the cracking problems, but I'm not sure (the ones with the bellows looking sections in the 1-4 manifolds?).