911

Just got the engine out of my hill climber and looking for something to do while the engine is 'done' at API.
Putting the head/manifold gasket on the headers, the difference in diameters is a huge 5 mm. It is realy worth all the effort to grind them to match the gasket diameter?
911

gussy

iTrader: (2)

911,
The answer to that is yes in a turbo you want to have the least restrictions to the exhaust gasses as you said earlier there is a 5mm step from the heads to the manifold I ground my manifolds back to suit the gaskets seemed to improve things but until next time I put the car on a r/road I woulnt know how much of a differance it has made there will have been people who have and will have the r/road results on here.Hope that is of some help.

mark@wrx

API do this to motors that are being repaired as well if you ask.

micared

911, said it yourself really ..... 5mm step between manifold/head. If the manifolds already off, and you've access to the right tools ( air driven die grinder and 13mm tungsten carbide cutter, latter from RS Components ) you're only looking at an hours work! To be fair, think this works best in conjunction with other exhaust based mods, but if it's in bits anyway......

Welloilbeefhooked

iTrader: (3)

911,

Some pics here of before and after

http://www.zen24039.zen.co.uk/Scooby...20WRX/Headers/

911

Thanks for all that guys. I can get the cutter from RS, and the air drill from work, looks like i may as well do it while the engines away.
I was just so surprised to see such a large step. Bit crude !
911

KLR16V

iTrader: (2)

My 93 wrx was the same ported them out to match gaskets , used to get full boost at 3500 rpm now get it at 3000 rpm . Cheap and worth while .

Mark

APIDavid

iTrader: (4)

AND at such reasonable cost.

911

Oh no! Not MORE API extras!
Even I can port these, but on a Porsche they all line up!

That should get APIDavid going (again).........

Such an improvement on spool-up is well worth it.
Hope you have all the gaskets David.

911

StickyMicky

is it possible to use a electric drill to cut the headers?

or maybe a dremmel or sumthing? (no air tools here)

KLR16V

iTrader: (2)

Yes but it will take a lot longer as they do not spin as fast.

Mark

stevey

iTrader: (2)

welloilbefooked thought you werent ment to wrap standard headers

APIDavid

iTrader: (4)

[QUOTE=911 Even I can port these, but on a Porsche they all line up!

That should get APIDavid going (again)......... 911[/QUOTE]

I shan't rise to it, I shan't, I shan't, ......But Porsches cost lots more than Subaru - Dammit! No self control you see !!