snowy78

Sorry for my lack of knowledge here guys but what is this and what does it do ?

WRXshaneWRX

iTrader: (1)

ported = better/more flow which can help spool times

wrapped = lower nderbonnet temps and to a very small degree better exhaust flow

The Hoff

iTrader: (5)

Headers is another word for your exhaust manifold.

From the factory they are cast iron and they dont match up very well with the outlet ports from the engine. The results in the gas flow being resticted due to turbulance.

Porting is when you cut away the metal from the exhaust manifold to match up better with the outlet ports from the engine. The smoother the tranisiton between engine and headers means a faster flow and this inturn can increase power (faster spool of turbo and less restriction at high flows). The porting can also be done from the headers to the up-pipe which is the pipe that goes between the headers and the bottom of the turbo.

Take a look at this for pictures..... P+P Exhaust Manifold

Wrapping the headers and up-pipe in insulating material helps hold in the heat which stops it getting into you engine bay and sucked into your air inlet. Hot air holds has less oxygen (less dense) than cold air, and the more oxygen you can get into the engine per piston stroke the bigger the bang = more power!

dynamix

iTrader: (3)

https://www.scoobynet.com/scoobynet-...t-headers.html

snowy78

Excellent Thanks for all your help, I now understand !!

ClintUK

The Hoff's spot on, but added to his comments, wrapping not only helps keep under bonnet temps down, but also keeps exhaust hotter and hot gas flows quicker too as the pressure is higher, an added benefit for flow.

snowy78

Can the wrapping be done while eveything is still connected or do you have to take it all of and slide the pipes through like a sock ?

T5OLF

iTrader: (4)

You need to take the headers off and cut off the lugs for heat shield, I used a grinder with a cutting disc. You then need to wrap them like you would a set of push bike racing handle bars. Soak the heat wrap first but don't make it soggy just damp.

ClintUK

No. Every thing has to come off. The old tin heatsheild may require grinding off but nuts and bolts should come out with a bit of effort.

I actually ground off the mounting points for the original heatsheild at they make wrapping a pain.

more photos....

sponners

iTrader: (4)

you can do yourself or have them done for you


https://www.scoobynet.com/private-sa...e-service.html

snowy78

Thanks all

minty

iTrader: (1)

do you have any new headers to fit or are you looking at doing the factory fit ones ?

snowy78

By saying factory fit ones you mean the ones currently on the car ? If so yes I was thinking about doing these but dont know if ive got the energy to take the ca apart at the mo !!!

silent running

They're actually really easy to remove as long as nothing's seized. Jack front of car, unbolt headers from up-pipe first (two bolts), then three bolts on each side of the headers and that's it, seriously there's nothing else to it. Probably the easiest exhaust manifold in the world to remove! A 1 spanner in the Haynes.

snowy78

Might give it a go then, thanks silent, what is the wrapping called and wheres the best place to buy it ?

As for the porting ? how is this done ?

silent running

Porting on the headers can be a bit of a chore. TBH you'd be better to send them off to Harvey Smith for porting. The headers are cast iron and you're more likely to blunt all your cutting tools than achieve anything unless you've got an air powered die grinder. It's not like porting aluminium which is fairly straightforward and can be done with a drill and rotary burrs, or even a flapwheel.

The heat wrapping is much more suitable for the amateur. I have always used DEI or Thermotec wrap; a 1" wide x 50' long roll was just enough for my headers with a little left over. You can get much cheaper wrap than that: some say it's OK, others say it disintegrates after a while. You'll also need some lockwire or stainless steel ties to hold the wrap in place. You can basically get everything you need off ebay.

snowy78

Great stuff silent thanks mate

silent running

No problem. You may find it better value for money in terms of cost and time if you just get someone like Harvey to do the whole job. Wrapping a set of stadard headers also involves grinding off the heatshields and the lugs. TBH it's a complete pain in the **** if you don't already have all the equipment. In fact you could get the whole set of his ported headers and special up-pipe to suit, wrapped and ready to bolt on, all on exchange for your own standard headers.

snowy78

Thanks again but the only problem with doing it that way would be being without a car for ? as long as the snail mail takes to deliver mine to hime and then his to mine ?

Mocom Racing

iTrader: (2)

We have OE Subaru manifolds ported and wrapped on the shelf ready to go, £160 including next day delivery and VAT on an exchange basis.
Should you need them as a matter of urgency we would initially charge £250 for our ported manifold and refund you £90.00 on receipt of your originals.