Guy's

I do know Cast Iron manifold advantage is on its strength. But i would like to know this. Is it very tough or difficult to unweld flange from cast iron manifold?

Unweld a flange from a cast iron manifold? Are you kidding me?

you cant weld on cast iron. if ur trying to add on a tap for a sensor, ur gonna have to bore a hold and thread it, then add a tap that way. but anyways, no, you cannot unweld anything on a cast iron.

This post has been edited by CaliJeff: Dec 14, 2007 - 1:07 PM

Although it is not easy and not recommended, you "can" weld on cast iron.
You don't unweld anything. You just cut it off.
Cast iron manifold is cheaper when produced in high volume.
It is usually more durable than tube manifold but it does crack if it's not designed well.
A well built tube manifold will work just fine and is much easier to deal with.

This post has been edited by Gary: Dec 14, 2007 - 1:41 PM

The best bet to keep the stock cast manifold is to use an adapter flange added to the end of the manifold. Don't modify the stock manifold (other than maybe to port or polish it).

-Charlie

PS. When I added an EGT probe to my exhaust manifold, I drilled it, tapped it and threadded the fitting in, then welded around it to make sure it would stay and not leak. So you can weld cast iron to steel or stainless, but it won't have the strength of a normal steel to steel weld.

not to hijack the thread ne one know where to get a new cast iron manifold?

HAHAHAHAHAHA. That was priceless.

>
What was priceless?

Turbonetics make an aftermarket T3 cast manifold.
The wastegate placement is kinda weird though (on a runner).

>

Yes you can weld cast iron... Just use a nickel rod Preferably preheat the cast iron manifold up to temperature, weld it, and then wrap a heat blanket on top to slowly cool it off.

Lots of factory OEM parts, such as engine brackets, manifold supports, etc.. are sometimes two cast iron pieces welded together.