ALFAGTV6.COM

[Mats]

I agree w/ Fedezyl, but the bends occur pretty far out from the head so laminar flow loss is lessened compared to being right near the head. even some of the best designed expansion pipes have even greater than 90dg bends before major expansion takes place.

I like to wrap my hedders keeps everythin in the engine bay cooler and some say may increase exhaust flow at pipe wall interface...

Some may disagree, but new pipes not worth it unless you are looking for every bit of power.

If that is the case, Here something to make you feel better...

It's a bit difficult to see but I think he means that the primarys are 90 degree to the face of the head rather then the ~45* angle you need to have a smooth transition between the port and the exhaust system. Looks like it was made for a 105 car as well with that collector, where is the steering rack?

Laminar flow in the exhaust? That is impossible, clearly turbulent. Maybe you mean detached flow?
Wrapping headers is up to your personal taste I guess, I would never-ever do it unless I had a serious heat problem that couldn't be solved in any other way.

[MD]

Under no circumstance wrap cast iron manifolds. The insulation works but it causes the maifold to crack-just ask me how mine developed a Grand Canyon crack.

There are two ways to insulate mild steel pipe.

1 Place a "blanket" around the manifold.

2 Directly wrap each pipe (not recommended for manifold)

Using an insulation blanket arrangement for the mild steel pipes eg headers, (other than cast iron) is ok and keeps radiant heat from affecting things like brake fluid temp and engine mount rubbers etc.

Wrapping the balance of the pipes keeps cabin temps down which can be very important in hot climates.

[x-rad]

Yep MD, don't ever wrap cast Fe. Even welding it is a pain in the ass

I wraped stainless and steel headers before, no problems ever, but they were 'well' made by me and an exhaust guy. In fact, my whole turbo (exhaust side) was wrapped down to the lower pipe..

MAts: yes you are right of course, if you are talking about the more central flow patters within each exhaust pulse closer to the head. Towards and against the heated exhaust wall, the hot air is moving more slowly comparatively speaking, while the whole mess is moving to lower pressure. tube diameter, constant radius bends are attempst to keep up on velocity and outflow volume in (what I should have said) an attempt at more laminar flow patterns.

[Barry]

How did I miss all this ??

[Amit_Alfaman]

Guess what???

I bought another Giulietta....

Its a monster!!! A 1985 2L Exec. I have never felt power like this before.

[ALFA GTV6 GP]

He's joking right

[Amit_Alfaman]

I really wish i could own a Gtv6

[fedezyl]

I really wish i could own a Gtv6

Or do like me and put a V6 in it....

[Giuliettaevo2]

Here are some pics of my old Giulietta. It was painted flat black and had a TS engine and drivetrain. The brown widened Giulietta is also mine, long standing project, full metal wide body. the last picture shows the floor of a very rusty Giulietta that is now being used under a 33.

The other pictures are found on the web..

[Amit_Alfaman]

Blew the head on the 2L Giulietta!!!

Stupid Branch caused the problem. Lost all compression cos the pipe on the 4th cyl outlet was blowing. It also burned all the wiring close to the branch.

[AlfaTipo]

First time I've seen this post. My first Alfa was a Giulietta. A 1.6 (in the UK).

I like the flat black car and the wide-body is terrific but the rear wing is a little lame.

Don't often come up in the US as they were not offered for sale but I could get into one.

Demolished mine on an off-ramp.