3400 Manifold down pipe for Beretta

[3400-95-Modified]

Well, I've blown out my LAST donut gasket... It was time to redesign my downpipe to make it more perminate!

First, Start off with a 90* mandrel bent pipe. I used 41432, NOT the 41441 like pictured, the 32 is 2 1/2 OD on both ends.



Make sure you have a good welder.



Cut the 90 right about here.



Bolt your custom flange to the manifold and position the pipe and mark it. Tack it in two places, allows you to tweak it once you test fit it.





Once fitted tack it two more times at the two other quarters to lock it into position.

Bolt it to the manifold again and check for the lower bend. AMAZINGLY enough mine fit perfectly with no extra cutting... I marked it then tacked it.



Well seems to fit ok for now, and this is the difference. I haven't quite finished it and It's not in for good right now... I'll have to take the corsi to work tomorrow and finish it, but this is what I have so far.

The OLD





The NEW plus a pic of where the 3400 round gasket fits into.





There will be a flex pipe following the downpipe to allow the exhaust to flex and not break the manifold so no worries there.

[bjs96beretta]

WOW what a diffrence. you got some skills with the welder! very nice job. how did you know you blew the gasket? check light come on? or did you smell it? glad you got it fixed!

[3400-95-Modified]

put put put put from under the hood...

Wait till you see the finish welds on the new downpipe... I've improved tons from the old dowpipe welds... plus that was done with a smaller mig and me using a hand held mask... it's easier to run a mig with two hands.

[Rhedalert]

that is sweet!!! Where are you putting the flex pipe? I've been looking to make something like this for a while. My stock flange is not only small, but also leaks a little at the flex joint. I had a muffler shop weld a 2.5" pipe to the flange + flex joint but still, the initial ID is like 2".

[3400-95-Modified]

Flex will go where it has been since I did the 3400 manifold. I may buy a shorter one though... I'm not sure yet.

[3400-95-Modified]

Oh and for those that can have one made this is the flange I started with... I used solidworks to draw it from measurements I got from a stock one.