Author Topic: Home Made Down Pipe (Read 2691 times)

ein bora · « **on:** January 16, 2009, 04:06:00 pm »

Well I'm going to try and make my own down pipe, I have numerous 3" pipe and U-bends left over from a previous project http://img.photobucket.com/albums/v518/truszip/clip004-1.jpg
So I thought why not take the converter out and start getting things ready for some engine mod's. What I have is a down pipe from an old 1.6 n/a that I once had and was wondering if I could use this for the flange. Are these interchangeable with the 1.9 IDI's. I figured cut the flange off, hole saw a 3" opening and start from there. Sound about right??

Rabbit TD · « **Reply #1 on:** January 16, 2009, 04:22:22 pm »

Quote from: "truszip"

Well I'm going to try and make my own down pipe, I have numerous 3" pipe and U-bends left over from a previous project http://img.photobucket.com/albums/v518/truszip/clip004-1.jpg
So I thought why not take the converter out and start getting things ready for some engine mod's. What I have is a down pipe from an old 1.6 n/a that I once had and was wondering if I could use this for the flange. Are these interchangeable with the 1.9 IDI's. I figured cut the flange off, hole saw a 3" opening and start from there. Sound about right??

I'm thinking about the same thing for my 1.6 T/D so I'm gpnna watch too, I just got a mig welder for Chrismas and want to play

TurboJ · « **Reply #2 on:** January 16, 2009, 04:47:30 pm »

You really should cut starting from the flange that connects to the turbo itself (I hope that is what you were referring to).
If you use the stock cast iron 'twin bend' to start your downpipe, you won't get all that much out of your new DP as the first couple of bends will cause quite a lot of flow resistance.

And yes, 1.6 and 1.9 DPs are interchangeable.

dieselherb1 · « **Reply #3 on:** January 16, 2009, 07:49:03 pm »

If you attach your downpipe directly to the turbo, you will need to install a flex line inline to absorb vibration. I plan to do something like you're idea. I have 3 TDs to install into caddies.

regcheeseman · « **Reply #4 on:** January 18, 2009, 12:56:45 pm »

Quote

You really should cut starting from the flange that connects to the turbo itself (I hope that is what you were referring to).
If you use the stock cast iron 'twin bend' to start your downpipe, you won't get all that much out of your new DP as the first couple of bends will cause quite a lot of flow resistance.

Agreed - waste of time

3 inch may be too big straight off the turbo - it will not fit.

boosted_diesel_84 · « **Reply #5 on:** January 18, 2009, 02:20:55 pm »

Quote from: "regcheeseman"

Agreed - waste of time

3 inch may be too big straight off the turbo - it will not fit.

Passenger was making 3" DP for a while they claim it makes a k24 spool like a k14 and it fits in all mk1 and later applications iirc

regcheeseman · « **Reply #6 on:** January 19, 2009, 02:20:49 pm »

Yep - it'll fit on the K24 - nothing smaller though, The pitch circle of the flange mounting bolts is about 3" on the smaller turbos - there is no possible way to bolt it up.

Bolting up a 2.5 inch is tricky.

only need a few bits to make a pipe though...

Jettagli16v · « **Reply #7 on:** January 19, 2009, 03:25:44 pm »

regcheese is right:
You cannot go any bigger than 2.5" directly to the turbo, but you can flare up immediately from there.
If you want to buy a piece to make it easy, ATP sells a flange:
Part # ATP-FLS-029 which fits T31 compressor outlets (TD T3, maybe KKK)
which bolts to the turbo and brings it to a 3" V-band.

For what it is worth..
Many here love to make flanges, but I like to buy them.

They can also make it in Stainless, if you like.