downpipe

[samtheman]

hello all, just starting my 1983 quantum 1.6 td build. What do you recommend for the exhaust? i know less back-pressure = happy diesel  . techtonics makes a nice looking 2.25" down-pipe but is it worth the $400?? are there cheaper alternatives? any pics of custom made pieces would be greatly appreciated

[theman53]

It is fairly easy to make your own if you can weld. A quantum is a dasher IIRC and they have the longitude mounted engine. It should be almost as simple as welding two 90 degree bends at the right angle to mate to the tunnel.

If it is as I think the pipe you are looking at is for the other transverse engines and you would be disappointed at the price as well as fitment.

[samtheman]

if i read right they do make a pipe to fit the longitudinal mounted engines on the mk1. but i suppose for that price its off to the drawing board . unfortunately my cash flow doesnt match my parts wishlist 

[manehfr]

i would say its the proper time to learn welding...  dont do it on inox its a litle more complicated...

[Dubdoc]

MY custom made piece.

[VW Smokr]

ASSuming you are re-installing this stock 1.6td back into a Quantum ('longitudinal mount'), and NOT trying to stuff it into a Rabbit/Jetta ('transverse' mount)... the o.g. Quantum downpipe doesn't look too bad except for the reducer ring welded inside near the flange that mounts to the turbo. I'd lay some welds on the outside of the pipe, and grind away most of that internal ring that really constipates the flow. You can probably get somewhat faster spool-up by creating a "megaphone", expanding from the roughly 2.25" pipe to a 2.5" to 2.75" to 3" diameter within the first foot or so of pipe past the flange, continuing the 3" section for another 2 feet or so, then reduce back to a 2.75' or 2.5" diameter for the rest of the system.

There is of course an abundance of sizes, styles, sounds (& bling, if ya' gotta have it) in low-restriction 2.5" in/2.5" out mufflers, if your choice is to reduce the overall droning and noise at certain RPMs.

Seems like an entire free-flowing streetable flange-back system could be built for way under $300. YMMV

J.R.
SoCal

[TimpanogosSlim]

My plan is to start by having a local independent exhaust shop fab me up a complete 2.25" straight pipe. I might talk to the fabricator about a 3" section near the front but i have some doubts about clearance past my lower brace and front sway bar for that.

if there is too much drone, then I'll see about having resonators or mufflers welded in.