VWDiesel.net The IDI, TDI, and mTDI source.
General Information => Upgrades (non engine related ) => Topic started by: ashleyroe on November 04, 2009, 07:41:59 am
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so a big discussion broke out in my build thread on the 'tex about putting a header on a diesel.
i posted up a eurosport header that i have been eyeing for both my cars for quite awhile.
as i recall i remember seeing a thread here, something along the lines of, "how to make my 1.6 n/a quicker"
and i remember seeing a small list including, injection pump, gov mod, fly wheel, and exhaust/header. (forgive me if i'm mistaken)
now i have everyone telling me this is a terrible idea on a diesel.
problems being: diesels shake too much and will break welds in the header & it depleats backpressure that diesels need.
any insight, advice, input, knowledge, experience, would be greatly appreciated.
thanks :-*
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You will need some sort of flex coupling after the header. I don't think you will have any worries about back pressure.
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I remember stumbling across someone mentioning that they had to fabricate some variety of bracket that attaches to the collector and to the engine somewhere.. This was to help support the header and keep it from both cracking and breaking loose.. I would imagine that with a quality header you'd be fine with a the earlier mentioned flex coupler...
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but remember, diesel engines move alot more in the engine room.. they twist quite a bit. the flex coupling is mandatory. i think the brackets to the block arent a bad idea either.
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so i just shouldn't bother.
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Depends on whether or not you want a header.
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On my NA ANYTHING I did to increase its breathing was worth it. If it is in budget I would definately do it. I ran 2.25 or 2.5 inch exhaust the entire way after the toilet bowl and it ran great. I had no issues or wishes that I had more back pressure. Really you never want back pressure, you want velocity.
Here is what I did to the intake as well :D
(http://c1.ac-images.myspacecdn.com/images01/11/l_9c1d854984f3564512bce9fe5d1c5fd4.jpg)
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I used a stock 8v gti 4:2:1 setup on my NA (mind you it is a 1.9). I imagine it will crack one day but it will on a gasser eventually anyways.
Unfortunately I couldn't do a back to back comparison because I didn't have a complete exhaust prior to installing the manifold as some of you may remember. I am curious as to whether or not the reduced backpressure has lowered my fuel mileage due to lower cylinders temps. I do get around 5.4l/100kms though, which is ok.
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so a big discussion broke out in my build thread on the 'tex about putting a header on a diesel.
i posted up a eurosport header that i have been eyeing for both my cars for quite awhile.
as i recall i remember seeing a thread here, something along the lines of, "how to make my 1.6 n/a quicker"
and i remember seeing a small list including, injection pump, gov mod, fly wheel, and exhaust/header. (forgive me if i'm mistaken)
now i have everyone telling me this is a terrible idea on a diesel.
problems being: diesels shake too much and will break welds in the header & it depleats backpressure that diesels need.
any insight, advice, input, knowledge, experience, would be greatly appreciated.
thanks :-*
Diesel's don't have much, if any, valve overlap so "backpressure" isn't really an issue, pretty much make it breath as good as you can.
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our diesels have something like 11* NEGATIVE overlap, so no, backpressure should not be an issue.
that being said, there is a point of diminishing returns.
I think that anything built for a gasser exhaust wise is probably not past that point.
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so a big discussion broke out in my build thread on the 'tex about putting a header on a diesel.
i posted up a eurosport header that i have been eyeing for both my cars for quite awhile.
as i recall i remember seeing a thread here, something along the lines of, "how to make my 1.6 n/a quicker"
and i remember seeing a small list including, injection pump, gov mod, fly wheel, and exhaust/header. (forgive me if i'm mistaken)
now i have everyone telling me this is a terrible idea on a diesel.
problems being: diesels shake too much and will break welds in the header & it depleats backpressure that diesels need.
any insight, advice, input, knowledge, experience, would be greatly appreciated.
thanks :-*
Your concerns about cracking are right, and others having expressed the need for more flow are also VERY right.
One of the few regrets I have over the years is NOT putting an exhaust system on a 1.6NA. I have done headwork and got fantastic results, and at that same time, I was making exhaust stuff for my gassers that would EASILY have bolted up to the diesel, but life got in the way.
What I used to make was a 1.5" set of secondaries for the gassers that used the early 4:2 stock exhaust manifold. I made an adapter plate that bolted to the exhaust manifold 6 bolt flange, and had two holes on either side to hold through bolts with compression springs on them. The adapter had a spherical countersink machined in it (I just made a cutting tool and bored each side from a 4 jaw chuck on my lathe) and the top end of the two secondary pipes ended in little bushings made of pipe that had matching male side spherical ends. Another flange was slipped over the "down" side of the secondary pipes and pushed against the backside of the end bushings, held in place against the flange with the two bolts/springs on either side of the flange. This allowed the engine to move freely in the mounts. The reason that is so critical is that the required length of secondaries is considerably longer than the stock bits, and the system merged into the final (2.25") collector just ahead of the A1 shifter box. IF you were to do this, the exhaust system has to be very free to move fore and aft, as that is where the resultant direction of the ball joint being right at the head comes.
I think you could find commercial 1.5" ball joints, and just weld them in and fab up the secondaries behind them, but I don't think there is enough room for any I have seen (secondary pipes too close together).
If you get the idea I am trying to encourage you to do this, that would be correct.