Bigger exhaust manifold for a 1Y

[caveman]

has anyone tried fitting a larger,dual outlet exhaust manifold on their 1Y ?
I believe i have the potential to produce more power, but have gotten to the point
of too much restriction at the exhaust end.

[weldore]

im putting a 1y in mine when the weather is better and was thinking of leaving the original manifold from the 1y on and changing the flange on the 1.6 exhaust to fit then in the not too distant future i can fabricate a new exhaust with a larger bore without the hassle of removing the manifold.

[caveman]

I used the manifold that came off my 1.7 KY because otherwise i would have had to weld up a new downpipe, which i didn't have time then to do. Thing is that manifold outlet is small - maybe 1 1/2 ". I will be fabricating a freer flowing plenum intake manifold [more air+more fuel= more power] but before i can get all that air in i have to be able to get it out.

[weldore]

yes i had a look at the 1.6 manifold and it is one hell of a lot smaller and i also am thinking that there will be not enough flow.but in saying that alot of people have commented that its fine... so what do you do? just swap them over and never know if you have the power you should have ,or make the job a good one the first time round ? i would prefer to keep the manifolds that were designed for the engine but ive read some conflicting reports of the inlet fitting and not fitting...so i wont know untill ive got the 1.6 one off to see just how different they are...and as we have 5 inch of snow at the moment i wont be laying down in that, so itll have to wait

[caveman]

Right now the injection pump i put on has a modified governor, a larger head, and a couple of other things to give more power. I am sure i am close to same power as a 1.6 td. The potential for even more power is there as the next step would to put on an even more modified pump, but before that i need to be able to get more air in and out .

[camper]

I replaced the 1.6td engine for a 1Y.The 1.6td exhaust pipe was refrabricted to fit the silencer +extra metal added on its flange to bolt up to the 1Y exhaust manifold.The bore size of the down pipe seems about right.I can use this as a pattern to take to a exhaust pipe maker to make up in stainless.

[weldore]

so the 1.6td must be a wider pipe than the 1.6d...ive not done any measuring yet but by eye it looks around 8-10 mm smaller diameter than the 1y..gonna have a play this weekend as i have a spare downpipe,get the welder out and put some more holes in me slippers

[caveman]

First of all my problem is that it really wasn't a 1Y it was an ADG industrial engine, so perhaps it was never meant to run more than 3000 rpm's and so had a smaller than regular exhaust manifold . When i compared the ADG one with the KY one there wasn't much if any difference , there fore i wasn't about to weld a new flange to my downpipe.
Weldmore, it would be interesting to know what the difference is between a 1Y downpipe and a 1.6 TD one. That would tell us whether the [factory determined]flow are similar.

[weldore]

well as camper says theres not much in it..but my 1.6d pipe looks like a pea shooter in comparison

[caveman]

Vag cat lists the same muffler for the KY CS and JX so at least they are the same. But whether that is enough for a big breathing 1.9 is the question. I know it'll work -it's what i have, i'm just trying to figure out what will work if and when .
Do you know any model VW that had both the 1.6 TD and a 1Y. That would be the key.I tryed looking on Vagcat, but it's a bit hard to sort it out. We never had the 1.9 non turbo here in North America.

[weldore]

i think the golf mk3 had both

[weldore]

well both engines are in me shed waiting for the change over so hopefully by next weekend ill have sorted something out on the exhaust.made a couple of flanges at work last week....if anything itll get me off the sofa

[weldore]

i know this is an EXHAUST manifold thread but ive looked at the inlet manifold and i cant see the point in porting it to match the 1y head,fair enuff it would be nice for the parts to mate up perfectly but you cant port all the way through the manifold so,as i said, it seems pointless.

[caveman]

Yes you bolt it right up and it would work, but if you could take the same type of manifold but matched to it's respective motor, using the 1.9 "D" shaped port on an older head, it will produce so much turbulence, it may actually case some power loss. It not the shape of the manifold tubes but where they interface that is the issue. That extra air banging up against the face could cause the air below to enter properly.

[weldore]

but the holes on the 1.6 inlet are smaller than the 'd' shaped ones on the head so there shouldnt be any turblance as the air would flow straight into the head with no problems albeit with slightly less flow due to the size of the manifold..i think