Wastegate options/positions, need your thoughts

[Casey-G]

Hey all, i have just completed tacking a majority of my turbo manifold together, i need your thoughts/knowledge on a few things i have been thinking about.


Here is the manifold:







(please take no note of the cleanliness of the manifold im getting it caustic bathed before i weld the runners fully)


Now what i'd like to know is weather or not it would be worth putting a port in for an external waste gate not and blanking it off for the future, as i will be upsizing the turbo in a few months. Or if i should just make this manifold to suit the turbo i will be using (internally gated) and not worry about the waste gate port? and just make a new manifold for the new turbo i get?

Another thing i would like to ask is what is a good material to use to make the collector out of? it needs to be reduced in size quite a bit. I was leaning towards using some fairly heavy walled 2.5" pipe and cutting it into quarters and doing it that way.

again your thoughts are appreciated.

[Draven]

no point making 2 manifolds... if you're going to be upgrading soon, put the wastegate option in. Actually, I would have suggested putting the bigger turbo on in the first place, but that seems to be a moot point.

I'd actually suggest trial-fitting whatever wastegate you're going to use, so the dump pipe doesn't hasve to be modded either. You can just blank both off, and when you change turbo insert wastegate.

Assuming the new turbo is interchangeable (another reason for putting the right turbo in there the first time around)

[NME308]

Hi there,
When my brother made the headers on our race car he simply used a piece of largish diameter steam pipe for the collector. He used the weld on turbo flange as a guide for the size i.e. inside diameter close to size of hole in flange, and outside diameter not so big as to foul the bolt holes in the flange.

Where your 4 pipes come together brother cut the touching edges on various angles to merge the pipes down to similar size to that of the above mentioned collector.











You can see in this next one where brother plumbed the wastegates out of the collector.



Hope this is of some help!

Cheers,
Jason

[Draven]

no offence Jason, but that's an ugly as sin job (esp the dump flange - dump). I know on race cars being pretty is not the primary goal, but still

[Casey-G]

no point making 2 manifolds... if you're going to be upgrading soon, put the wastegate option in. Actually, I would have suggested putting the bigger turbo on in the first place, but that seems to be a moot point.

I'd actually suggest trial-fitting whatever wastegate you're going to use, so the dump pipe doesn't hasve to be modded either. You can just blank both off, and when you change turbo insert wastegate.

Assuming the new turbo is interchangeable (another reason for putting the right turbo in there the first time around)

No well here's the thing, i have a brand new turbo off a late(ish) Evo it has a weird ex in flange (3 bolt) and a 2 bolt dump flange, i am yet to make the dump pipe and all, i am now thinking that i will make 2 manifolds as the new turbo will be much larger, and perhaps may need to be mounted differently.

NME308, thanks for the pictures, So i guess i just use the same material i have been using but cut them down smaller to make them all meet up to my desired dimensions.

cheers

[the_random_hero]

No offence, but that manifold is miiiighty messy...
If you have access to a cold saw with cut angle adjustment, it isn't too hard to make yourself a merge collector jig from some angle, some box steel and a few C clamps. I can draw up a picture to explain what I mean if you want later on, I have made a few merge collectors from a jig I borrowed in the past. If you don't want to go to this extent, I can get you a merge collector made from TIG welded steam pipe for around the $100 mark plus whatever it is for delivery.
As long as you know for certain the wastegate position is 100% going to clear everything from the radiator, turbo (future) and block, make preparations for the sucker now. Make sure where it's going to be fitted to is going to work (not like certain famous turbo manifolds you guys have probably heard of), ideally it will as close to the turbo as possible, angling towards the direction of the runners (not perpendicular and only taking gas from one runner like aforementioned manifolds).

EDIT: If the new turbo is completely different to the planned one now, forget most of what I've said. Make the two manifolds, although I think you're just wasting money not going to the 'better' size originally.

[Casey-G]

No offence, but that manifold is miiiighty messy...
If you have access to a cold saw with cut angle adjustment, it isn't too hard to make yourself a merge collector jig from some angle, some box steel and a few C clamps. I can draw up a picture to explain what I mean if you want later on, I have made a few merge collectors from a jig I borrowed in the past. If you don't want to go to this extent, I can get you a merge collector made from TIG welded steam pipe for around the $100 mark plus whatever it is for delivery.
As long as you know for certain the wastegate position is 100% going to clear everything from the radiator, turbo (future) and block, make preparations for the sucker now. Make sure where it's going to be fitted to is going to work (not like certain famous turbo manifolds you guys have probably heard of), ideally it will as close to the turbo as possible, angling towards the direction of the runners (not perpendicular and only taking gas from one runner like aforementioned manifolds).

EDIT: If the new turbo is completely different to the planned one now, forget most of what I've said. Make the two manifolds, although I think you're just wasting money not going to the 'better' size originally.

Cheers and thank you for the offer, but im quite experienced with a tig so i think ill make it myself, what im basicly getting at this is a first time thing, i'd like to get all the theory sorted and mostly applied (maybe not the gate this time) but you get the idea.

With the collector, by box section are you talking about like RHS or similar? why use a square material, when you want it well.. more circular than anything?

my original plan was to cut some 2.5" steam pipe up on angles to suit the turbo flange, so i guess in a way im with you, brobo is available to me so there's no real drama to how i need to cut it.

[the_random_hero]

Cheers and thank you for the offer, but im quite experienced with a tig so i think ill make it myself, what im basicly getting at this is a first time thing, i'd like to get all the theory sorted and mostly applied (maybe not the gate this time) but you get the idea.

With the collector, by box section are you talking about like RHS or similar? why use a square material, when you want it well.. more circular than anything?

my original plan was to cut some 2.5" steam pipe up on angles to suit the turbo flange, so i guess in a way im with you, brobo is available to me so there's no real drama to how i need to cut it.

I meant use the box section to make the jig for cutting the merge collectors. It is quite simple to do, I think the last jig took about an hour to make. Only thing you'll need is a rotation guide to make sure the pipe is getting rotated the right amount, but there are ways to get around this on the cheap if you have to.
I suppose I could also get the bits for the merge unwelded, not trying to force anything on your or advertise, just help if I can.

[NME308]

Some finished ones for you Draven...







Cheers,
Jason

[Casey-G]

I meant use the box section to make the jig for cutting the merge collectors. It is quite simple to do, I think the last jig took about an hour to make. Only thing you'll need is a rotation guide to make sure the pipe is getting rotated the right amount, but there are ways to get around this on the cheap if you have to.
I suppose I could also get the bits for the merge unwelded, not trying to force anything on your or advertise, just help if I can.

nah that's cool mate, i just dislike parts that i feel competent enough to make myself.
I understand what your saying with the jig, that quite a good idea and i think i'll use it, thanks.

i think i could quite easily do this now with that jig idea, give me the weekend and i'll report back with pictures.

NME308, why did he want the BOV's hanging out of the hood?

[Draven]

still not keen on that turbo flange exit, but impressive as hell engine bay (which I would love to own).

I'm privileged - Linden has done all the welding in my car, and it makes me bar up when I ogle it

[NME308]

NME308, why did he want the BOV's hanging out of the hood?

The car is Pro Street so a little outlandish is acceptable!
By the way I actually like the progress you have made so far. The fact that you have got in and done it yourself deserves kudos!

still not keen on that turbo flange exit, but impressive as hell engine bay (which I would love to own).

I'm privileged - Linden has done all the welding in my car, and it makes me bar up when I ogle it

Neither brother or myself are professional welders - he does a better job than I however so he got the welding gig! We'd kill for the funds (not literally) to have a professional do the entire job! Dunno where now, but there is 9 months of family neglect in that engine bay

Definatly love to ogle the professionally installed jobs too!

Cheers,
Jason

[Draven]

I didn't realise - full credit for an amateur effort.

I've just accepted that welding is something that I can do sub-averagely, but am willing to pay for it to be done perfectly.

Happy to take pics if you're keen on welding pr0n

[Casey-G]

The car is Pro Street so a little outlandish is acceptable!
By the way I actually like the progress you have made so far. The fact that you have got in and done it yourself deserves kudos!
Cheers,
Jason

ah cool fair enough, bit like the Armageddon burnout car for the army eh?


Thanks for the kind words man, i like the feeling when you complete something yourself and it works and looks clean.

done it yourself deserves kudos!

Maybe a little rep to?? haha well maybe (haha spoke to soon)

[NME308]

Happy to take pics if you're keen on welding pr0n

Please do!
It gives amaters like me something to aim for and a broader ideas bank to draw on.

Cheers,
Jason