I\'ve been converting to single turbo since... well forever actually :-)
I got a new GT40R years ago at a bargain and was hoping to trade it for a GT35R or 500R. It never happened zo I took up tha challenge to go for the GT40R
In my queste for a good manifold I did not find anything that fitted of the shelve. There was always interference with either the chassis or something else.
Together with a friende/photowelder we \'engineered\' something ourselves.
The runners have been made up, now the wastegate needs locating.
Many wastegates on of the shelve maniflods point downwards. One of ther reasons I did not find my taste in the is that I want easy access to it. Mainly for tuning.
So here are some pictures of what I\'m currently working with.
- Although the turbo is a T4 divided, the 2 runners come together just before the flange. They will flow as one.
- the wastegate runner will be located in this chamber.
- there will be a long runner back to the downpipe (can\'t have a screamer in Belgium) so I figure this (large) volume will have a positive effect on the exhaust gasses leaving through the WG.
- the DP gasses will also function as a sucking force (much like a paint gun sucks up paint from the reservoir by passing high pressured air.
Any advise would very much appreciated in the form of pro\'s and con\'s, alternative options, pictures of similar manifolds with thesame concept.
Many thanks in advance
Could you joint the 2 manifold runners earlier than where they join now? I wouldn\'t think you venting much of the heat and exhaust gas from the rear rotor by having it in that position. I think the wastegate would work but the heat on the one runner would be greater than the other = not good
good point. As the tubes are only tacked for the moment some changes could still be made.
I have thought to have the wastegate runner put in between the 2 runners but there is little to no room left
with the WG flange now hanging in free air I might still try it that way.
Something like 10 years ago on my FD I went down the route of fabricating my own manifold and at the time used 40mm bore hydraulic seamless tube to make it up with a wall thickness of around 3mm.
I say this because it looks as though you have used normal exhaust tube for the runners and the downpipe, which simply will not take the heat that comes out of a Rotary engine also the flange onto the engine needs to be 10-12mm thick or it will warp
Sorry to tell you this but it would be worse to see you get this finished get it mapped then have to start all over again plus another mapping session because the manifold has failed and potential caused a fire
I hope this helps and that the material is thicker than it looks and that the pics of another manifold I had helps
Clive is 100% right tbh i experienced exactly what he describes compounded by the fact I wrapped the pipe also. Personally I now sacrifice on weight and use weld Ell\'s most industrial pipe suppy places can get them for you in either mild or stainless.
its 2mm thick stainless (304)
after the right routing is done I will have it reinforced to support the weight of the turbo (+extra hangpoint for the turbo as well.)
That w/g position is going to creep like a maniac! Trust me I\'ve built so many manifolds I can\'t remember them all. W/G runners need to be in the direction of flow, not at right angles. If you are going to run at right angles you will need dual gates. I even had a single 60mm creep on me designed similar to what you have( had a bigger collector before flange even, which does help).
waht would be better then? Put the WG runner in between both exhaust runners with an upwards angle and then try to return it to the WG flange?
have you got some example pictures?
Thx
Not a very good pic but you\'ll get the idea I had zero boost creep with only a single 38mm wastegate on the 20b but all three wastegate feeds were taken from the outside of the bends where the natural flow would take the gasses when open.