RB25DET standard manifold/external wastegate.

[R33JDS]

Hello all,

Im new to the forum and looking for some advise from the experts.

I recently got my hands on a standard exhaust manifold with a 38mm v-band welded off to one side, it only cost me £25!!

I've had to fit this manifold because the one that was on there had some nasty cracks, when I removed it and tapped it on the floor it split in two!! 

I have a feeling that the position of the v-band is going to cause some issues, to try and remedy this I ground out the centre partition between the two sides of the manifold. Im hoping this will help the wastegate vent all 6 cylinders. 

Can anyone shed some light on this for me? I don't want to do any damage to my engine!!

Edited May 23, 2019 by R33JDS

[KiwiRS4T]

Pics please! Are you planning to put a wastegate on the manifold?

[R33JDS]

33 minutes ago, KiwiRS4T said:

Pics please! Are you planning to put a wastegate on the manifold?

Thanks for getting back to me Kiwi, i was hoping to put one on but if it's going to cause major issues I will buy myself another manifold or make up a blanking plate.

i haven't got a pic of the outlet, but I ground down about an inch/inch and a half. Tried to flow it in the direction of the v-band.

[KiwiRS4T]

Well it all depends on your turbo - if you have the OEM stocker then you won't need an external wastegate and you can just blank it off against the day that you upgrade your turbo - but if you are never going to do that you could probably swap it with someone who needs it now.

[R33JDS]

22 minutes ago, KiwiRS4T said:

Well it all depends on your turbo - if you have the OEM stocker then you won't need an external wastegate and you can just blank it off against the day that you upgrade your turbo - but if you are never going to do that you could probably swap it with someone who needs it now.

Thanks for sharing your knowledge mate. I will be upgrading at some point so I'll probably blank it for the mean time. It's good to know that it will work for my future plans though, you've put my concerns away to sleep. Many thanks Kiwi.

[GTSBoy]

It's far from ideal where it is. They really need to be placed right over the top of the turbo flange area.

[R33JDS]

39 minutes ago, GTSBoy said:

It's far from ideal where it is. They really need to be placed right over the top of the turbo flange area.

I guess that's why I picked it up so cheap... If I were to use this in the future, would I see some horrible boost creep/ damage to the engine and turbo? It would only be used with a low boost applocation 7-9 psi.

[Dose Pipe Sutututu]

If you were to use that manifold,  I suggest you also install a flange for a 2nd gate to control exhaust pressure on cylinders 1 to 3.