Hey bro! Welcome back. It's been a while. Sorry to hear that you haven't been able to remedy the fuel issue, but the wastegate issue is a simple one. The 38mm gate should be more than enough for the power you are looking for right now. I think that all you should need to modify is the direction of the wastegate tube itself. If the tube goes against the flow of exhaust then the wastegate won't work as well as it should. If you can redirect the tube towards the flow of exhaust you shouldn't have any problems at all.

 

Could you clearify this abit more? Do you mean the point where the WG tube connects to the collector itself? In this case I need to build a new longer collector that can support a narrower angle of the wg tube.

 

Still looking for more advice from experienced manifold builders/users.

 

To clearify I am looking for opinions on possible working solutions.
Would replacing the 38mm WG with a 44mm possibly be enough or is a completely rebuilt manifold required?

 

the angle of the wastegate should never exceed 45 degrees as a rule of thumb. but the better the angle towards the flow of exhaust the moer efficiant the wastegate will perform.

 

a full manifold remake is not needed at all.. at the very most just reposition the wastegate runner angle for better flow... if youre going for more power later on then the bigger wastegate will help then but youll still run into the same problems then if you dont do the runner anyway. i would say start with the wategate runner and find the optimal angle and then change to a bigger gate afterwards.

 

Exactly. Keep the wastegate as close to the turbo flange as possible,Keep the direction of the wastegate not less then 90 degrees and as much in the direction of flow as possible,and keep the collector as long as you have room for.

 

Ok, thanks for all the helpful answers. It seems to be the common understanding that the angle of the dumptube where it intersects the collector is the most critical spot. I will most likely try to change this, but that means building a longer collector, since the one I have now wont support any less angle.

So in my case this more or less means building a new manifold, which is OK, apart from the engineflange being a pain to fabricate with bad tools for it. I'll also look into if I just can fabricate the longer collector + new dumptube and extend the old manifold to fit it. Extending the manifold upwards towards the hood/bonnet is no problem space wise. The WG will most likely also be changed since it will be a pain if the rebuild still falls flat due to a small WG.

Ill post updates later this year when things hopefully went as planned.
Thanks.

 

good luck bro. i hope everything works out for you.

 

Okay, so university is done for the summer along with alot of other "have to do's",
which gives me time for the car again. The changes have started to get rid of the boostcreep from last year. It was not horrible but did prevent me from using EBC.

I have been living by the garage the past weekend, and some progress have been made, but distractions like gf and such did slow me down quite abit.
On top of that my phonebattery died so i only managed to get an early friday picture. This is of the manifold from last year. Instead of building a new merge collector, i decided to improve WG flow in the one I had.

Rough cutting the collector to insert smooth bends from the 2 closest runners.


Also done additional grinding inside the collector to improve flow to the WG port from the opposing two runners.
I am quite confident these changes together with the new precision 46mm WG will be sufficient. The manifold itself is done, came out great, I only need to fabricate a dumptube to the WG and connect it porperly into the downpipe.

Also did some changes to my fuelsystem, changing all my hoses i added as returnsystem last year to piping. (With the exception of a 10cm/4" flexhose to allow engine movement.)

Gonna work shifts for 4 days now, then I will have time off again to finish the car. Will post more pics aswell.