Td06-19c ...what Size Wastegate?

[sleak]

I have a TD06-19C on an RB20 and I have a HKS style wastegate which is 38mm in size. It wont hold boost. Have tried disconnecting the avcr and just running it from a pressure source tot he bottom of the wastegate and it still wont stay at any level. I figured it was just the crappy wastegate (it came with that wastegate/diff turbo) so I bought a new one and wanted the same one so I didnt have to change the manifold and it still wont hold boost. ahh.

Any thoughts on what it could be? wastegate too small to hold boost? I only want to run 1 bar.

Thanks.

Rhys

[Risking]

So I asume its loosing boost??

If the wastegate is to small the turbo will actualy over boost as the excess exhaust gas can't get out of the manifold fast enough due to the hole being to small.

Id say its a dodgy wastegate design perhaps.

[Waldo]

umm.. note HKS "STYLE" so its cheap ebay one...i would never use a cheap wastegate...controlling boost is probably the most vital thing for your engine so you dont blow it up...lol..

[Cubes]

If the wastegate were too small then it would creep boost, not loose boost.

[sleak]

When i said wont hold boost, I meant it is gaining in pressure. it never holds a boost steady, just winds up from 4000rpm till I stop it.

the wastegate has held .8bar with a t3/4 turbo that was on it before, I would have thought that it would be big enough to hold / control boost with the td06 as it has a smaller exhaust housing, I do realise it would flow alot more then the old turbo but still didnt think I would have a problem with size.

I dont feel like forking out $1000 and all the hassel of taking the exahust manifold off then on again when it may not be the problem, although it is looking like it.

can anyone confirm or deny whether a turbo of this size would need a bigger wastegate or not?

or anyone have any other sujestions for me?

Thanks.

Rhys

[Cubes]

You need a larger wastegate if you are experiencing boost creep.

It may be partially due to the manifold design who knows, testing is the only real way to find out.

Edited January 9, 2006 by Cubes

[Sydneykid]

38 mm wastegate should be plenty big enough. What manifold is it?

cheers

[R31Nismoid]

agreed.

search button - re wastegate sizing... but that isn the issue here.

I betting manifold too, exhaust fiding it easier to go out the turbine than down to the gate.

Always the first thing to head for with rising boost above the spring

Speaking of which, what spring is in the gate?

Or is it one of the horrid adjustable things?

[sleak]

I believe it has a .9bar spring. but it goes over that!

when you sat testing is the only way, test what?

it is a custom manifold. if it is the manifold, then thats a big problem! stupid car!

Thanks for your input guys, I will look into some other things and well if its manifold, then it will prob stay liek that cause im not buying a new one!

Thanks.

Rhys