HKS wastegate 40mm and 50mm inlet flange size ?
 

Does the stadard HKS wastgate (40)mm have the same bolt pattern as the 50 mm? My 40mm is creeping at high RPM and My AVCR is set at 20 for duty so the combo is not working well at holding 20 PSI. Will the 50 bolt right on to my mani? If it does not I think I will go for a big Tial if I have to do cutting.

Thanks

Steve

?

the inlet flange is the same for the 40 and 50 mm hks gates...

the outlet is different however. the 40 is a 2 bolt oval flange and the 50 is a 4 bolt square.

Thanks. The outlet is open so it wont matter.

Who was the the one claiming the 40mm HKS was enough?


-Ted

enough? Not sure what you mean.

I think that he means that someone said that a 40mm waste gate would be big enough, but it seems as if it isn't.

my hks 40 is enough to keep my t61 at 7psi.

It wasn't enough to keep my T4s at 15psi. God damn thing. The ol' bigger is better definetly applies here. Get the 50mm.

BTW the outlet on the 40mm HKS is in actually 36mm. Unlike the 50mm which is actually 50mm all round. It's a superior wastegate in my opinion, from personal experience with creep issues.

Although the 40mm does seem to work for some, it did not for me.

what manifold were you using?

HKS cast on an FC. Likely part of the problem for sure. With a nicely designed tubular I can see the 40mm working. That was my experience anyway. May not be everyone's.

ive got the hks cast on mine, were you dumping to atmosphere or back into the exhaust?

Atmosphere first, same problem, then I added a dump tube (~8in long) same results. Simply it could not handle it. I can't even remember how much testing and fiddiling I did. I thought for sure the 40mm was enough, but at higher revs 5,500 + the boost was climbing very quickly. Boost controller was fine, I really noticed the creeping when I went to the FMIC. I think it made the engine & turbo that much more effecient and it couldn't keep up. Dunno.

Where are my manners stealling a thread. The 50mm should bolt up to the manifold sub-zero. The inlet is similiar. It's the outlet's that are different between the two.

I'm about to install a cast HKS FC manifold, and this is good info. Will the 40mm TiAL bolt up? Will it flow better than the 40mm HKS? I've heard good things about them, and they're a little cheaper than the HKS gates.