hosrom_951

Word is that the Tial 46mm is the 'best' aftermarket wastegate

But since the 38mm performs the same (or does the same job) as the 46mm then what is the difference?

The valve is larger or the vavle body is larger? is the Tial 46mm worth the additional $200+?

Some idiotic tuner (sorry, performance supplier) here told me that there was no way in hell that the 46mm would fit the 944, since it is ONLY used by 6 cylinder+ turbocharged engines (which i know is BS since some of you use it).

Any fitment issues? (86 models specifically)

Tim, if you read this, i would be interested in your response......

special tool

Hosrom - I feel that you are slipping again... I don't believe that any tuner told you the 46 would not fit the 951. I think you are making this up to get a rise out of people.

You were heading in the right direction too. 1 step forward and 2 steps back.

Porschefile

A 46mm Tial will fit, but IMO it is WAY too large for most people's power goals. A Tial 38mm on our 2.5l engines is more than enough for up to ~400hp. Even some guys I know with 6cyl turbocharged engines of relatively small displacement (2.5-3.0L) use Tial 38mm wastegates for up to around 400hp. By adding a 46mm wastegate, you are going to cause a lot of unnecessary lag. True, it should flow better at higher rpm and boost, although it's kind of the same thing as saying a K29 flows more than a k26. A tial 38mm is more than enough, unless you want something ridiculous like 500+hp.

RogueM3

How will it cause more lag? It depends upon the spring or the Boost Controller...not the size of the wastegate. This is just able to release pressure faster when called upon to open.

-Richard

DDP

Agreed. Think of it as a head valve. The larger the valve the less it needs to open.

Hosrom, just search for some of Tony G's posts. He swears by the 46mm and black **** boost controller.

evil 944t

Horsrom,

A 46mm fits just fine. Tell that tuner if he does'nt stop giving you bad info, you'll give him 46mm where he does'nt want it!

Nismo_Freak

The wastegate would be better related to a BOV for the exhaust manifold.

The only issue with the 46mm wastegate is that you might end up reducing manifold pressure (read: turbine energy) to the point that the turbine slows and the wastegate then shuts. What you'd end up with is non-linear airflow characteristics and a worn out wastegate.

Personally I think 46mm is rediculously large for such a motor. People making 500+whp on slightly smaller (however higher revving) 4-cyl. motors use 38's. They have no issues with boost control at all.

Wastegate size should be in tune with the restriction of the turbine housing. Smaller A/r's built to spool the turbo faster require larger wastegates, and visa versa.

hosrom_951

You don't know what world i live in


I know it would fit our cars, but is it worth the $$? does it have better response or something than the 38mm or does it just support biger HP numbers?

BoostGuy951

Either you need it or you don't. If you don't need a 46, don't get one, it wont be any better than the 38. If you are getting boost creep on a 38, then you need a 46. I dont think that happens on a 38 until 500hp or so.

hosrom_951

Boostguy: Thanks, i was asking because 1) there is a big price difference, 2) The 38mm is said to be the low cost alternative to the 46mm 3) SFR include a wastegate pipe that slips on the exhaust system when purchasing the 46mm.....so i wouldn't really need it on a stock car and plan on 300-350whp upgrade in the future correct? the 38mm would be just fine?

BoostGuy951

Yes, you will be fine with the 38.

Jeremy Himsel

I have both. The 46 does not increase lag at all. Especially since I can get 15 psi by 3,000 rpm's every time. It fits fine but is a bit of overkill and I can't say it performs better then the 38.

David Floyd

I agree, I happen to use a 35mm Tial with a 1 bar spring with good results.

hosrom_951

David: Don't you mean 38mm?

NZ951

No, the 35mm has been out for years... Tial makes new sizes reasonably often, 40mm is the latest IIRC.