hey guys,
so im currently running an hks cast manifold with my s366.

I am going to upgrade and rebuild the turbo and the wheel.

thinking about doing a dual wastegate tubular manifold setup.

will i see any difference?
single gate vs dual gate?
whats better? what makes sense to do? should i just keep what i have?


thanks for any input!

 

one gate should be enough if wastegate runners are placed properly in manifold design. if it is not broken don't fix it. just my two cents.

 

Better boost control, less heat, lighter, ext. Heck, our 321 Race turbo manifold that uses dual MVS wastegates weighs just over 6lbs. Ditch the cast IMO...

 

Any power differences that I will see with a tube?

 

A ton of variables here. A craptastic tubular manifold may perform worse than your HKS. It could also crack. A top notch tubular manifold should allow for slightly better spool and maybe better boost control (do you have issues now?). Depending on what flow and power level you're talking, there could be room for improvement in overall power, but, for most street cars, I doubt it would be noticeable, let alone worth the time and expense.

 

100% agree with ^.

 

ok well that answered alot lol
500-530 whp.

so nothing too crazy,
also e85..

 

I guarantee that you could make more power with a good one. Half of the ones that float around on the forums are trash IMO. Especially from a well know company here on the forums. Oh well, you get what you pay for...

 

I had both cast and tubular. I am still and will always run tubular!!

 

What company is that?

 

We have gained 30 rwtq over a cast manifold with our tubular units. To be fair we also upped the downpipe size at the same time, everything else was identical. We did an evo a long time ago that gained about 15rwhp peak from just a tubular manifold on a stock turbo. No one has ever cracked a manifold from us either, so the debate about reliability is usually in the quality control. Boost control is usually a lot better on properly designed tubular turbo manifolds too. One big plus about tubular units is less heat soak to the block, and more space between the intake manifold and turbine housing.

 

He speaks the truth

 

as a rule of thumb i would agree with you lance BUT even the "pro" & "well reputable shops" around tend to build manifolds that,just to phrase it in a nicely manner, ARE JUNK. Anyone with a welder nowadays can make a manifold.

Personally,I would stick with a greddy or HKS tubular manifold. I am not saying that the ACTUAL good shops cant make a manifold better than that but they are more expensive & more waiting time

To the OP, the cast iron HKS unit is a pretty good manifold with some drawbacks.
Will you be able to tell the difference between the two ? probably, but not by much. BUT to be fair, in basic material properties you will see that the tubular, will be a MUCH better solution than the cast iron (given that the design of the manifold is made properly) Weight, thermal etc

 

No business makes a good reputation bashing other businesses. I just like to make sure people are at least aware of the truth.

I find much to agree with your posting. We've tried many combinations with turbos, manifolds, wastegate locations, and downpipe sizes. There's no real good formula but there's definitely a good division between someone racing the car and someone doing pure spirited street driving. There's not many cracked manifolds out there unless they're "out the door" ebay items.

Boost control and power increase we've found a direct relation. Low on spool and or power; I bet the wastegate/wastegates are not not in an ideal location. Proper sizing, placement, and multitude will make or break numbers.

One of the biggest flaws to Mazda's engineering was the short cast twin turbo manifold on the third gen. So Elliot, I can't agree enough that the twin turbo manifold needs to be thrown right out the door. Not only for performance, but for the main reason people need to rebuild, coolant seal degradation/damage.



Costas, you're fair in your assumption and I agree with you as I've seen the same things. This is why I sigh when some customers bring turbo kits to me as life's like a box of turbo parts, "you never know what you're gonna get."

We produce a manifold for racers that we call the VE-R series. It has calculated runner length, dual wastegates, and believe it or not even with our in-house ceramic coating weighs less than 7lbs all said and done. The latest changes might net VERY VERY close to 6lbs.

The best bet for anyone in the market for a turbo kit is to ask questions. There's no one setup for everyone. Never will we ever just come back with "X turbokit", there's much more consulting needed than that. Sometimes even after consulting with people there are still answers missing as they have no ideal purpose for the car. How could you expect a contractor to build you a house without knowing any details? Some companies go right along with it and I'm happy to see that some people are starting to recognize this.

Going fast shouldn't be easy, too many people the wrong setups or go bankrupt and need to sell their cars. Think twice, then consult a professional...