I have this O2 housing too and it is great!

 

Most tubular 02 housings will perform very similar, the real test is long term fatigue. We've had better luck with the Helix 02 housings in terms of long-term fatigue (the Helix units were out LONG before the ebay ones came out) and some guys have over 75K miles on these housings. That said, the investment cast ones are nice too if you have the cash for it, durable with decent gains - just heavier and a bit spendy.

Cheers,

Gary
Gruppe-S

 

The EBAY O2 provided some gains but only because boost was higher during that test. If the stocker was tested against the ebay unit at 20psi power would be identical.

 

Jeff,
Was this later revealed? This would certainly bring some light to the entire debate. I thought the results from Buschur was the light at the end of the tunnel...

 

No.

 

Attention to detail. He reported this in the tread but people were drunk with excitement and didn't understand the difference.

 

Ahh I see where he says

"The boost control is backed off all the way and it is running on the actuator only."

Differs from saying he was using a boost controller. This extra boost would make the difference. I was about to jump on you Jeff but after reading the details it is there...just have to read it a few times.

You would assume that less pressure on the wastegate and hotside from an improved O2 housing alone would make the difference, although the fact they toyed with the boost makes all the difference.

I personally have the Invidia housing. I like Ebay but not for everything.

 

ss autochrome the best!!! it also helps out torque also...

 

I actually had an ebay O2 housing on my car for about 6 months. I got sucked into it by all the people claiming faster spool and big-butt-dyno returns.

I dont run bleeding edge boost on pump gas. I keep the car around 20psi on an all-condition knock free tune. Before I installed the O2 I logged what my 60-80 times were and monitored spool (psi vs rpm vs load) as accurately as possible. After installing the O2 housing like the others I registered higher boost. The problem was alot of the boost was difficult to control. It would spike higher and creep in taller gears. It also varied when going WOT at different RPMs in different gears. My rock solid 20PSI (with top end slope) tune was replaced with a rouge boost curve that would cause timing pull in higher gears. From what I could tell the spool wasn't any better. It may have felt better initially because the higher boost spike but overall it sucked for pump gas. I played around with the tune for a few months and then went back to the stock O2 housing. The only difference I noticed was my boost curve was much more stable which makes me feel better especially when I'm road racing and hitting boost at various rpm levels in various gears.

For the record I don't know how adding an alleged high flow O2 would aid in boost increase. In fact is should be just the opposite. If you remove an exhaust restriction it should be harder to hold boost as the motor will have to move even more air to hold the same PSI.

 

Actually reducing exhaust back pressure traditionally results in boost pressure increases due to an increase exhaust gas velocity passing through the turbine wheel. On most cars by opening the exhaust you will see substantial boost increases, even to the point of hitting boost cut.

On the EVO with the Helix 02 housing we see slightly better boost response with about a 1-2psi gain in boost pressures at the intake manifold. When properly tuned this results in real performance increases.

Cheers,

Gary
Gruppe-S

 

..... when dealing with turbos that are pushing the limits of the exhausts capacity to move the spent gas but this is not the case on a stock turbo'd EVO. The factory O2 and aftermarket 3" exhaust have capacity well beyond that of the stock turbo.

Furthermore, boost doesn't equal power. Boost = Heat.

 

On the EVO exhaust system (assuming 10.5 hotside with a TD05 turbine wheel) the real problem is the ability of the turbine and turbine wheel to push exhaust gas out. This problem is compounded by the 90 degree then another 90 degree turn right after the exhaust outlet. The end result is substantial back pressure created by both the turbocharger and turbo outlet itself. Theoritical solutions to alleviate this problem are to run with a larger hotside (this is why gains are so pronounced with a 10.5 hotside) the other is to clip the turbine wheel and trade exhaust pulse energy for back pressure reduction. A third and less effective method is to open up the 02 outlet and downpipe. All 3 have been proven to work.

As for increases in boost pressure, the stock 16G wheel and housing when pushing say 20psi is nowhere near its maximum efficiency. Yes gas law does apply (thus causing diminishing power returns as boost pressure is increased) but air mass does increase as boost pressure rises at these levels.

Cheers,

Gary
Gruppe-S

 

I've been running the Helix o2 housing with the stock lower heat shield held on by the one bolt for around 65k miles give or take a few hundred with zero issues. My car has produced more power than others with similar mods, the o2 housing being the only modification to differ.

 

I have a question about the ssautochrome pipe. it doesnt seem to seal all up against my megan 3 inch Dp. and suggestions....?

 

Are the holes for the studs to go through the 02 housing off?