Garage Storage Organization and Garage Cabinets

1990 shadow vnt · **T.U header vs Ported Manifold**

Title says it all.
Which is the better performer?
Which has better flow?
I believe the ported exhaust manifold flows 30% better than a stock one.
Does anyone have flow rates of these headers?
I am running a ported exhaust but would consider buying a header if the rate of flow is higher.
Thanks...............................ryan

tryingbe · 01:46 PM

Which is the better performer? - TU
Which has better flow? - TU
I believe the ported exhaust manifold flows 30% better than a stock one. - 10% if you're lucky.
Does anyone have flow rates of these headers? - Yes, Chris W have it posted on the board, do a search. - flow rates goes TBI header > TU header > ported exhaust manifold
I am running a ported exhaust but would consider buying a header if the rate of flow is higher. -Better start saving your pennies.

turboshad · 12-01-2006, 11:15 AM

This isn't a TU unit but it is the one I made and will have similar flow. The bottom one is a mildly ported stocker. I think the difference is pretty obvious.

DJ

88_Pacifica · 12-01-2006, 12:36 PM

Quote:

Originally Posted by Chris W

The TU header can be used in conjuncton with our 3" swingvalve allowing a 44% increase in flow in comparison to the 2.5" swingvalve with the TBI.

Chris-TU

Ok.. how about after mating a 3" SV with the TBI? Just curious what the flow's comparison is then....

88_Pacifica · 12-01-2006, 12:47 PM

^^ Nice then... +1 I had to make sure we were comparing apples-to-apples.

speeduphoria · 12-01-2006, 12:56 PM

Quote:

Originally Posted by Chris W

Due to where the header places the swingvalve it cannot be done with our 3" version. The swingvalve must be cut apart and rewelded with a 90 degree angle. The bend will reduce the flow numbers more.
Chris-TU

It can be done you just have to have more firewall clearance and place the turbo up higher

DodgeZ · 12-01-2006, 01:13 PM

Quote:

Originally Posted by Chris W

I'm sure that's possible but not everyone is willing to massage their firewall especially if their car is numbered. The TBI header we flowed was the version where the SV needed to be modified. Another design might provide different flow numbers.

Chris-TU

That's right. I wasn't going to bang in my GLHS's firewall to fit my T3/T4 turbo. I had to tweak the heater core coolant line to fit my huge turbo in the car. The 3" swingvalve and downpipe worked with only a little adjustment to the end of the DP (where the rod shifter was). Which in my case didn't matter because it was getting a whole new exhaust. The TU header is a LOT easier to install then a TBI. It prolly comes out about the same cost if you couldn't make the plate and weld the TBI yourself.

Frank · 12-01-2006, 01:25 PM

Also make sure that when you tap the stainless steel for the egt probes, you use a good tap. I ended up just having my machinest drill and tap them because he just so happened to have my block already and he wasnt going to charge me. The stuff is tough!

Frank

scott_s · 12-01-2006, 03:09 PM

Not all ported stockers are created equal. I had a self ported mani on my TII and then went with a ported stocker ported by someone else with more experience. My boost went up 1-2psi from 10-11 to 12psi, with the better ported unit. To me, that demonstrates reduced restriction, hence better flow.

The header DJ showed, increased his boost by 3psi over a ported stock mani. Showing an even greater flow increase. The mani was the only thing changed on his setup.

tryingbe · 12-01-2006, 06:49 PM

My boost goes up 1psi just because it's cold outside, does that mean anything?

scott_s · 12-01-2006, 09:00 PM

That is it cold outside?

Down in AZ, how cold can get it get?? We have been bouncing off -40C too much this winter.

I have noticed a boost increase in the cold as well. My 2 cents would be that you are using a spring controlled MBC. The cold causes the spring to shrink up a little. Enough that the boost level changes. A friend was tired of that happening. Here it would be more than a 1 psi increase in the boost level. He changed his MBC to ones with out a spring. No more problems for him.

In the cases, I mentioned the temp was pretty much constant from before to after.

tryingbe · 12-01-2006, 10:58 PM

Well, go from 120F to 45Fish... it's cold. Though, still have plenty of traction.

Oh yeah, we have track open down here all winter.

rfb6435 · 12-02-2006, 03:30 PM

Quote:

Originally Posted by Frank

Also make sure that when you tap the stainless steel for the egt probes, you use a good tap. I ended up just having my machinest drill and tap them because he just so happened to have my block already and he wasnt going to charge me. The stuff is tough!

Frank

Agreed, I broke my first Harbor freight tap when I did it. I finally got it out and was able to finish it with a second tap. It definately damaged both taps before I was done but I finally got a clean thread.

-Rich

Csx254 · 12-02-2006, 06:03 PM

Um, about the TU header, vs the manifold. How about durability of the TU unit? Are they known to crack??? I wouldn't mind investing in one, but I have heard from the wieght of the turbo, and excessive heat, that aftermarket headers crack....any opinion on this?

tkelly27 · 12-02-2006, 08:36 PM

thin wall or long tube headers can and do crack. TU's are neither thin walled nor long tubed, so IMO it should be plenty durable. Also I think for the price, if one broke the unlucky TD owner would make a HUGE stink about it on here. Not that the price is unreasonable, it's just more than most TDers pay for their whole cars.