Equal Vs. Unequal Turbo headers

[abustiffy]

A lot of people say Full race gets the bucks because they are full race. This is true to an extent. But they have built a reputation to earn these bucks by having top notch construction, great support and they dont just stick with a basic design. Their manifolds go through many revisions both in practice and in their designs in solidworks. These manifolds are about as good as it gets for a consumer product.

With that being said, Im not the type of person to go that far. Ill gladly leave 1% hp on the table to spend half the money (well really make it myself but that is another story). Im not a fanboy of them, but I do respect them as fabricators and engineers.

As far as pipe size. Many people love to use pipe that is too large in turbo setups, thinking they are doing good. We were building 302 ford v8 kits using 1 5/8" primaries and 2.5" crossover tubes. We decided to revise the design for many reasons to 1 1/2" primaries and 2" crossover. Guess what? on cars up to 500whp(we didnt make more than that though a customer supposedly did low 600s on revision) we did not lose top end power but we did gain rougly 3-500 rpm in peak boost from the same turbo. On some cars the decrease in time was even more dramatic.

 

[Toysrme]

Eh, it's a double edged sword with a turbo.
The larger the pressure differance on that turbine, the more power it's going to make. No exhaust after it = great LoL! & we all know that it can make big gains in power. That being said. There's alot of things that go along with what abustiffy said.

What people time & time & time & time again always forget. If your itnake is a hair restrictive, if your exhaust isn't perfect for peak power. If your turbo might make the powerband you want, but starts choking off (or say it doens't drop off sharply, but it looses power) abit before you want...
Run another psi, or two through it at higher rpm's.

Problem = solved. LoL!


Worst is a turbo log manifold. They do spool faster by a hair, but the power reduction compaired to a real turbo manifold is way off peak & beyond.

 

[abustiffy]

You would have to search for it if you cared, but an reputable Nissan tuner known as enthalpy on the boards took a nissan sr20det and went from a log to a full race tubular. At a low power point(300ishwhp), the car gained 30+ hp on the same tune. I think a non equal would have done close to what the equal did.

Edit. Picked up more

http://forums2.freshalloy.com/showthread.php?t=119879&highlight=jgs+log+full-race