Performance headers

[Spindrift]

With all of the posts related to modifying the 6.5TD for power, I'm surprised that there hasn't been much discussion, if any, on the advantages of performance headers. Am I off base here? I would think that the advantages would be exactly what the 6.5TD needs to last longer and provide more power. Lower EGTs, less backpressure and no EG reversion would seem to be the greatest benefits. Are our headers so good that no one sees the need for an aftermarket product?

[JoeyD]

I would think a custon set that mounts the turbo in the center of the motor to keep the runners the same length would help out. The cost will be sky high though and the power gained may not be worth it.

[Spindrift]

Forget about power...for a second or two. Given the damage that heat can do to these engines, the decrease in EGTs might be worth the cost.

[JoeyD]

I am not sure how much it would lower EGT. But I bet it wouldn't be a whole lot.

[kowsoc]

Interesting thought, but because the turbo creates a restiction to exhaust flow I don't think headers leading to the turbine will make much improvement. For a intake boost of say 10 psi the exhaust backpressure is probably 10 psi plus. However, on a naturally aspirated engine such as the 6.2, equal length headers would probably give benefits of scavenging and reversion to draw in the fresh charge of air that they give on a gas engine. On the 6.5 the intake is under pressure from the turbo to scavenge and fill the cylinders.

Just my idea... smile.gif

[Spindrift]

Originally posted by kowsoc:
On the 6.5 the intake is under pressure from the turbo to scavenge and fill the cylinders.Are you saying that the 6.5 has a certain amount of exhaust gas coming back into the cylinders, and it's because of backpressure?

[kowsoc]

Sorry for the delay...been too busy to check the page :rolleyes: . The turbines in the turbo are on a common shaft but are separated so no exhaust can enter the intake. The exhaust heat and pressure drive the exhaust turbine which in turn drives the intake side turbine to create the pressure to fill and scavenge the cylinders. This is why I think traditional header theory would not apply to a turbocharged engine but thanks for the interesting thought! smile.gif Inventions can always be helped along with a little discussion.

[DA BIG ONE]

Porting the turbine outlet, or installing larger turbo and larger dia. exhaust would give best gains in flow on a TD.

Worth while gains in flow using headers on a daily driver TD with its low rpm operating range is doubtful at best, IMHO.

However, I see that marine diesel company sells headers for their 300 hp 6.5td conversion, maybe they can chime in.