[GTOGEORGE]

Originally Posted by charlie66

Im not guessing.

NEVER said you were!
You would know your header size.

GTO George

[73 TRANSAM]

These are my turbo headers. They’re 1.875 pipes. I only have one side but the other side is identical. It has a 2.5” crossover.

[GTOGEORGE]

Nice.....What kind of HP are you making?



GTO George

[Tom Vaught]

Originally Posted by 73 TRANSAM

These are my turbo headers. They’re 1.875 pipes. I only have one side but the other side is identical. It has a 2.5” crossover.

2" headers or 1-7/8" Headers do not actually have the exhaust flow area of a 2" diameter or a 1-7/8" diameter.

Most people assume that they do but that assumption would be wrong.
Pipe Diameter is based on the OUTSIDE diameter of the steel pipe (in a exhaust application). Then you subtract the wall thickness of the pipe you are using times 2.

So, 2.0" pipe: if you have a .060" wall thickness your actual flow diameter is 1.875" and if you have a .047" wall diameter you would have a 1.906" flow area.

So your Turbo Headers are 1.875" pipes so can I assume that you have roughly a 1.775" flow air for your tubes (assuming a .047" wall thickness)?

Or did you use .060" wall thickness tubing. Then it would be even less flow area.

Tom V.

[GTOGEORGE]

Originally Posted by Tom Vaught

2" headers or 1-7/8" Headers do not actually have the exhaust flow area of a 2" diameter or a 1-7/8" diameter.

Most people assume that they do but that assumption would be wrong.
Pipe Diameter is based on the OUTSIDE diameter of the steel pipe (in a exhaust application). Then you subtract the wall thickness of the pipe you are using times 2.

So, 2.0" pipe: if you have a .060" wall thickness your actual flow diameter is 1.875" and if you have a .047" wall diameter you would have a 1.906" flow area.

So your Turbo Headers are 1.875" pipes so can I assume that you have roughly a 1.775" flow air for your tubes (assuming a .047" wall thickness)?

Or did you use .060" wall thickness tubing. Then it would be even less flow area.

Tom V.

OK Mr. Obvious, I’m thinking everyone should know that BUT thanks for in info! LOL!


GTO George

[wbnapier]

Typically in the metal business round tube goes by OD and pipe is by ID.

Pipes are normally used to transport gases or fluids so it is important to know the capacity of the pipe, so ID is the pertinent measurement (e.g. schedule 40).

Tube is structural so it is sold by OD.

This is often confused.

Don't get me started on gauge. That one is fun... Lot's of different gauge metrics, and it changes based on material. Terrible system.

[charlie66]

Originally Posted by GTOGEORGE

Nice.....What kind of HP are you making?



GTO George

he made just under on low boost.1400hp

Turn it up Edwin!!

[Tom Vaught]

Originally Posted by wbnapier

Typically in the metal business round tube goes by OD and pipe is by ID.

Pipes are normally used to transport gases or fluids so it is important to know the capacity of the pipe, so ID is the pertinent measurement (e.g. schedule 40).

Tube is structural so it is sold by OD.

This is often confused.

Don't get me started on gauge. That one is fun... Lot's of different gauge metrics, and it changes based on material. Terrible system.

Thanks Mr Napier, for the additional words.

The Turbo Headers made by 455 Turbo (see Post #2 in this thread) were actually made using pipe with a lot of fitting required but they were "works of art" and well designed.

Tom V.

[73 TRANSAM]

The primary tubes are 1 7/8" OD. It was a tubing and not piping, my bad. It should be 1 3/4" ID. to a 2.5" collector.

[Tom Vaught]

No Worries. Tom V.

[charlie66]

Originally Posted by 73 TRANSAM

The primary tubes are 1 7/8" OD. It was a tubing and not piping, my bad. It should be 1 3/4" ID. to a 2.5" collector.

Wouldnt matter any way for what you're doing.

[charlie66]

Too many technicalities going on around here! lol

[GTOGEORGE]

Originally Posted by charlie66

he made just under on low boost.1400hp

Turn it up Edwin!!

WOW should be a 7 second car......how quick does it run?


GTO George

[charlie66]

Originally Posted by GTOGEORGE

WOW should be a 7 second car......how quick does it run?


GTO George

Hes not finished with the car yet. Trying for norwalk this year.

His motor made 1160 torque at 3800 rpm lol

[GTOGEORGE]

Originally Posted by charlie66

Hes not finished with the car yet. Trying for norwalk this year.

His motor made 1160 torque at 3800 rpm lol

Looks like a heads up race for me!!



GTO George

[charlie66]

Originally Posted by GTOGEORGE

Looks like a heads up race for me!!



GTO George

ill loc it in for ya George! haha

[73 TRANSAM]

It is not a 7 second car, that's for sure. It is a street car with a turbo on it. But with a built engine to properly support the power. I'm still not done with the car as I have to fabricate everything in this car. It made good power on the dyno but never ben in this car in 20 yrs. So if I can get it out this year, I will be happy! So no locking in with u George.

[GTOGEORGE]

I would love to put my car on a Dyno and see what the numbers are, this engine has never seen a Dyno. Even when my first engine was on the Dyno it had smallish headers with only 2 1/8” tubes! I have 2 1/4” now......maybe need to go one size larger pipes.


GTO George

[73 TRANSAM]

It was easy to see the power on the Dyno but I’m not sure how my car would like this much power on it. I’d like to actually drive the car as I Ibuilt it to be a street car. Also this is not on a Happy Dyno either! This Dyno break people’s heart as it’s always making lower than what they have expected.😁

[73 TRANSAM]

Also, the turbo setup doesn’t like the big primary tubes not like a NA or Nitrous motor. 1 7/8” will support a lot of power. Big tubes will just makes it laggier!