Originally Posted By polyspheric
A well-sorted example of the "headers look good, but the results are disappointing": all the 1,000+ HP LSX engines out there using the original truck manifolds.
Same is true for up to about 700 HP on the Toyota 183" 2JZ engine: a cast manifold is really close to the hand-fab $2,500 header, and lasts 10 X as long. Mine is made by SPA in Brazil.



What else favors cast instead of tube?
1. much lower underhood temperature
2. less lost heat energy reaching the turbine inlet


Totally agree.
This is why I am building me a semi-log style patterned after
the LSx factory manifolds and making them out of schedule 40.

Just gotta get my compression whoas’ figured out.

"Old" member Registered: Sep 2001
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