Every now and then, we have clients that want to do back-to-back testing on certain parts. Last evening, we tested two PLM headers on a K24 Integra; the traditional 4-2-1 header versus the 4-1 megaphone collector counterpart.

The engine setup is as follows:

K24
87.5mm Wiseco 11:1 pistons
Molnar H-Beam rods
PRB oil pump
ARP head studs
CR-V PPA cylinder head (stock, unported, running in single lobe configuration)
SuperTech valve springs/retainers
Brian Crower Stage 2 camshafts (8620 billet)
Custom center-feed intake manifold w/90mm throttle
4" cold air intake
3" exhaust
ID1000 injectors
Tuned by Derek Robinson with Hondata K-Pro on E85

The dotted plot is the best baseline test with the existing PLM 4-2-1 header, which netted 276whp / 199wtq.

The solid plot is the final graph with the PLM 4-1 Megaphone header, which resulted in 282whp / 197wtq.

All testing was performed within two hours, both setups tuned to maximum power.



The 4-1 surprisingly picked up substantially down low (where torque is really lackluster on the single-lobe configuration), but lost some in the middle. No amount of cam timing changes could recoup the loss in the middle compared to the long-tube 4-2-1 of before.

I would also like to note that the cam angle and fuel table curves changed dramatically between the two headers. The first pull on the 4-1 Megaphone with the existing cam angle map resulted in a 40wtq deficit in the middle, until things were moved around.

If you have any questions, feel free to ask.

Thanks!

- Derek

 

very helpful dyno comparo - cudos to you guys for the test. amazing how it shows the old adage where there is the shift in power band between the two headers.

 

Been forever since you've posted in the n/a section Derek. Thanks for sharing!

 

nice, was this done without exhaust--straight header v. straight header with megaphone

 

Great test. Very similar gains vs loss to when I did a Smsp 4-2-1 vs Myers 4-1 with a megaphone! Thanks for sharing

 

These tests were both performed hooked up to the client's 3" exhaust.

 

agree with slowsleeper, last time i saw or followed dereks stuff it was his dad's sick crx LOL ages ago

good stuff!


LOL @ 3,600 to 4,400

one day maybe 10yrs from now the 4-2-1 for better bottom end myth could be squashed LOL

 

Nice post. Comparisions are always interesting

 

nice back to back testing, interesting results