Recently we ended up going back to back on the dyno with two different headers on a mild k24 build. One header was a classic traditional big tube style 4-1 with no megaphone built by DTR(later known as SSR). The other was a Sheepey hood exit which is also a 4-1 style and incorporates a megaphone.
I guess it comes down to how you like to party.......and how loud you want that party to be.
The basics of this setup are as follows
- 12.5:1 compression 88x99 on e85
- Ported head on Cartel Elite 3.5's
- Skunk2 Ultra (4.5L)
Testing was done with the dump attached to the DTR unit. The hood exit was run as shown. You know, out the hood.
Blue line - Sheepey Hood exit
Red line - DTR 4-1
Some might speculate that the gains and shift in powerband can be attributed to the megaphone being part of the equation. Either way, it gained power.
Here is an old test we did comparing the Skunk2 Alpha header to the PLM Toda replica. When you're all motoring life away on a budget and need a shelf header, these 2 are hard to beat.
The basics of the engine are as follows
- PR3 Portlow head on Skunk2 Pro3's
- Modified PerformerX intake manifold
- 3 Inch Exhaust dump
- Hondata S300 on e85
RedLine is Toda Rep
BlueLine is Skunk2 Alpha
Tested on the same day minutes apart. No matter where we moved vtec or played with a/f and timing we couldnt get rid of the midrange lumpiness. I'll go ahead and assume its due to the cyl. pairing. Either way it rocked out on the very top end. The quality is real nice and it fits really well.
This was enough power to go 11.2@120 in a tin can EF.