|View single post by Judson Manning|
|Posted: 07-16-2006 08:29 pm||
|You can actually get down to 28mm chokes in a DHLA45 and up to 36mm in a DHLA40.
Choke size determines maximum amount of flow (assuming the head is breathing to its maximum capability). For a 2.0L engine you need the following choke sizes to produce maximum flow at the designated RPM:
5000rpm = 32mm
6000rpm = 35mm
7000rpm = 41mm
8000rpm = 46mm
SCCA E-prod rules mandate the 34mm chokes, and I can confirm even with a ported head, free-flow exhaust and high-lift cams, the 907 doesn't produce any power over 5500rpm.
Stock JH chokes are 35mm and 37mm for the 2.2 variant. For street use, I was happy with 34mm in the 2.0 and currently like the 36mm in my 2.2. Top end suffers a little, but low-end throttle response is fantastic.