View Full Version : browntops , req_fuel, and inj per rev

11-16-2005, 04:50 PM
Got some browntops today. With greentops, I was running four inj per rev, alt, and req_fuel of 12.0/6.0.

When I put the BTs in, the thing ran BAD (overrich, I'm assuming). I then used a req_fuel of 9.0/4.5 (75% of 12/6) MT's calc'd req_fuel was 9.6, so I'm in the ballpark.

Car still sucked bad, but now overlean. Then I went to two inj pre rev, and it was horrrible. Upping req_fuel back to 12 (no longer halved to 6 since it's on two inj per rev instead of 4), made it idle well. Makes no sense to me to have bigger injectors and the same req_fuel, just because of changing inj per rev.

Am I running into weirdness because of injector opening time (1.0)?

What req_fuel are y'all running with browntops, and what are your VE's?

Many thanks!

11-16-2005, 06:51 PM
Got it running well enough at 12 to drive around. VexMe rules. That is all.

11-16-2005, 09:57 PM
with the 550's it's a bit rough since the idle pulse width is always below 2ms, usually around 1. i'm running 6.4/3.2 req_fuel but my ve bins at 200kpa are at 100. this is at 2 injections per rev


11-17-2005, 01:28 AM
on my B21ft, I have my reqfuel set at 24/12, with 2 injections per cycle, inj. opening time of 1.1ms, and at 100kpa I am at 48VE at 2800rpm, 62VE at 6000rpm, and at 200kpa 93VE at 2800 and 108 at 6000. I have it tuned for 87 octane, and have been running around 18-20psi boost. Honestly, I think I need to upgrade my MAP sensor 'cause 250kpa just aint enough :-P. I really don't think you need to be running 4 injections per cycle, that makes it pretty hard on the injectors at high rpms.


11-17-2005, 02:07 AM
I think I am running a req fuel around 11? or maybe its 13... with 2 pulses per rev

11-17-2005, 12:18 PM
Thanks guys!

I've left it at 12/2/alt, DC's at 200/6000 are about 85% :party: way better than the 135% I had before :oops:

Vexme made a lot of smallish changes, and I'm running it for the second time now. I think it's time to try the EGO mode.