Thread: In Between Shifts Richness

What guide is this Cliff?

X2

So I see now, modifying the K value is not a good idea indeed.

I guess the alternative to changing A/F ratios on a B14 will be to try to mess with idle tables, Injector latency, and actual fuel pressure.

I think the problem is with the 550cc injectors. They are the Deatschwerks ones, they basically take stock ones and modify them to flow better.

So with O2 sensor disabled (maps where turned down below 14.7), then adjusting the Latency, Constant (put them down as 370cc then as 259cc), I get 13-14 AFRs cruising no load. Shifts still go down to 12's. But that is more depending on the initial AFR before the shift. When shifting at 17:1 it goes down to 14 basically.

Adjusting the K value down to 190 I was able to get 15-16 afrs cruising, but leaned it majorly idling.

I did notice something interesting with no O2 feedback. I would be cruising at 13's and open throttle a little more and then it would go up to 15's. When with O2 adding gas it would start lowering the the AFR's. I guess it's part of the throttle enrichment table.

Another interesting thing was, I've never had my injectors shut off while using cruise control. When driving without cruise control, if you go down hill injectors should turn off and timing goes to 0*. At this point your not using any fuel, just riding for free. Now while on the highway with cruise, the AF's would go above 18.0 (AEM doesn't read about 18.0) which usually means the injectors are off, but the car did a weird jerk and timing still stayed at 40* or so. Doesn't sound right at all.

in reading this thread and the strong suggestion of dont adjust k value from those ive come to respect on this forum over the years, what is a good k value to use for someone like me who has adjusted it quite a bit already? t25, 550's. thanks. sorry if im jacking.

Use the standard formula to get your K value where it should be (and stay), based on old injector size vs. new injector size. Once you set that number, you should never touch the K value again.

Just set it to stock 298 value and good luck

Not good luck, happy tuning!

I'm not asking for you to do the math, I can handle that. But what's the standard formula....please?

K value for bored maf and 370cc injectors - SR20 Forum

A little research goes a long way