the cheapest fuel system to achieve 10 psi on a turbo Kl !!

BATTOSAI · Post by **BATTOSAI** » August 30th, 2005, 8:30 pm

When I decided to swap my K8 to a Kl, there were a few parts missing on my package: I didn't had the Kl Ecu ,the Kl Vaf and the Kl manifold. I assume that the K8 manifold on a Kl is a power robber, so it must be on a Turbo Kl!! I was able to run thecar right thanks to the Apex'i s/afc, althought there has been a lot of talk if it works or doesn't on a k powered mazda. I don't know if it's a particularity of the 92 K8 gs ecu, but I can tune the fuel curve at both low and high Rpm's perfectly. I can even stall my car with it! When I rode the n/a Kl powered mx3 at first, I found out that the car was super rich. I leaned it at a -20% setting on all the Rpm band and only used one thrttle map (you can build two maps depending on throttle %) and that way the car ran really smooth and pulled really hard. Once I installed the turbo system on the Kl base, I installed my 255 walbro in tank fuel pump, and the car felt really rich. Then I built a map where I leaned all the rpm range to the maximum I could, which was a 50%. Then the A/f gauge was able to do full sweeps to both rich and lean at idle, which tells that it's in a good ratio. I did that in order to found a good Fmu ratio before dealing with the S/afc, because I didn't want to fell really rich like I did on my K8t. I tested the 10:1 Fmu and it was very rich until 7-10 psi, where the ratio felt at lean very fast. So I turned down the boost to 5-7 psi and lowered the Fmu to a 8:1 ratio. That way the car reacted a bit faster and didn't feel so rich. then I played with the S/afc. I set the throttle points at 30% for low throttle and from that point to 100% high throttle. I started to up the fuel curve at 2.500 rpm's and ended with a 15%+ at anything past 5.000 rpm's. It wasreally rich,so I started to raise the boost. Last night I hit a perfect and constant 10 psi from third gear to fifth and the a/f ratio meter didn't fell below the middle of the rich section of the gauge. No pinging, no overheating, just one of the largest smiles I ever had on my face!!! I have never rode anything that fast!!

nope-mx3 · Post by **nope-mx3** » August 31st, 2005, 2:23 am

Then imagine how it would be if you had used a Megasquirt

I`m pretty sure you could have tweaked out some extra hp that way, and also got rid of a lot of stuff. VAF/MAF etc.
s/afc is a "bad" way to tune the car. A real standalone would definetely be best.
And, it`s also cheap too, a lot cheaper than the S/AFC (or so I believe).

nope-mx3

BATTOSAI · Post by **BATTOSAI** » August 31st, 2005, 4:00 am

but for what I have read and heard , there is a lot of hassle to make it run right. I also loves the look and features of the S/afc, but for sure that I would decide to go to higher boost i will consideer installing one, because of the adjustable ignition timing capabilities and ability to handle significatively larger injectors,but for the 10 psi I set as boost mark is enough. Well, if the Ms is cheaper than the S/afc I will call the post " a different fuel system to achieve 10 psi on a Kl"

babyblueMX3 · Post by **babyblueMX3** » August 31st, 2005, 7:36 am

you running 220cc on 10psi ?

BATTOSAI · Post by **BATTOSAI** » August 31st, 2005, 3:05 pm

it seems imposible but I do! As they are the only injectors I had I started to search for their limits step by step. I won't force them any higher. After that I have two ways to go, I have 6 nissan sr20det injectors and a 034 efi additional injector controller. I started to build a Kl manifold with the 6 additional bosch type injectors mounts last year, but it is a lot of work!!

hppwdn · Post by **hppwdn** » August 31st, 2005, 4:00 pm

You mentioned you didn't have the KL IM. Did you get the injectors from the KL IM? If you are running the injectors from the K8 IM those are only 170cc. We figured that out when we did my swap and I was stuck with a K8 IM for a couple weeks.

babyblueMX3 · Post by **babyblueMX3** » August 31st, 2005, 4:25 pm

BATTOSAI wrote:it seems imposible but I do! As they are the only injectors I had I started to search for their limits step by step. I won't force them any higher. After that I have two ways to go, I have 6 nissan sr20det injectors and a 034 efi additional injector controller. I started to build a Kl manifold with the 6 additional bosch type injectors mounts last year, but it is a lot of work!!

I would change real soon injectors if I were you.
You should be near 100% duty cycle. You're not suppose to go higher than 80% DC or you injectors could crap on you. You don't want that to happened

custom101 · Post by **custom101** » September 1st, 2005, 9:23 am

I'd also consider getting a wideband to see exactly what your AFR's are. Don't put too much faith in those sweep gauges.

nos92mx3 · Post by **nos92mx3** » September 1st, 2005, 10:57 am

You also have to remember , that those gauges/your o2 are configured for NA, Not turbo. So the 2 bar green would be around say 13-1 afr Which Is lean under 10 lbs of boost.

BATTOSAI · Post by **BATTOSAI** » September 1st, 2005, 1:02 pm

You mentioned you didn't have the KL IM. Did you get the injectors from the KL IM? If you are running the injectors from the K8 IM those are only 170cc. We figured that out when we did my swap and I was stuck with a K8 IM for a couple weeks.

I am using the Kl injectors right now. I had to check it twice because I was going to install the K8 ones!!

You should be near 100% duty cycle. You're not suppose to go higher than 80% DC or you injectors could crap on you

You are right. Is because of this that I have lowered the boost to 6-8 right now.