S-AFC 2/GT2530/450cc setup problems

[mikesim]

ok, after blowing the head gasket, my friend and i got around to fixing the car and adding my turbo, afc and injectors.

the injectors are DSM 450cc, and fit in just fine after exchanging the o-rings from the stockers.

i added the DSMs to feed fuel for the GT2530 turbo.

i followed the wiring directions from the PDF on the website, and without much more info, i setup the car as 4 cyl, throttle up (0-5V), and hotwire 7 in and 7 out. i also took -5% at 800rpm on the low and high throttle maps.

now when the car is cranked, there's no indication of movement on the RPM signal on the AFC or on the cluster, and it doesn't start.

could it be flooding? or could there be something wrong with the sensor? or is the #of cylinders correct cuz its direct ignition? i've double checked the wiring already. the wiring is crimped together with a VS3 tool. (ideal for cutting, splicing and tieing two or more wires together in one simple crimp.)

[c-rad]

Still sounds like a wiring issue. Did you make sure to hook up both grounds to the SAME ECU grounding wire an inch apart? That and wiring the AFM signal backwards are the two most common mistakes.

[mikesim]

yea, i've installed the AFC before, but i'll double check the AFM wiring. the grounds are a little more than an inch apart, but i think it's ok?

[capwred]

ok, after blowing the head gasket, my friend and i got around to fixing the car and adding my turbo, afc and injectors.

the injectors are DSM 450cc, and fit in just fine after exchanging the o-rings from the stockers.

i added the DSMs to feed fuel for the GT2530 turbo.

i followed the wiring directions from the PDF on the website, and without much more info, i setup the car as 4 cyl, throttle up (0-5V), and hotwire 7 in and 7 out. i also took -5% at 800rpm on the low and high throttle maps.

now when the car is cranked, there's no indication of movement on the RPM signal on the AFC or on the cluster, and it doesn't start.

could it be flooding? or could there be something wrong with the sensor? or is the #of cylinders correct cuz its direct ignition? i've double checked the wiring already. the wiring is crimped together with a VS3 tool. (ideal for cutting, splicing and tieing two or more wires together in one simple crimp.)

ok first off i just put my safc2 in and i set it to 4 cyl, throttle up (0-5V), and hotwire 7 in and 7 out.so your fine there.but did you make sure to put the brown wire (ground)before the black (ground).its nothing in the safc that could cause it to not crank.so i know you have checked the wiring but do it again.from start to finish.when i put my hks turbo timer in i could have swear i done it rght but i missed one wire.and i checked it more then once. good luck with it .when you find out what was wrong let us know.

[mikesim]

there turned out to be some instability using the crimping tool, some wires weren't connecting very well. i guess the VS3 is only meant for very thin wire guages. also the connector on the AFC was corroded and we just hard-wired it.

the major poblem turned out to be the CAS alignment pin being broken, and we weren't getting the right spark timing. it took awhile to get into the right position without it, but after she started up just fine.

SUPER rich though. anyone else using 450cc injectors and no FPR? the AFC is set to -22% for idle right now. can anyone share their AFC AFM adjustments starting from 800-3600 on low throttle? that would be great until i can get it to the dyno.

[c-rad]

The FPR has nothing to do with the injectors. The only way the FPR would be a problem is if the fuel pump you are using is overrunning it. If you are running a Walbro 255HP, then that is most definitely the case.

Your idle shouldn't be at -22%. Although the injectors are roughly 22% larger than stock, you have to compensate for the injector dead time. A good number for the 1k setting with 450s would be -10% to -12%.

And as far as your connectors are concerned... throw them in the trash and use a soldering iron. Its the only surefire way to go!

[float_6969]

My Walbro was over running my FRP. I had been having problems with unstable AFR's, but I wasn't sure that my readings were correct. After my short time at the dyno, his results agreed with mine. I know my fuel curve is smooth, the injectors are new, the fuel pump is new, the fuel filter is new, so the only thing left is the FPR. I just ordered it today and should have it friday. I'm hoping that will solve some of my cold start problems as well. (it always starts, but not quickly, and sometimes it dies.

[r34 gtr]

i had that same problem with the tach signal on my car when i rebuilt the engine. strange thing was that the safc2 was already hooked up and it never gave us a problem. it just sort of fixed itself and ive never had a problem since! my wires were all soldered too!

man, ive got my 510s running -15% at idle up to -12% at redline and about the same turbo. its probably why my car wont run by itself until its warmed up completely. im also using the walbro 255 overfuel-o-matic.

- tim

[mikesim]

-10 to 12 is pretty safe, but it tends to bog if i get on the throttle. should i do the same with the hi throttle afr's as well? just from 1-3K i'm thinking.

ya, i learned the hard way that soldering is the #1 surefire way.

float - i'm going to look into mine, my car likes to do erradic things on a cold start. some days it'll start fine, other days it'll take awhile, and it also dies once in awhile.

also, it seems to be boosting to about 9psi. is that out of the compressor range for my turbo (surge)? i wouldn't think it's too low since it's like an in between T25 and T28, but it's always good to ask.

[r34 gtr]

an hks gt2530 should be good for 18psi or so. its about the size of my gt28r and hks says itll push 320hp.

- tim

[float_6969]

What turbo is it? Regardless, if it's at least a T25, 9psi isn't too much.

[c-rad]

-10 to 12 is pretty safe, but it tends to bog if i get on the throttle. should i do the same with the hi throttle afr's as well? just from 1-3K i'm thinking.

Between 1-3k on the hi-thr settings, I would lean it out a good bit. The ECU has a natural tendency to pull timing hard at the onset of boost. I know when people do ECU retunes, they add timing in the that area. It gives a much better throttle response. Leaning out the SAFC will do the same thing since it will switch to a higher timing map with the less airflow. It's just pretty tough to get right with a SAFC since you are limited to just airflow correction and can't access the timing maps directly.

[mikesim]

What turbo is it? Regardless, if it's at least a T25, 9psi isn't too much.

actually i was wondering if it was too low, lol.

and thanks for all the help guys. i listened to u on the 12-13% and it doesn't hesitate anymore, and took 5% out on the hi throttle till 2800. i think this'll be the safest for now running 13* BTDC and 9 psi till i get it to the dyno.


Modified by mikesim at 9:20 PM 10/19/2005