KiddEng

aiight i just got back from the tuner...it seems that im making good power up until 4.5k where it flattens out and starts dying on me...im making good torque but the hp just isn't there after 4.5k. The tuner said it might be the v-afc causeing problems after vtec kicks in even though i don't have the vtec wire connected. and that the S-afc would mostly solve the problem? i should be making atleast another 20-30hp at the top end..but its just not..boost stays constant up to redline and the fuel is steady at 12.0-12.5 throughout the rpm up until where power drops off...here are my graphs



would the s-afc help after this point? i dunno what else to think of...all hoses and lines were check and are ok.

stumped and pissed...

laters


[Modified by KiddEng, 3:46 PM 8/23/2002]

DIRep972

iTrader: (1)

are u detonating?

dustin

6k+ rpm looks really bad, misfire or detonation going on there

KiddEng

when we were doing the pulls i didn't hear any detonating...and the tuner didn't say that it was...but still, after 4.5k it seems that power is dropping off...the fuel curve is at 12.3-12.5 range but after 4.5k it seems to be richening up... can the FMU be dumping too much fuel even though we leaned it on the v-afc?

rjardy

it could be, what size disc are you using in your FMU and what size injectors are you running allso?

Rob

KiddEng

im running 12.1 fmu with 280cc injectors

that could be the problem u think? cause generally around that area is when full boost is reached...but doesn't the v-afc over rides it and lean its out? or doesn't matter casue fmu is boost dependent?

i really dont want to buy a s-afc if thats not really the problem..its what the tuner thinks it is....i think it isn't cause i disconnected the vtec control wire from the v-afc..so wouldn't it make it just like a S-afc?

DC2R714

Dude I have the same problem. I have a 12:1 FMU with 310 injectors. I have a dyno session all day next saturday. My graph looks the same but it was flat it didn't die like that. Let me know if you figure it out. Otherwise I will try to post next week. I think it is the FMU. Try disconnecting the VAFC and do a pull then try disconnecting the FMU and do a pull see if it gets better.


[Modified by DC2R714, 10:24 PM 8/23/2002]

DIRep972

iTrader: (1)

well if the Vafc is not installed correctly, it will definitly cause problems. I would try taking out the VAFC and see how it runs. that will tell u if the vafc is the problem. 280cc injectors and 12:1 FMU will definitly cause u to run rich, but i dont know about it causing u to run rich enough to cause ur dyno to look like that. also make sure all the settings on the Vafc are correct. my friends accidently got switched to 6cyl setting once and it made his car run CRAAAAAZZZZZZY wierd.

niedejb

I'm guessing its ignition (gap on plugs too big). I dont like the looks of the graph above 6K....somethings wrong.

Leave the VAFC wired as its supposed to be and figure out why your max torque is @ 3700rpm.

Wish I could be more help....


[Modified by niedejb, 4:30 PM 8/23/2002]

KiddEng

im thinking the 12:1 is too much even for 280cc injectors...
i don't have loot/access to a dyno all the time..this one session set me back 150..so let me know if u get ur problem fixed if its the fmu or not. how much do all day sessions cost anyway? thnks for all who replied..this is frustrating...

also my timing is at stock setting..runngin 6psi.

its gapped at .043 right now...it seems that i get max torque be4 i reach full boost cause at 4k is when full boost is reached.

im sure the vafc is hooked up correctly..minus the vtec controll wire. if that wire is connected again. it will cause me to get that revlimit problem that i was having the first time around.
can leaving that wire disconnected cause it to run worse at that rpm range?

the settings on the vafc is correct because we put everything back to default settings and then started to do pulls.

dustin

Gap your plugs to .030 and see if it feels better.

niedejb

IMO this is more of a problem than the VAFC wire. By disconnected do you mean the ecu is controlling vtec or your simply not using vtec?

dustin

Yes, verify that vtec is, in fact, engaging.

Dustin

DC2R714

I will let you know. The dyno I am going to charges $90/hr as long as you stay for atleast 6hrs. My tuner is paying for it because I was pissed about the power loss on the first dyno session that I payed for $238 . I think it might be an FMU problem. My timing is at 14degrees and we gapped the plugs at 32,30,28, and nothing. Thought it was my cam gears, switched them back to stock and nothing. Very frustrating but we'll get it.

KiddEng

i'll try to gap it a little smaller...and see if i can notice any diff at that rpm range.

yeah the vtec wire isn't connected meaning im letting hte ecu control when vtec kicks in. because the way vtec-e is setup..the ecu can engage vtec whenever it senses it needs more power..so i had times when i can feel the vtec kick in at 3k and normally its on at 3800...
DC2R714 - yeah cool man let me know how it turns out...

as of now the car is pulling stronger than how i used to have it..but im still worried about the top end after 4.5k...atleast i know its not running lean there...i just wnat to tap into the lost power...

thanks guys for all ur help!

DIRep972

iTrader: (1)

ur problem goes beyond running rich and overly gapped plugs. your making more peak torque then hp. from 6k-6.5k ur making only 90-80hp. u r lacking ALOT more then just 20-30hp in the top end. more like 70-80hp. something is seriously wrong w/ ur set up. and the only thing i see is that u have a vafc hooked up on a non vtec motor w/ a wire disconnected. for some reason that sounds to me like its ur problem. re-gap ur plugs and let the car run off the stock computer. then test drive it and see where u stand.

dustin

Was the v-afc ever controlling vtec?

Understand that when you install the v-afc, you cut the vtec signal wire. So if you just disconnected the wire from the v-afc, it will never engage.

Dustin

KiddEng

i remember the tuner telling me something about the vtec. i told him that i din't connect the vtec wire cause it'll cause the problem i had be4. he said that the point where its set at on the vafc, the vafc will adjust the fuel from the point on b/c its thinking that vtec will be on there so it jacks up the fuel there too...now would this hold tru even though im not using the vtec control from the v-afc? do see what im trying to get at?

but heres the twist: i asked him if it would work if we jacked the vtec point to 8k so that it won't even reach and dump fuel...but it still happend that fuel delivery is richend up after the 4.5k mark...

so would it be the afc or fmu to be dumping in fuel?

niedejb

The vafc only puts in the fuel you tell it. What settings are you using for your pulls?

senpai

I'm confused as to why you're not just connecting the VTEC wire. Why would it BEING connected cause you problems?

As I look in my VAFC manual, you're supposed to cut the VTEC wire in half and connect each side to their corresponding wires on the VAFC harness.

KiddEng

the reason i got the v-afc in the first place was because the motor is vtec-e , not regular vtec. the vtec signal wire yes it was cut..but its put back together i didn't leave it cut. the v-afc never controlled the vtec on the car..i think thats why i was having the revlimit problem earlier., but since i disconnected the vtec controll wires and reconnected together the ecu vtec signal wire. Yes vtec engages when its controlled by the ecu.

if i disconnect the vafc and just let ecu handle it..i think i would run crappier and real rich since most of my settings are leaned out.

here are the settings: WideTH: Lvt Hvt rpms 7k+
1k: -23 4K: -9 6.5k: -7
2K: -18 5K: -10 7k: -4
3K: -11 5.5K: -9
NarrowTh: Lvt Hvt rpms 7k+
1k: -4 4k: -9 6.5k: -12
2K: -6 5k: -10 7k: -12
3k: -8 5.5k: -11

V/T cont: L->H 5500
H ->l 5000 *during pulls we had this set here, and set at 7k

Throttle:
Lo = 10%
Hi = 50%

DIRep972

iTrader: (1)

so u do have a vtec motor but not a vtec ecu?


[Modified by DIRep972, 11:38 PM 8/23/2002]

KiddEng

the reason im not connecting the vtec wire is because initially it was connnected and i wasn't able to rev past 4k...it would hit a limiter/ fuel cut scenerio. I sourced it to the vtec controll wire which when i disconnected it...im able to rev past up to redline.

DIRep972

iTrader: (1)

damn. this is getting confusing now haha. ****.

KiddEng

d16y5 vtec-e HX motor HX ecu . figureing that since i have vtec i would be albe to use v-afc...but found out other wise...


[Modified by KiddEng, 6:42 PM 8/23/2002]