Sluggish pedal response.
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Sluggish pedal response.
My car has sluggish response when you punch the throttle. It's almost like it bogs for 1/2 a second or a full second and then goes. Also, the throttle response is not very linear at all. When you barely push the pedal, it's either not at all or a whole lot. I realize that when the throttle is barely pushed, it may be caused by some bind in the cable, but I have no ideas for the sluggish response. It's almost like fuel pressure dips for a fraction of a second. BTW, I"m in the process of installing a fuel pressure guage as we speak.
It's the same with the blower pullied or not pullied.
It's the same from idle or 1500 rpm with the pedal already slightly depressed. I thought it might be the cam, but even from higher rpm, it still does it. I'll give it a try from 2500 or 3000 rpm tommorrow to see if it does it there too.
The car pulls like mad, it's just the throttle response that stinks. Anyone have any ideas on what this could be?
Check my sig for more info....
It's the same with the blower pullied or not pullied.
It's the same from idle or 1500 rpm with the pedal already slightly depressed. I thought it might be the cam, but even from higher rpm, it still does it. I'll give it a try from 2500 or 3000 rpm tommorrow to see if it does it there too.
The car pulls like mad, it's just the throttle response that stinks. Anyone have any ideas on what this could be?
Check my sig for more info....
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 59
From: Fremont Oh
You maybe too rich on the low end (at idle)...
Once you get your gauge on you can prehaps try adjusting you FMU or drop you fuel pressure a bit depening on the injectors you have...
Are you running your water injection yet? If so it may be kicking in too soon...
Just a thought...
Mo
Once you get your gauge on you can prehaps try adjusting you FMU or drop you fuel pressure a bit depening on the injectors you have...
Are you running your water injection yet? If so it may be kicking in too soon...
Just a thought...
Mo
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Mo' I know that you are running mass air which recirculates air out of the bypass. Anyone who has speed density and big injectors out there, did you have any issues like this from the air venting to the atmosphere and a lack of air going to the engine because of the airflow traveling out of the bypass?
I've figure that it's actually not a dip in the fuel pressure, but rather the engine drastically richening and bogging down.
I think I'm going to try an adjustable fmu (allowing me to drop base fuel pressure) on the car to see if I can lean it out accross the board and then use the alky setup to start adding fuel back at 3psi.
I've figure that it's actually not a dip in the fuel pressure, but rather the engine drastically richening and bogging down.
I think I'm going to try an adjustable fmu (allowing me to drop base fuel pressure) on the car to see if I can lean it out accross the board and then use the alky setup to start adding fuel back at 3psi.
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 59
From: Fremont Oh
Is there a difference with the water injection?
I would get your idle cruise fuel issues resolved before getting into your high end... my gut feeling is your dumping too much fuel... what size injectors are you running?
Mo
I would get your idle cruise fuel issues resolved before getting into your high end... my gut feeling is your dumping too much fuel... what size injectors are you running?
Mo
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Melting Slicks
Joined: Mar 1999
Posts: 2,535
Likes: 2
From: Rochester NY
Originally Posted by bacardioil
if your running a stock computer, the computer will not read properly 38 injectors on 92 or 93 cars. injectors to big. go to 30s
Melting Slicks
Joined: Mar 1999
Posts: 2,535
Likes: 2
From: Rochester NY
Originally Posted by bacardioil
talk to greg at blower works
50s is the maximun the ecm can control. Some other use a impedence converter box to allow to use much larger low Z injector 72-96s injector. The only problem with these monster injector on the 92/93 cars are becuse they batch fires this mean they fired both banks at the same time and some it load up to much fuel and it hard to control. The reason 94-96 are fine because they are sequential that it fire each cylinder indiviually.
As far you cannot run 38s is a bogus. my car a 93 turbocharged 383LT1 and I am running 16 injectors and they are 50s each. Now you tell me, you can not run 38s?? to me you don't have a clue what ya talking about.
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
unless I get the duty cycle up on the 38's, I may drop down to 30's. I have the fmu still hooked up and so I'm only seeing about 69-70% at redline. I also need to up my redline, but that's a different story (it's only 5500 right now. I want 6000+)
I've also added alky injection, so I probably won't be using as much fuel onceI get everything dialed in on the dyno.
I've also added alky injection, so I probably won't be using as much fuel onceI get everything dialed in on the dyno.
Last edited by qwiketz; Aug 19, 2005 at 09:51 PM.
Supporting Vendor
Joined: Oct 2004
Posts: 761
Likes: 67
HI BRUCE, GREG HERE. IN DEFENSE OF GENE I MAY NOT HAVE EXPLAINED MY COMMENTS TO HIM FULLY. WHAT I MEANT TO SAY WAS THAT MUCH BIGGER THAN 30's ON A BATCH FIRED PCM AND YOU MAY NOT PASS A SNIFFER TEST, PARTICULARLY WITH A 650 RPM IDLE. THE TURN DOWN RATIO ON INJECTORS IS SUCH THAT THERE IS NO RESOLUTION BELOW ABOUT 1.2 ms. I'D BE CURIOUS TO KNOW IF YOU COULD PASS A SNIFFER TEST WITH 50's AND THE BATCH FIRED PCM? REGARDS GREG
Drifting
Joined: May 2003
Posts: 1,730
Likes: 1
From: Charlotte NC
St. Jude Donor '05
Originally Posted by BlowerWorks
HI BRUCE, GREG HERE. IN DEFENSE OF GENE I MAY NOT HAVE EXPLAINED MY COMMENTS TO HIM FULLY. WHAT I MEANT TO SAY WAS THAT MUCH BIGGER THAN 30's ON A BATCH FIRED PCM AND YOU MAY NOT PASS A SNIFFER TEST, PARTICULARLY WITH A 650 RPM IDLE. THE TURN DOWN RATIO ON INJECTORS IS SUCH THAT THERE IS NO RESOLUTION BELOW ABOUT 1.2 ms. I'D BE CURIOUS TO KNOW IF YOU COULD PASS A SNIFFER TEST WITH 50's AND THE BATCH FIRED PCM? REGARDS GREG
I've got 42's in my 93 and it can pass no problelm. idle with a 42 is about 1.7 ms.
Melting Slicks
Joined: Mar 1999
Posts: 2,535
Likes: 2
From: Rochester NY
Originally Posted by BlowerWorks
HI BRUCE, GREG HERE. IN DEFENSE OF GENE I MAY NOT HAVE EXPLAINED MY COMMENTS TO HIM FULLY. WHAT I MEANT TO SAY WAS THAT MUCH BIGGER THAN 30's ON A BATCH FIRED PCM AND YOU MAY NOT PASS A SNIFFER TEST, PARTICULARLY WITH A 650 RPM IDLE. THE TURN DOWN RATIO ON INJECTORS IS SUCH THAT THERE IS NO RESOLUTION BELOW ABOUT 1.2 ms. I'D BE CURIOUS TO KNOW IF YOU COULD PASS A SNIFFER TEST WITH 50's AND THE BATCH FIRED PCM? REGARDS GREG
I doublt my car will pass emission. I doublt any 1000hp car will pass emission. The 50s should not have any effect on the sniff test. I personally have met someone who I used to tuned my car in the pass year ago. His 8 rib setup, Vortech 12psi intercooled 355ci LT1, ZZ9 cam. The car is a 93LT1 dyno 570rwhp. He lives in the Maryland Annapolis. He did not having any problem passing emission there.
Greg, Either way. we are clear up now about the comments Gene made stating that the stock computer cannot use 38s injector. Thing COOL.
Bruce
Last edited by Bruce; Aug 20, 2005 at 11:45 AM.
