WOT Surge Issue Please HELP
Thread Starter
Teching In
Joined: Jul 2013
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WOT Surge Issue Please HELP Hello members. Please help if you can. I am kind of getting frustrated sending my car to tuners and still have issues. So I will say I have a LS7 swap in an RX-7. I took my car to two tuners and seems like it pulls well on the dyno but when I drive the vehicle at home i get a surging problem in the engine at WOT around higher power band only. it just so happens the tuner I trust is about two hours away and can't just take it over for him to do data logging due to his schedule. I know this is not too detailed for the smart people here but any advice on troubleshooting would help. I am totally pissed i cannot drive my car properly and have no where else to turn to right now. Thanks folks please let me know...
V/R
Greg Olson
V/R
Greg Olson
Hello members. Please help if you can. I am kind of getting frustrated sending my car to tuners and still have issues. So I will say I have a LS7 swap in an RX-7. I took my car to two tuners and seems like it pulls well on the dyno but when I drive the vehicle at home i get a surging problem in the engine at WOT around higher power band only. it just so happens the tuner I trust is about two hours away and can't just take it over for him to do data logging due to his schedule. I know this is not too detailed for the smart people here but any advice on troubleshooting would help. I am totally pissed i cannot drive my car properly and have no where else to turn to right now. Thanks folks please let me know...
V/R
Greg Olson
V/R
Greg Olson
could be a few things.
fuel comes to mind. Pick up being exposed. Also fuel consumption under load while driving can be different than that on a dyno.
share more details on what it is doing.
DBC or DBW?
could it be picking up some knock ?
Thread Starter
Teching In
Joined: Jul 2013
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any way to log it while driving?
could be a few things.
fuel comes to mind. Pick up being exposed. Also fuel consumption under load while driving can be different than that on a dyno.
share more details on what it is doing.
DBC or DBW?
could it be picking up some knock ?
could be a few things.
fuel comes to mind. Pick up being exposed. Also fuel consumption under load while driving can be different than that on a dyno.
share more details on what it is doing.
DBC or DBW?
could it be picking up some knock ?
Only logging software i have is ToadScan. Would that work?
What you really want to see is AFR with a wideband O2 meter.
Dyno obviously is stationary. And a dyno pull is relatively short duration.
The road is totally different.
What does the fuel system consist of?
Dyno obviously is stationary. And a dyno pull is relatively short duration.
The road is totally different.
What does the fuel system consist of?
Thread Starter
Teching In
Joined: Jul 2013
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I have a close neghbor getting HPtuners in a few days to log data. My fuel system is a Walbro 450 pump and constant fuel pressure at 60psi with 93 octane. No lag in pressure when WOT either. I was going to replace the fuel filter just to be safe but if the pressure is constant i see no reason the filter is clogged or dirty. I might replace the plugs but will that be necessary?
I have a close neghbor getting HPtuners in a few days to log data. My fuel system is a Walbro 450 pump and constant fuel pressure at 60psi with 93 octane. No lag in pressure when WOT either. I was going to replace the fuel filter just to be safe but if the pressure is constant i see no reason the filter is clogged or dirty. I might replace the plugs but will that be necessary?
A gauge isn't sensitive enough to show the story, because of latiency.
Thread Starter
Teching In
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Curious how you know there is no lag in pressure or volume when you're not data logging it? Is the tank say, at least 1/2 full or more? If I have just a tad under a half tank, I can get my truck to get a lean spike on a hard pull when the fuel sloshes.
A gauge isn't sensitive enough to show the story, because of latiency.
A gauge isn't sensitive enough to show the story, because of latiency.
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Thread Starter
Teching In
Joined: Jul 2013
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Hello everyone. It has been a while but I like to give an update and provide some additional data. It was recommended from a few folks to install a surge tank and increase the fuel line size. Well I did that and put two surge pumps with plenty of volume. The hesitation was still present and I am at a lost of what to troubleshoot. I don't want to keep sinking money in this as anyone would understand. So, a friend of mine recorded three runs on HP tuners with the hesitation. Could some of you folks please look at these data logs and try to help me out? If I don't get it resolved soon, I will most likely sell the car...At least that is how frustrated i am.
Thread Starter
Teching In
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What kind of dyno do they have? Does it have a load cell? We take cars straight off the dyno and run through through 1/4 mile and also through the mile but our dyno has a load cell. If there dyno is inertia only then your only option is on the street or a track.
Thread Starter
Teching In
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Understood but what would be the difference data logging using a dyno under load and driving the vehicle? Do I need to data log something different?
Thread Starter
Teching In
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Listen to what people are telling you.