MY Real Street 275 build
10-22-2014, 11:11 AM
#786
Haven't had a chance to take it to the track. Taking it tomorrow.
I have new plug wires from Firecore that are supposedly a much much higher resistance wire. Rick@Firecore tells me that this helps with keeping the energy from the spark event isolated better.
I have LS3/LS7 coils that I bought from a guy in Mooresville for a great price that I am going to try. We put the other water pump we had here on my car as well. Also going to tighten spark plug gap.
Going to try these things one at a time and see what happens.
I guess that's kind of in limbo right now. If I can't get this issue figured out I don't know if I'm even going to go. If we can't fix it tomorrow, and I get some more ideas or things to try I will bring it down there if they let me test. I will not be entering another race with a car that doesn't run right though.
I have new plug wires from Firecore that are supposedly a much much higher resistance wire. Rick@Firecore tells me that this helps with keeping the energy from the spark event isolated better.
I have LS3/LS7 coils that I bought from a guy in Mooresville for a great price that I am going to try. We put the other water pump we had here on my car as well. Also going to tighten spark plug gap.
Going to try these things one at a time and see what happens.
I guess that's kind of in limbo right now. If I can't get this issue figured out I don't know if I'm even going to go. If we can't fix it tomorrow, and I get some more ideas or things to try I will bring it down there if they let me test. I will not be entering another race with a car that doesn't run right though.
10-29-2014, 01:23 PM
#787
Issue is still there. Tried new Firecore heavier duty Marine wires, tighter .018 plug gap, LS3/LS7 coils and new water pump. Nothing helped.
Went a new PB in the cool Friday night air. 5.33@136.5 with a 1.31 60'.
Got a handle on this boost controller now and how to bring the power in on a good track. Went 1.22 60' on Saturday morning, but car cut off about 200' down track at the end of a power wheelie.
Here is the 1.22 60' video:
Went a new PB in the cool Friday night air. 5.33@136.5 with a 1.31 60'.
Got a handle on this boost controller now and how to bring the power in on a good track. Went 1.22 60' on Saturday morning, but car cut off about 200' down track at the end of a power wheelie.
Here is the 1.22 60' video:
11-01-2014, 12:59 AM
#790
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Just found this build thread Martin. Looks awesome. I wish I knew enough (anything) about the FAST system to help you out with the shutting off issue. Are you sure it is not the reluctor wheel and sensor losing signal?
11-01-2014, 01:05 AM
#791
TECH Enthusiast
Do you know what Brian Black runs? I think he has good luck with them. Also, I read an article about a Duttweiler 2200HP SBC in a land speed car, and it ran coils. I know they were MSD, but thats about it. I'll see if I can dig up the info.
11-01-2014, 05:04 PM
#792
I was going to post the same thing. I just had a car with BS3 that had a break in the crank signal wire inside the wire coating. From the outside you could not tell the wire had a break in it but soon as you pulled on the wire it broke in two. It took a very experienced mechanic several hours with an oscilloscope to find it. Super odd electrical problems can be very aggravating and hard to find sometimes.
11-01-2014, 11:59 PM
#794
We worked on it all day again. We took a light and a mirror today after pulling the crank sensor out and turned the motor over by hand while examining the reluctor wheel. Turned the motor over at least 3 times and couldn't see anything wrong with the reluctor. We've torn down and re-built several motors that had known reluctor wheel issues so we at least knew what to look for when examining it. Of course it's not as good as pulling the motor out and taking a look at it, but nonetheless we did that.
Also checked the thrust on the crank and it feels solid with no excess play.
The car will now not even run more than 5-10 seconds at idle before it shuts off completely and not like it does when I'm making a pass. When I'm making a pass I do not have to restart the engine after it "shuts off". When it shuts off at idle it actually cuts completely off and I have to restart the engine.
If you grab the main wiring harness and pull it as far as the length of the wires physically allows away from the engine the car will run interrupted. The kicker is if you lower the harness back towards the engine after holding it up to allow it to run, it immediately shuts off.
We messed with multiple other things for hours trying to see if anything would allow it to run and nothing other than holding the harness further from the engine worked.
It now has LS3/LS7 coils on it, but it will still shut off with the LS1/LS6 coils so I doubt it's the new coils causing the issue.
The car was also driving left on the last three passes I made at Mooresville when I started to really put some power to it early finally. So I made some adjustments to the suspension in the rear end to hopefully help that.
Also checked the thrust on the crank and it feels solid with no excess play.
The car will now not even run more than 5-10 seconds at idle before it shuts off completely and not like it does when I'm making a pass. When I'm making a pass I do not have to restart the engine after it "shuts off". When it shuts off at idle it actually cuts completely off and I have to restart the engine.
If you grab the main wiring harness and pull it as far as the length of the wires physically allows away from the engine the car will run interrupted. The kicker is if you lower the harness back towards the engine after holding it up to allow it to run, it immediately shuts off.
We messed with multiple other things for hours trying to see if anything would allow it to run and nothing other than holding the harness further from the engine worked.
It now has LS3/LS7 coils on it, but it will still shut off with the LS1/LS6 coils so I doubt it's the new coils causing the issue.
The car was also driving left on the last three passes I made at Mooresville when I started to really put some power to it early finally. So I made some adjustments to the suspension in the rear end to hopefully help that.
11-03-2014, 06:48 AM
#796
Was actually thinking of a bad crimp or bad solder joint. If you have bullhead connectors one wire could be not snapped in all the way. Can make a connection and lose it then arc and have some feedback CPU goes nutty. Done everything else mite as remove the harness and take a gander.
11-03-2014, 10:18 AM
#797
I doubt it's a broken wire or a bad crimp as the car has run just fine with the harness in it's "relaxed state".
This is a noise interference issue through and through and I am not the first to have this issue with FAST XFI.
We are currently trying to decide what to do. Whether to tear the harness apart and completely re-wire it so that the wires we think are being interfered with are as far from the ignition as possible. Or to give up and try another EFI system.
The latter decision will cost me a good bit of change unless I can sell the XFI for a decent amount.
This is a noise interference issue through and through and I am not the first to have this issue with FAST XFI.
We are currently trying to decide what to do. Whether to tear the harness apart and completely re-wire it so that the wires we think are being interfered with are as far from the ignition as possible. Or to give up and try another EFI system.
The latter decision will cost me a good bit of change unless I can sell the XFI for a decent amount.
11-03-2014, 11:36 AM
#799
I've had my share of issue's with the FAST computers. Always an excuse and a ton of time finding issue's.
For coils,plugs,wires. I've been running ls7 coils, GM wires and tr8 plugs gapped at .030 for the last 2 years. Never ignition problems up to 7600rpm.
Still running a stock computer, little scared to swap it out and have electrical/tuning issue's when I have zero now.
For coils,plugs,wires. I've been running ls7 coils, GM wires and tr8 plugs gapped at .030 for the last 2 years. Never ignition problems up to 7600rpm.
Still running a stock computer, little scared to swap it out and have electrical/tuning issue's when I have zero now.
