"Rev Limiter" feeling @ ~2500 RPM w/ Blower Installed

criticman

Member
Sep 7, 2003
723
1
16
Rome, GA
I installed my Paxton Novi 1000 supercharger last weekend and after hunting down some oil leaks, got it running. I am posting the problem here because I think the problem has to do with a non-blower specific part - that and no one seems to care in the supercharger forums here.

Present setup (key items):
-Stock MAF
-Paxton Novi 1000 (new, 2 belt setup)
-Accufab 70mm TB
-FRPP Cobra Intake Manifold
-Stock Heads
-Stock Bottom End
-Crane Hi-6 Ignition
-MSD Blaster TFI Coil
-Jeg's Spiral Core Plug Wires
-Autolite 24's gapped to 0.040
-Paxton FMU for the stock 19# injectors
-Stock Fuel Pump
-Anderson Ford Motorsports PMS
-Base timing at 10*

The problem:
When the throttle is over 50%, in any gear, the car hits a "wall" around 2500-3000 RPM (according to the stock tach). Best I can describe, it feels like hitting a rev limiter - it just cuts out, interior lights (including dash/gauges) flicker. Letting off the gas and pushing in the clutch brings it back to life, so the car does not completely die when this happens. I am able to part throttle go until about 3500 RPM without problem (it may go higher, but I am not going to push it in case this problem could be doing some damage).

Troubleshooting I have done:
- The problem first happened before I installed the Crane Hi-6. So, I installed it hoping maybe (as some people on forums suggested) that I was experiencing spark blowout since the gap is on the high side for boost with the stock ignition. The problems remains and is completely unchanged with the ignition installed.
- I turned off the PMS control to see if it was causing the problems since I had standalone mode kicking on at 2500 RPM. The problem remained.
- With standalone mode on with the PMS, I pulled timing out slowly as the RPM's increased but the issue remained.

Things I want to try:
- I am waiting on the new Pro-M company to hurry up and get caught up with my order I placed a month ago to install the 80mm MAF. I have 42# injectors waiting to go on that match the new MAF's calibration. I will remove the FMU once the new MAF and injectors go in.
- I have a Kirban adjustable fuel pressure regulator and fuel pressure gauge to install. Although I do not think it will help, I planned on installing it when I did the injectors.
- I have a 255lph high pressure Walbro fuel pump waiting to go in. I have not had time to put this in. Part of me thinks that with the new pump it could correct a lean fuel problem that may be happening even though this kit is supposed to run fine with the stock pump.

So, does anyone think my ideas above will help or do you have any other things that I should try to get this running? Last week was hell and I now have less than one week to get this running for a dyno session at my college's car show on Saturday April 1.

Thanks in advance for any input on this problem.
 
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The ground idea makes sense - a friend of mine suggested that as well. He also said to remove any corrosion from the battery terminals. I did upgrade my alternator JUST before the blower install, but I also definately got on it without any issues after the alternator was installed (130amp PA-Perf.) plus I also upgraded the power wire.

What grounds need to be checked and how does one check them?

So that's one idea...anyone have more? Or any thoughts on whether or not aleborjas' idea will fix it?
 
Did you check the range of voltage on your TPS. Mabey the sensor is going bad and only showing up at have throttle. Also find another stock MAF to put on just to see if the problem persists. I think alot of people hold on to the stock parts when they upgrade. I know I do for trouble shooting issues.
 
just4bob50 said:
Did you check the range of voltage on your TPS. Mabey the sensor is going bad and only showing up at have throttle. Also find another stock MAF to put on just to see if the problem persists. I think alot of people hold on to the stock parts when they upgrade. I know I do for trouble shooting issues.

I do not know about the range...but I do know that it read properly when setting it up with the PMS.

Since the Pro-M MAF will have new electronics, I am hoping it would fix issues if they are being caused by the stock MAF.
 
Spark blow out will not cause all the lights to dim, you have issues other places.

Go over everything you touched or removed during the install. Check all grounds although that still doesn't right as far as it shutting off. Install the Fuel Pump you are playing with fire, you may be running out of fuel...the 88lph just will not keep up with the large injector.

Got my Professional Mass Air meters in days...where did you order from?

If the tps voltage is good on the PMS then you should be fine. Did they give you a start up program?
 
Does it idle okay or is there a miss? Getting a PRO-M for a blower application made a huge difference in my car. Ran much smoother and got rid of the check engine light.

I would pull the plugs and look at them, as well as, gap them to .035.

Where is the ignition box grounded? It is very important that they have a good ground to function properly.

Can you hook up a FP guage and monitor the system while driving? I wouldn't put that thing on a dyno w/ a stock pump!!

Make sure you have the vacuum line on the FMU hooked to the correct port on the tree and also make sure you don't have the lines mixed up.
 
I'll try to reply to all...for some reason I did not get a notice of replies from the boards...odd...anyway...

  • The lights may not be dimming, could be me flinching from the sudden dive.
  • I will regap the plugs down the 0.035 from the present 0.040.
  • The voltage is correct in the PMS for the TPS.
  • I did not get a PMS base tune...I ordered it from a reseller for less several months ago. I planned on getting a base tune from StangTuning.com once the new MAF goes on.
  • Yeah, I know I need to get the fuel pump in ASAP...if I can't before the dyno event, I will not run it.
  • I also need to get the wideband bung welded on so I can get that up and running.
  • I ordered the MAF from JDsPerformance.com. Dave keeps giving me a song and dance about something with the mold manufacturer for Pro-M starting to suck, so they fired them and are with a new company now but the transition delayed delivery. If anyone knows this to be false, let me know ASAP so I can get this taken care of. I need the MAF ASAP!
  • One thing I found odd was that the supercharger kit had me cap off the vent tube line from the oil fill tube where it connected to the throttle body and had me run a line to a filter to another line into the little shield that goes over the filter. To me, this seems like it could be causing a vacuum leak?
  • The ignition is grounded to the chassis. Since the issue happened before the ignition install, I am not worried about it being the issue.
  • The FMU called for me to T into the the line that runs to the stock fuel pressure regulator...so that is what I did.
 
Im pretty sure all emmisions legal charger kit have the by pass tube from the oil fill rerouted to the same point in the system. That will not cause a vacume leak. It is basically the same as running it to your TB when it was (NA). The air moving past the port at the filter or TB will create a suction and it helps control pressure in the crank case. That is what a ford mechanic told me when I was complaining about having to run the tube to pass emmisions inspection.
 
Hmm. I wonder why it runs there instead of to the throttle body? And what do you do with that when you run an AFM or UPR fenderwell pipe instead of the little box cover the kit uses - where does the tubing run to?
 
I know Dave he usually a honest guy I wouldn't doubt it...

As far as the cap on the TB inlet that is correct, it will pull oil out of the valve cover under boost if connected. When you run a power pipe you can do other things...

My advice is to keep as many vac lines to there own source as possible, if not your competing for the same vac. I run the FMU, and Boost gauge to seperate ports. I prefer to drill and tap the boost line into the manifold, you can run the FMU line over to the sparre port on the tree. Keep the Fuel Pressure reg on the stock location, if you have a bypass valve put that on another source as well.

Welcome to the World Of Boost...
 
That is what I had heard about Dave...so I am hoping that Pro-M gets their act together quickly.

As far as "doing other things" when running a power pipe...what would those be? Because I have the pipe sitting on my kitchen table waiting for the Pro-M MAF to arrive.

Hmm, that may be good to do. I will try running the FMU vac line to the tree and see if that helps things. Of course when the MAF arrives I plan on ditching the FMU in favor of the 42# injectors I ordered from you along with a kirban regulator. But since the MAF is not here and may not make it in time for the dyno (especially not in time to get everything else in working order), I'll do my best to get it running with the FMU.
 
what I eventually had to do was drill a small hole for a fitting the the air tube would connect to. It is not pictured here, but is between the bypass valve and the 4" inlet tube on the upper right portion of the bung for the bypass valve.

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I would have to say the the term pull oil may be miss-leading as I have never really seen any oil in the tube except from what could have been from mist. You are correct that the same princible applies and it seems to work well. I can run the car with the stock oil fill cap on and it vents well. Before that I was running a breather cap and that is why they wouldnt pass it for emmisions.