Carbureted LSX forum - MSD 6010 wont rev passed 2200rpm

Just got my turbo lm7 fired up and it runs great at idle. But once i rev it it starts misfire and limits its its rpm to around 2200 but the limiter isnt hooked up. I pulled each coil they are working changed plugs, changed carb, fuel pressures good, hooked up laptop everythings looks fine.

Video uploaded, http://www.youtube.com/watch?v=PEUQIsAylYQ

that really sounds like a limiter of some sort. going thru the basics, the high limiter isnt set to 2200 in the msd box is it? also is the low limiter (2 step) set to anything and the switch is on or somehow activating? plug your laptop in and see what the timing and stuff is doing while its doing it. thats a nice feature for this nifty little box i thought. im running a 6010 aswell and this really sounds like a limiter and not a missfire more like something electronically controlled...

I tryed running on one of the chips then i removed the chip,
adjusted with the laptop , same result.

How do you know it is the ignition and not a lack of fuel

Used tryed two carbs my 650 then my 850 of my big block exact same result.

And the wideband is showing around 12.5:1 afr
.

Where are the limiters on the box set?

Low is set at 3k and high is 6.5k, I think the 5.3 might be trying to save it self, cause im starting of with 13 lbs of boost with the 88mm and 100 shot to spool it. Its hard to tune when it wont go above 2k.

Hard? You mean impossible. Os boost coming in for some reason that soon? I would imagine not with that size hair dryer. Make sure the low end limiter is not activated, watch the lap top, it should tell you, at 3000, the tach is not going to keep up some times and may only show 2200 or so.

do you maybe have the 2 step wire run to constant 12 volts?

Low rev limiter wire isnt hooked up, i looked at the tach on the computer screen 2200 rpm when it misses every time ,checked all the limiters normal and i saved everything to the controller, i contacted MSD hope they might be able to figure it out. I never seem to have any luck with electronics, i thought the valves might have been sticking open cause i put .025 longer pushrods for the ls6 cam. But it idles perfect and like i said 2200 rpm exact everytime and wont rev. passed that.

where do you have your msd box wired to. sounds like you have som volt drop over to msd power suplye.

Hmm never thought of that, voltage is coming from the old coil supply, when i used hei on my old engine i used a relay cause the coil supply was getting to hot i didnt think the controller took much amperage, i will have to try that.

Needs a constant minimum 12 v.

I will find another power tonight, but if there is somthing wrong with the controller i hope MSD warranty is good, cause i had the controller a year on the 28th of this month, I thought i was screwed cause i was reading a revised version of the instructions and the warranty disclaimer is about 3 sentences longer than the version i got with my controller and it states "This warranty is void for any products purchased through auction websites" I bought it new ,buy now, off ebay from a 100% feedback online store like i buy most of my stuff for security purposes. I went on msd site and went on their warranty page and it didnt say anything about auction websites.

Call them, tell them it has been sitting and you just installed it and would like them to check it out.

I don't think this has anything to do with it but you are running a Blow-Thru carb right?
What turbo you got??

Yes its blow thru ,running a 850 with annular boosters and BRPV ,aeromotive a1000 eliminator pump and a boost ref. regulator. Turbo is a majestic 88mm T6 .96 a/r comp., 1.00 turbine, home built log style manifolds 1.75" into 3". 2.5" into 4" hotside, 4" down pipe, 3" cold side, a2a intercooler, meth injection, nitrous. After i first started up it did the same as the video ,then i put a 650 and took the video, exact same result.

Well that sucks, it defiantly sounds like the limiters hitting. Maybe try it with the carb-hat off and see what happens.

Well guys messed around with it some tonight, put the controller power right to battery 12 volts started it up runs excellent, thanks for all the input to everyone, or i would still be scratching my head.:)

LOL, thats great man, usually they will not even start.

Glad to see you got it sorted out.

So you just needed a better power source. Easy fix

now lets see a video of it makin some boost:drive:

Power source or better ground, had same problem but at 6200rpm.

One issue is the ground wire is like tooth floss, its like 16 gauge wire. We had to ground it back to the power supply, all of a sudden 7000+ rpm no problem.

IF that is the problem.

Fraser

lsx74camaro, you've probably already made a permanent fix for your voltage drop issue but I will post this here anyway for future reference.

Whenever hooking up aftermarket ignitions or EFI systems, use the original coil 12v wire to trigger a relay to provide a strong constant 12+ volts direct from the battery. You won't have to worry about voltage drops or noise this way. Use 16 gauge wire minimum from the battery(positive and negative) to the relay and then to the ignition box.

All of the major retailers should include a simple relay diagram with their instructions and specify that they recommend you hookup directly to the battery through a relay. I am using the Edelbrock box, made by MSD, and it says nothing to this effect.