help please big ci/ high compression breaking up *UPDATE*
I had an optima red top as well. I replaced it too.
I have an XSPower race battery now. But, I don't know if the red top was a cause or not.
I do know that when I installed a 16v battery and disconnected the alternator, I made two passes with no issues. I reinstalled my optima and hooked up the alternator and the problem came back. Put the 16v back in and the problem went away again.
I made 6 passes that night trying different things to diagnose the problem and the only one that worked was the 16v battery.
I hope you get it figured out quickly. Electrical gremlins can drive you crazy.
I have an XSPower race battery now. But, I don't know if the red top was a cause or not.
I do know that when I installed a 16v battery and disconnected the alternator, I made two passes with no issues. I reinstalled my optima and hooked up the alternator and the problem came back. Put the 16v back in and the problem went away again.
I made 6 passes that night trying different things to diagnose the problem and the only one that worked was the 16v battery.
I hope you get it figured out quickly. Electrical gremlins can drive you crazy.
I did. But what would happen with my car, was when it hit the cut off rpm, it would dump the hptuners datalog. So I couldn't see any specific changes.
It would get to 7000 rpm, and the engine would act like it hit a limiter, but shut off.
The data logger would shut off and come back on. The engine would come right back on, but all the gauges would act like I shut the key off and turned it back on. Full sweep of all the gauges.
Maybe try a different battery?
It would get to 7000 rpm, and the engine would act like it hit a limiter, but shut off.
The data logger would shut off and come back on. The engine would come right back on, but all the gauges would act like I shut the key off and turned it back on. Full sweep of all the gauges.
Maybe try a different battery?
Launching!
Joined: Mar 2011
Posts: 200
Likes: 0
From: wi
I did. But what would happen with my car, was when it hit the cut off rpm, it would dump the hptuners datalog. So I couldn't see any specific changes.
It would get to 7000 rpm, and the engine would act like it hit a limiter, but shut off.
The data logger would shut off and come back on. The engine would come right back on, but all the gauges would act like I shut the key off and turned it back on. Full sweep of all the gauges.
Maybe try a different battery?
It would get to 7000 rpm, and the engine would act like it hit a limiter, but shut off.
The data logger would shut off and come back on. The engine would come right back on, but all the gauges would act like I shut the key off and turned it back on. Full sweep of all the gauges.
Maybe try a different battery?
Last edited by my406cid; Dec 12, 2015 at 08:34 AM. Reason: Additional information
TECH Enthusiast
Joined: Nov 2006
Posts: 743
Likes: 4
From: melbourne (Aus)
What earths do you run?
I like to 2 big guage earths of opposite ends, so back of cyl head, then at front of engine
I'd go over entire loom from battery to engine as well. Idle car and jiggle connections
I like to 2 big guage earths of opposite ends, so back of cyl head, then at front of engine
I'd go over entire loom from battery to engine as well. Idle car and jiggle connections
The fact that it will free rev and not rev under load says your fuel injectors are huge pieces of ****, especially since your running them over rated pressure and close to duty cycle limitations. Get some quality stuff in there (FIC/ID 850 or 1000s) and try again. You're chasing ducks with all this other nonsense, when this should have told you everything you need to know (free revs, but breaks under load)
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11 Second Club
Joined: Mar 2012
Posts: 1,541
Likes: 15
From: South Florida
What's up man. Read your thread & watched the vid. If I had to guess I would also say fuel related.
Just for reference I had a problem with a intermittent break up/miss under load. After looking things over I also thought of the balancer as the culprit. Put a new ati unit on & no change. It actually turned out to be a broken valve spring. Keep on man. You'll figure it out.
Just for reference I had a problem with a intermittent break up/miss under load. After looking things over I also thought of the balancer as the culprit. Put a new ati unit on & no change. It actually turned out to be a broken valve spring. Keep on man. You'll figure it out.
It's fuel or electronics, so the easiest to figure out would be fuel with new injectors that you need even if the are not the cause. You can spend a year looking for electrical, so better to make sure that is the problem before you waist time even looking at it. Put bigger injectors on it.
Subscribed. I fail to see how a damper is going to fix a problem with it breaking up, but stranger things have happened. With a strong enough battery you should be able to make a pass or two with no alternator on the car at all. at It really sounds like a fuel delivery problem. Everything you've mentioned about it sounds like the system is marginal at best for the fuel volume you would need to support the horsepower and fuel you are trying to run.
Thread Starter
On The Tree
Joined: May 2008
Posts: 153
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If it was fuel related I would think it would show up on a data log or wideband? Injector duty cycle is right at 87% so high but not crazy. At gm fuel pressure the injectors are 72# per hour. I've changed pushrods, plugs, wires, coil packs, checked springs none were broken.. when I called ati they said the balancer definitely isn't sufficient. As for fuel I've debated on swapping to race gas to see if it changes anything.
Isn't sufficient for what? Even if it's 25% underdriven, at 7K the alternator is running what it would normally run @ 5250. It should be delivering plenty of current back to the battery. Where it goes from there needs to be considered though. Have you tried uploading your tune in to another PCM and swap it out? It would be highly unlikely that you have an intermittent component failure in the PCM but worth trying. 72 # per hour sounds marginal on E85 for a motor that big as is a -6 feed. Another thing it could be if you are running stock style high impedance injector is that the injector is locking up as you get very high up in the duty cycle range. The higher the fuel pressure the worse it gets too. Might need to look in to something like an Acceleronics box and low impedance injectors, or bigger injectors to get the duty cycle in check. If the injectors can't open, fuel pressure wouldn't drop, but it sure as hell won't run right either.
Thread Starter
On The Tree
Joined: May 2008
Posts: 153
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I'm not sure, from what I understand the larger the balancer the better it is at dampening harmonics. Current isn't the issue last data log showed 14v steady. I have thought about switching to race gas to drop duty cycle therefore I'm not leaning on the fuel system as hard and see what it does. I know there have been harmonics issues with other underdrive pulleys. With a large bore and high compression I can imagine it isn't do get the small balancer any favors. I just want the damn thing fixed lol. But yes we have swapped ecu problem is the same. Starts breaking up around 6200 or so.