Engine dieing when reved?

[MainMan857]

when I get on the track and the motor has a load on it around 7k revs it starts to die out and spudder but when I give it more gas it comes out of it mostly but not 100%. any ideas? fj1200 red box black coils new plugs

[IraceLegends77]

I'm guessing carbs. They will make you think it's electrical a lot of the time.

[MainMan857]

thanks. im getting them rebuilt/cleaned this week. see how it goes in 2 weeks. thanks. thought they needed to be cleaned anyway cant hurt

[phylzub02]

you say red box, and black coils??which coils??with the spade or a wire attached????There are 2 different ones????just curious...should use red coils too.3.0 ohm verses 1.8 ohm...just my thought..

[justfreaky]

you say red box, and black coils??which coils??with the spade or a wire attached????There are 2 different ones????just curious...should use red coils too.3.0 ohm verses 1.8 ohm...just my thought..

Randy posted this on coils not long ago:

You can use the 3.0ohm Dyna coils with the FJ rectangle black box, but not the XJ square black box.

Or you can use the FJ coils, with the Dyna box.

The FJ coils have pigtail wires coning out whereas the XJ coils have a male spade terminal sticking out for electrical connection.

Randy - RPM

Steve

[justfreaky]

Could this be related to your previous engine problem?
My trouble shooting guide suggests:
1) Check fuel system for obstruction
2) Check ignition system for a failed component, poor contact, or change in timing. Check electronic module.
3) Check compression.

Steve

[IraceLegends77]

Something for all of us to remember is that the fuel that we get out of the pump now is crap. It will eat your fuel (if your using rubber) up and send all the pieces right to your carbs. Also if you check your pickup tube in your fuel cell. We have had two go bad on our team. The pump fuel is killing these hoses internally and will make you pull your hair out.

[justfreaky]

+1

[VMS Motorsports]

Fuel cell foam and the lines will deteriorate. Could be as simple as an obstructed fuel filter.
A bad ground will also cause an issue similiar to this

[MainMan857]

not 100% sure the coils but there from another legend car running red box and his runs fine. did compression and that was fine also. I had red coils before but 1 was not firing all the time so switched to the black ones for now at least. new fuel filter and also new(ish) carbs. I replaced the set that was already on my car with a pair that was sitting for 4 years but ran when taken off car. did a quick clean job and ran them. tried to make a race that same day all this was happening. never tried my old carbs with the black coils so I wasn't 100% sure what it could have been. thanks for all the help getting carbs done sometime this week will post after when test on the track to make sure everything is 100% before next point race I am going to.

[IraceLegends77]

It is simple but check your plugs too. It is easy to over look the trees because of the forest sometimes...Trust me I know.....