Issues staying running


New Member
Aug 29, 2013
Hello everyone,

A while back I had a set of cushman stage 2 NA cams installed with new chains and guides. I also have a dragon 75MM TB and trick flow plenum with a factory MAF and an aftermarket aluminum CAI. I also installed a plastic Ford Racing intake manifold. Fuel rails are automotive with custom lines, 6AN fittings and inline check valve. I am running a stock 2V lower end and a stock 2V heads with upgraded springs and retainers and SOHC.

Things have been swapped on and off fuel wise since we've been having issues. So its hard to isolate the issue.

The issue is that the engine cranks over, good, idles high around 2K, and will drop quick to nothing and turn off. if you feather the pedal, the engine rpms will drop to stable 750-1000 at idle. However, once its table at idle in park, as soon as the gear drops into R or D the motor will cut off fast without hesitation. If you build up RPMS and drop the auto trans into gear, it will go, and it will goooo.......

No engine codes, no misfires. It was been tuned with an SCT 4 and by 5 star, through email correspondence. We have been through 10 versions of tunes using the live link monitoring software. I have placed copper spark plugs in there (i think champion brand); could this be the issue? should I just run the factory platinum SP493s or use the iridium NGK TR55s for this and see if that makes a difference? Any ideas?

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10 Year Member
Sep 1, 2010
Kearney, NE
It is not the spark plugs. The $$$$ ones will last longer with EFI and a high energy spark, but copper core plugs are good spark makers.