[Tuske427]

Just sharing some pics and a quick story of a modest upgrade I made on my '69 GTO recently. I bought a new-to-me/ virtually new Sniper Stealth system here on the forums last spring, and it sat in a box for a while until I had a chance to install it.

One thing that I didn't plan for was replacing the intake. I wasn't planning on swapping this, but once I realized my FI wasn't a spread bore layout that became a necessity. My engine is stock so I opted for the Edelbrock performer due to it being readily available. I ground down the divider some on the intake to help open it up as I understand these FI units work better with an open plenum design. Using this intake I had to trim the AC bracket down to fit.

I also modified the original throttle cable to work on this. I had a leftover threaded Lokar adjustment sleeve and was able to add this to the original cable by cutting off the end, drilling the tube portion out and using some aluminum brazing rod to melt the cable back inside. Seems to work well.

I also replaced the tank with the Tanks, inc. unit with internal baffles and installed that, as well as an adjustable regulator in back, and bent a new metal line up front

After getting everything assembled I had to upgrade the software in both the controller and the FI unit itself to be able to add the basic tune, and then I was able to start the car. It ran OK but the self tuning feature didn't seem to work too well. I'd get popping, back firing, adn the air/fuel ratio would go from 9 .55 to 35.99 and back n forth. When I got it tuned they told me the O2 sensor was bad, despite it being new. They disabled it in the tune so I don't even need to replace it now. I suppose if I ever modify the engine I'll need to go back to them for a retune, but for now it's working well.

If you add a system like this getting a proper tune is a must. I would recommend one in person where they can adjust on site either by driving or by using a dyno. I've had a few aftermarket FI systems now and in every instance it's a night and day better running car after being properly tuned.

I do notice an improvement in overall drivability, and better fuel economy, too. TBH my carb cold started OK, and the engine ran OK even when cold, but it had a terrible delay in the mid range throttle or when trying to open the secondaries and just made driving the car not nearly as much fun as it should be.

Hopefully these pics and story will be of help for anyone considering this.

[Tuske427]

more pics of the install and the tuning. there's a base tune pic that the air/ fuel ratio (red dotted line) is up/ down like a sign wave. not good. the car would surge and as mentioned ran poorly. afterwards it's much better all around.