So my buddy Brian with the Camaro calls up and we start discussing why the changes he made to his ride resulted in actually going slower.
Lots of advice from lots of people, and he is trying to sort out the conflicting and varied opinions. Change jets, add timing, read plugs, etc, with no specifics other than "that worked for me" kind of stuff.
He knows I like to science stuff out, and make changes methodically and slowly. And I do a lot of tuning on Weber 40-44-48 IDA carbs, with fairly good results.
I readily admit I know next to nothing about Holleys, other than basic carb theory that crosses over.
And I mention something along the lines of "why don't you weld a bung in your exhaust so we can stick my LC-1 on and see what is REALLY going on?"
I don't trust reading plugs (other than with a Loupe to check for detonation) especially with todays gas. Just too vague.
So he drops by with said bung installed, I shove the sandrail to the storage bay of the barn, load up the CJ7 drivetrain on the trailer, and we go to work.
Install went well on the LC-1. Had to do the free-air sensor calibration twice as that big weather-pack style connection was not plugged in all the way due to a bent connector, but otherwise things were good.
And showed a reading of 10-11 throughout the whole range, idle all the way to WOT under load. Way way rich.........and this was with plugs that showed lean. Yeah, I really don't do the "read plugs" thing.
His carb was pretty cool to start learning on. Neat stuff.
Called Milner351 for a point in the right direction and a kick in the pants......John steered us towards the idle screws on the metering blocks.
Just like he said, they were out way too far. Running them to 3/4 turn out got us in the 13-14 range from idle to mid-range, WOT is still doing something wacky, but the WOT mixture seems rich at first then gets better to end up at 11-12.
Going to change the power valve to a 3.5 next, and see what that change does.
Thanks for the pointers John!
Lots of advice from lots of people, and he is trying to sort out the conflicting and varied opinions. Change jets, add timing, read plugs, etc, with no specifics other than "that worked for me" kind of stuff.
He knows I like to science stuff out, and make changes methodically and slowly. And I do a lot of tuning on Weber 40-44-48 IDA carbs, with fairly good results.
I readily admit I know next to nothing about Holleys, other than basic carb theory that crosses over.
And I mention something along the lines of "why don't you weld a bung in your exhaust so we can stick my LC-1 on and see what is REALLY going on?"
I don't trust reading plugs (other than with a Loupe to check for detonation) especially with todays gas. Just too vague.
So he drops by with said bung installed, I shove the sandrail to the storage bay of the barn, load up the CJ7 drivetrain on the trailer, and we go to work.
Install went well on the LC-1. Had to do the free-air sensor calibration twice as that big weather-pack style connection was not plugged in all the way due to a bent connector, but otherwise things were good.
And showed a reading of 10-11 throughout the whole range, idle all the way to WOT under load. Way way rich.........and this was with plugs that showed lean. Yeah, I really don't do the "read plugs" thing.
His carb was pretty cool to start learning on. Neat stuff.
Called Milner351 for a point in the right direction and a kick in the pants......John steered us towards the idle screws on the metering blocks.
Just like he said, they were out way too far. Running them to 3/4 turn out got us in the 13-14 range from idle to mid-range, WOT is still doing something wacky, but the WOT mixture seems rich at first then gets better to end up at 11-12.
Going to change the power valve to a 3.5 next, and see what that change does.
Thanks for the pointers John!
Comment