O2 readings at idle Options

[yeahmag]

Just an idiot check here... I got Evan's old header on the car and all fixed up. It now clears my tuna can, has leak free collector/slip joints, mounts to the stock trans location, and has an O2 bung welded just past the collector.

Now my question is simple. I wanted to idiot check that I should be gunning for 12.5:1 or so at all points; idle, transition, at WOT. I leaned out on idle to the point that I think I'll need a 65 idle jet on my 40 Dell's (34mm vent). I took an extra full turn on the idle volume screws to get it around 13.5:1.

I must say though I picked up more than a few HP with it. It's a 4-1 in somewhat of a KH design with a Phase9 style muffler with an extra 360 degree SS loop between the collector and muffler to add some length to the secondaries.

Pictures coming...

[brant]

I'm not expert.. but in my opinion that would be fine
just make it transition well from stop lights and not bog too bad.

then use the innovate for load testing on the road

I used an innovate to jet my carb'd street car
I did a part throttle average
and a redline average
(you can also watch for anomolys... or weird numbers in between)

the redline is really the more important number. If you have to sacrifice your part throttle in order to not go lean at redline then that is the sacrifice to make. You can change emulsion tubes (or venturi's if you have too) to get your part throttle numbers back.

Redline should drive your jetting and work backwards from there

I also used an innovate to tune an MPS on a street car and it was much the same process.

I also use an innovate to tune my race car, and I could care less about anything below 4,000rpm... so its the same process with all of the attention given to the range of 4k - 7.5k

in my opinion... idle jets aren't about fuel ratio adjustments. They are a way to fine-tune the main jets and also to tweek your low throttle response.

brant