For the stock ECU traction control isn't tunable. It's whatever the factory set it to.
If you want tunable you need to go stand alone. Once you have that the skies the limit pretty much.
Can't compare the old push rod engines to these. Have to remember there's a lot more going on in these engine. VVT, timing chain tensioners, whole bunch of lash adjusters and followers. His oil pressure is normal for the newer engines.
Personally I'd switch to an electric. Having a line split...
IMO if the car has forced induction a wideband should be installed.
Are you running cats? If not the exhaust smell is normal. If you are the tune is way rich.
Stand alones aren't necessarily made for the engine. It's a one size fits all kind of thing. So you'd have to wire it in. Although some of the systems are plug and play so they can use the stock wiring and dash.
I would start with the simple stuff. Don't run the nitrous and injectors until you have a handle on the current set up. You also learn a lot about your car.
My guess is you're in new territory here. I can't say I've heard of this area being a rust issue. But then I don't normally have to deal with rust where I live.
What kind of shape are the mounts in? Almost sounds like something torques over in deceleration and touches then has clearance when you press the gas and torques the other way.
I'd also check the u-joints and CV joints really well. I had a weird vibration suddenly show up and only at certain...
Why can't a car that makes over 700hp get good mpg? Its not making 700hp when cruising down the freeway. It's basically an N/A engine at that point. If a car is only getting 14mpg at that point its time to find a new tuner.
My old Cobra managed about 18ish on the freeway at 75. That one was...