Just ordered the kit tonight, and I was wondering if I could weld the stainless exhaust bung with my fluxcore welder (lincoln).
I have never weld stainless on steel.

Also what would be a good A/f at WOT?

 

11.5 on a boosted car.

 

Hell we took regular mild steel pipe, cut out a hole with the plasma cutter (do it with a drill press, it's cleaner), then took the MIG with regular carbon steel wire and welded it in with no problem. Did that on saturday, no problems, no leaks
issuez

 

I have my motor tuned to 11.8-12.0 A/F with the LM-1 on the street. 11.5 seemed a bit rich.
When I tune other's cars I go with 11.5 on a dyno & 11.8 on the street.

 

11.8 is ideal but really doesn't leave much room for error as far as variation in running temps, fuel quality, heat soak, etc.
issuez

 

Yes, and not only that, but 12.0 is really pushing it. I would never tune a car with boost for 12.0, that's kinda nutty.

 

When it was tuned on a dynojet248'for 11.5 it would puff brown (yes brown) smoke out of the tailpipes. I later discovered that 11.5 on the dyno made for low-mid 13's on the street! Every time to track on pump gas the motor blew a HG.

The way it's currently tuned (on the street at 11.8) there is no smoke of any kind out of the tailpipes & the car runs flawlessly at the track or on the street. I've only heard detonation from too much timing. It's backed off to a safe 17 at peak TQ & 20 at peak HP. The motor shows no signs of running 'too lean' with this tune. At 11.5 it ran fat...you could feel it & smell it out of the exhaust.

Actually, once I had finished my new exhaust (dumps) I datalogged a street pass & found the A/F to have jumped from my old tune of 11.8 to 12.1-12.3 across the board. Again, no signs of running lean, but I richened it up to 11.8 anyway. I ran it for a few weeks like that (in the low 12's) before I decided I'd better hook up the wideband just to make sure. The motor shows no signs of running dangerously lean.

From my experience (& what I've heard from professional tuners) everybody tunes the A/F on boosted cars to 11.5 on a dynojet248. On the street, as load values change, this typically results in an A/F of 11.8, which is suppose to be ideal for power & a safe tune on a boosted motor. Actually, what I've heard is that the most power comes from an A/F of 12.0.....which is probably why the new PMS comes dialed in to produce an A/F of 12.0 instead of the 12.8 (for N/A motors) it used to be setup for.

A/F is VERY important, but timing is the real killer.