Working in the heat!

[jdbubb at verizon.net (Dan Bubb)]

Spent Saturday replacing the tie rod ends and aligning my Audi A4. The original tie rod ends, amazingly, have a rubber sleeve in the middle that lets them stretch and contract a small amount, I guess to absorb road shocks, but now with the new solid parts, the car seems a lot less wandery. That was definitely a worthwhile project.

Sunday my nephew came over and for some reason all else stops when he shows up. Might have something to do with him owning the only turbo Scirocco in the family! :^(
When last dynoed the car had made 208lb-ft @ 3900 where the boost was spiking to 13 psi and 177 whp @ 5400 with boost at 10psi. Basically the torque just drops off in a straight line and we've been wondering where the restriction is that's causing the loss of top end. Mike's been slowly improving his Megasquirt maps based on datalogs and by leaning out the top end to match the lower VE up there to get a consistent AFR and playing with the advance he's been picking up a couple HP here and there (or so our butt dynos suspect!)

Anyway his car sounded really bad with an exhaust leak that coincidentally seemed to have improved the top end performance of his car? A quick inspection revealed the downpipe was cracked. Turns out it was nearly broken off at the turbo flange and also had a series of little separate cracks in the same area! Well, I don't feel too bad since this was the first downpipe I'd ever made, probably the one I learned to weld stainless steel on, it is totally unbraced and had lasted over 4 years! A little clean up and some bead blasting to remove any carbon in the area so it didn't contaminate the weld and I welded it all up as good as new although it did look a little like a Frankenstein downpipe with all the little weld beads running this way and that.
While I was welding that up Mike was playing around with throttle bodies and found out that the bigger A2 TB would mate up sufficiently well to the IC pipe that was shaped to match the small TB. So, we changed that out while we were at it. Recall that he's using MAP based accel enrichment so we're just using regular TB's without TPS, so that was an easy swap. Mike took the car for a test drive and his butt dyno indicated the top had picked up yet more power despite us welding up the power inducing exhaust leak. ;^)

The last change was an effort to kill two birds with one stone. I had welded a tail pipe and hanger to a 2.5" Borla muffler I had laying  around for my 16V to replace the Flowmaster that sounded like ass. Well, turns out the Borla didn't sound too good either and was too loud for my tastes. I figured we'd swap the Dynomax on my nephew's car for the cobbled up Borla on my 16V. Pulling the Borla off the 16V wasn't too bad since I'd been careful to not tighten the clamp too much. Pulling the Dynomax off my nephew's car was even easier since it was an old old muffler and I just torched it off! ;^) 
Well, that's when I discovered that those bastards at VW changed the location of the exhaust exit from the body and the placement of the rear most hanger between the 8V and the 16V! Balls! So another hour later I'd managed to reshape the tailpipe and move the hanger. The 16V will have to wait for its muffler!

So, his car is a touch louder with a nice rich tone to it and it seems we managed to pick up yet a little more power. Might have even made enough of a difference that a little retuning of the Megasquirt is in order! Another pretty successful project and Mike did all the wrenching! ;^) Did I mention this car is just a kick in the ass to drive??

I also managed to drain the tank and replace the crimped tank to pump hose on the 81 I've been working on. That 2 year old gas smelled so bad it almost made me puke!

So, what have you all been up to?
Dan