Dace's '94 //s4 - Now For Sale!

[UrSobsessed]

I believe altitude has much to do with problems I have been having. I have tried to get this thing to idle smoothly up here, but the only way to do it up to this point has been run it pig rich and then fine tune with PID settings and spark advance. When I adjust the fuel towards stoich, the idle gets really rough and bounces around. Typical of a lean mixture. When I was driving around at 500' elev. the car was a lot easier to tune.

The fuel vapors from the tank seem to be contributing to what I have going on. With the the system being mostly closed while the engine is running, I can't say how much altitude figures in here but I want to say a decent amount. I figure having the N80 open only on decel will help with more consistent lambda readings.

Yeah, the baro corr in vems is poor. I was going on a trip covering a range of 8k' altitude and really just wanted to see how it worked. Closed loop adjustments were what I did when I was on my trip, which was far more dependable.

[UrSobsessed]

Been a while, so I'll update quickly. I got the N80 provision set up in VEMS which helped get the fueling under control, especially at idle. What I did can be found HERE:http://forums.quattroworld.com/s4s6/msgs/181738.phtml. The car has been running well, but was a bit sluggish down low. I was thinking tuning the timing map would help things out. I was waiting for some dyno time and expertise to do this.

Meanwhile, I've been chasing down a rear end growl that popped up when I had my center driveshaft rebuilt. It happens only on decel above 60mph. It's proving to be hard to find.

I took the car to have some exhaust work done to Dave Jones at S-Line Motorsport and had him do a leak down test on the motor. I've been suspecting a fair amount of blow-by as my oil gets really black in a short amount of miles after an oil change. I wasn't getting much oil in the catch can so I wasn't sure how bad things were. I was hoping this test would give me an idea of where things are.

Test results: Cylinder 1=4%, 2=5%, 3=18%, 4=40%, 5=40%.

Sucks.

I was hoping this engine would last another year, more likely two, until I could get everything together for the 2.6l that I want to build. I'm nowhere near being able to get that engine together now. So I've decided to have Dave build up a bottom end for me. It's going to be pretty basic, with the necessary upgrades to make the bottom end handle the extra power I want from it. I'll end up being a 2.3l.

I'm looking at:
Ross 83mm custom treated pistons and the block bored to match
scat rods
ARP hardware

At that time, I'm also going to send my 3071 to forced performance for the billet wheel upgrade. The head was redone 20k ago, but I would like to do some more with it. Unfortunately, I don't have the cash right now. Dave presented me with a "wish list" of things I could do with the head which was killing me! Originally I wanted to put in a stiffer spring/ti retainer kit with some oversized valves and port match/polish the head, but that's going to have to wait.

I didn't want to do this so soon, but I'm excited to get this thing some more sack!

[Hapster]

Hey Dace

I do have a set of 880cc injectors that would match up with the 2.3/GTx3071 very nicely. It ran the Monster to about 600hp on E85.

Hap

[UrSobsessed]

Thanks Hap. YGM.

[UrSobsessed]

So Hungry went under the knife today. Dr. Dave Jones at S-line Motorsport in Denver will be performing the surgery.

The build is going to look something like this:

Bottom end:
AAN block, decked and cylinders bored to 83mm-displacement will be 2/3l
Ross custom pistons, coated
OE main and rod bearings
ARP main and rod studs/nuts
Scat rods

Top end:
High rate valve springs/ti retainers
Ferrea .5mm oversize intake/exhaust valves

Misc:
3073 HTA billet wheel upgrade(from 3071)
.82 hotside(up from .63)
Southbend stage 4 "extreme street" clutch

There will be some other little odds and ends happening as well, but that's the gist of it.

I'm kinda excited

Once it gets broken in, I'm going to replace my 630cc injectors with some 880cc's, dial VEMS and then see about really turning up the wick now that the bottom end can handle mo powah! :woowoo:

If anyone has any thoughts or ideas about this, please post 'em up!

[Hapster]

Can't say much for the name Hungry. Since I named the Fridge and the Monster, how about the Wooster?

Hap, with some kind of name near Everboost, Maguire

[200 Avant]

Dace,

Did I see your car parked in front of Totally Wired in Fraser two Saturdays ago? I'll be up this Saturday to ride the valley.

Car looks nice..

As for your rebuild let me know if you need advise on machine shops. So far I've logged over 20K on my build with "zero" issues other than an oil pan leak. I'm really pleased with the work that was done and the reliability.

Oh yea. The car LOVES Berthoud Pass Motor Sports complex and pulls like a freight train all the way with no altitude issues. I've recently had 2 super fun early morning runs to the top

[UrSobsessed]

Yeah Tom, that was mine, thanks! I work right next door at Wild Horse Catering. Stop by sometime when you're up. Where you planning on riding?

I won't need a machine shop as Dave is doing the build this time around. I will be building something down the road, however, so I'll get with you on that when the time comes...

BPMSC is quite fun, ain't it;) They have been paving over some of the damaged spots so it's better now on some of those turns.

[UrSobsessed]

Things are in the process of going back together. I can't wait(that hardly sh!t was a lie). The turbo gotz some billetness and a little bit of an enlargement. Yep, the plain ol' 3071 became an HTA 3073. Should be tasty.


The head came back in a head bag, and low and behold, with some .5mm oversize intake and exhaust valves! How did those get there? :wink:


And then there's the block, all bored to 83mm and honed to perfectioness.


Thanks to Hap for taking the pix!

A few other things are going on also. More to come...

[RSCoupe]

I like what you're doing here. :-)

[UrSobsessed]

Thanks!

[UrSobsessed]

So this thing is SO much bigger than my 3071 housing that some material had to be taken off of it and the EM to get it to fit right. Seems so much bigger for just 2mm of exducer diameter. I didn't expect this.

It weighs quite a bit more too. Dave had to fab up some brackets to brace the turbo to keep the turbo => EM nuts and the EM=>head nuts from coming loose. I've had the turbo=>EM nuts loosen up on me twice. I've even lost studs from both one time. Sucked.

Anyone else notice this? Dave said that he's seen this happen a few times with the Wagner manifold....

[EDIGREG]

I frequently had EM->turbo nuts loosen on me with the Wagner/30R setup. EM->head nuts loosen over time, even with the factory parts. V-bands FTW

[Hank]

You can request the turbo with different compressor covers btw. You got the big .70AR T04S cover, but you could have got a smaller t04B cover that would not have needed modification. They don't mention it on the site, but you can do it.

[UrSobsessed]

@ Ed: Yeah man, v-bands will be on the next set up I go with, right there at the end of one of Hank's tasty manifolds!

@ Hank: I did not know that. Dave dealt with them. He told them about my build and what I wanted to do and that's what they recommended. Will this cover cause it to spool a bit slower, is it more about fit?

[Hank]

Yeah, the .70 AR will flow more volume overall at a slight lag give up. Too bad you ground it. FP would likely swap it out otherwise.

[UrSobsessed]

I hear you there. Well, we shall see what this one will do...

[chaloux]

I'm pretty stoked to see how this compares to a 3071

[Mushasho!]

to be fair we'd need a 3071 on a head that has .5mm oversize intake and exhaust valves & a block bored to 83mm to compare...

[UrSobsessed]

True. I'd bet that the 3071 would do better with this set up than on the stock block/head.

[chaloux]

meh those are fairly small mods - and everything is relative. Marc was telling me they pushed Janis 3071 to 480whp. So "better" or "compared to" for me just means vs spool at about 4k and around 350ish whp on reasonable ~30 or lower psi.

[UrSobsessed]

My point is that the 3071 would enjoy a better breather than the stock set up, not that it can't handle the powah.

[chaloux]

Yeah I understand, but it'll still be a decent comparison.

[popdemonic]

look great Dace!

[UrSobsessed]

When disassembling my motor, Dave found this:


It's the steel ring that's put in the Wagner/034 RS2 HO EM that's been machined for a k26 flange. I guess it's there to help locate the turbo/hold it in place better?

Anyway, this one was cooked, as you can see. I asked if high EGT's could be the culprit, but Dave said there was no other evidence in my engine of that. He wasn't sure why it looked so bad. Not only is it cooked, but it's also warped.

What do you guys think? Cheap metal?

Here are some more pix: