I hope you are right! its funny, ive spent so much time and effort on this car, but only driven it about half a mile. Plus, never driven a diesel quattro, so i feel like i dont even know its personality yet. I cant wait to meet it.
Audi 90 quattro TDI: gearing questions
- Thread starter vtpsd
- Start date
3baudios
Veteran Member
- Joined
- Mar 20, 2008
- Location
- winston NC
- TDI
- 93 eurovan AHU (almost), 88Fummins, 01 alh golf, 91 toyota alh
all that low end TQ will be a blast. I am very thankful for your documentation of this swap
nitec
Vendor
I like that EGT probe - that's pretty much where I was going to put mine as well...what about an exhaust pressure sensor in the same area? it would be good to get that data too
finished the exhaust, left room for a resonator or small muffler. Not sure yet if I will want one. Its a bit hard to tell loudness from just a free rev.
The exhaust is all stainless, and i used 309 wire in my MIG welder with solar flux type b in lieu of backpurging. It kind of sucked. I was only able to lay down a few welds that looked good. They did appear to be nice and solid, not porous though, overall Im pleased with the finished product.
I made my own tip from just cutting and welding a mandrel bent 180 in 14 gauge polished stainless. Used that factory hangers. The hangers are made out of 3/4" x 1/8" stainless flat bar.
The exhaust is all stainless, and i used 309 wire in my MIG welder with solar flux type b in lieu of backpurging. It kind of sucked. I was only able to lay down a few welds that looked good. They did appear to be nice and solid, not porous though, overall Im pleased with the finished product.
I made my own tip from just cutting and welding a mandrel bent 180 in 14 gauge polished stainless. Used that factory hangers. The hangers are made out of 3/4" x 1/8" stainless flat bar.
injectors back from being balanced and flow tested.
new glow plugs
put it on the winter wheels and drove it around the yard. That felt shockingly awesome. Everything seems copecetic. Still running wiring just sitting in the engine bay, and no throttle control from the cabin, so just idleing. It was amazing to see it out in the sun. Its been couped up for 3 years in my shop. The engine bay looks so good in sunlight. I cant wait to repair the little paint issues, replace the trim, put on my new wheels and clean it up.
the red barn in the background is my shop where it has lived for 3 years.
straight pipe test, might need a resonator. Smokes a lot, but the coolant temp sensor is sitting in the air, and I have no idea where the IQ is, so that should bring it down some when dialed in.
https://www.youtube.com/watch?v=visG7zLbUEM
new glow plugs
put it on the winter wheels and drove it around the yard. That felt shockingly awesome. Everything seems copecetic. Still running wiring just sitting in the engine bay, and no throttle control from the cabin, so just idleing. It was amazing to see it out in the sun. Its been couped up for 3 years in my shop. The engine bay looks so good in sunlight. I cant wait to repair the little paint issues, replace the trim, put on my new wheels and clean it up.
the red barn in the background is my shop where it has lived for 3 years.
straight pipe test, might need a resonator. Smokes a lot, but the coolant temp sensor is sitting in the air, and I have no idea where the IQ is, so that should bring it down some when dialed in.
https://www.youtube.com/watch?v=visG7zLbUEM
nitec
Vendor
lol...someone's rollin coal 
3baudios
Veteran Member
- Joined
- Mar 20, 2008
- Location
- winston NC
- TDI
- 93 eurovan AHU (almost), 88Fummins, 01 alh golf, 91 toyota alh
Your car is awesome Dana
nitec
Vendor
hey which EGT probe/gauge did you actually go with? I'm gonna pick one up as well
I got the McNally Boost/EGT combo. I like the idea and the look matches the audi interior very well. However, I have since read some not-great things about them.
Also, when I ordered, I chose a 0-40 psi gauge, and received a 0-30. They sent me the right one quickly, so not a big deal.
Am doing wiring right now, so I haven't even powered it up yet. I like the idea of it, hopefully it works well.
Also, when I ordered, I chose a 0-40 psi gauge, and received a 0-30. They sent me the right one quickly, so not a big deal.
Am doing wiring right now, so I haven't even powered it up yet. I like the idea of it, hopefully it works well.
its springtime in VT, and its time for the annual MK4 oil pan smash.
Can you spot my quick change drain plug?
I like wiring harness work, but damnit I forgot how much I don't like pulling the b3 dash. What a cluster.
it puked its guts out
removed the internal 250kpa map sensor and ran wires in prep for an external 3bar mk4 style unit.
my eyesight is not that good, these tiny pins were hard for me to do.
connector and wire pigtails to add into harness and run to new external MAP sensor
Can you spot my quick change drain plug?
I like wiring harness work, but damnit I forgot how much I don't like pulling the b3 dash. What a cluster.
it puked its guts out
removed the internal 250kpa map sensor and ran wires in prep for an external 3bar mk4 style unit.
my eyesight is not that good, these tiny pins were hard for me to do.
connector and wire pigtails to add into harness and run to new external MAP sensor
Baumeister
Veteran Member
- Joined
- Feb 19, 2004
- Location
- Auburn, CA
- TDI
- '15 Beetle Convertible, '03 New Beetle TDI 5sp, '94 Audi Cabriolet(AFN swap in progress)
Looking good! I'm still in the "parts collecting" phase of my '94 Audi cabriolet swap and stuck catching up on reno projects around the house.
That ECU location seems really ODD. Mine's under the back seat. I'm thinking I'll likely keep it there but I'll decide that after seeing how much splicing the harness will take.
While you've got that out its a great time to replace that heater core. Mine blew last summer and it still smells like stale coolant inside. (I bypassed it for now)
OE B4 A/C evap cores have been on on clearance from Audi for $70 or so if you're keeping the A/C.
That ECU location seems really ODD. Mine's under the back seat. I'm thinking I'll likely keep it there but I'll decide that after seeing how much splicing the harness will take.
While you've got that out its a great time to replace that heater core. Mine blew last summer and it still smells like stale coolant inside. (I bypassed it for now)
OE B4 A/C evap cores have been on on clearance from Audi for $70 or so if you're keeping the A/C.
I am definitely changing the heater core while I'm in there. The ECU is there for all of the older cars b3 sedans and coupes. Strange place, but it fits well. Not keeping AC on this car. I never use it in VT, and the simplicity of getting rid of an ancient and broken system is nice.
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been slogging through the wiring, finally its coming together. The chassis side is pretty much done, got to finalize the mess in the cabin still, but hit a pretty big milestone yesterday. Fully functioning ECU and engine with zero trouble codes.
Cleared another hurdle that I have been dreading. I have a working gas pedal.
Obviously the TDI is drive by wire and the audi is cable throttle. Turns out, throttle pedal placement is very important and precise. The pedal needs to sit at the right level to be even with the brake when the brake is applied for proper left foot braking and blip downshift action. Several of my first revisions of using the mk3 pot and the audi pedal proved that is just didn't feel right. Fine for a truck maybe, but i drive hard fast and sideways on the most challenging road in the state every day. It has to be right.
The mk3 has this cable operated throttle potentiometer that will not fit under the audi dash and give any kind of reasonable throttle action. I noticed my mk4 has a much better and more compact pedal and apparently they have the same outputs and same number of pins.
mk3 on left, mk4 on right.
Problem is, the mk4 pedal doesn't really fit right either, so I ended up with a strange hybrid of the original audi lower pedal bonded to the mk4 potentiometer with a custom bracket to mount to the brake booster studs. The result is very good. I carefully measured the stock pedal placement, and this is right on the money.
Out comes the same old 3/16" winch plate for some more cannibalization
pedal side mount built
mk3 connector ready for de-pinning. It was pretty awesome that I was able to just put these pins in the mk4 plug and it all worked perfectly with no codes or anything.
bracket done
Its pretty uggo, but it works great, and you can only see the pedal with the dash in.
Obviously the TDI is drive by wire and the audi is cable throttle. Turns out, throttle pedal placement is very important and precise. The pedal needs to sit at the right level to be even with the brake when the brake is applied for proper left foot braking and blip downshift action. Several of my first revisions of using the mk3 pot and the audi pedal proved that is just didn't feel right. Fine for a truck maybe, but i drive hard fast and sideways on the most challenging road in the state every day. It has to be right.
The mk3 has this cable operated throttle potentiometer that will not fit under the audi dash and give any kind of reasonable throttle action. I noticed my mk4 has a much better and more compact pedal and apparently they have the same outputs and same number of pins.
mk3 on left, mk4 on right.
Problem is, the mk4 pedal doesn't really fit right either, so I ended up with a strange hybrid of the original audi lower pedal bonded to the mk4 potentiometer with a custom bracket to mount to the brake booster studs. The result is very good. I carefully measured the stock pedal placement, and this is right on the money.
Out comes the same old 3/16" winch plate for some more cannibalization
pedal side mount built
mk3 connector ready for de-pinning. It was pretty awesome that I was able to just put these pins in the mk4 plug and it all worked perfectly with no codes or anything.
bracket done
Its pretty uggo, but it works great, and you can only see the pedal with the dash in.
been driving this now for a week or so. Have about 300 miles on it. Its awesome, pretty fast too. Lots of tweaking to IQ and timing happening, but I am getting it dialed in.
I have a 900 mile roadtrip to a car show coming up this Friday, so that will be cool. Still needs lots of little work on the body and interior to be finished. Its also pretty smokey at WOT, going to add a little more boost (running 26 psi now). My EGTs climb a little bit into the 1600's at full bore. Hopefully a little more air will cool it down, if not, I'll have the fueling reduced, then maybe try an 11mm pump.
I will add a bunch more pics later when I get some time. Lots of work has happened since the last update.
I have a 900 mile roadtrip to a car show coming up this Friday, so that will be cool. Still needs lots of little work on the body and interior to be finished. Its also pretty smokey at WOT, going to add a little more boost (running 26 psi now). My EGTs climb a little bit into the 1600's at full bore. Hopefully a little more air will cool it down, if not, I'll have the fueling reduced, then maybe try an 11mm pump.
I will add a bunch more pics later when I get some time. Lots of work has happened since the last update.
I'm still running the 1.8t DMF and soutbend stage 3 daily. Pretty much ready to pull the trigger on the 240mm DMF and SRE clutch. My crank has the longer pilot bearing boss, and should fit a pilot bearing with the spacer with no issues.
For now the car runs and drives great, you just cant roll onto the power 100% in the higher gears in the torque peak.
For now the car runs and drives great, you just cant roll onto the power 100% in the higher gears in the torque peak.
You and me both! The holset is great, it spools very fast, it really doesnt feel laggy at all. My ALH car feels laggier, this is probably because the tune is pretty tight to control smoke. The tune on the audi is not scaled at all for boost, so it will dump fuel if you mat the throttle.
You are welcome to drive the car. I am very pleased with the cost and performance of the turbo. I am running it at 32psi now, running my iq at about 4.8, base timing at 62. Only a moderate haze at full boost, full throttle.
I am going to bump the timing up to around 70 tonight and call it good.
The power comes on quick enough that I can really get the thing sideways around corners on dirt roads. Its a blast.
I haven't really been taking many pictures. Been pushing hard to get this thing to Carlisle (car show in PA tomorrow, lots of old audis there). Its a bit ugly,rusty and primery but mechanically she is going well. Been daily driving it all week, and tweaking things/fixing all the little issues that come up with a build like this.
Random pics from the last month of busting ass.
Wiring hell!
hybriding a diesel euro cluster with my original. Correct working tach, glow plug light integrated, auto check and mph speedometer. I also swapped over the diesel fuel gauge. No more "unleaded fuel only"
clutch setup #2, a failure. DMF for gasser cannot handle torque at 2500 rpm.
1552 wheel fitment test.
clutch/fw #1 coming out
added a resonator last night. That made the car 100% better. This thing was way too drony and booming. The bigger turbo really lets a lot more 4 banger noise through, and it wasn't good.
This resonator is amazing. I cannot believe how much it quieted it down inside and out the car. The exhaust is a straight pipe otherwise. It totally makes the car, and it is extremely compact. Highly recommended. Not that a 4 banger ever really sounds good, but it improved this car 10 fold.
This is what it is
http://vibrantperformance.com/catal...id=45&osCsid=e25310b5de92ac6073924fca90612157
Random pics from the last month of busting ass.
Wiring hell!
hybriding a diesel euro cluster with my original. Correct working tach, glow plug light integrated, auto check and mph speedometer. I also swapped over the diesel fuel gauge. No more "unleaded fuel only"
clutch setup #2, a failure. DMF for gasser cannot handle torque at 2500 rpm.
1552 wheel fitment test.
clutch/fw #1 coming out
added a resonator last night. That made the car 100% better. This thing was way too drony and booming. The bigger turbo really lets a lot more 4 banger noise through, and it wasn't good.
This resonator is amazing. I cannot believe how much it quieted it down inside and out the car. The exhaust is a straight pipe otherwise. It totally makes the car, and it is extremely compact. Highly recommended. Not that a 4 banger ever really sounds good, but it improved this car 10 fold.
This is what it is
http://vibrantperformance.com/catal...id=45&osCsid=e25310b5de92ac6073924fca90612157
just got back from a 1000 mile roadtrip down to Carlisle PA for a show with a bunch of other old audis. Car did fantastic, not problems or hickups of any kind. It also surprised many people (including me) with how brutally it accelerates. It is able to hang through the first 3 gears with other cars that have over double the horsepower. Its quite funny to leave a stoplight with a cloud of black smoke and a nice patch of 4 wheel burnout rubber on the road.
I also checked my mpg for the first time on the trip back. We cruised between 75 and 100 and did MANY full throttle pulls. I was also trying to keep up with an RS4 and a 1.8t with a huge holset turbo the entire way.
I think it might have 50mpg with a cam, the belly pan installed and a lighter foot.
I also checked my mpg for the first time on the trip back. We cruised between 75 and 100 and did MANY full throttle pulls. I was also trying to keep up with an RS4 and a 1.8t with a huge holset turbo the entire way.
I think it might have 50mpg with a cam, the belly pan installed and a lighter foot.
oil_me
Veteran Member
That is so freaking outstanding. Quattrodieselicious. There's nothing tastier. I'm really happy for you.
https://www.youtube.com/watch?v=CHYhg1tjTzo
and random video my friend took of playing around on some gravel on the way to the Carlisle show. I should have grabbed second gear, it doesn't work quite the same in first gear as my gasser quattros.
and random video my friend took of playing around on some gravel on the way to the Carlisle show. I should have grabbed second gear, it doesn't work quite the same in first gear as my gasser quattros.