Audi 90 (1985) type 85 with 7A Conversion

[quattrostyle]

lovely induction noise

[Ryss]

Thanks for the comments guys.

Reconditioned the prop shaft, and went for a dyno tune.

After a quick look they decided to scrap all my hard work on the Maps and start afresh with different parameters. Whipped the propshaft off and put the car on a two wheel dyno, with the center diff locked. (do not try this on a modern quattro).



Fine tuned the car on the dyno and now it goes very smoothly, in all rev ranges. Not so good news. is we are way short of the sort of power I was expecting. 130 Kw (175BHP)@ 6000 (164Km/Hr @6500 in 4th) and 220Nm @ 4500 rpm. Torque curve looks amazing and comes in, in bucket loads. So no out and out bragging rights, and I now have an excuse for slow lap times. Fantastic to watch someone, who knows his stuff, go to work.

I was hoping to get around 150 Kw, based on the 120Kw standard, and the extra form aftermarket ECU, injectors, porting, cam and dual throttle bodies. Could still do a tubular exhaust manifold, but do not believe the cost will be worth it.

Main problem may be the cam grind, which I specified at the time that I wanted to retain torque, smooth idling, street driveablity and get to high RPM easily. This is exactly what I got.



However, the car is almost underivable in two wheel drive with that sort of power and wheel spins, when changing down to third and flooring it. I think the dyno is conservative in comparison to other dynos. But lets see how she does on the track.

My fancy twin throttle body makes 2Kw on top end but does make, getting there, a little faster.

Will try and make a 0-60MPH video soon. Very pleased with how the car accelerates. Not so happy with rather flat performance between 3 and 4000RPM.

This weekend I had a lucky break. I was fiddling with the maps to see if I could get the idling a bit better and while doing, with the engine running, I heard something let go in the engine bay and a lot of water escaping. Checked the temp and it was 86 degrees C. Checked the water bottle but that was fine then saw the rubber water pipe where it connects to the thermostat housing had burst, almost right round the pipe, just above the actual connection. Closer inspection shows no reinforcing inside the rubber.OE part on top of it.

Lucky this did not happen while I was burning round the track, as I might not have heard it or the audible alarm and cooked the engine.

On Sat morning I had new front shocks, bump stops, dust covers and pivot bearings fitted and wheel alignment done. Suspension is now right. Just need to replace ARB rubber bushes with polyurethane as well as the gearbox mountings.

[20Vcqdriver]

Keep looking or advertise for the factory tubular 5 into 1. They were supposed to be good for an extra 7bhp at least . Personally I'd always aim for max torque over ultimate bhp every time.

[andy10v]

You can get the factory tubular headers for less than £100 over here.

Good luck with your next crazy idea!

[ralleyquattro]

You can get the factory tubular headers for less than £100 over here.

Good luck with your next crazy idea!

I have one with downpipe and both shields for a lot less than that.

http://www.audifans.com/marketplace/show.php?table=pm_audifans_Parts&id=17622

[dunstan]

Nice car and like the thinking. Looks like good power and torque to me. 10 bhp better than supposed factory figures is not easy to come by on a n-a engine so well done.

[Ryss]

A belated thanks for the comments.

Fiddled with maps and got 134Kw on another dyno.

Did a few races on the track and public days. Managed to blow the head gasket big time due to detonation. Ran out of fuel due to surge in the tank when the fuel level was too low.

So had to fix that and could not get new stretch bolts for the motor in South Africa. Eventually bought 2 sets for a Golf 9A. Now running with Octane booster and some more fine tuning.

I wish I knew what the ignition curve was for this motor. I am currently running 30 degrees advance at 7200RPM. Think I could go to 32, but rather be save than sorry.
I do not have knock sensors with current ECU. Will get a stand alone knock sensor kit in the near future, hopefully.

Handling of the car on the track is seriously too soft and lots of body roll. No limited slip diffs so nervous about going too stiff and lifting inside wheels. Here is a vid clip of me been followed by a mate in an Audi S8 on an open track day. http://youtu.be/HxqNEPdKJMs

Long term plan is to fit S2 suspension (front and Back) but funds are short.

However having some serious fun on the track. If I encounter any understeer on the track I just jump on the loud peddle and the back steps out by a very controlled amount and then steers round the corner as easy as pie. Fast corners are another situation. Sure car can handle them but driver suffers from nerves. Busy growing some cast iron b###s

Other than that have started respraying the car white, with red, silver and black stripes running down the sides at 45 degrees, on the front and back. Had some major rust that needed to be repaired.

Right A Pillar.







Left A Pillar













Final repair will be done when the windscreen is removed .

[TimE-J]

Very interesting project, good luck!

[Ryss]

Time for update.

Got head and blown head gasket sorted out. Made car look a bit better with some artwork.





Added a fibreglass engine under tray.


Done five races (so still an old age novice) and car is going like a dream in terms if reliability. Had toe in set front and back and this has made a difference in making the back a little more tail happy and counters the understeer.

Last race started with 8 laps in the wet, and had too much fun. Started 11th and ended 2nd, despite 2 spin offs. Quattro Rules big time.

Here is a link to an in car video of just over 11 min. 1 and a bit laps cut out. First lap and a bit and last lap are the interesting bits. Excuse the language of me cursing my stupidity. I run with the center diff locked. Makes a big difference to the car's stability under braking. Hope you enjoy and have a few chuckles.

Video

[Tonks4x4]

Well Done.... Do you go into different race class if you fit turbo?

You want to see if there is any rally races with the current spec, the quattro will stand out even more on the loose stuff

[SE_30]

Just my honest opinion, them wheels do not suit the car at all. Hope you have some period wheels for it good work otherwise

[Ryss]

Well Done.... Do you go into different race class if you fit turbo?

You want to see if there is any rally races with the current spec, the quattro will stand out even more on the loose stuff

Seriously contemplating fitting a AAN and 6 spd box. Not within the rules so will have to move to another class. Also have a Audi 90 b3 , so that may be a better car for the AAN, but its not a quattro. Full roll cage and the conversion does not look that bad.

First I need to learn how to handle and get the max out of what I have.

Not going rallying in a street/track car. Suspension set up is too different and not have the travel, but with you on the idea. Will just hope for lots of rainy race days.

[Tonks4x4]

My suggestion would be to get a set of coil overs for the typ 85, convert everything to solid mounts, ie Engine, gearbox, subframes etc.

Flare the arches so you can get some wider tyres on when its lowered.

Then rebuild the AAN with stupidly lots of power. convert it to ABY spec as it's easier to fit in.

Then when you have had a year racing the current setup.
put the 20vt into the typ85 and put your nice 7A into the front wheel drive car.

[Ryss]

Good advice. Was thinking (too much and too many variations) of fitting S2 struts, b3 knuckels (4 x 108 pcd) as have parts on hand. Will allow some negative camber adjustment and bigger shocks.

Stage 2 would be coils overs which will be will be easier to get for S2\b3.


But like your clarity of thought. Thanks

[Ryss]

My suggestion would be to get a set of coil overs for the typ 85, convert everything to solid mounts, ie Engine, gearbox, subframes etc.

Flare the arches so you can get some wider tyres on when its lowered.

Then rebuild the AAN with stupidly lots of power. convert it to ABY spec as it's easier to fit in.

Then when you have had a year racing the current setup.
put the 20vt into the typ85 and put your nice 7A into the front wheel drive car.

Well It's all your fault.. Tonks4x4

Recently fitted S2 struts and hubs and changed the springs to some I salvaged from the rear of a C4 ,2.8 fwd. Also increased tyre pressure to 3Bar. What a difference. No more under steer and about 2 seconds a lap faster faster.(+- 2%)

Car is still running too high in front so some more work required, but now the car feels so much better, I feel I can start exploiting more of its potential.

Fitted a larger diameter rear exhaust pipe and with colder plugs and octane booster, seem to have sorted the detonation problem I was having. Power from the 7A is now up to 139Kw. (185bhp) and timing could still be a little conservative.

ABY enigine removed from my S2 that I crashed and will most likely be fitted to this 90 next year. Also shock towers will be moved inboard and back and wider fenders and tyres as recommended.

S2 will get a 1996 4.2 V8 transplant so looking for a flywheel.