Posche 924 Audi 4.2 V8 ABZ

Hy guys

My name is Karl and I'm from Latvia. I would like to introduce you with little background of this project.
It was October 2011 and I had a chance to get one good looking 924, NA with nice fiberglass wide-body, GOTTI rims but with 3 speed automatic.
[You must be registered and logged in to see this image.]

So the first thing to do was transmission swap. These old hydro-mechanical automatic gearboxes are real pain. It took almost a year for me to collect all the needed information to do this swap. Getting a used Porsche manual 5-speed unit was impossible so i decided to go with an Audi 016 gearbox.
After some research bought used 016 AAZ from Audi 100, then managed to get a torque tube from a manual car - they are different and so the shafts are.
Some fabrication work and gearbox was mounted on a car:
[You must be registered and logged in to see this image.]

Decided to install a central slave bearing from Renault Master van.
[You must be registered and logged in to see this image.]

Custom gearbox mounts
[You must be registered and logged in to see this image.]

Installed clutch master cilinder from Renault Laguna
[You must be registered and logged in to see this image.]

Custom rear axles - one half from Audi, other from Porsche
[You must be registered and logged in to see this image.]

Finally on September 2013 I did the first test drive and was amazed about radical changes in performance compared to automatic setup.
[You must be registered and logged in to see this image.]

Now I can focus on the main part of this project - engine swap. I wanted to stay with Audi engines, because i5, V6, V8 shares the same bolt pattern as 924. My first choice was 20 VT AAN from Audi S2, but these engines are rare and expensive. Last month a friend of mine offered me 4,2 l V8 engine code ABZ from 1995 Audi A8 Quattro - 300 HP stock. It was in great condition so I couldn't resist buying it.
[You must be registered and logged in to see this image.]

So another ABZ swap starts...

Saying goodbye to the old 2,0 NA ...
[You must be registered and logged in to see this image.]

V8 is waiting to be swapped in...
[You must be registered and logged in to see this image.]

Stock exhaust manifolds doesn't fit, but even if they would, it would take as much time modifying them as building new ones. So removed them and put the engine back in.
[You must be registered and logged in to see this image.]

Now it sits too far forwards because stock oilpan hits crossmember. Another thing to consider is that 924 uses motor mounts attached to body frame instead of crossmember mounts as 944. To move engine back left side engine mount should be cut off and crossmember removed.
Now it sits pretty nice.
[You must be registered and logged in to see this image.]

Here is the main problem - oil pump is directly above steering rack and crossmember. My plan is to cut the body of oil pump and leave only pumping side removing pressure valve and oil inlet.
[You must be registered and logged in to see this image.]

That's the engine right there. I measured one at a local junker and it was the length of an American V6. I think it would be a perfect fit for a Mid-Engine 944, but you are doing a great job mounting it. Also if it were to sit further forwards, like your first pic, Could it be possible to keep the factory brake booster?

Coool project...nice work...great job solving so many challengers...and "Decided to install a central slave bearing from Renault Master van." is brilliant ! And so is your English  

xschop wrote:That's the engine right there. I measured one at a local junker and it was the length of an American V6. I think it would be a perfect fit for a Mid-Engine 944, but you are doing a great job mounting it. Also if it were to sit further forwards, like your first pic, Could it be possible to keep the factory brake booster?

Thanks
Yes, it's very compact and short engine - only 46 cm long, actually shorter than stock 2,0 NA which is 56 cm long.
It's possible to keep the factory booster if the engine is moved 40 cm forwards(clearance between engine block and firewall), but then it hits pop-up lights mechanism. If the conversion is done that way it's possible to keep stock oil pan, so no changes to oil pump or oiling system is needed, but you have to make a bump on a hood. As the engine sits so far towards the front of the car, it destroys car's near perfect weight balance. Although doing conversion this way would be easier, it would be absolutely wrong from engineers point of view.

944convert wrote:Coool project...nice work...great job solving so many challengers...and "Decided to install a central slave bearing from Renault Master van." is brilliant ! And so is your English  

Thanks, I'm glad you like it  

Removed the timing belt today. Pretty easy task until got to the harmonic balancer. It was impossible to remove 4 hex bolts holding balancer to timing belt pulley, so it took some time to drill them out. These bolts were so hard, that I had to use HSS Co drill bit.
Then I carefully checked harmonic balancer...pulley and outer vibration dampening ring was far from concentric because of deteriorated rubber. As this will be performance engine, I removed the outer ring from pulley to reduce engine's inertial mass. Would be interesting to calculate how much torque you loose when accelerating in first gear due to all this stuff. In my application generator will be the only thing driven by accessory belt - no AC pump, no power steering pump, no crank driven fan...no harmonic balancer. And if we add custom lightweight flywheel, we can expect some real torque gains when accelerating. Maybe it sounds weird but we loose 15..20% of torque in first gear when accelerating hard. These 15..20% are used to accelerate all rotating parts like camshafts, crankshaft, pulleys, flywheel, clutch, axles, wheels...

Will keep following this over the next weeks, I'm half way into fitting a Volvo T5 to my 944 but have a Audi V8 which could happily go in either

Some progress...

After swapping the engine in and out several times I was finally sure about engine position in engine bay. My aim was to mount the engine as far back as possible and still use factory oil pump. This means 85 mm spacer between bell housing and torque tube. To take any further measurements the spacer was needed, so i made one from wooden block 120*110*85 mm.
[You must be registered and logged in to see this image.]

Then it was possible to see where the engine is actually located.
[You must be registered and logged in to see this image.]
After this I realized that the aluminum sump has to be removed because it would take too much time and effort to modify for use in this setup. So a new sump has to be made.
[You must be registered and logged in to see this image.]
Now the engine clears cross-member, but not the steering rack, so it should be lowered. I did it very simple - screwed it one hole lower than stock, so upper mountings could be cut from cross-member and welded back at the bottom of the cross-member.
[You must be registered and logged in to see this image.]
When steering rack is lowered, it hits cross-member..some minor modification is needed.  

Next thing in to-do list was the oil pump. As you can see in pictures oil pressure valve and oil pick-up tube is hitting the steering rack even if it's lowered so the oil pump must be modified.
[You must be registered and logged in to see this image.]
Pressure valve housing and oil pick up tube was cut down. Idea is to use external oil pressure valve and weld back custom pick up tube.

Finally I was able to start designing a new sump.
[You must be registered and logged in to see this image.]
Result..
[You must be registered and logged in to see this image.]
Tried to keep the things very simple because I will be doing all the welding by myself. Oil capacity is 6,3 l. Sump will be made from 2.8 mm steel. I know it's little bit too thick, but i had this material laying around. In this V8 sump is part of an engine block. Transmission bolts directly to sump with 2 M10 bolts so it has to be tough and durable.
[You must be registered and logged in to see this image.]

Test fit
[You must be registered and logged in to see this image.]

Everything looks good so far except the red marker area. There is only 0,1 mm gap between the steering rack and sump.
Now it's ok.
[You must be registered and logged in to see this image.]

Starts looking like a sump
[You must be registered and logged in to see this image.]

Out of context  - here is length comparison between stock and V8 engine
[You must be registered and logged in to see this image.]

Did a quick modification to harmonic balancer..now it's just an lightweight aluminum pulley
[You must be registered and logged in to see this image.]" />

Very interesting project and nice bodywork on that car. In the beginning of the 1990's when I got my drivers licence it was the dream to have a 924 with that bodykit. A 944 was extremely expensive at that time.

As many "swappers" have experienced, there is not much space above the cross member on our cars. When I realized that the oil pan was way too big on my engine, I first build a pan where the sump (or reservoir) was in front of the cross member. But there was no way I could have any front sway bar on the car then, unless it was going to be very very low = under the oil pan. If I was going to mount it in front of the pan, it was too far away from the suspension.

Can you have a front sway bar on the car, with this new oil pan?

I lowered the steering rack 1 cm (0.4 inch) on my car, so it was flush with the cross member. I was a little concerned about how that affected the handling of the car. I don't like the idea of lowering the complete cross member and I wasn't that happy about lowering the rack either, but something had to be done, so I could get more clearance for the oil pan. I have taken a few testruns in the car on bumpy roads, and apparently it hasn't affected the handling.

But when moving the steering rack too much away from the original position, you may achieve something that is called "bump steer". This means that when the car is going over a road bump, the wheels turns left and right, even though the steering wheel is held in the same place. This is because something is not aligned anymore.

Now and then I was thinking about a dry sump oil system. Then you can have a complete flat oil pan and an external oilpump driven by a belt. Then you probably wouldn't have to change anything in the steering geometry.

For now I have ditched that idea, since my modified oil pan/system works.

Fantastic work, you have some great skills! Looking forward to seeing this finished, what is the HP rating of that engine?

HorizonblueDK wrote:Very interesting project and nice bodywork on that car. In the beginning of the 1990's when I got my drivers licence it was the dream to have a 924 with that bodykit. A 944 was extremely expensive at that time.

As many "swappers" have experienced, there is not much space above the cross member on our cars. When I realized that the oil pan was way too big on my engine, I first build a pan where the sump (or reservoir) was in front of the cross member. But there was no way I could have any front sway bar on the car then, unless it was going to be very very low = under the oil pan. If I was going to mount it in front of the pan, it was too far away from the suspension.

Can you have a front sway bar on the car, with this new oil pan?

I lowered the steering rack 1 cm (0.4 inch) on my car, so it was flush with the cross member. I was a little concerned about how that affected the handling of the car. I don't like the idea of lowering the complete cross member and I wasn't that happy about lowering the rack either, but something had to be done, so I could get more clearance for the oil pan. I have taken a few testruns in the car on bumpy roads, and apparently it hasn't affected the handling.

But when moving the steering rack too much away from the original position, you may achieve something that is called "bump steer". This means that when the car is going over a road bump, the wheels turns left and right, even though the steering wheel is held in the same place. This is because something is not aligned anymore.

Now and then I was thinking about a dry sump oil system. Then you can have a complete flat oil pan and an external oilpump driven by a belt. Then you probably wouldn't have to change anything in the steering geometry.

For now I have ditched that idea, since my modified oil pan/system works.

It's possible to have sway bar in my setup. As it will sit further from suspension, it should be made thicker, because of greater momentum created by longer lever. Early 924 didn't have  sway bar at all.

Talking about bump steer. Every car has this. Theoretically you get no bump steer only when driving completely straight and steering system and suspension is geometrically synchronized. That means lower control arm is parallel and the same length as tie-rod. In reality it's not so perfect. Bump steer basically is trigonometric function of suspension travel. So if you reduce suspension travel(harder springs), you significantly reduce bump steer.

So I will stay with your idea about modified sump and custom sway-bar.

87-944S wrote:Fantastic work, you have some great skills!  Looking forward to seeing this finished, what is the HP rating of that engine?

Thanks,

It's 300 HP stock. Larger injectors and ECU from Audi S6 rises this to 340 HP.

Any updates?

That is a awesome 924 build. looks like a lot of fab work but it looks good so far. My first Porsche was a 77 924 "Martini and Rossi Championship edition", then 4 or 5 914's. If I could find another martini 924 I would own it. With some power upgrades of course.

Who created the body kit?   

The bodykit is made by a german company called "Folger"

Hi guys, this is a very interesting discussion, and perhaps the only one around the web with the Audi ABZ V8 engine on 924 , I'm also working on a 924 Turbo and the engine although the turbo version was not a thrilling me... the idea is that once finished bodywork and interior i will find a more interesting motorization and my choice is precisely the ABZ Audi.
I hope Kazha333 update his working progress to know how he solved the two major problems of this swap , which from what I understand , are the front cross member with the oil sump and the brake booster, without leaving the steering box with its shaft ;-)
Thank you all and I am connected

Very interesting project - love the wheels too!

Hello, guys!

It's been a while since my last post. Long story short: ABZ conversion can be done, but it takes too much fabrication and engineering.

I finished the oilpan, relocated master cylinder, removed vacuum booster, made adapter for master cylinder to firewall, installed engine in its place...but engine transplantation rules in my country don't allow such modifications, so car would be track use only.

Last year I decided to put up all this swap and started a new one - 1,8 T AEB swap. Searched the internet and found out that some guys had already done this.

A shame to hear that it didn't work out. Could be fun to see a 924 with an Audi V8 in. Until now, I haven't seen a 924/944 with an Audi V8 in, running. There is another guy on the board who has started a conversion, but he has also been quiet for some time. Maybe he ran into the same problems....

That’s awesome

As said a shame this didn’t work out, good read.