S2 into B4 Saloon & B3 / B4 Differences...

[Rusty]

Sorry to be lazy, just wondering why more B4 saloon conversions haven't been carried out? I understand that the I5 20vt basically bolts into the B3 I5 cars so it's easier. What are the problems when converting B4 cars? Is it just the engine mounts?

What are the differences B3 saloon to B4? Obviously the front pannels are different but are there any other changes that are worth noting?

If you had a B4 S2 Avant, would it all bolt into a B4 saloon with minimum fuss?

[HPmuirt]

Well according to Sonic's VIN decoder on S2Central.net, my ABY is a B3 platform car so I would say the differences are negligible

Cheers n

Si

[Rusty]

The coupe is a typ89cq thus the same as a typ89 = 'B3' so sounds about right. Don't forget that the coupe shell is nearly identical to taht of the original 1988 cars, hence why it's a bit old skool

Any ideas on I5 20vt into B4 V6 quattro?

[spink]

http://www.s2forum.com/forum/showthread.php?t=33772

[Acidburn]

following is different:

engine mounts (they didn't do a il5 in this country all we got was v6's etc)
b3 has the smaller rear arch flare
b3 rear seats don't fold down
b3 front arches have a smaller flare but this can be swapped
b3 boot lid is different
b3 front end
b3 has a different rear setup

It can be done and there is at least one person on here who's thinking about it/part of the way thru. Its easier with a b4 v6 then you just need to swap the engine mounts over (welded to the chassis) and start fitting the stuff from a s2 avant. Rotoryboy and flat on my back are currently starting these projects and if you search for threads by faaaast you will find a more detailed thread about this, i've just briefly skimmed over it.

[Rusty]

Sweet, cheers for the info. I guess if you started with an Avant then you can cut and shut the engine mount mountings.

Here's Faaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaast's original thread.

[S2central.net]

To be pedantic - that was my VIN decoder (which used to work... then I broke it... then Sonic the star man javascript/php/webmeister rebuilt it properly)...

Audi's platform and model terminology is really poor and not a wee bit confusing. It starts out all sensible then gets mixed up when you get into it.

The platform codes are as follows -

A_ for small cars (The A2 for example is a model that also shares platform label)
B_ for medium cars (Like the 80, 90 variants and the A4 series - and TT, A3 as well presumably)
C_ for large cars (The 100, 200 and A6 variants)
D_ for very large cars (The A8 is the only thing I can think of there)

B3 is the correct platform code for the 'Series 3 Coupe' like our S2 shaped machines - all those coupes are B3 platform, but its very common to see them described as 'Type 89' and we'll see why later on.
B4 is the platform code for the 4th generation of the Audi 80 - introduced in 1992 - All factory S2 Sedan and Avant are B4.

The main difference between B4 models is that not they have a different rear suspension layout - its a dual wishbone design (precursor to the B5 platform used for first A4 models) versus the Mcpherson strut at the rear of the B3 Coupe.

People often talk about the B4 bonnet being different - that is true for Sedan and Avant in comparison to the earlier 80/90 Sedan - but this is same bonnet on B3. Confused yet ?

The 'Typ' code is a different thing - this another set of model or type codes used to differentiate the models that share the same platform.

Here's a small selection of complete model codes from the B3 platform and you'll see that the 'Typ89' goes back to the first model designations from the B3 family when launched circa 1987. People also forget the 8A prefix was used on lots of these cars as well - seems people latch onto 'Typ89' as a way to describe all the B3 platform - which is not really correct.

894715 - 90 quattro saloon with KV engine 1987/88
8947T5 - 90 quattro saloon with 7A engine 1988/89
8A27T5 - 90 quattro saloon with 7A engine 1989/90
lots of other 8A saloons in Audi 80/90 designation from this B3 platform - there are no Avants with an '8A' prefix.


Then for Model Year 89 we start getting into the 8B model codes for the Coupes such as these...

8B30B5 - coupe quattro with NG engine 1988-90
8B3025 - S2 coupe quattro with 3B 1990-92
8B3039 - S2 coupe quattro with ABY 1992-96
Lots more 8B variants of course. See the confusing but total accidental use of B3 above within the '8B3' prefix there - you'd think its convenient, but its not. Here's why...



Then we have the 80 Cabrio models which also fall out of the B3 platform. Some of those as follows - none of em quattro of course !

8G70R4 - 80 Cabrio with AAH engine
Lots of 8G variants here... The B3 platform was in production then into 2000 long after the other 80 models were stopped.



Come 1992 (model year 1993) and the 'B4' platform is launched with the new facelift 80 model... Featuring the new bonnet style and improved front suspension (lifted from B3 Coupe). Also the utterly different rear suspension layout. There's a few other things like better crash protection and the introduction of diesel engines for the 1st time in the 80 family and some other styling tweaks like bumpers etc
Some notable members of the B4 family are then as follows -

8C57L9 - 80 quattro avant S2 with ABY
8C27L9 - 80 quattro sedan S2 with ABY
lots of other '8C' models which are both saloons and avants... 8C2 for saloon, 8C5 for avant

And for extra anorak points - the RS2 is not a B4 platform - it has the special designation of 'P1' and a model code of 8C57K9 - strange but true.

The UR quattro and its wedgy coupe cousins are 'Typ85' - whilst the same era 80 saloon is 'Typ81' - they are B2 platform.

The B1 platform would be the really early 80 models from the 70's and is just about irrelevant here....

So for B2 platform we essentially have the 'Typ85' coupe and 'Typ81' saloon (includes UR quattro of course).
And for the B3 platform we have 80 and 90 saloons in 'Typ89' and '8A' guise. The nomicker of 'Typ89' extends in the vernacular to the '8B' coupe models and '8G' cabrios... Enter the S2 Coupe
Then we have the B4 'facelift' platform on the last of line 80 models in saloon or avant guise. Here lies the S2 Avant and Sedan (and RS2 cousin from Stuttgart)

The B5 platform (if anyone still cares) was the first of the A4 branded models.

Still confused or does that make it better ?


Paul

[Flat on my back]

.

This is what i was planning...right now i have concerns over a small part used on the rear of the q drive cars that may cause big problems...Pete, i may need your car...

Converting a B4 chassis (saloon/avant) from fwd to q drive-can it be done?

I would like to discuss this subject from a technical point of view with evidence coming from ETKA and photos of people’s cars where possible. By all means the list below may not be complete…or quite accurate.

Physical differences between the cars: -

Engine bay.

1.sub frame,
2.

Floor pan.

1.propshaft,
2.exhaust,
3.fuel lines,
4.hand brake cable routing,
5.

Rear section.

1.rear suspension, sub frame, dampers,
2.brake line routing,
3.hand brake cable routing,
4.fuel tank, mounting,
5.exhaust,
6.

For each of the above differences I would like to gather information together to determine if it will be a ‘plug & play’ installation or if some amount of ‘cutting & shutting’ is required.

If you are able to assist, please do so but do make sure your posts add to the information e.g. pictures of the underside with a description of the cars age, type and engine.

At the moment I have a ’95 M plate 2.6 v6q saloon sat on my drive, unfortunately it is immobile so taking pictures of the underside is rather difficult, but I’ll do what I can.

[Skull]

flat: converting a b4 from fwd to q can be done, buy replacing the whole floor of the car. (From the gearbox ahead)

for your saloon, you can fit all REAR parts from avants or saloons quattro and all the front parts from b3 coupes and b4 avants/limos.

[spink]

[QUOTE=Skull23;385047]flat: converting a b4 from fwd to q can be done, buy replacing the whole floor of the car. (From the gearbox ahead)

QUOTE]

from what i have seen/heard recently certain 2wd B4 cars have all the mounting holes etc for the quattro drivetrain already in place,not sure which models they are on though.I think jas11n knows more about that.

[Acidburn]

http://www.audifans.net/modules.php?...ht=fwd+quattro

Quite a bit of info there.

[s2avant]

The platform codes are as follows -

A_ for small cars (The A2 for example is a model that also shares platform label)
B_ for medium cars (Like the 80, 90 variants and the A4 series - and TT, A3 as well presumably)
C_ for large cars (The 100, 200 and A6 variants)
D_ for very large cars (The A8 is the only thing I can think of there)

My turn to be pedantic The above should read:

AA for smallest cars (e.g A2, Polo, Ibiza, Fabia)
A_ for small cars (A3, TT, Golf, Leon, Octavia)
B_ for medium cars (Like the 80, 90 variants and the A4 series, Passat, Superb)
C_ for large cars (The 100, 200 and A6 variants)
D_ for very large cars (A8, Phaeton)

Back on topic slightly, the B4 FWD and Quattro models have the same floor pan. I looked at this a long time back when I was considering converting my TDi to Quattro. JasIIn and/or UR-S4 can back this up and they have both looked at the feasability of such a conversion.

Ben

[Jamo]

I can confirm Jas11n has looked into this and it's a goer but his concerns were reducing power the tdi engine when going to 4wd

[S2central.net]

OK - I bow to your greater inside knowledge - nice one Ben...

I was also skeptical about previous threads I'd seen about quattro running gear being able to be bolted into a FWD B4 chassis - thats a pretty bloomin impressive piece of generic / modular design - I didn't know that you and others had looked into it - that means its much easier for anyone to create an S2 Sedan out of any B4 chassis with the right donor parts... and equally importantly means that fewer V6 engined B4 quattros have to be sacrificed for the cause. With this new (well new to me) info I'd suggest its easier to start such an S2 sedan project from a 5-cyl B4 with FWD as the engine mounts will be correct - whereas they are wrong on the V6.

[S2central.net]

I suppose you could also cook up a V6 TDi conversion into a B4 quattro - with the right donor parts and a FWD chassis for starters... Or you could go quattro on the 19TDi variant - but that would need seriously upgrading take the extra weight penalty IMHO. Not easy / cheap projects - but eminently achievable if the chassis is generic and everything is bolt-on....