Hi All

I am in the process of upgrading an '85 Auto Euro 16V to the brembo brakes carried by the '86 Euro.

I have come across a couple of problems:
1. the 85 uses the older round connectors for the ABS sensor, whereas the 86 uses the more modern oval type (aka S4 type)
2. the ABS coding wheels on the 85 have a very fine pitsch when compared to the 86.

Is it ok just to splice the wiring on the '86 hubs thus transferring the correct connector for the '85?

Will the ABS control unit be Ok with the signals coming from the later type ABS coding wheels from the '86? I will be changing all 4 hubs so the '85 will be going from fine pitch alround to corse pitch alround?

 

John, I'm going to refrain from answering your quesions because I don't remember the answers, however I recall you may need to do more than you are suggesting. If you search the forums, there have been many instances where owners have done this job.Suffice it to say the pickup (brain) needs to expect the hub it is seeing.

 

ABS box will think car is traveling 1/2 speed if you do not swap coding wheels. This could affect how much it will apply pressure in different speeds and maybe cause problems. I would change them to fine pitch versions. It should be doable and I think only front hub is affected as rear is part of drive shaft anyway.

Is resistance for example same in old and new style sensors? If its not it can mean they are not similar parts internally. This could mean old style box can't understand new style signal anyway even if 1/2 frequency signal greated by fine pitch wheel would work from fequence point of view. There might be some help in Jim Morehouse CD's ABS and yearly changes documents. Also does ABS control box have different part number for '85 and '86 MY?

 

Erkka

Many thanks for those pointers, I will check the sensor resistances, and compare ABS control box part numbers with my '86 Euro.

Good point on the half road speed issue with the corse ABS coding ring.

Do you know whether the coding rings can be changed on the front hubs? Are they just a push fit?

I think, although I haven't checked, that the front wheel bearings are different on the '85 and '86, so I might not be able to swap the '85 hub/coding wheel onto the '86 hub carrier which i need for the brembo brake mounting.

John

 

They should be changable and have just push fit IIRR. Someone here looked into it while back.

 

I am swapping a US 86.5 on to a US 86 and face similar issues. Is it possible? I have an entire 86.5 donor car to get the required parts off of.

 

You can swap the connectors. It will have zero affect on system performance. However, you will need to retain the 85 tone wheels. If not, the system WILL NOT work correctly and can become dangerous.

 

What if I splice the 86.5 connectors and swap in the ABS brain? The actual pump is the same, right?

The only issue is the '85 tone wheels' on the rear axles, right?

 

I'm not sure if the pumps are identical. There could be different orifices inside it. I would keep one system, or the other. Splicing two together could lead to bad things.

 

I looked at the PET and it looks like the part numbers are the same. The brains are different as are the connectors and wiring. But I agree about picking one year or the other.