Bmw m30 b35 accessories fitment and belts swap questions

[bavarian]

Hey so I’m currently building a b35 for my e12 , these questions are more about the old m30 so it should be very similar to the one of the e9. I am keeping the motronic 1.3 intake

#1 can the b35 powersteering pump be used to power the old style racks and which way would you go old or new?
Can the old powersteering bracket be bolted to the b35 block , if you go old power steering pump should you go with an old style water pump pulley will the belts line up?


#2 I have the early style oil pan and the early style pick up tube , the early style pick up tube bolts up to the main cap for support in the old engines but there’s no spot for it to bolt up in the newer m30s, do people leave it just bolted to the oil pump with no support , I do have the top old style main cap and longer bolts for the base in which the old pick up bolts too I could adapt it but I won’t unless recommended,


#3 has anyone gone with an e34 new or rebuilt ac compressor instead of the sandem , it seems available for not too much ?

#4 for the people who have to 1.3 motronic where did you hide the computer the harness seems a lot shorter

#5 would the Ireland engineering crank oil scraper work on a b35 with the old school pump pick up

 

[HB Chris]

1. Use b30 pump and bracket, bolts on fine
2. IDK
3. Sandens are cheap, use one of them, the Bosch Seiko is OK though
4. above glove box, make a small bracket, 2 1/8 hole if I recall. I mounted power junction and ecu and fuel relays there too on a bracket on the side panel with JBWeld
5. Why?

 

[bavarian]

1. Use b30 pump and bracket, bolts on fine
2. IDK
3. Sandens are cheap, use one of them, the Bosch Seiko is OK though
4. above glove box, make a small bracket, 2 1/8 hole if I recall. I mounted power junction and ecu and fuel relays there too on a bracket on the side panel with JBWeld
5. Why?

hey thanks
1 i wonder if the belt would be different for the old power steering pump with he new crank pulley of the b35 ?
3 did you have to make custom ac lines
5 scraping oil off the crank is said to free a little horse power

 

[Ian C]

2. The later pump pickup is a lot shorter than the early version, and the factory supported it for a reason I'd guess. Given the bracket that supports it is a separate piece from the main cap, you'd only need the longer bolts to add it.

 

[wkohler]

No problem with removing a couple main cap bolts and adding the later oil pump pickup bracket (the stamped steel one) or the longer bolts and the cast bracket from the early motor. Just make sure they’re torqued properly of course.

Rebuilt compressors are junk. There are no parts to rebuild the Seikos and most of the rebuilt Behr leak at the front seal within a couple months. Also, I’ve had very bad experiences with rebuilds offered on the Behr compressors. Go with a genuine Sanden 508. Use the stock bracket on the B35 and add one of the Sanden adapter brackets to it. Gives a lot of adjustment and works with a 13x875 belt which is a stock Porsche size so easy to get.

You can get a crank scraper that will fit but it becomes your oil pan gasket, you have to destroy part of the factory windage tray to make it fit and also can potentially lead to issues with the middle 2 rods getting hot.

Use your stock accessory brackets for the E12 to simplify things. You could use M30B34 brackets and take advantage of a solid mount 90a alternator. The lower accessory bracket for the B35 is part of the oil pan so that’s not going to work. You probably could adapt the later pump. It’s really just fittings. Any pressure differential wouldn’t be high enough to make a difference. The car has a steering box not a rack. They used that aluminum pump from 1983 through the E36 and you can even buy a new Meyle that puts out 120 bar. Keep the smaller pulley for the water pump. Your power steering pump and the AC compressor should be driven off front of the crankshaft (AC in front, then power steering then the alternator and water pump on the same belt in the back).

You’re going to have to convert to a throttle cable to run the engine with the stock intake manifold. I suggest you look at what they did on the 9/80-8/82 Euro E24s that ran motronic. They had cable actuated throttle versus the linkage rods and bell crank all while using the early pedal bracket.

You’ll need to adapt the right side motor mount. Koala Motorsport sells the adapter for that. Others may as well by now, it’s not complicated.

 

[Ohmess]

1. I think there are three m30 power steering pump belts for the e9s. The earliest belts were designed to run off of the 134mm water pump and cooling fan pulley (with the 138mm vibration dampener pulley). Power steering belts were 9.5mm x 1125mm.

BMW changed both pulleys somewhere along the line to improve engine cooling. The power steering pump belt would be 9.5mm x 1075 with the modified smaller 102mm water pump and cooling fan pulley (which mates with a 162mm vibration dampener pulley).

The third setup runs the power steering pump off of the vibration dampener pully and has a three row pulley. (I don't have a dimensional measurement for this, but it is pretty easy to distintguish either of the two groove pulleys from the three groove pulley.) I changed to this setup in my car last year. The brackets for this setup show up in my e3/e9 parts books, so I believe this was the last iteration of the power steering pump installation in the e9s, and then would be the setup in an e12.

I don't have a BMW part number or BMW spec for the belt, but I'm using a Gates 7350 - 10mm x 904mm.

 

[HB Chris]

Yes the belt is a different size as stated above and no I did not have to move the two a/c pipes. The ecu sits higher than that and can’t be seen unless you look up at it.