expansion tank routing and location

[luis.e30325es]

So i am at that point on my swap, i have an 87 325es, and ive looked online it seems that newer e30's have different brackets for expansion tanks, to me it seems like it i might be wrong.
id like to know how people routed their expansion hose and tank with their m5X swap, depending if they used that kind of radiator.
pictures or descriptions welcomed, thanks for the help.
also: for my temp sensor on radiator, do i need to use the e30 one? or m50 one? i know i need to use temp sensor from e30 on my head. just thought id ask.
thanks guys

[EduardoGomez]

Hey luis why don't you post this in AZBMW.org forums? Those guys would help you.

I know, I know, no quality people there thats why you come here to get some quality response.

pre -87 has an expansion tank on the rights side wheel well, and on 88+ it is on the left side wheel well. Totally different.

In your case I would use 92-95 318i radiator, then you don't have to worry about expansion tank location. Use E30 temp sensors.

[luis.e30325es]

Hey luis why don't you post this in AZBMW.org forums? Those guys would help you.

I know, I know, no quality people there thats why you come here to get some quality response.

pre -87 has an expansion tank on the rights side wheel well, and on 88+ it is on the left side wheel well. Totally different.

In your case I would use 92-95 318i radiator, then you don't have to worry about expansion tank location. Use E30 temp sensors.

hey man, those people on that forum are a group of good guys, that goes for those who dont act like douche bags and talk crap about everyone.
and i am going to take this as an insult towards them, so back off.
azbmw is a different forum then this, sure i can find more technical help on here, r3v is a great technical forum, but azbmw unites bmw enthusiast in az by doing local meets and stuff like that and when i need help i know who to go to. just the fact that noone likes u there means u can come to a different forum and talk crap about them on here.
i mean why not say it on there? afraid of the insults or what?
u should just might as well delete your account from azbmw..that is if your not banned before you get to do it.

[Jalves619]

Hey now Don't hate


Anyways what our good friend HakenTT said is correct. Early cars use a tank on the passenger side wheel well, while late(88+) have it on the driver side. Many people choose to use a 318is m42 radiator to clean up the bay and simplify hose routing. Match the way the m20 hoses are routed with whichever coolant tank you use. As far as radiator sensors, I would say the majority opt for a lower temp thermoswitch whose part number I don't have on hand, but is all over the forums. See Azbmw people can be helpful.

Edit: 61-31-8-361-787 Is the 80c/88c high low rad switch.

[M-technik-3]

Or you could purchase an E30 M3 expansion tank, it mounts on what was originally the Battery tray.

[luis.e30325es]

Hey now Don't hate


Anyways what our good friend HakenTT said is correct. Early cars use a tank on the passenger side wheel well, while late(88+) have it on the driver side. Many people choose to use a 318is m42 radiator to clean up the bay and simplify hose routing. Match the way the m20 hoses are routed with whichever coolant tank you use. As far as radiator sensors, I would say the majority opt for a lower temp thermoswitch whose part number I don't have on hand, but is all over the forums. See Azbmw people can be helpful.

Edit: 61-31-8-361-787 Is the 80c/88c high low rad switch.

he is correct, but the rest of his response was unnecessary, frankly im getting tired of his crap.
yeah, i would like to go with that radiator, but i already have a late model e30 one, so i have to use the expansion tank.
could the cruise control get mounted on the side of the tank if i choose to move it over and mount the tank on the driver side?
thanks man

[luis.e30325es]

Or you could purchase an E30 M3 expansion tank, it mounts on what was originally the Battery tray.

yeah i saw those, just that i already have one, not looking forward on waiting for shipping and paying for another.
that wouldnt interfere with the m3 wiring cover?

[M-technik-3]

No since both are on M3. The M20 torpedo mount is slightly different and you could make a mount for it on the tray. The M42 radiators are ok but tend to crack where the plastic meets the aluminum.

They are in expensive but don't mount directly into early chassis cars. Check Janderson build thread he has an old E swap to 24V and fabbed a mount for his radiator.

[luis.e30325es]

oh ok. ill make sure i take care of that issue.
whats his user name?

[Hobbes]

There is a reason BMW engineers chose to give thier 6 cyl cars bigger radiators than the 4 cyls. The m42 one will work, but I wouldn't do it unless you have no other choice.

You can modify the expansion tank to fit flush against the drivers side wheel well and then put some hardware going into the wheel well. Or, make a bracket and mount it off of the stock airbox tabs. I would run a late model m20 expansion tank and either an e36 aluminum radiator or a late model m20 radiator. M42 radiators are garbage and you are downsizing your radiator, which is a dumb decision in the first place.

oh, and you can use either the e36 expansion tank hose or the e30 expansion tank hose. They are close in shape and size, but one (i cant remember which) has an extra hose off of it that has something to do with throttle body heating. They are also both pretty expensive as far as heater hoses go.

[luis.e30325es]

There is a reason BMW engineers chose to give thier 6 cyl cars bigger radiators than the 4 cyls. The m42 one will work, but I wouldn't do it unless you have no other choice.

You can modify the expansion tank to fit flush against the drivers side wheel well and then put some hardware going into the wheel well. Or, make a bracket and mount it off of the stock airbox tabs. I would run a late model m20 expansion tank and either an e36 aluminum radiator or a late model m20 radiator. M42 radiators are garbage and you are downsizing your radiator, which is a dumb decision in the first place.

oh, and you can use either the e36 expansion tank hose or the e30 expansion tank hose. They are close in shape and size, but one (i cant remember which) has an extra hose off of it that has something to do with throttle body heating. They are also both pretty expensive as far as heater hoses go.

yeah thats what i have, the e36 one with square expansion tank.
and about that extra hose, i figured out how to by-pass it thanks to help of some guys on here.

what kind of setup do you have?