Anyone having cooling issues?

[robeyff]

I like your Christ, I do not like your Christians. Your Christians are so unlike your Christ. Mohandas Gandhi

You IDIOT. You can thank the tolerant nature of this board for putting up with your juvenile need to prove to yourself on a daily basis . . . whatever it is you need to prove.

There are umpteen extremely well educated and genteel members of this board who come here for the opportunity to relieve themselves of the stress and pretensions of their professional lives and communicate with their fellow E28 enthusiasts in the langauge of grease, beer, and down to earth conversation.

Tim in N FL is a world recognized psychologist, Duke has a couple of Masters in something or other, Tammer in Philly, Blue Shadow, Booker, Shawn D., myself, etc, etc all have professional degrees and expertise in their fields along with many others but manage to display their humanity on this board.

Give it a shot.

[GregATL]

When coolant exiting the radiator is too hot, the cylinder head temperature is bumped up a notch and, in a turbocharged engine that may be all that's required to push coolant temperatures high enough to allow film boiling of the coolant. When this occurs, thermal hysteresis resists the return to nucleate boiling. For what it’s worth, whenever a turbocharger is installed, the cooling, oiling, fuel, and ignition system should be blueprinted.

This is exactly why I have been looking for a higher capacity radiator. My safety margin is noticably reduced with the additional heat from the turbo system. I had already replaced every single component of the cooling system prior to the turbo install in an effort to make this a non issue. It's still an issue at this time.

Thanks for the detailed explanation. Makes perfect sense now.

[M635CSi]

I have a lot of respect for the efforts you make and some of the results you achieve. What pisses me off is that this was sooo predictable.

Well thank you sir. I sure wish that it as "sooo" predictable (to me). I would ditched the radiator in an instant if I really had suspected it.

Sometimes we can't read the label from inside the bottle. I was pretty upset when that thread was removed because I'd made an effort to contribute to what, I thought, would be your benefit.

The important thing is you've found a problem and are correcting it. The cooler you get that engine to run, the more power it can make.

For what it's worth, I fully expect your car to be running mid 11s in the 1/4 mile.

My door swings wide for you Duke so whatever I can do to help I'm available.

[chrism]

Idiot? Well thats neither educated nor genteel. Your not gonna be allowed to eat with the smart kids no more bitch!!

I like your Christ, I do not like your Christians. Your Christians are so unlike your Christ. Mohandas Gandhi

You IDIOT. You can thank the tolerant nature of this board for putting up with your juvenile need to prove to yourself on a daily basis . . . whatever it is you need to prove.

There are umpteen extremely well educated and genteel members of this board who come here for the opportunity to relieve themselves of the stress and pretensions of their professional lives and communicate with their fellow E28 enthusiasts in the langauge of grease, beer, and down to earth conversation.

Tim in N FL is a world recognized psychologist, Duke has a couple of Masters in something or other, Tammer in Philly, Blue Shadow, Booker, Shawn D., myself, etc, etc all have professional degrees and expertise in their fields along with many others but manage to display their humanity on this board.

Give it a shot.

[robeyff]

Idiot? Well thats neither educated nor genteel. Your not gonna be allowed to eat with the smart kids no more bitch!!

I like your Christ, I do not like your Christians. Your Christians are so unlike your Christ. Mohandas Gandhi

You IDIOT. You can thank the tolerant nature of this board for putting up with your juvenile need to prove to yourself on a daily basis . . . whatever it is you need to prove.

There are umpteen extremely well educated and genteel members of this board who come here for the opportunity to relieve themselves of the stress and pretensions of their professional lives and communicate with their fellow E28 enthusiasts in the langauge of grease, beer, and down to earth conversation.

Tim in N FL is a world recognized psychologist, Duke has a couple of Masters in something or other, Tammer in Philly, Blue Shadow, Booker, Shawn D., myself, etc, etc all have professional degrees and expertise in their fields along with many others but manage to display their humanity on this board.

Give it a shot.

Can't wait to meet you.

[Duke]

Can't wait to meet you.

I wish I could get my hands on a set of Pugil Sticks and associated safety equipment. I feel it would get a lot of use at 5er Fest this year

[robeyff]

Can't wait to meet you.

I wish I could get my hands on a set of Pugil Sticks and associated safety equipment. I feel it would get a lot of use at 5er Fest this year

Nah, he and I are too much alike; both suffering from occassional spasms of "verbatious dysenterius." No cure.

[Duke]

Heat Exchanger Placement UPDATE

I just pulled the front M-Tech valance/bumper. The second HE from the s2 kit is going to be mounted right behind the brake air duct on the passenger side. I may move the one behind the kidney gill to the driver side, same location. This will eliminate any heat from that HE passing into the radiator. The 11 X 11 HE is still going in the battery box. If all works out as planned, I will have 100% more HE capacity than the s2 kit came with instead of the 50% less right now. I'll take some pictures for the Fest because it will all be hidden by the M-Tech once that is reinstalled


.

[davidu]

heres a small pic were you can see my fan in front.This whole converstion set me back 35 bucks. And has 2 speeds. Does every post turn into a dik measuring contest with duke ,dang. I thought this is a cheap solution and fan is availible at any u-pull it yard cheap.Thermostat control switch ans 30 amp relays at auto zone.

[turbodan]

I have no issues with my m20 turbo. It got a new waterpump, hoses, t-stat, radiator and everything else when the engine was rebuilt for the turbo.

[Duke]

Heat Exchanger Placement UPDATE 2

Well the HEers will not mount to the body and fit behind the M-Tech front valance in front of the brake duct like I wanted. So I have done this, I am mounting the HEs to the valance itself. The top of the HE bolts to the top of the brake duct and the bottom on the HE to the bottom of the valance. The HE will be at a good angle but air will easily flow through them. The only huge PITA will be that I can not connect the coolant lines until the valance is just about mounted and will have to squeeze my fingers and screwdrivers between crack to tighten clamps.

The battery box is cut out and I have made a frame for the 11 X 11 HE out of drilled angle iron that will mount to the battery box walls. Need to make a hardware run and then do some painting.

I am happy to say that I will no longer have a HE in front of the radiator.

[Tammer in Philly]

Heat Exchanger Placement UPDATE 2

Well the HEers will not mount to the body and fit behind the M-Tech front valance in front of the brake duct like I wanted. So I have done this, I am mounting the HEs to the valance itself. The top of the HE bolts to the top of the brake duct and the bottom on the HE to the bottom of the valance. The HE will be at a good angle but air will easily flow through them. The only huge PITA will be that I can not connect the coolant lines until the valance is just about mounted and will have to squeeze my fingers and screwdrivers between crack to tighten clamps.

The battery box is cut out and I have made a frame for the 11 X 11 HE out of drilled angle iron that will mount to the battery box walls. Need to make a hardware run and then do some painting.

I am happy to say that I will no longer have a HE in front of the radiator.

That's cool, take a bunch of pics. Also, you should look into retaining some brake cooling. The way I imagine your setup looking, I'd bet you could pull a Naca duct off the belly pan behind the central area of the valance, then run 3" tube back to the brake backing plate area. Unless you never plan on stopping hard more than once in a row. ;-)

-tammer

[Boru]

Duke, attach the hoses to the heat exchangers first, leave extra hose and thread it into the engine bay as you slide the valance into place. This is what I did with the TCD E34 prototype.

[Duke]

I'd bet you could pull a Naca duct off the belly pan behind the central area of the valance, then run 3" tube back to the brake backing plate area.

Duke, attach the hoses to the heat exchangers first, leave extra hose and thread it into the engine bay as you slide the valance into place. This is what I did with the TCD E34 prototype.

Those are both great ideas. THANKS! I will incorporate both of them in the next three days. I took three days leave to get this done right the first time.

Then again, as far a braking, I could alway install the "turbine" covers I have saved.............shutter............................chill goes up my spine....................shutter again.

[Skeen]

Duke, you won't need brake cooling. Spend your time on something else.

[Duke]

Duke, you won't need brake cooling. Spend your time on something else.

Yea, I agree. I have the E31 840Ci 4-pot Brembos with 324 X 30MM rotors up front. It will take a lot of scrubbing to get them hot.

[Tammer in Philly]

I'd bet you could pull a Naca duct off the belly pan behind the central area of the valance, then run 3" tube back to the brake backing plate area.

Duke, attach the hoses to the heat exchangers first, leave extra hose and thread it into the engine bay as you slide the valance into place. This is what I did with the TCD E34 prototype.

Those are both great ideas. THANKS! I will incorporate both of them in the next three days. I took three days leave to get this done right the first time.

Then again, as far a braking, I could alway install the "turbine" covers I have saved.............shutter............................chill goes up my spine....................shutter again.

Oh yeah--I forgot you have the throwing stars. Those covers you run actually work equivalent to the turbines in terms of air extraction, so you should be good.

-tammer

[Maddog]

As far as an upgraded radiator goes, I don't think we have broken any ground.

Mike, wasn't your car fine cruising around but running hot on the track?

[GregATL]

As far as an upgraded radiator goes, I don't think we have broken any ground.

You're right there. Still in the planning stages.

[90e34535i]

Under boost, My Coolant Temp never goes up more than maybe, 3-4 degrees(though usually just 1-2 deg), and then drops back down those several degrees once im off boost.

Never noticed any over heating issues since boosted.

[vance]

Under boost, My Coolant Temp never goes up more than maybe, 3-4 degrees(though usually just 1-2 deg), and then drops back down those several degrees once im off boost.

Never noticed any over heating issues since boosted.

I wonder how much more cooling capacity the e34 has over the e28?

Vance

[Skeen]

Mike, wasn't your car fine cruising around but running hot on the track?

Right. And hot in traffic.

Under boost, My Coolant Temp never goes up more than maybe, 3-4 degrees(though usually just 1-2 deg), and then drops back down those several degrees once im off boost.

Mine does the same thing. It doesn't overheat under boost (unless in track conditions where it's constantly under boost). The problem is really just slow speed stuff.

[Duke]

A quick note for all my FI friends. The stock M30 US spec cars (186 hp) came with a 13 psi "radiator" cap. My M535i (218 hp) came with a 14.5 PSI cap. The Euro Spec E28 M5 (286 HP) has a 1.4 bar (20 psi ) cap.

UPDATE - the S38 3.8 (340 HP ) has a 2 bar (30 psi!) cap.


Why would we FI guys with easily over 300 HP have a 13 psi cap installed? I think I have found a big reason for cooling issues with FI M30s.

[vance]

You could definitly be on to something Duke. For the 745 it's 1.4 bar and for the Saudi version it's 1.5 bar.

Vance

[Duke]

I installed a 20 psi cap this afternoon. The temp stayed between 170-180 on the drive home (with boost now and then) and got up to 190 in stop and go traffic. Air temp was 79 F.

Looking goooooooooooooooooood.

The hoses are hard as hell and I would not attempt to crack the cap until the engine is fully cool. The coolant temp was at 180 when I shut it off. Make sure you have healthy hoses before doing this.

Will let you know when the air temp is in the 90s and I am running the A/C.

[90e34535i]

According to RealOem (dot) com , the e34 535i has a 2.0 Bar Cap. It doesnt list the e28, but it says US e30 325i's use a 1.4 Bar cap.

[Duke]

According to RealOem (dot) com , the e34 535i has a 2.0 Bar Cap. It doesnt list the e28, but it says US e30 325i's use a 1.4 Bar cap.

To be more clear - thats an E34 535i with a M30 engine. 30 psi cap

Temp did not pass 180 on the drive into work this morning (25 miles). Lots of boost (10-11 psi)

[Duke]

UPDATE

Have had the 20 lb cap on for several days now. The car runs at around 170-180 in moving conditions. Stop and go, 190. A couple of times it got up to 200. Boost has not had a effect on the temp up to this point.

Am very happy with the 20 lb cap. Cost $8 at Advanced Auto.

[Skeen]

UPDATE

Have had the 20 lb cap on for several days now. The car runs at around 170-180 in moving conditions. Stop and go, 190. A couple of times it got up to 200. Boost has not had a effect on the temp up to this point.

Am very happy with the 20 lb cap. Cost $8 at Advanced Auto.

What's ambient? That sounds about like my car now on 85F days.

[canyoncarver]

there really is a quick fix to these heating issues.........

the factory 524TD radiator is substantially thicker than our 533/535 units and will essentially fit with minor mods.

1. due to clearance issues, the side tanks need to be swapped from side to side and the core flipped 180 degrees.
2. the rubber locating mounts on the radiator support need to be moved to the aft most positions ( the holes are already drilled)
3. you must use an e23 top hose.
4. used with the e32 water pump pulley and a 71C thermostat youll see a huuuuuuuuuuuuuuuuge reduction in idle temps.

this is of course assuming all other cooling components are in top shape.

these mods have served me well running an 11-1 NA motor with the a/c on while stuck in commuter traffic during some of so-cals recent 100 degree plus days