Re: Water to air intercoolers

TheEngineer wrote:

For the record I do appreciate suggestions, even if it doesn't sound like it. I'm just frustrated with this issue and tired of chasing it.

Well, you could solve it Saab-style:

https://en.wikipedia.org/wiki/Next_gene … ank_Weapon
https://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Pansarv%C3%A4rnsrobot_57_aka_MTB_LAW.jpg/300px-Pansarv%C3%A4rnsrobot_57_aka_MTB_LAW.jpg

Re: Water to air intercoolers

Maybe I'm missing something with the fans.  It's my understanding that the fans are useless while the car is moving?  So bigger fans wouldn't change your overheating issue?  I agree with tilting the radiator/moving it forward/improving in-out airflow, or just get a larger or second radiator.

"We Got Screwed" NHMS 2017, 4th NHMS 2020,  4th NJMP 2021,
"Judges Choice" NHMS 2021,10th NJMP 2022, 3rd Thompson 2022
#847 Batmobile  aka-"Beulah"  search Squidrope Racing on Facebook

28 (edited by chaase 2022-04-06 05:46 PM)

Re: Water to air intercoolers

squidrope wrote:

Maybe I'm missing something with the fans.  It's my understanding that the fans are useless while the car is moving?  So bigger fans wouldn't change your overheating issue?  I agree with tilting the radiator/moving it forward/improving in-out airflow, or just get a larger or second radiator.

The movement of air at speed is enough to not require the fans to turn on for many cars. However, If the coolant temp gets too high, the fans will turn on and function. As far as I know they still help cool the car down. It is one of the reasons that cars will almost always command the fans on when the A/C is turned on.

1992 Saturn SL2 (retired) - Elmo's Revenge -  Class B winner, Heroic Fix winner x2
1969 Rover P6B 3500S(sold) - Super G-Rover - I.O.E Winner, Class C Winner
1996 Saturn SW2 - Elmo's Revenge (reborn!), Saturn SL1  Dazzleshipm Class C x2 and IOE winner
1974 AMC Javelin - Oscar's Trash heap - IOE,”Organizer's Choice" and "I got Screwed" award winner

Re: Water to air intercoolers

chaase wrote:
squidrope wrote:

Maybe I'm missing something with the fans.  It's my understanding that the fans are useless while the car is moving?  So bigger fans wouldn't change your overheating issue?  I agree with tilting the radiator/moving it forward/improving in-out airflow, or just get a larger or second radiator.

The movement of air at speed is enough to not require the fans to turn on for many cars. However, If the coolant temp gets too high, the fans will turn on and function. As far as I know they still help cool the car down. It is one of the reasons that cars will almost always command the fans on when the A/C is turned on.

I understand that the fans will come on if the thermostat tells them to do so.  But that doesn't mean that they are helping cool things if the car is moving at speed.  A/C is in street car with stop and go conditions.  It doesn't seem reasonable that any fan will produce the same amount of air volume as a 60+ mph breeze?

"We Got Screwed" NHMS 2017, 4th NHMS 2020,  4th NJMP 2021,
"Judges Choice" NHMS 2021,10th NJMP 2022, 3rd Thompson 2022
#847 Batmobile  aka-"Beulah"  search Squidrope Racing on Facebook

Re: Water to air intercoolers

squidrope wrote:

Maybe I'm missing something with the fans.  It's my understanding that the fans are useless while the car is moving?  So bigger fans wouldn't change your overheating issue?  I agree with tilting the radiator/moving it forward/improving in-out airflow, or just get a larger or second radiator.


Fans do absolutely work at speed, the problem is most electric fans do not flow enough cfm to make a difference at speed.

The mechanical fan on my semi truck comes on at 207 degrees and will drop the coolant temp down to 170 in a hurry.  This happens at 15 mph or 75 mph it doesnt matter.   I can be pulling 250,000lbs up a 5% grade at 30 psi of boost, it doesnt matter.  The sheer amount of cfm it flows over the radiator is enough to cool it down.   I have an intercooler, ac condensor,  radiator, metal screen, and a metal grill all stacked together.     The downside is that it takes a bit of HP to spin a mechanical fan.   


Better fans, and ducting are the answer to cooling issues.   A bigger radiator only gets you so far.

Re: Water to air intercoolers

hkerekes wrote:
squidrope wrote:

Maybe I'm missing something with the fans.  It's my understanding that the fans are useless while the car is moving?  So bigger fans wouldn't change your overheating issue?  I agree with tilting the radiator/moving it forward/improving in-out airflow, or just get a larger or second radiator.


Fans do absolutely work at speed, the problem is most electric fans do not flow enough cfm to make a difference at speed.

The mechanical fan on my semi truck comes on at 207 degrees and will drop the coolant temp down to 170 in a hurry.  This happens at 15 mph or 75 mph it doesnt matter.   I can be pulling 250,000lbs up a 5% grade at 30 psi of boost, it doesnt matter.  The sheer amount of cfm it flows over the radiator is enough to cool it down.   I have an intercooler, ac condensor,  radiator, metal screen, and a metal grill all stacked together.     The downside is that it takes a bit of HP to spin a mechanical fan.   


Better fans, and ducting are the answer to cooling issues.   A bigger radiator only gets you so far.

I don't know if its available for the Saab but we also run higher pressure radiator caps when possible. It raises the boiling point of water even higher.in case things really start to heat up.

1992 Saturn SL2 (retired) - Elmo's Revenge -  Class B winner, Heroic Fix winner x2
1969 Rover P6B 3500S(sold) - Super G-Rover - I.O.E Winner, Class C Winner
1996 Saturn SW2 - Elmo's Revenge (reborn!), Saturn SL1  Dazzleshipm Class C x2 and IOE winner
1974 AMC Javelin - Oscar's Trash heap - IOE,”Organizer's Choice" and "I got Screwed" award winner

Re: Water to air intercoolers

It's true that fans will not move as much as as you can get just with a car moving (generalized statement). But there are still reasons to have them.

Fans can help move the air once it's through the radiator (if things are setup right). You can have all the air in the world coming to the front of the radiator, but if it can't go anywhere in the engine bay, doesn't do any good. Depending on your setup fans can help ensure air keeps moving in the engine bay.

Also, in traffic you may be getting reduced or no airflow. Sitting on someone's bumper means you aren't getting the same forced air levels, so fans help even those changes out.

This is also why people argue for and against fan shrouds. Shrouds ensure a fan is only pulling through the fan, not just recirculating nearby air. But they also close off paths that air can take once you get into that region where airflow through the bumper is greater than fan flow. There are one way flaps you can add to a shroud, but they are often small.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Water to air intercoolers

Well I've convinced myself to skip the water to air for now, though the idea is not out of my head.

Did some front end massaging, looks like I can indeed tip the radiator ~10-15°, which opens up a ton more room for fans and exit ducting. Just need to build the new brackets. With that I'll do all new front end ducting.

https://i.imgur.com/ghnBKgH.jpg

Ignore the wiring mess, I'm in the middle of redoing it all, haven't torn out that bunch.
https://i.imgur.com/eAYBWru.jpg

We need a new intercooler no matter what because we found an end tank blown off. No idea when that happened, car was making normal boost when the clutch came through the bellhousing. I also need a new oil cooler. The old RX7 one we're using is starting to shed fins as the aluminum deteriorates. So I think the new plan will be to punch out the closed areas of honeycomb in the bumper, situate an oil cooler on one side, intercooler on the other, and then leave the main center openings to feed just the radiator, all with the right ducting inside.

https://scontent-bos3-1.xx.fbcdn.net/v/t31.18172-8/22712454_1028208900654340_1253478393756115135_o.jpg?_nc_cat=110&ccb=1-5&_nc_sid=09cbfe&_nc_ohc=-fP6ibRb1EwAX_XBEUA&tn=UpUsNEaLEWTZWA40&_nc_ht=scontent-bos3-1.xx&oh=00_AT9IDrQg9Rlg3eOiNydSjiOs6HmkiE25qxsmOHilKhPOmg&oe=627845CE

That splitter hasn't been on the car since the year or so, though I'd like to put a new one on to grab more air through the lower opening.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Water to air intercoolers

It sounds as though you are having the exact same problems we were having with the Merkur.
4-cylinder with turbo, or 302 V8 gave us over-heating trouble. We went through all of the same
solutions you have implemented, and also added a 2-pass radiator to the V8,but we still
ended-up driving to the coolant temps.

OK, I may have missed it, but from the photo it looks like the car is also street-driven.
It wasn't until I cut two 4x12 inch holes in the bumper cover that we solved the problem.
Our temps went from 230°F to 180°F under all but the hottest conditions. We now peak
at around 205°F at the hottest.

Looking at your bumper beam, I'd say the replacing the beam with tubing will clear out some
space for air flow, and opening the bumper cover up for additional air intake will solve the problem.
Though, this may not be the answer you're looking for.

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Water to air intercoolers

Car is no longer street driven. It was a daily driver before being turned into a race car, but no longer. That picture was just the easiest one I could find of the front bumper showing the OEM openings.

Opening up the cross bar and bumper more is totally an option. I had thought more about just modifying the plastic bumper cover, but i would not be opposed to cutting some round holes in the metal bar and then tacking in some round tube to keep the strength up.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Water to air intercoolers

If you can afford a test day, open up the bumper cover,
or even run without it and see what your temps run.
I'd run with the fat factory beam, and w/o it, as well.
Maybe wait on cutting the bumper cover until you know
it would make a difference.

We were trying a bunch of different strategies, and carving
out the new holes with a utility knife in the pits was sort of
a last ditch effort. I thought we had enough opening
already with the upper and lowers we already had,
but clearly it wasn't enough. We had air guides, puller
and pusher fans, hood vents, etc. None of it was enough,
because they just couldn't get enough access to the air needed
for cooling.

The 2-pass radiator fixed the problem in my previous
car, but not this one. Now a single pass radiator in this car could
still have problems in the current configuration, but I'm not going to
mess with success unless I absolutely have to to find out.

I'll get a pic tomorrow of our bumper cover and post it.

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Water to air intercoolers

That's a good start!

1992 Saturn SL2 (retired) - Elmo's Revenge -  Class B winner, Heroic Fix winner x2
1969 Rover P6B 3500S(sold) - Super G-Rover - I.O.E Winner, Class C Winner
1996 Saturn SW2 - Elmo's Revenge (reborn!), Saturn SL1  Dazzleshipm Class C x2 and IOE winner
1974 AMC Javelin - Oscar's Trash heap - IOE,”Organizer's Choice" and "I got Screwed" award winner

Re: Water to air intercoolers

The upper opening in the fascia, and lower opening in the center of the bumper cover
had seemed like they should be sufficient, especially with all of the other mods in place.
They were not. We even removed all of the wire mesh screens thinking that they were limiting
air flow too much. NOPE.

Only when I cut the new openings in the bumper cover did the temps drop to where they
are today. (I cut them free-hand with a utility knife, so they're a bit wobbly.)


https://i.imgur.com/VDcfu5g.jpg

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Water to air intercoolers

That wide bumper beam isnt helping.   A single 1 7/8 roll bar tubing bent to the bumper curvature will flow more than some holes and be as strong as the oe beam.    It will probably weigh less as well.    You can also gain a lot more real estate infront of the radiator with  tubing vs the oe crash beam.

Re: Water to air intercoolers

I took a closer look at the bumper beam last night. The stupid thing does not unbolt, it's part of the integrated crash structure all the way back to the frame rails. Never seen one that can't be unbolted. I think I'm going to go the route of punching a bunch of ~2" holes in it, then welding in 2" tubing to help keep the air moving straight through without doing weird things in the beam cavity. Then match those holes in the bumper cover.

Also will gut the grill material so it's less obstructed.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Water to air intercoolers

TheEngineer wrote:

I took a closer look at the bumper beam last night. The stupid thing does not unbolt, it's part of the integrated crash structure all the way back to the frame rails. Never seen one that can't be unbolted. I think I'm going to go the route of punching a bunch of ~2" holes in it, then welding in 2" tubing to help keep the air moving straight through without doing weird things in the beam cavity. Then match those holes in the bumper cover.

Also will gut the grill material so it's less obstructed.

You are not supposed to alter the crash structure so be careful removing things.

1992 Saturn SL2 (retired) - Elmo's Revenge -  Class B winner, Heroic Fix winner x2
1969 Rover P6B 3500S(sold) - Super G-Rover - I.O.E Winner, Class C Winner
1996 Saturn SW2 - Elmo's Revenge (reborn!), Saturn SL1  Dazzleshipm Class C x2 and IOE winner
1974 AMC Javelin - Oscar's Trash heap - IOE,”Organizer's Choice" and "I got Screwed" award winner

Re: Water to air intercoolers

At this point, what I would seriously consider doing, is to cut the bumper beam
and leave the crush structure alone. The crush box is the box in the image that has
the line labeled "3"  cutting across it. That is NOT supposed to be welded on, except with
bronze MIG wire.

The bumper beam can be welded on with normal MIG welding processes. I'd cut the beam
away between frame rails/crash boxes and replace it with tubing bent to sit just behind the
bumper cover. That is A LOT easier than cutting and filling holes in the beam, especially
since you cannot simply unbolt the structure to work on it.
Just my 2¢. Pic and info comes from AllData.


https://i.imgur.com/FGMPCm7.png

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Water to air intercoolers

I am not touching anything that is or could be considered crumple zone. not worth it. Not worth it to me to even cut off the OEM beam to replace it. I don't need the questions about if I cut in the right place to avoid altering the crash structure.

I've asked HQ/Tech about holes in the OEM beam before and been told that's fine. For me, I'm fine taking the time to hole saw some holes and tack in some tube. At least I know the bumper cover will stay in place with that setup.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice