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I'm currently running a Griffin 1-26181-X (22x15.5x3) with a single 16in spal fan. I cut out the original radiator mount and fabricated my own to have it lean back at a 40 degree angle. A little more than half of the rad is wide open while the rest is tucked behind the bumper. I had overheating issues before I discovered my temp sensor wasn't turning the fan on. After fixing that, I've had no issues with temps. However the main reason mine is set up that way is the turbo sits directly in front of the gallardo exhaust manifold, right above/behind the radiator. If you are running a naturally aspirated setup or have a spa manifold I'm sure you have more room to play with, and most likely won't need to take such drastic measures.
Have you seen how Alan's radiator is setup? He is also running an aftermarket Griffin, however he has a different model that he converted to dual pass. IIRC theres a post or two about it in earlier pages, but also on Mike's youtube there's a video where he briefly discusses it. From the sticker on the bottom it looks like he has a 1-59201-X. It's a very short explanation, but should provide some insight. Start at 4:30 for radiator discussion. https://youtu.be/IdqtfvdwdAY?t=269
I'm sure there's more footage, but this is what I was able to find.
Very cool build!
Tilting the rad on my 944 was a mistake. I hope it works for you guys though! \
Best of luck.
Anyone know if a non reverse rotation turbo like the hx35 will fit in the 944 with the spa header? If someone could measure the distance from the spa header to the wheelwell/frame rail i could figure it out too.
If you tilt it, the air breather needs to be reworked, otherwise it will create air pockets.
That's good to know! Lucky for me when I took it apart it was only leaking from a cracked plastic drain plug. So the radiator change is going to get pushed down the road until I hit an even bigger rock . I just want to scrape by at least until this race season is over.
In my research on how to get the radiator out of harms way for rally I stumbled upon this picture of Orca that realy got me thinking...
I do need to replace my hatch too... but that should probably be it's own thread when the time comes
Royale,
That's a cool car.
In my struggle to improve cooling, the last mod I did was "tee" off the upper & lower rad hoses to use a Boxter middle rad plus the 944 n/a rad. It barely improved matters. But what I learned was there is a black art or science when it comes to heat exchangers. You can move the coolant too fast or too slow, and the Boxter is kind of the opposite of what you are proposing (heat exchanger & engine on opposite ends of the car). I was very surprised to see the Boxter hoses are like half the diameter of the 944.
Its possible tilting the rad is the best solution. My car had several things working against it, and its possible my T-stat was seized.
Not a black art - more surface area is always better. Only add thickness if you can't add surface area (and even then it is much less effective).
You can't move the coolant too fast - heat transfer equations are about flow rate and temperature difference inside/outside the exchanger. More of either makes more heat transfer overall.
Plenty of room on either side of the 944 rad (under the headlight areas) to put side radiators...or better yet, cut out the front sheet metal and put a real huge radiator in, versus the stock tiny baby MK1-Golf-size 944 rad.
And swap the 944 fans to a monster single junkyard OE fan.
Not a black art - more surface area is always better. Only add thickness if you can't add surface area (and even then it is much less effective).
You can't move the coolant too fast - heat transfer equations are about flow rate and temperature difference inside/outside the exchanger. More of either makes more heat transfer overall.
Plenty of room on either side of the 944 rad (under the headlight areas) to put side radiators...or better yet, cut out the front sheet metal and put a real huge radiator in, versus the stock tiny baby MK1-Golf-size 944 rad.
And swap the 944 fans to a monster single junkyard OE fan.
Agreed, also try keep the cool lines in cool air, so try not to run them behind radiators or near exhaust ect. You can also try ducting, with perfect ducting you can actually create a little bit of thrust while maximizing cooling, like the ww2 planes, but thats dang hard to achieve on anything thats not a plane or open wheel. The basic idea is to create an inlet roughly 80% the size of the radiator, have it expand to full size of the radiator amd have it smoothly neck back down to return back to the airstream behind the car. Well beyond our scope but interesting none the less, I learned this in a Carrol Smith book.
Agreed, also try keep the cool lines in cool air, so try not to run them behind radiators or near exhaust ect. You can also try ducting, with perfect ducting you can actually create a little bit of thrust while maximizing cooling, like the ww2 planes, but thats dang hard to achieve on anything thats not a plane or open wheel. The basic idea is to create an inlet roughly 80% the size of the radiator, have it expand to full size of the radiator amd have it smoothly neck back down to return back to the airstream behind the car. Well beyond our scope but interesting none the less, I learned this in a Carrol Smith book.
Sorry, to make the air work best, the thumb rule is 33% (1/3) duct size of the radiators core size, to slow the air speed thru the core.
Here's a good view of how much room is really available if you strip out all the stock heat exchangers from an early NA car. I'm keeping AC, so seen below is how I mounted my aftermarket condenser, and where the stock 07k crank pulley sits in respect to the chassis. I also drilled 4, 0.125" holes in the face of my thermostat, and installed a single high output fan from an Audi modified to fit the original radiator, and lemme tell you what she heats right up and stays right in the middle of the gauge when integrated with the stock thermo switch. For winter I'll probably change to a 2-hole t-stat because highway gets a little cool, but that's something I'm willing to live with given the nature of this build. The flow rate of fluid to exchange heat convectively through the metal with outside air is what's really important. Add as thick or as many rads as you want, this just works.
I took a bunch of pictures with my dslr, used software to put them all together and then smoothed it all out.... I don't have CMM/Faro arm access money like SOME people...( @vt951
Anyone know if a non reverse rotation turbo like the hx35 will fit in the 944 with the spa header? If someone could measure the distance from the spa header to the wheelwell/frame rail i could figure it out too.
thanks!
Can't speak for the HX35 but here is my standard rotation GTX3076R GEN II. Custom T3 to V-band adapter.
Thanks for the measurements they definitely help me out!
I have a few more questions, are you returning the oil feed from the turbo back into the oil pan or are you passing it through an oil cooler. I am pretty confused with how to plumb the oil cooler and the turbo. I know that I need to take oil off the head to feed the turbo and that the oilblock has an oil sending port but thats it.
Thanks for the measurements they definitely help me out!
I have a few more questions, are you returning the oil feed from the turbo back into the oil pan or are you passing it through an oil cooler. I am pretty confused with how to plumb the oil cooler and the turbo. I know that I need to take oil off the head to feed the turbo and that the oilblock has an oil sending port but thats it.
Directly back to the pan, there is a bung already welded on the upper Boost Brothers pan. You couldn't attach a cooler to the drain as it drains via gravity, there is no pressure. You could feed the turbo from the port on the head or the large oil port on the iABED block, it is right below the oil filter.
I suppose you could feed the oil cooler from the iABED block and then Y into the turbo oil drain for the return, I think most people are running a oil filter sandwich plate though.
I plan to feed the turbo from the head and run a remote oil filter block that has ports for a cooler with a built-in thermostat.
Very Interesting, out of curiosity why did you choose to go with the remote mount? Also what temperature should the thermostat be rated at?
For the Coolant setup, how did you go about it? Are you using any swirl pots or restrictors to build block pressure? Forgive my naïvety but does the pump on the side of the engine push the coolant into the block or suck it out of the engine and push it into the radiator?
06-22-2021, 09:14 AM
. I just want to scrape by at least until this race season is over.
