Oil cooling for GT - what to reinstate
#1
Burning Brakes
Thread Starter
Oil cooling for GT - what to reinstate
Morning all
So I have been going through cooling system, fans off for overhaul, radiator removed etc. The radiator is leaking so will be replaced but I have noticed that the oil cooler has been bypassed. Someone has linked the inlet outlet on the block with hose, I suspect because the cooler has failed at some time. I think I am right in saying the GT had a long thin oil cooler under the radiator? - if so mine is missing, therefore radiator with no side tanks (as a manual car and no trans cooler?). Question is given parts availability/cost/performance would you try to put everything back as stock or would you recommend a rad with the built in cooler tank, or rad with no tanks and aftermarket oil cooler?
D
So I have been going through cooling system, fans off for overhaul, radiator removed etc. The radiator is leaking so will be replaced but I have noticed that the oil cooler has been bypassed. Someone has linked the inlet outlet on the block with hose, I suspect because the cooler has failed at some time. I think I am right in saying the GT had a long thin oil cooler under the radiator? - if so mine is missing, therefore radiator with no side tanks (as a manual car and no trans cooler?). Question is given parts availability/cost/performance would you try to put everything back as stock or would you recommend a rad with the built in cooler tank, or rad with no tanks and aftermarket oil cooler?
D
#2
Rennlist Member
Morning all
So I have been going through cooling system, fans off for overhaul, radiator removed etc. The radiator is leaking so will be replaced but I have noticed that the oil cooler has been bypassed. Someone has linked the inlet outlet on the block with hose, I suspect because the cooler has failed at some time. I think I am right in saying the GT had a long thin oil cooler under the radiator? - if so mine is missing, therefore radiator with no side tanks (as a manual car and no trans cooler?). Question is given parts availability/cost/performance would you try to put everything back as stock or would you recommend a rad with the built in cooler tank, or rad with no tanks and aftermarket oil cooler?
D
So I have been going through cooling system, fans off for overhaul, radiator removed etc. The radiator is leaking so will be replaced but I have noticed that the oil cooler has been bypassed. Someone has linked the inlet outlet on the block with hose, I suspect because the cooler has failed at some time. I think I am right in saying the GT had a long thin oil cooler under the radiator? - if so mine is missing, therefore radiator with no side tanks (as a manual car and no trans cooler?). Question is given parts availability/cost/performance would you try to put everything back as stock or would you recommend a rad with the built in cooler tank, or rad with no tanks and aftermarket oil cooler?
D
#3
Burning Brakes
Thread Starter
Hi Cheburator
Haha so my "handle" is a numberplate of the 944 I had when I joined Rennlist - no imagination. I have a couple of S2s so familiar with their layout but this is definitely a GT, an 89 model. Probably going to be ordering rad from Radtec as they can configure and can build quickly. I do like the idea of separating the oil cooler so avoiding the end tank seal issue completely. Just interested in others experience if they have been through the same loop
Regards
D
89GT - the one that was meant to be working whilst the others are in bits...
85S2 x 2 in surgery
81S - sold and missed
Haha so my "handle" is a numberplate of the 944 I had when I joined Rennlist - no imagination. I have a couple of S2s so familiar with their layout but this is definitely a GT, an 89 model. Probably going to be ordering rad from Radtec as they can configure and can build quickly. I do like the idea of separating the oil cooler so avoiding the end tank seal issue completely. Just interested in others experience if they have been through the same loop
Regards
D
89GT - the one that was meant to be working whilst the others are in bits...
85S2 x 2 in surgery
81S - sold and missed
#4
Rennlist Member
First of all your model year should have an oil cooler fitted. Not sure when the separate oil cooler was introduced - I know for a fact it was std on the 90 S4 and I seem to remember it was std kit for the 89GT's and S4's.
Why someone eliminated it is the more worrisome part - they are a bit exposed [mine has a dink in it]. As for doing what they did that beggars belief. The stock coolers are now quite pricey. Given the radiator system is not likely to be challenged in the UK I dare say you may be able to get away with a radiator with a cooling coil in the end tank [not that I recommend such]. Then you would need the early type hoses to connect it.
You might do well to give Paul a call and see what he can help you with.
Why someone eliminated it is the more worrisome part - they are a bit exposed [mine has a dink in it]. As for doing what they did that beggars belief. The stock coolers are now quite pricey. Given the radiator system is not likely to be challenged in the UK I dare say you may be able to get away with a radiator with a cooling coil in the end tank [not that I recommend such]. Then you would need the early type hoses to connect it.
You might do well to give Paul a call and see what he can help you with.
#5
Burning Brakes
Thread Starter
Hi Fred
Never ceases to amaze me what POs do to these cars. Just as well they are coming into safe(?) hands. I am inclined towards separate rad and aftermarket oil cooler - can't see any point spending £300+ on original parts. Thankfully oil pressure seems fine. Paul is waiting on rad supplier hence thinking of Radtec, esp with build with no tank option.
D
Never ceases to amaze me what POs do to these cars. Just as well they are coming into safe(?) hands. I am inclined towards separate rad and aftermarket oil cooler - can't see any point spending £300+ on original parts. Thankfully oil pressure seems fine. Paul is waiting on rad supplier hence thinking of Radtec, esp with build with no tank option.
D
#7
Rennlist Member
Hi Fred
Never ceases to amaze me what POs do to these cars. Just as well they are coming into safe(?) hands. I am inclined towards separate rad and aftermarket oil cooler - can't see any point spending £300+ on original parts. Thankfully oil pressure seems fine. Paul is waiting on rad supplier hence thinking of Radtec, esp with build with no tank option.
D
Never ceases to amaze me what POs do to these cars. Just as well they are coming into safe(?) hands. I am inclined towards separate rad and aftermarket oil cooler - can't see any point spending £300+ on original parts. Thankfully oil pressure seems fine. Paul is waiting on rad supplier hence thinking of Radtec, esp with build with no tank option.
D
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#8
Rennlist Member
There is an new old stock oil cooler on eBay for £350, which I actually think is not bad value.
https://www.ebay.co.uk/itm/Porsche-928-Engine-Oil-Cooler-92810721201/291892416102?epid=25006171237&hash=item43f624ce66:g:lmcAAOSw8gVX7Olc
They last extremely well - the one in my race car had 345,000km on it, and it still going strong. We replaced it with a bigger Setrab unit, as we felt it was not large enough for an engine producing 50% more power than the standard one. I am keeping it as a spare though for my GTS or may retrofit it to the 89 S4 5spd that I am restoring.
By going with an OEM part, you will save yourself trouble with regards to fitting the aftermarket cooler. Trust me - there is not much space in front of the radiator, especially with cooling flaps etc. Routing the hoses will be a pain too. As for hoses - Pirtek will be happy to supply new ones with swivel fittings, which would be better quality than the OEM stuff.
As a side note - the 1989 S4 most definitely did not have a separate oil cooler - the 5-spd I am restoring has always been serviced by Porsche from day one until it was parked in a barn in 2006 and the oil cooler is in the radiator side tank. The 1989 GT - not sure - my 1990 GT as I said had a separate oil cooler.
https://www.ebay.co.uk/itm/Porsche-928-Engine-Oil-Cooler-92810721201/291892416102?epid=25006171237&hash=item43f624ce66:g:lmcAAOSw8gVX7Olc
They last extremely well - the one in my race car had 345,000km on it, and it still going strong. We replaced it with a bigger Setrab unit, as we felt it was not large enough for an engine producing 50% more power than the standard one. I am keeping it as a spare though for my GTS or may retrofit it to the 89 S4 5spd that I am restoring.
By going with an OEM part, you will save yourself trouble with regards to fitting the aftermarket cooler. Trust me - there is not much space in front of the radiator, especially with cooling flaps etc. Routing the hoses will be a pain too. As for hoses - Pirtek will be happy to supply new ones with swivel fittings, which would be better quality than the OEM stuff.
As a side note - the 1989 S4 most definitely did not have a separate oil cooler - the 5-spd I am restoring has always been serviced by Porsche from day one until it was parked in a barn in 2006 and the oil cooler is in the radiator side tank. The 1989 GT - not sure - my 1990 GT as I said had a separate oil cooler.
#9
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Know? No. But, I happen to have one out on a bench right now:
Units are inches.
length: 26 1/8
height: 2 1/2
width: 3 1/4
The last is not critical as long as the end cap has the correct holes at the correct locations. And, to properly fasten the undertray, it needs three speed nut mounts attached on the underside. In the last picture: the protruding tab with the hole is unused, the two threaded holes on the right are for the mount, the other holes are for the hoses and the single bolt that retains them.
Units are inches.
length: 26 1/8
height: 2 1/2
width: 3 1/4
The last is not critical as long as the end cap has the correct holes at the correct locations. And, to properly fasten the undertray, it needs three speed nut mounts attached on the underside. In the last picture: the protruding tab with the hole is unused, the two threaded holes on the right are for the mount, the other holes are for the hoses and the single bolt that retains them.
#10
Rennlist Member
There is an new old stock oil cooler on eBay for £350, which I actually think is not bad value.
https://www.ebay.co.uk/itm/Porsche-9...cAAOSw8gVX7Olc
They last extremely well - the one in my race car had 345,000km on it, and it still going strong. We replaced it with a bigger Setrab unit, as we felt it was not large enough for an engine producing 50% more power than the standard one. I am keeping it as a spare though for my GTS or may retrofit it to the 89 S4 5spd that I am restoring.
By going with an OEM part, you will save yourself trouble with regards to fitting the aftermarket cooler. Trust me - there is not much space in front of the radiator, especially with cooling flaps etc. Routing the hoses will be a pain too. As for hoses - Pirtek will be happy to supply new ones with swivel fittings, which would be better quality than the OEM stuff.
As a side note - the 1989 S4 most definitely did not have a separate oil cooler - the 5-spd I am restoring has always been serviced by Porsche from day one until it was parked in a barn in 2006 and the oil cooler is in the radiator side tank. The 1989 GT - not sure - my 1990 GT as I said had a separate oil cooler.
https://www.ebay.co.uk/itm/Porsche-9...cAAOSw8gVX7Olc
They last extremely well - the one in my race car had 345,000km on it, and it still going strong. We replaced it with a bigger Setrab unit, as we felt it was not large enough for an engine producing 50% more power than the standard one. I am keeping it as a spare though for my GTS or may retrofit it to the 89 S4 5spd that I am restoring.
By going with an OEM part, you will save yourself trouble with regards to fitting the aftermarket cooler. Trust me - there is not much space in front of the radiator, especially with cooling flaps etc. Routing the hoses will be a pain too. As for hoses - Pirtek will be happy to supply new ones with swivel fittings, which would be better quality than the OEM stuff.
As a side note - the 1989 S4 most definitely did not have a separate oil cooler - the 5-spd I am restoring has always been serviced by Porsche from day one until it was parked in a barn in 2006 and the oil cooler is in the radiator side tank. The 1989 GT - not sure - my 1990 GT as I said had a separate oil cooler.
That's a good price. I believe Roger sent me a new one for my '90 GT and it was $565 U.S. He does not carry the rebuilt ones because his rebuilt ones were failing after 6 months. I had a local radiator shop repair mine and it did not work. They leak at the tank on the oil line side.
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That's a good price. I believe Roger sent me a new one for my '90 GT and it was $565 U.S. He does not carry the rebuilt ones because his rebuilt ones were failing after 6 months. I had a local radiator shop repair mine and it did not work. They leak at the tank on the oil line side.
The ‘trick’ set-up is using both the side-tank cooler and the under-cooler unit. Greg Brown sells a set of hoses for this conversion.
#12
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1989 models had cooler in radiator. The oil "added" heat load to the coolant, which although Porsche apparently thought was an issue, does not seem to be.
1990 models had cooler under radiator. Cooler in radiator was eliminated. Good idea in the very mild climate of Germany, where traffic "jams" were rare in 1990. Bad idea almost everyhere else. The oil doesn't get cooled in slow or stop and go traffic. 270 degree oil temps are common in US cities, or almost anywhere with traffic
Camshaft wear is greatly accelerated, because of this.
1990 models had cooler under radiator. Cooler in radiator was eliminated. Good idea in the very mild climate of Germany, where traffic "jams" were rare in 1990. Bad idea almost everyhere else. The oil doesn't get cooled in slow or stop and go traffic. 270 degree oil temps are common in US cities, or almost anywhere with traffic
Camshaft wear is greatly accelerated, because of this.
#13
Bad idea almost everyhere else. The oil doesn't get cooled in slow or stop and go traffic. 270 degree oil temps are common in US cities, or almost anywhere with traffic
Camshaft wear is greatly accelerated, because of this.
Camshaft wear is greatly accelerated, because of this.
what is this:
The ‘trick’ set-up is using both the side-tank cooler and the under-cooler unit. Greg Brown sells a set of hoses for this conversion.
#14
Rennlist Member
Greg sells a set of custom hoses that go from the engine to the rad cooler to the oil cooler then back to the engine (may have mixed up the order).
It essentially adds a 3rd hose to the mix and adds thermal capacity to the system utilizing OEM components. It's pretty clever.
It essentially adds a 3rd hose to the mix and adds thermal capacity to the system utilizing OEM components. It's pretty clever.
#15
Drifting
I retro fitted a GT oil cooler to my 87 S4
Second best mod I ever did, however like you the original oil cooler had effectively been bypassed by the PO, so this was a massive improvement
Oil pressure was restored on track, and to a lesser extent with road use
Greg's concerns about airflow in traffic jams are interesting, never considered that before, but I can't see how a car can be under any serious load when stationary in traffic, so maybe I've missed something
As Alex said, that used price isn't too bad I think I paid nearly £300 ten years ago (new), but the OEM hoses work fine in my experience, many thanks to Roger for supplying used hoses at a price I could afford
I hadn't quite sorted out the rubber bushes when this pic was taken
Second best mod I ever did, however like you the original oil cooler had effectively been bypassed by the PO, so this was a massive improvement
Oil pressure was restored on track, and to a lesser extent with road use
Greg's concerns about airflow in traffic jams are interesting, never considered that before, but I can't see how a car can be under any serious load when stationary in traffic, so maybe I've missed something
As Alex said, that used price isn't too bad I think I paid nearly £300 ten years ago (new), but the OEM hoses work fine in my experience, many thanks to Roger for supplying used hoses at a price I could afford
I hadn't quite sorted out the rubber bushes when this pic was taken