the amazing oil cooler delete kits
Mar 10, 2015, 08:01 PM
#1
the amazing oil cooler delete kits
https://secure.buschurracing.com/cat...aa532cd74b74a7
http://www.streettunedmotorsports.co...ler_delete.htm
whats amazing is they and others are selling these kits with no explanation of what else would need to be done to be able to plug those ports.
so here is how the OFH (oil filter housing) works. the oil pump pumps pressure to the housing. when the oil is cold oil can go to the cooler and to the engine. in this case the easiest path of resistance is to the engine. so the cooler gets oil and oil pressure but no flow. when the oil gets to operating temperature the thermostat closes off the direct path to the engine. at this point all oil must go through oil cooler first and then to the engine. there is no bypass path.
so what would happen if you used these plugs to eliminate your oil cooler? well you would be fine if your oil never reached operating temps as with a drag car. but at operating temps with a driven car the thermostat would open and send all oil to a blocked off oil cooler pathway. THIS IS BAD. VERY BAD. your engine will have very high oil pressure at the housing and very nill at the engine.
to eliminate this problem the thermostat would need to be removed as well. so why are venders selling these things without mention of this?
http://www.streettunedmotorsports.co...ler_delete.htm
whats amazing is they and others are selling these kits with no explanation of what else would need to be done to be able to plug those ports.
so here is how the OFH (oil filter housing) works. the oil pump pumps pressure to the housing. when the oil is cold oil can go to the cooler and to the engine. in this case the easiest path of resistance is to the engine. so the cooler gets oil and oil pressure but no flow. when the oil gets to operating temperature the thermostat closes off the direct path to the engine. at this point all oil must go through oil cooler first and then to the engine. there is no bypass path.
so what would happen if you used these plugs to eliminate your oil cooler? well you would be fine if your oil never reached operating temps as with a drag car. but at operating temps with a driven car the thermostat would open and send all oil to a blocked off oil cooler pathway. THIS IS BAD. VERY BAD. your engine will have very high oil pressure at the housing and very nill at the engine.
to eliminate this problem the thermostat would need to be removed as well. so why are venders selling these things without mention of this?
Mar 10, 2015, 09:38 PM
#3
I just picked up the hardware to do the oil cooler delete from the local hydraulic hose supply place (about $6 for two 18x1.5 plugs and crush washers) and started thinking about this very issue.
I THINK you are wrong in your understanding though as I believe the thermostat will allow oil to make it to the engine as a failsafe should the oil cooler route be blocked. I can't say for certain though without thoroughly looking over the housing passages and messing with the thermostat some more. I might have to order up an oil filter housing gasket and take a closer look though. The pressure by-pass will prevent any crazy high oil pressure but obviously that's the least of your concerns at that point.
I measured the HKS thermostat I have here. It's 24mmx1.5mm pitch. I'm thinking a simple plug and crush washer would create the needed bypass route if you are right.
FWIW, a local buddy did the delete on his car and many others have done it on street cars. I believe he put a decent amount of street miles on it without issue. It completely hammered the rod bearings though the first time he took it down the track. It looked like either the machine shop screwed up on tolerances and the stress of a drag pass finally killed it, or he lost oil pressure all together because every rod bearing was equally damaged. I'm betting he starved the pump though as is common, but if you are right, we might have a better explanation.
I THINK you are wrong in your understanding though as I believe the thermostat will allow oil to make it to the engine as a failsafe should the oil cooler route be blocked. I can't say for certain though without thoroughly looking over the housing passages and messing with the thermostat some more. I might have to order up an oil filter housing gasket and take a closer look though. The pressure by-pass will prevent any crazy high oil pressure but obviously that's the least of your concerns at that point.
I measured the HKS thermostat I have here. It's 24mmx1.5mm pitch. I'm thinking a simple plug and crush washer would create the needed bypass route if you are right.
FWIW, a local buddy did the delete on his car and many others have done it on street cars. I believe he put a decent amount of street miles on it without issue. It completely hammered the rod bearings though the first time he took it down the track. It looked like either the machine shop screwed up on tolerances and the stress of a drag pass finally killed it, or he lost oil pressure all together because every rod bearing was equally damaged. I'm betting he starved the pump though as is common, but if you are right, we might have a better explanation.
Mar 10, 2015, 10:27 PM
#4
So I couldn't help myself to know for sure. 94AWDcoupe is potentially right.
Here is the thermostat and it measures in at 50mm depth to the seat.
Here is the thermostat housing with a depth of 53.55mm.
At room temperature, the plate that would seal off the passage from oil filter to engine is ~3.5mm away from the valve seat. Thus, the oil cooler route is open and oil could travel that path but the pressure drop across the cooler would have to be lower than the pressure associated with going through that 3.55mm gap.
The thermostat gets longer with heat. Fully extended it reaches a length of 64mm. Sorry, I couldn't hold it, measure it and snap a picture at the same time so you'll just have to trust me. Here it is fully extended.
Clearly...if it has the ability to extend to 64mm, it can easily close up that 3.55mm gap. However, the plate is spring loaded and has 10mm of available travel. Again, couldn't do three things at once, but here is the plate in the fully compressed position.
So...thermostat fully extended (64mm) minus the plate travel (10mm) leaves us with 54mm total length...Technically...it could definitely close off the passage completely. Now, add in the pressure of the oil and I bet this would NEVER happen. However, it seems like it will clearly increase the oil pressure in the filter housing before the block and will impede flow, how much so is the real question. I'll be chopping up the OEM thermostat or getting a plug to replace it just for piece of mind, but I don't think it will make a huge difference.
Glad you brought this up 94AWDcoupe, I was on the fence about looking at it more or just trusting the common thought that it was fine.
Here is the thermostat and it measures in at 50mm depth to the seat.
Here is the thermostat housing with a depth of 53.55mm.
At room temperature, the plate that would seal off the passage from oil filter to engine is ~3.5mm away from the valve seat. Thus, the oil cooler route is open and oil could travel that path but the pressure drop across the cooler would have to be lower than the pressure associated with going through that 3.55mm gap.
The thermostat gets longer with heat. Fully extended it reaches a length of 64mm. Sorry, I couldn't hold it, measure it and snap a picture at the same time so you'll just have to trust me. Here it is fully extended.
Clearly...if it has the ability to extend to 64mm, it can easily close up that 3.55mm gap. However, the plate is spring loaded and has 10mm of available travel. Again, couldn't do three things at once, but here is the plate in the fully compressed position.
So...thermostat fully extended (64mm) minus the plate travel (10mm) leaves us with 54mm total length...Technically...it could definitely close off the passage completely. Now, add in the pressure of the oil and I bet this would NEVER happen. However, it seems like it will clearly increase the oil pressure in the filter housing before the block and will impede flow, how much so is the real question. I'll be chopping up the OEM thermostat or getting a plug to replace it just for piece of mind, but I don't think it will make a huge difference.
Glad you brought this up 94AWDcoupe, I was on the fence about looking at it more or just trusting the common thought that it was fine.
Last edited by 03whitegsr; Mar 10, 2015 at 11:05 PM.
Mar 11, 2015, 01:49 AM
#5
I always thought the common practice was to loop a line when removing cooler. it certainly is on DSM tuners. somehow that knowledge is absent on evo forums. local here just built his evo engine and had phoned me about low oil pressure at the head. like 5psi. and at the OFH there was 125psi. I advised him to pull the head. seeing nothing blocked he spun the pump with drill. still 125 at OFH and 25psi at oil sender on block. baffled and about to pull pan and pump he then mentioned he wasnt using a cooler and just plugged the outlets. I was certain you cant do that. he was using an Tomei Oil Thermostat Killer. which I havent seen but assume sends oil to cooler both hot and cold. and his low oil pressure was present hot and cold.
most who have an oil pressure gauge would be plumbing it at the OFH. so they would never even know they had a problem. this consumer was concerned from the head being noisy so he started measuring pressures at different locations. I am certain that many have ruined their engine builds from this absurd mistake. its just uncanny how many never report engine losses. most go away broke and unhappy without adding the pain of having to report it on forums.
most who have an oil pressure gauge would be plumbing it at the OFH. so they would never even know they had a problem. this consumer was concerned from the head being noisy so he started measuring pressures at different locations. I am certain that many have ruined their engine builds from this absurd mistake. its just uncanny how many never report engine losses. most go away broke and unhappy without adding the pain of having to report it on forums.
Last edited by 94AWDcoupe; Mar 11, 2015 at 08:14 PM.
Mar 11, 2015, 11:04 AM
#7
I've put about 20k on with no oil cooler. I'll build a kit eventually.
Needed a quick fix after something pierced the OEM unit. All is still fine with the engine at nearly 170k now. It is only driven on the street however.
Last UOA 5k ago was normal as it gets and how they have always been
Needed a quick fix after something pierced the OEM unit. All is still fine with the engine at nearly 170k now. It is only driven on the street however.
Last UOA 5k ago was normal as it gets and how they have always been
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Mar 11, 2015, 01:10 PM
#8
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many many people run these delete kits. I think that we would have heard horrer stories by now if in fact they did cause failures. I have mine deleted. Just spent a full day on the dyno making multiple pulls and butt loads of power with no issues.
Mar 11, 2015, 02:03 PM
#9
Sure...
You could also toss a $5 plug in the hole after removing the thermostat and rest easy knowing you don't have anything trying to block the oil path...
But sure, I get how pride over not admitting a simple mistake might force you to make that kind of choice.
Kind of makes me wonder how many turbos that died from oil starvation might have been related too... The lines from the filter housing after all would pull pressure for the turbo before the thermostat.
You could also toss a $5 plug in the hole after removing the thermostat and rest easy knowing you don't have anything trying to block the oil path...
But sure, I get how pride over not admitting a simple mistake might force you to make that kind of choice.
Kind of makes me wonder how many turbos that died from oil starvation might have been related too... The lines from the filter housing after all would pull pressure for the turbo before the thermostat.
Last edited by 03whitegsr; Mar 11, 2015 at 02:38 PM.
Mar 11, 2015, 02:08 PM
#10
Just a visual aid to help out. This is drawn to the OEM thermostat and housing dimensions.
Here is how it works at low temps.
Here it is at high temps.
As you can see, the valve (purplish plate) fully compresses the spring when the thermostat element (orangish cylinder) is fully extended. The only way oil can get around that plate is if the oil pressure forces the thermostat element back. How much force this would take and at what temperature it would try to fully close, I have no idea. Clearly though, it is trying and has the travel needed to completely block the port and fully bind the spring behind the valve plate.
Here is how it works at low temps.
Here it is at high temps.
As you can see, the valve (purplish plate) fully compresses the spring when the thermostat element (orangish cylinder) is fully extended. The only way oil can get around that plate is if the oil pressure forces the thermostat element back. How much force this would take and at what temperature it would try to fully close, I have no idea. Clearly though, it is trying and has the travel needed to completely block the port and fully bind the spring behind the valve plate.
Last edited by 03whitegsr; Mar 11, 2015 at 03:31 PM.
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Mar 11, 2015, 02:48 PM
#11
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I'm confused...are you calling me out about this pride thing? lol....i will admit a mistake, but I am just following buschur/stm. Maybe they did leave some instruction out or maybe you guys are wrong...idk...i am just looking for the right answer considering I just finished my build and I want it to last. Waiting for buschur or stm to chime in
Mar 11, 2015, 03:44 PM
#12
there are lots of factors here. the thermostat has to be working correctly for one. and second it would take a long time even in florida for the thermo to be fully extended. like 45 minutes. lots of high performance builds dont drive nearly that long to even see this problem. ten pulls on the dyno aint gonna do squat to get the oil hot enough. rest assured this problem is for real and the thread is titled correctly. thermo guts need to be removed to use plugs instead of a cooler. this thread is young. people will be getting pissed when they find out they lost their engine do to this simple but massive error..
Mar 11, 2015, 05:27 PM
#13
subscribed... Regarding loop the oil hose. isn't going to impact oil pressure? I have a friend using a looped oil cooler line. The tuner mentioned issues with oil pressure during the pulls. Any thoughts? What about HKS low thermostat? according to the post, not a good idea with oil cooler delete kit.
Mar 11, 2015, 05:48 PM
#15
Jerry thank you for making the thread this was something I was completely ignorant to as well. Never had a OFH apart so thanks you 03white for the visual and diagrams. Now to find a plug for the thermostat until I get a chance to put a nice kit together (Setrab Cooler and AN Fittings)
DBB PT, I pull oil from head. Turbo has the same minimal shaft play its always had after almost 70k.
DBB PT, I pull oil from head. Turbo has the same minimal shaft play its always had after almost 70k.