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Discussion Starter #1
for various reasons, i want to change the fittings on the 2ZZ Lotus (only) oil cooler take off plate to male AN10 . Does anyone know of such a fitting??.

The factory male fitting partially unscrewed in my pic, measures 0.885" x 14 tpi where it threads into the housing, and its fairly loose in the housing, but the alloy washer stops it leaking (sort of). I thought this might be some obscure SAE thread size, but pirtek says no, probably just sh!t machining of both parts.

The male is about 10 to 12 thou over-diameter what a notional 7/8 SAE fitting should be and the female is about 20 thou over what you would expect.

The common AN10 fittings are supposed to be 7/8 x 14, but then measured various brands they are in the .860-865" range, so looser yet again

if i cant find something, i'll weld on 2 stubs with AN10 male

thanks and merry xmas to all
 

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Might ping BOE, I believe their fitting that comes with the rear oil cooler fits well. They might sell just the fittings.
 

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Discussion Starter #8
thanks again, just to close this out, i have confirmed that 5/8 BSPP should have 0.890" as the major diameter of the male thread and this matches the fittings I have. the female thread in the Lotus adaptor block however is far to big, so i can only assume very poor quality control. I have looked at several makers of fittings, and none i have found so far, can confirm their male thread is actually this diameter (0.890" major diam) .I checked one at a local vendor and it was 0.870", so 20 thou too small. The Pegasus site referenced above is for a 1/2" BSPP fitting and if their measurement of 0.81" is correct, its also 0.010" undersized. Again, thanks guys. i'll be able to sort this out now
 

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I don't have the stuff in front of me but you might tell us what you are doing. If you are changing some things, changing the thermostat is a useful addition,and may lead to easier to find fittings

 

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thanks again, just to close this out, i have confirmed that 5/8 BSPP should have 0.890" as the major diameter of the male thread and this matches the fittings I have. the female thread in the Lotus adaptor block however is far to big, so i can only assume very poor quality control. I have looked at several makers of fittings, and none i have found so far, can confirm their male thread is actually this diameter (0.890" major diam) .I checked one at a local vendor and it was 0.870", so 20 thou too small. The Pegasus site referenced above is for a 1/2" BSPP fitting and if their measurement of 0.81" is correct, its also 0.010" undersized. Again, thanks guys. i'll be able to sort this out now
If you look at the second link I gave, there are 5/8" BSP to AN-10 fittings. With some teflon tape and the O-ring seal, you should not have a problem.

Later,
Eldon
 

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thanks again, just to close this out, i have confirmed that 5/8 BSPP should have 0.890" as the major diameter of the male thread and this matches the fittings I have. the female thread in the Lotus adaptor block however is far to big, so i can only assume very poor quality control. I have looked at several makers of fittings, and none i have found so far, can confirm their male thread is actually this diameter (0.890" major diam) .I checked one at a local vendor and it was 0.870", so 20 thou too small. The Pegasus site referenced above is for a 1/2" BSPP fitting and if their measurement of 0.81" is correct, its also 0.010" undersized. Again, thanks guys. i'll be able to sort this out now
Also, if you look here: https://www.lotustalk.com/threads/oil-cooler-sandwich-plate.465306/#lg=thread-465306&slide=0
you will see what I did.
Later,
Eldon
 

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Discussion Starter #12 (Edited)
thanks Eldon. i see you have ditched the factory plate . I have many years of experience with 2ZZ's, mostly in Toyotas but some Lotus. I recognise the Lotus system can lead to oil being over cooled. For road cars and occasional track day cars, I have have had no problems with the factory Toyota oil heater/heat exchanger that Lotus discarded. On my race car, i have found that system works well for 4-8 lap races, but over that, the oil is getting too hot (ie its in excess of the circa 95 the water system runs at). So, i'm going to experiment by adding the factory lotus take off plate + using the oil heater. Potentially, the oil/water 'heater" will keep the desirable function of fast oil temp rise and the external air to oil cooler, will manage the excess temps . its an experiment!!

Finally, I would be pleased to hear from anyone using a laminova oil to water intercooler and especially if they have data to support how well it works in real track use applications
 

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thanks Eldon. i see you have ditched the factory plate . I have many years of experience with 2ZZ's, mostly in Toyotas but some Lotus. I recognise the Lotus system can lead to oil being over cooled. For road cars and occasional track day cars, I have have had no problems with the factory Toyota oil heater/heat exchanger that Lotus discarded. On my race car, i have found that system works well for 4-8 lap races, but over that, the oil is getting too hot (ie its in excess of the circa 95 the water system runs at). So, i'm going to experiment by adding the factory lotus take off plate + using the oil heater. Potentially, the oil/water 'heater" will keep the desirable function of fast oil temp rise and the external air to oil cooler, will manage the excess temps . its an experiment!!

Finally, I would be pleased to hear from anyone using a laminova oil to water intercooler and especially if they have data to support how well it works in real track use applications
I only switched because everybody on here complained about the OEM bypassed too much oil when it still was not at temp. I did not watch the oil temp before switching but I do now. I still have both coolers installed and I only see the oil temp go a little higher, 10 - 20 degrees, than the water temp after a 20-30 minute track session. Your oil temp should be higher than your water temp since most of the cooling in the motor is done via the oil not the water. As a rule of thumb, your oil should be 20-40 degrees hotter than the water. @Jack has the Lavinovai oil/water heat exchanger and he is a pretty strong proponent of it. When we ran it on the circle track car, we had problems of overheating the water so just went back to a separate oil cooler. Thus, make sure your radiator can handle the increase capacity that you are asking of it. My engine builder would not let me install a oil temp gauge on one of the race cars because he said I did not want to see the value. I was told that the oil temp was north of 300 degrees. We just changed oil frequently. Never had a problem with the motor related to oil failure. In fact, since the motor was always primed with an accusump before starting, there was one rebuild where the bearings were not replaced because they looked like new.

Later,
Eldon
 

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I have a laminova on my 07 Exige S (BOE TQ300). What would you like to know @terryob?

At Sonoma (Sears Point) in August 2019, I logged oil temps at 94-99°C on the 3rd lap, oil temps levelled out at 101-103°C by the 7th lap. The corresponding water temps level out at 87-89°C.

I have no AC or heater core and a Proalloy twin-row 45mm radiator.
 

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Discussion Starter #15
many thanks, some real facts. what size/length cooler did you fit?? do you notice the oil heats up fairly quickly, pretty much in line with water temp??
 

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I used the larger C43-330 (330mm) core-based oil-water cooler which I got from these folks: https://www.batinc.net/laminova-cooling.

I understand it is common to use the medium, C43-180 (180mm) core on the Toyota S2 Lotus: elise-spares has a kit. I'd use this size for an NA car.

The oil temp lags the water temp for a short time (one lap from pretty much cold start) but overtakes very quickly.

I do not have data on how this compares to the stock setup in terms of ramp temp. I guess it is a bit slower to 80°C because I have no oil-line thermostat and the radiator water is cold until the water-line thermostat opens (I like to drive the car gently to warm up rather than idle for long periods).

I believe (although no data) that our larger Aluminium baffled oil pans with their higher oil volume are likely providing quite a bit of oil cooling too.
 

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Is your Laminova installed on the hot side, I.E. before the front radiator, or on the cold side after the water has passed through the rad?
 

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It is on the cool-side, just before the coolant thermostat. This was purely for installation convenience.

I cut that convenient straight run of coolant hose on the lower right side of the engine bay. I actually flipped the severed section of hose on the thermostat side to give me a bit more length to the run (I left the lower arm a bit longer so that when it became the upper arm, the lower bend is shifted leftward toward the ECU a few inches).

I have also installed a 180mm in an NA car and there is plenty of space for it without the hose-flip trick.

1256632
 

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It is on the cool-side, just before the coolant thermostat. This was purely for installation convenience.

I cut that convenient straight run of coolant hose on the lower right side of the engine bay. I actually flipped the severed section of hose on the thermostat side to give me a bit more length to the run (I left the lower arm a bit longer so that when it became the upper arm, the lower bend is shifted leftward toward the ECU a few inches).

I have also installed a 180mm in an NA car and there is plenty of space for it without the hose-flip trick.

View attachment 1256632
I had the 180mm Laminova, but found that after I installed a 170 degree thermostat and Pro Alloy 45mm radiator, my water temp dropped and so did the oil temp for normal street use. On track it worked perfectly well.
I since installed a Rev 300 SC, and went with a rear mounted oil cooler.
 
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