My dirty daily mk2 gets the odd trackday hooning. Fully rebuilt 8v, fast Road cam, ported head , compression hike , the usual. I did fit a new oil pump , water pump/stat/senders and oil cooler matrix on the oil filter. According to the mfa, I'm getting 125 or so degrees oil temp on the last outing, after a few laps .I'm no driving God, but I'd be pushing pretty darn hard. Coolant stays slightly left of centre , no smoking etc. Oil temps on the road rarely get to 100 degrees. I'm running 10w40 semi synthetic , not supermarket rubbish. And it gets changed every few thousand miles . Opinions ? I'm considering making it a bit more track focused , stickier tyres, more aggressive suspension etc, so I'll be working the engine harder. .. But I still want to be able to drive it to the Ring for example .
Those readings are very high. I'd be tempted to change the sender! The best course of action if the readings are true would be to install a Mocal oil cooler. Mine is maybe 120mm ish x 360mm ish and fitted vertically behind the right hand inner spot light grille hole. You have to remove the water cooled unit below the oil filter housing, blank off the water pipes and replace it with the Mocal oil sandwich plate, At some point I remember using liquid gasket on the sandwich plate to oil cooler housing. Even on the 'ring or during races the temp never exceeded 104. could do some pics to help if this is the route you are going to take. Do you think the stat is opening as those temps are high!
My thermostat ? Yes, if anything my coolant stays marginally low, and I verified the gauge reading with an IR thermometer . Oil Temps checked and I'm happy with the sender.
The book says something like 130 degrees is ok but seems a little on the high side to me. As above if you are doing track work a Mocal would be good a shout. Also get the added bonus of a slightly higher oil capacity. Running a thermostatic plate alongside the OE cooler on mine. Mocal is hidden nicely down behind one of the bumper vents. Used to see 115 degrees regularly. Now its around 90 on a road run, 106 odd after a circuit session.
The Mocal sandwich plate just mounts on the base of it using a longer oil filter shaft through the middle of both. Then the filter screws onto the end of that. Terrible pic but imagine this threaded onto where the filter normally goes:
Ah, so you did keep the water to oil one . Sorry , I wanted to confirm . Where did you get the longer threaded shaft?
Yeah kept the OE water one too. You may need to use a shorter oil filter (Polo GTI one fits) to avoid the crossmember fowling the filter but I managed to squeeze a normal Mk2 GTI one in without issue. The threaded shaft came in the Mocal kit but I'm sure you can buy them separately. This kind of thing: https://www.ebay.co.uk/p/Mocal-MS20/667092483?iid=352182140025&chn=ps
I did the same as JM on my mk2 16v with an ABF block, a standard filter fits on fine its just a little tighter on clearance when you change the filter but its still possible.
This makes for an interesting read as experienced the same issue. Having done Curborough with no overheating issues I thought I would dip my toe in the water and do one of the 20 min sessions at Rockingham during Inters in 2017. After 4 laps the oil temp hit 128 and coupled with a couple of other issues that I won't bore you with here it's put me off having another go. I've been invited to join a friend at a track day in April and this issue is putting me off committing which is a shame as the car is fine on spirited road use. How much did the mocal parts come to Jim and how difficult was the fitting? (My car is a 5 door Mk2 16v with ABF/KR)
It makes me wonder why vw moved from the air to oil cooler in the mk1 Gti to the water to oil item in the mk2 . I had no issues on the Ring last Easter , but normal circuits really work the oil . Opie recommended changing to 5w40 , from the 10w40 I currently use . But said it sounds like a better cooler is required.
Similar oils to what I run return to tank at a scavenge temp of 170 in a work application What I'm quoting is not an automotive application, there must be 'rules' available for car lubes on the web somewhere Jon
The oil might be able to take 150 degrees if it's a fully synthetic but at that temperature it will be like water and the pump won't be able to make any pressure. I ran my TT at inters last year as well in the afternoon sessions it was very hot. After 20 minutes the oil temps were only around 115 degrees. I run a Mocal oil cooler with an 80 degree stat. You can get a full kit from Matt lewis racing. http://www.mattlewisracing.co.uk/product.php/1132/889/engine_oil_cooler_kit___matt_lewis_racing The thermostat is available in 80 degree or 92 degree . If it's a road car don't run it without a thermostat. The thermostat adds £20 to the price. you just then need to select a suitable cooler. Dependent on the engine power output and area you have available to fit it something like a 13 row will ususlly do. http://www.mattlewisracing.co.uk/product.php/356/0/mocal_oil_cooler___matt_lewis_racing
I really need to do a tidy up more often .... I actually found a new Mocal thermostatic plate and fittings I'd forgotten I'd bought , when tidying around my mk2 earlier ... I'm tempted to try a cheap cooler and plumb some pipes .
It gets better ... I was chatting to my future brother in law last night and he offered me a new 10 row cooler , free! Says he'll never use it . Happy days . And my best mate can make the oil lines for me , proper swaged ones . Now , what's that short oil filter? I use Mahle OC47 usually .