I'm about to stick an oil cooler and power steering cooler in my project car, I wanted to know if those items are street legal (Especially in California).

 

dunno, but how can a cooling unit be illegal?

 

All Z's come with an oil cooler already, and some are sold with a power steering cooler. Can't see why it would be illegal?

 

As long as they allow the vehicle's emissions systems to operate normally then they are legal. If the oil cooler prevents the car from reaching operating temperature (a very unlikely scenario) then it can be considered illegal. Power steering is not part of the emissions package so you can do whatever you want to it.

You might want to paint the coolers a semi-gloss black so they look factory and an ignorant cop doesn't confuse them with an intercooler. Stealth is important on a modified street car in California.

 

I didn't know Z's had an oil cooler. I can see a small P/S cooler in front of my Z .

My project car is a non-turbo Supra, I know it doesn't have an oil cooler and has a thin tube for a p/s cooler.

 

I shouldn't have too much problem finding a black P/S cooler & oil cooler. However, the oil cooler lines will be stainless steel (which would be a dead give away to cops). Is there other durable lines I can use that are black??

 

XRP makes a nice black CPE textile braded push on hose that's good for 250 psi at 300 degrees F. I've used it for fuel and oil on customer's cars that don't want to spend the extra money for the braided stainless CPE hose.

Call George at TMR 714-771-1348.

 

its a crappy oil cooler - the heat exchanger is at the oil filter mount, and it dumps heat to the coolant. ie, its an oil<->water(coolant) exchanger vs an oil<->air unit. so... point being, is that it doesn't (IMO) work very well.

after putting gauges in my car (and, ahem, an APS ST), temps are a *BIG* issue. oil quickly runs up to the 240 degree range and clearly would continue to go up. coolant temps also start to climb way beyond safe levels. i didn't have gauges before the turbo, so can't give you hard numbers, but a moderately hot day running mobil1 15w50 still had oil pressure WAY low coming in off the track. IMO, tracking the car requires an auxilliary oil cooler.

if you decide to add an aux oil cooler, make sure you get a sandwich plate that has a thermostat, or else daily driving will have a hard time getting it up to temp.

ahm

 

Oil to water heat exchanges (fluid to fluid) are much more efficient then oil to air heat exchangers. They don't need to be large to work well. 240F oil temps are a concern if you're running regular oil but nothing to worry about if you're running synthetic. I ran a Niagra oil to water heat exchanger on my racing 240Z and never had an oil or water temp problem caused by the cooler.

 

i should have been more clear... the problem is not specifically that the exchanger is oil<->water. the problem is capacity of the system as fitted stock to the car. plenty for street use and novice track days. once you start putting sticky tires on and know your way around a track, again IMO, the stock systems are not up to the task.

for longevity, knowing what i know now, if you are doing regular track days, an additional oil cooler and larger capacity (and at least as efficient as stock) radiator should be in the budget IMO. i have no data to indicate whether the larger koyos (et al) are actually better radiators than oem, but i have a feeling i'm going to have to try one and see. making a duct from the bumper inlet all the way through the intercooler/radiator sandwich should help some, but other than that, i'm not sure what else to try...

ahm

 

You can run both power steering and oil cooler units in California.

As was noted above, the stock cooliing systems are not up to the task of keeping the car cool if you run hard on a track. A three core aluminum radiator is a big plus in my experience with the G. I would also recommend you consider running some water wetter (Redline has a pretty good product) in the water mixture to help with the thermal exchange. A bigger oil cooler is a very good idea, as is an oil pan spacer, to run a bit more oil capacity and thus a larger volume of oil to absorb and distribute the heat. For most folks that ought to take very good care of your needs.

You can go a couple of steps farther if you want, such as a thermal dispersant coating on the lower oil pan, and if you really want to go all out, something like an amsoil bmk-13 dual bypass filter system. That unit will take out all particulates in suspension which are greater than one micron in size (standard filters only remove particulates above 30 microns....and scoring probably begins at about 10 microns). This is important because, especially with turbo, you are going to get particulate and that traps heat and spreads it to the surrounding oil. So you get dual benefit by reducing friction and wear on the motor, as well as reduction in thermal heat attraction and retention. All those goodies will put your oil capacity up to about 12 quarts (use syn). For street use, all that is not necessary. But if you have an expensive built motor and FI, and if you track the car, it will run very happy under highly demanding conditions.

I have run in hot temps with this set up, very hard, and water temps on track stayed between 95 and 100 C through the run, from the warm up lap to the end of the 25-30 minute session, climbed to 105 C for a few moments after returning to paddock (no more fast air flow across the radiator and cooler), and then quickly settled back to around..........95 C. On the street the car runs between 95 and 100 C depending on traffic conditions, etc. There are also thermal barrier coatings on the turbos and certain of the intake pipes, the upper plenum etc., but those are more directed to keeping the intake as cold as possible for power production. A vented hood will also help to express ambient radiated heat from the block more effectively, and this is good not only for the intake, but reduces heat fatigue on surrounding components. If you can, get a hood unit with a scoop for intake at the front high pressure zone, so that it sets up a good "draw" out of the top vents to suck more air through the compartment and express more heat. Finally, an iso-thermal upper plenum is worth looking into as well, such as the one Motordyne offers, again that is more for keeping the intake air charge cool.

As for the steering, as soon as you put larger and stickier tires on the car, you are taking it to demand levels beyond those spec'd and you can overheat it quickly, especially on a twisty circuit like Buttonwillow, Spring Mountain Pahrump, Fernley, the infield at Cal Speedway, etc.