Which HPL for an autoX car?

[malibuguy79]

Ive been reading and reading and I just cannot get a grasp on what would work best for me.

The car, is a turbocharged 96 Tercel. As I currently have it set up it produces around 150whp and 170wtq with a rising boost curve. I am using a bottom end from a 93 paseo (1st gen 5efe), a head from a 95-6 (2nd gen). It has about 10.1-10.3 compression ratio, 1st gen valve springs to control valve float (2nd gen floats after 5000rpm with boost).

The car is driven to events but is not a regular driver. It might see roughly 2500miles a season.

I ran the car last season with Redline 5w40 and I felt it may be a little thin to use. I hope to install an oil temperature gauge for next season. No plans to run an oil cooler currently as packaging is quite tight with the a2w charge cooler and its own dedicated radiator. I did make a custom baffled oil pan that also holds about a half quart more capacity. I normally let the car idle between runs with the hood open.

I am not too concerned with winter as I will change the oil to some basic 5w30 synthetic as it will be parked for most cold months.

 

[Jetronic]

Autocross runs are quite short, I doubt you can get the oil hot enough to make redline 5W-40 too thin. But maybe elaborate on why you feel it might be too thin?

Also 5W-30 has the same winter performance as 5W-40.

I don't think that you can do substabtially better with HPL as you do with redline high performance 5w-40

 

[JohnnyJohnson]

My money says QSFS 5W-40 would do just as good and job for less than half price. What do you do change out the oil once a season?

 

[malibuguy79]

My money says QSFS 5W-40 would do just as good and job for less than half price. What do you do change out the oil once a season?

Well...for a while there I was changing motors every season lol

I finally have a combination that should endure all I throw at it. You are likely right just about anything should suffice. I just want to protect what I have.

 

[malibuguy79]

Autocross runs are quite short, I doubt you can get the oil hot enough to make redline 5W-40 too thin. But maybe elaborate on why you feel it might be too thin?

Also 5W-30 has the same winter performance as 5W-40.

I don't think that you can do substabtially better with HPL as you do with redline high performance 5w-40

I am speculating about needing thicker oil. I need to get a temp gauge to know for sure.

I changed the oil for the winter so I can just have fresh stuff in there plus I wanted to inspect the filter. The 5w30 Total thats currently in the car is just what I happened to have. I didnt want to put in top tier stuff only to run it maybe 500miles

 

[addyguy]

If not using it in really cold weather, a full-syn 15W-40 HDEO should cover all bases - Rotella T6 15W-40 or Delvac Extreme 15w-40.

 

[twX]

I ran the car last season with Redline 5w40 and I felt it may be a little thin to use.

That oil is on the thicker side of a 40 grade, and has an HTHS of 4.4 cP. It's probably much thicker than it needs to be for short autocross runs since the oil shouldn't get too hot. You'll get a better sense of how appropriate the grade is once you install an oil temperature sensor.

If we assume that the 5W-40 is sufficiently thick for oil temperatures up to 150 C, an API SP 5W-30 would be thick enough at ~125 C, or a 0W-20 at ~117 C. If your oil temperatures are never very high, you could use a thinner grade and probably free up some power.

If you have an oil pressure gauge, you can use it to infer how much the oil temperature has risen by comparing oil pressure at idle before and after a run. Oil pressure might be expected to drop by around 10% for a 5 C increase in oil temperature.

 

[TiGeo]

AutoX just isn't that hard on a car/oil. I wouldn't think an oil cooler is necessary at all. HPL 5W30 should work just fine. My car sees 270+ oil temps on track buy at AutoX in hot summer temps 230 without an aftermarket oil cooler. I'd run that oil for a full year/AutoX season.