What kind of oil you guys use?
I was wanting some info on doing an oil change. Ive worked on for a few years now but never an RX7. Im actually a mechanic on Army Tanks for the military, I didnt want to start off on the wrong foot trying to change my oil. Also wanted to info on what kind of oil to use. I called Pettit Racing today cause their the ones who built my motor and I wanna say they told me to run 20 50 but I cant remember I was on my cell so it wasnt totally clear. Just wanted to see what everyones input is. Thanks.
this is one of those questions that depend on who you ask...
I myself have used Mobil 1 synthetic 20/50 for a few years no problem. Actually when I switch to it, the engine did feel a little smoother and it even picked up a full inch of vaccum.
I just finished putting my engine together and for the first start up I'm using Mobil non synthetic 10/30 but I will be switching to a heavier oil later on after break in.
I myself have used Mobil 1 synthetic 20/50 for a few years no problem. Actually when I switch to it, the engine did feel a little smoother and it even picked up a full inch of vaccum.
I just finished putting my engine together and for the first start up I'm using Mobil non synthetic 10/30 but I will be switching to a heavier oil later on after break in.
Joined: Mar 2001
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From: FL-->NJ/NYC again!
this is one of those questions that depend on who you ask...
I myself have used Mobil 1 synthetic 20/50 for a few years no problem. Actually when I switch to it, the engine did feel a little smoother and it even picked up a full inch of vaccum.
I just finished putting my engine together and for the first start up I'm using Mobil non synthetic 10/30 but I will be switching to a heavier oil later on after break in.
I myself have used Mobil 1 synthetic 20/50 for a few years no problem. Actually when I switch to it, the engine did feel a little smoother and it even picked up a full inch of vaccum.
I just finished putting my engine together and for the first start up I'm using Mobil non synthetic 10/30 but I will be switching to a heavier oil later on after break in.
I use Idemitsu oil, you can get it from rx7.com, it's on their website. It's not cheap, so daily driver guys should probably choose something else.
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I use your basic, off the shelf at any store valvoline 10w-30. The white bottle with the blue label.
I might switch to something really good by summer, prob idemitsu like someone mentioned. See how that goes.
I might switch to something really good by summer, prob idemitsu like someone mentioned. See how that goes.
I have been using Valvoline 10w-30 for 9 years now. Not sure what I'm going to use, once I get the car back after the single turbo conversion.
Finally! some sophisticated scienctific thinking applied to this endless debate. Thanks for your post. I've read substantially the same thing from other sources. The number of backyard engineers who routinely dismiss the recommendations in the owner's manual never ceases to amaze. Everyone with an interest in this topic should read the article to which you've linked.
I had my oil tested 4 times at Southwest Spectro Chemical in my FD starting in 1998 when the car only had 36k miles or so. I changed the oil every 1500-2000 miles and it always came back with 10% fuel dilution.
....and what, the engineers who designed the car didn't know about fuel dilution in rotary engines?! LOL! Read the article linked above by rearviewmirror and learn something.
Joined: Mar 2001
Posts: 30,804
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From: FL-->NJ/NYC again!

Edit: Also, the manual is aimed at stock, 255 hp FDs, and I highly doubt the engineers who designed the car envisioned FDs with double the stock horsepower routinely touching the redline
While there is a lot of good info in the ferrarichat forum gentleman's long post, he does gloss over the fact that motor oil and its applications to various engines is an extremely complicated subject, one that can't be covered with in a lengthy posting that tends to impress with tons of viscosity measurement results. (I also take issue with his assertion that the API SM grade oils are automatically superior to previous API grades-- the increased cam lifter wear that many classic hotrod builders were seeing with off-the-shelf API SL oils comes to mind-- but no reason to belabor this subject).
There's no doubt that rotaries' fuel dilution is far greater than that encountered in piston engines', and piston engines don't have internal stationary gears (responsible for transferring power) that shear on the motor oil molecules in a way that cams/lifters can't approach. There's too many variables to draw conclusions based simply on some research made with regards to conventional piston engines.
For a novice such as myself, this question about what oil to use is just plain confusing. The issue of fuel dilution is the one that has me worried. I know that atkinsrotary recommends on their website the use of 5W-30 or 10W-30 in the winter and 20W-50 in the summer. Of course, Atkins is located just a few miles from me. Both our winters and summers are mild. Cold here is typically in the 30's and Hot is only in the 80's, and that is rare.
The very experienced rotary mechanic I had check out my FD used 10W-30 Quaker State. When I changed my oil again after taking out a Greddy Oil Filter relocation kit I used Penzoil 5W-30. Come springtime, I'm considering changing out to a synthetic. The question is what weight to use at that time. 20W-50 seems pretty thick when the typical temperatures are still going to be in the 60-70's even in the warm months.
Thoughts?
The very experienced rotary mechanic I had check out my FD used 10W-30 Quaker State. When I changed my oil again after taking out a Greddy Oil Filter relocation kit I used Penzoil 5W-30. Come springtime, I'm considering changing out to a synthetic. The question is what weight to use at that time. 20W-50 seems pretty thick when the typical temperatures are still going to be in the 60-70's even in the warm months.
Thoughts?





