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trackcar only motor breakin...

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  • trackcar only motor breakin...

    Fourth of July is not over yet. Let's have some TrackHQ fireworks. How do you break in your trackcar only motors if you can't drive your car on the street? I would like to hear On-track methods or engine dyno or chassis dyno including break-in oil, conventional oil, and synthetic oil use during breakin and for the rest of motor's life. Let the fireworks begin...

  • #2
    break in oil, warm it up, then drive it like you stole it. After an hour or so of that, change the oil. Done.


    • #3
      Ptetty much what Rob said. You will do more harm by putting too little load/revs/heat into a new motor than by doing it to soon. The exception might be an engine built to 25 year old OEM specs .
      Such an engine will have looser tolerances and might take a few more hours to seat the rings. Race engines built at anytim or OEM engines from the last 10 years or so are built to super tight tolerances and can generally be pounded on right off the bat.

      Our OEM and race engines see something like this.

      OEM get whatever oil the factory put in. No redline or full load for firsy hundred miles then its game on. Swapped at 3k miles for same. Swapped at 6k for Amsoil street oil. Less Zinc in street oil to preserve cats.
      My new cars all run OEM viscosity except the C6Z which runs 10w40.

      Race engines get Amsoil BR30 (30w break in) for an hour or so. Never run on ttack at full load or dyno on break in oil. Switch to race oil then go. Usually 10w30 Amsoil Dominator..

      My previous and new Ram Cummins got OEM oil for 3k. Swapped for dino oil until 6k then switched to Amsoil synthetic which gets swapped at 6-8k miles.

      Aside from their cost I never understood why people race them.
      But obviously I just dont get it. -fatbillybob


      • #4
        I've never owned a new car, so I can't tell you what I do with them. My wife gets all the new cars. She just drives it and has it serviced according to factory procedure.

        For my last race engine, I took the car to a track day and ran it with conventional mineral oil, not break-in oil, if I remember correctly. First session I rant it up to 5,000 rpm. Second session 6,000 and then pretty much race pace.

        According to everything I've read, the objective of the break-in is to get the rings seated and the best way to do that is to vary the rpm greatly when you first run the engine, and to accelerate and decelerate. The up-and-down with the throttle and rpm scuffs the rings properly. On acceleration, the tops of the rings see a load and wear in. On deceleration, the bottoms.

        After that one track day, it was game on. The motor has been fine since, and it even overheated a bit early on. It's getting a bit tired now and oil consumption is beginning to rise, so it's time to do it all over again.


        • #5
          One other thing to note, expect some mild blue smoke for part of the break in period. Usually nothing to worry about. Then at some point during the first hour, the smoking will stop.


          • #6
            how do you deal with breaking in a new engine when you still need to dyno tune it?
            Also would the power change after a few hours of breakin?
            1991 Miata - Trogdor SuperMiata
            2011 Ram 2500 - all the torque


            • #7
              Originally posted by b3d3g1 View Post
              how do you deal with breaking in a new engine when you still need to dyno tune it?
              Also would the power change after a few hours of breakin?
              I'd be inclined to get an average/safe tune on it and get it on the track for break in, then revisit the dyno after a few hours of track time to tune for power.

              You could probably get it to break in on a dyno too if you keep doing pulls.


              • #8
                You're right, OP, virtually everyone will have their own opinion on this one. My own is that you largely want to drive it like it's going to be driven - with perhaps the exception being the first 5-10 minutes. During this time, I would strive to do high loads without high rpms (but never lugging). As an example, third gear at 3000 rpm and ROLL on to WOT throttle until a couple K before redline. Then, as importantly, let engine de-cel without an abrupt transition (neither slam the throttle open or closed).

                Interesting point about non-dyno tuned (new) engines. We will break in new engines on the dyno so that we have a controlled environment in order to validate a/f's. Emphasis is on break-in and the early minutes of engine life, so only making sure on A/F's and not going to redline or looking for peak power - but striving for load followed by decel.

                Personally have never believed in or used special or different oils during break-in (nor do any of the OEMs these days). Respect the opinon and practice of those that do - just never seen any compelling evidence one way or another and increasingly a subscriber to OEMs know best.

                Perhaps my only contribution to the thread is to not forget about the importance of decel. Secondly, a heat cycle or two (easier on the dyno) is not a bad thing.


                • #9
                  First thing I need to do with a new engine is get it dynoed for classing. So I do that with breakin oil then fill it with real oil and drive it normally.

                  That initial set of dyno runs does generate quite a lot of fluff on the magnetic oil plug.


                  • #10
                    While I have rebuilt, including machining, about a dozen motors Ferrari, Chevy, and Datsun, all were street motors broken in on the street. I have only broken in 1 stock oem LS6 motor in my racecar. I was unsure about racing on break-in oil and whether I was going to have time to change oil. Break-in oil seems to be all about being “conventional oil”and having enough ZDDP for its anti-wear property while still allowing wear-in and ring seating. On track we run no cats. So my 1st oil was proper viscosity conventional diesel motor oil which has ZDDP at break-in oil levels. SCCA is not a lot of tracktime.

                    So I ran it 1st time at Homestead going about as fast as I could while trying to figure out this new track and keeping an eye on oil pressure and oil temps which means even an attempt at my 10/10ths would be way below that. Then qualy later acted like a heat cycle where I could run faster but still sucked trying to figure out the track. Then I raced. My engine saga doing a rebuild was already a PITA leaving no love for my Z06. Then after qualy my starter motor died and being lazy I never did disable the clutch switch which meant I could not push start the car! After putting a new rebuilt starter in there I had even less love to change the oil so I raced it on Sunday and beat the living snot out of it. Maybe a total of 150miles on the engine.

                    Thankfully I was seeing just a few oz. of blowby oil in my catch can. "Racing" oils are missing the “street oil long life additive packages”but have lots of ZDDP for anti-wear. Like all of you we change our oils frequently compared to the months that go by in our daily drivers. At the next race in Sebring, I decided to stick to running conventional diesel oil doing an oil change for pennies because conventional diesel oil is so cheap and I was still pissed at all the work I had to do to this once “gas and oil” only racecar. One of the amazing things about my 1st LS6 motor in my Z06 was that it used no oil! I could race the weekend and not need to top it off. I did not need catchcans while many people did. Not using or needing catch cans in a Z06 is pretty rare. Most will say I'm lying.

                    So for laughs and grins I continued to use conventional diesel oil and at about the 5 race weekend (about 800miles) magic happened. I continued to monitor the blowby in catchcans. I noticed it getting progressively less with each race. In fact I ran the car super hard above my usual pay grade at CoTA starting 43rd missing qualy finishing 7th catching and passing half my class, and no oil was in my catchcan. I was running the car hard. It has been 1 race weekend since CoTA and still no oil in the catchcan. So when do I switch back to manufacturer prescribed synthetic oil? IMO my break -in wasn't completed in that 1st hour of running. I'm thinking that our track motors may not be reaching their prime sealing until more miles/races are on the motor. In fact I'm thinking going to synthetic oil too soon is possible.

                    At this point, I think my motor is now ready for synthetic but if I do I will use synthetic diesel oil which is way cheaper with nearly the same ZDDP and even some streetcar beneficial additives that racing oils lack. On the other hand, I may just stay with conventional diesel oil since it is even cheaper and I change it so dang often. Since oil change interval is not an issue I can only see thermal breakdown resistence as the only synthetic advantage. Thermal breakdown of oil shows up as viscosity breakdown which can be seen on your Blackstone oil tests. So far conventional diesel oil is holding up.

                    So how do you guy know your motor is broken in?


                    • #11
                      Agreed on Cooltech's adamant point about decel, helps set the rings and VSS.

                      I lost a rebuilt motor quickly from lugging it. Didn't realize the fuel relay was flaky, kept trying to get it to run right. When it did, it chunked the #3 rod bearing 1/2 way through it's first angry lap. No new inspection ports created. The next motor, I used conventional oil for early and often, switched to better oil after everything checked out.
                      Yer pal,


                      • #12
                        Sounds like you are on to something fatbillybob and if I had the same experience as you, I'd probably try to repeat the previous success. Do that 50- 100 more times and it may start to become statistically significant - and then I would try it

                        On a more serious note, I'd think that my motor was broken in when I reached a steady state on both oil consumption and catch-can results - crossing my fingers that steady state was as near zero as possible.


                        • #13
                          Originally posted by CoolTech View Post
                          I'd think that my motor was broken in when I reached a steady state on both oil consumption and catch-can results - crossing my fingers that steady state was as near zero as possible.
                          Yes! This is what I am thinking. I think that we tend to just do things others tell us like 1 hr on break-in oil, change and go. I think break-in may take longer than we think and monitoring oil consumption and catch-can results can give us a reason to call a motor broken-in especially when ultimately people want to use synthetic oils. I have it from experience that a rebuilt motor will not break –in on synthetics and no amount of break-in oil or conventional is going to get rings to seat that haven’t 1st seen some kind of conventional oil first.

                          Now before anyone says GM’s vette comes with synthetic oil and you break the motor in on it, I don’t believe it. No one knows except GM what kind of oil is the 1st oil. They only tell you to use synthetic spec oil in the future. They also use this break-in method below that 90% of high performance people don’t believe in.

                          <<For the first 800 km (500 mi):
                          . Avoid full throttle starts and abrupt stops.
                          . Do not exceed 4000 rpm.
                          . Avoid driving at any one constant speed, fast or slow, including the use of cruise control.
                          . Avoid downshifting to brake or slow the vehicle when the engine speed will exceed 4000 rpm.
                          . Do not let the engine labor.
                          Never lug the engine in high gear at low speeds. With a manual transmission, shift to the next lower gear. This rule applies at all times, not just during the break-in period.
                          For the first 2414 km (1500 mi):
                          . Do not participate in track events, sport driving schools, or similar activities during the first 2414 km (1500 mi).
                          . Check engine oil with every refueling and add if necessary.
                          Oil and fuel consumption may be higher than normal during the first 2414 km (1500 mi).>>


                          • #14
                            I think you give too much credit to synthetic oil's lubrication properties. The key differentiation from conventional oils is that synthetic resists breakdown much better than conventional oils. This is the reason for the longer service life - which is now largely dictated not by breakdown but by "normal" contamination. As such, synthetics are fine for break-in IMO. And although you have trouble to agree the factory oil fill on the Corvettes, Boss 302s, Ford GTs, GT350's are all synthetic.


                            • #15
                              I have to say, I'm with Rob on this one. All my race motors in motorcycles. Warm up, Then run it like it's going to be run at running temp for about 20min. 2 tanks of gas, with the same process. Look at/in your filter,Change oil and your done.

                              Break in oils? I have Not really seen a difference.

                              No Synthetic for break in. Or it will never.. (Found out the hard way on two motors). It's just to slippery and will not seat the rings. And BillyBob is right. It doesn't seem to ever. Now, I will say that this information was attained in the late 80's. There is many new martials being used in rings. So this may not hold any merit. But I will still stand by it (till someone shows me different)and so do all the engine builders I know.

                              All my Pro built motors have come dyno'd tune and broke in.

                              Rotary's are some what different. As the oil for the sealing is (for racing) pre-mixed with the fuel. Bean oil seems to work best or breaks in quicker (at what point you get highest HP).
                              But that also depends on the seal type. Carbon vs. Ceramic

                              This is just what I have experienced for myself.
                              That's not a Typo, I just can't spell no so well.