The Mustang Forum for Track Enthusiasts

Track Mustangs Online was built specifically for those who track their Mustangs!

So how do YOU break-in your off road (race) motors?

honeybadger

TMO Race
238
169
TX
Curious to hear how folks are breaking-in motors that never touch public roads. Will be getting back my motor back from Tim soon and curious to hear what others do. First go round, I did the typical dyno seating of the rings and then we sent it:

Do Three 1/2 Throttle dyno runs from
40% – 60% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

Do Three 3/4 Throttle dyno runs from
40% – 80% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

Do Three Full Throttle dyno runs from
30% – 100% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

What does everyone else do? Please define if OEM motor, crate motor, or blueprinted race engine :)
 

PatrickStapler

TMO Advanced
115
92
Huntsville, AL
HPDE
3-5 Years
We broke my engine in for 30 minutes at 2K RPM on the dyno. Never shut it off. Did the first pull and shut it down. Set the timing to race conditon, made the initial primary and secondary jet changes and started making additional pulls each one with successive jet changes until the primary and secondary flows were as balanced as they could be to one another. Eight pulls later we were done.

All this may be completely useless to how you break in a newer style engine.
 

honeybadger

TMO Race
238
169
TX
We broke my engine in for 30 minutes at 2K RPM on the dyno. Never shut it off. Did the first pull and shut it down. Set the timing to race conditon, made the initial primary and secondary jet changes and started making additional pulls each one with successive jet changes until the primary and secondary flows were as balanced as they could be to one another. Eight pulls later we were done.

All this may be completely useless to how you break in a newer style engine.
Sounds like you're on an engine dyno? I've love to do that, but will be on a roller since I have a 5.2
 

JDee

Ancient Racer
1,030
915
halfway between Mosport and Shannonville
W2W Racing
20+ Years
This goes back a long way, late 80s early 90s, not sure it's relevant these days, there were no chassis dynos back then that I ever heard of. For my endurance engine the builder wanted the ring seating to be perfect. When the short block was ready he had a rig that he could put an assembled short block (with oil pan and oil) onto. It would be turned by an electric motor for about an hour. This seated stuff nicely, though with totalseal rings it didn't put much if any visible wear in the bores. Once in the car he specified putting nothing special oil in it and not getting it real hot, he wanted some friction. Then after a gentle complete warm up do five cycles of accelerations from 30 to about 70-80 mph and then lift off the throttle totally and let the engine bring the car down to 20 mph or so, each cycle with progressively more throttle from maybe 40% throttle on the first pass to wot on the last one. Bring it back to the shop, put the race oil in and go race it. Never had a problem with one of his engines and they always made good power. These were turbo 2.2 litre 2 valve Chrysler engines.

I haven't built a race motor in a long time, hope not to have to but one never knows....
 

Hangman77

TMO Intermediate
51
33
West palm beach
HPDE
Under 3 Years
Doesn’t take much to break in newer engines. Especially built race engines.
Usually I run a baseline tune. Put around 50-70 miles on the car without wailing on it. Make sure it’s run through the rpm ranges pretty easy. Build up intensity while driving, check fluids. Check for any leaks.

then dyno it to the power level you want. Then time to beat on it.
 

JAJ

TMO Addict
888
826
In the V6L
Curious to hear how folks are breaking-in motors that never touch public roads. Will be getting back my motor back from Tim soon and curious to hear what others do. First go round, I did the typical dyno seating of the rings and then we sent it:

Do Three 1/2 Throttle dyno runs from
40% – 60% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

Do Three 3/4 Throttle dyno runs from
40% – 80% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

Do Three Full Throttle dyno runs from
30% – 100% of your engine’s max rpm
Let it Cool Down For About 15 Minutes

What does everyone else do? Please define if OEM motor, crate motor, or blueprinted race engine :)
Back in 2019, I was at the Ridge for one of the 14 track days I did that year. It was one of Tom's days, so I guess it wasn't really a surprise when Randy Blaylock turned up. He unloaded one of his race cars from the transporter and ran with the HPDE guys through the morning. Turns out he was breaking in a new race engine, and running at our pace was the perfect way to do it. That motor sounded awesome, by the way.
 

honeybadger

TMO Race
238
169
TX
Doesn’t take much to break in newer engines. Especially built race engines.
Usually I run a baseline tune. Put around 50-70 miles on the car without wailing on it. Make sure it’s run through the rpm ranges pretty easy. Build up intensity while driving, check fluids. Check for any leaks.

then dyno it to the power level you want. Then time to beat on it.
WOuld love to get it on the road, but it's not even registered. So offroad only for me (dyno or track).

Back in 2019, I was at the Ridge for one of the 14 track days I did that year. It was one of Tom's days, so I guess it wasn't really a surprise when Randy Blaylock turned up. He unloaded one of his race cars from the transporter and ran with the HPDE guys through the morning. Turns out he was breaking in a new race engine, and running at our pace was the perfect way to do it. That motor sounded awesome, by the way.
Any idea if it was broken in on the dyno beforehand? I'll be using the first couple sessions at COTA in March to complete the break in, but assumed getting it on a dyno for the initial run after the first start was recommended over going straight to the track. But maybe that's not necessary if you're already tuned correctly.
 

JAJ

TMO Addict
888
826
In the V6L
...Any idea if it was broken in on the dyno beforehand? I'll be using the first couple sessions at COTA in March to complete the break in, but assumed getting it on a dyno for the initial run after the first start was recommended over going straight to the track. But maybe that's not necessary if you're already tuned correctly.
All he said was that he had a new engine and he was putting some time on it before racing it. The builder probably did whatever the builder usually does, but we didn't talk about that part of it. He'd go out, run a handful of laps (that didn't take long ;)) and come in and dig around under the hood for a bit, then go out and do a few more laps. I got the sense it was part of a careful and thorough process to make sure all was well.
 

Hangman77

TMO Intermediate
51
33
West palm beach
HPDE
Under 3 Years
WOuld love to get it on the road, but it's not even registered. So offroad only for me (dyno or track).
one of my builders always told me, you can break it in on the Dyno and just go race it. Of course just run an easy track day with varying intensity to get some datalogs. Make adjustments and then keep going.

Tim builds stout engines. I’ve been running my whipple terminator for 8 years now at mid 700whp And that engine hasn’t had a hiccup. Also have my dads 96 cobra with a MPR engine for like 9 years on a YSI and now a pro charger. Runs like a clock.
 

bob

TMO Race
301
185
sfo
I break all motors in the way the motor will be used. I do what motorcycle guys do. They wail on them at 1st turn of the key to seat rings and bed in parts the way the motor will be used.

Today's motors seem to have PCV catch can issues where those using OEM motors for clubracing have real issues with blowby oil being sucked in the intake. Thus the catchcan is born. Some use them on both heads of a V8 sometimes just one. I think a well built OE 1st motor that came with the car is often the best motor. A crate motor is second best and a rebuilt motor is nearly always questionable. Many talk good game but can't deliver. We see this in among other things extra oil in catch cans and motors with short lifespans, and motors that blow up on track (which are always our fault).

Just in the last 15 years my many motor experience has been with GM LS motors and now Coyotes. I can tell you that either of these motors can be properly built and broke in like you use/race them and they will use no oil. This is a mustang race forum. Break in on track like you would race the car. That's what motorcycle guys do. They do not subscribe to the gentle breakin techniques we read about...constant rpm varied rpm like throttle etc etc. I'm living proof of taking a brand new Coyote 1 motor in the car and just beating on it from day 1. I drove the car home from the dealer one weekend then next weekend to the race track and floggled it. Drove it home and gutted the car out and welded my cage. My 100% race only 2019 S550 uses zero oil. I ran a race weekend at Autoclub speedway and got a sudden invite to race at CoTA. I put my car in that guy's trailer and raced CoTA 2 weeks ago and still put no additional oil in the motor. I got about 1000 miles on the motor all qualy and race. It will get a 3rd race weekend next week at Buttonwillow when his trailer comes back from CoTA. I plan to just add gas and new tires.
 

TMO Supporting Vendors

Buy TMO Apparel

Buy TMO Apparel
Top