Engine break-in procedure= more hp (here starts the debate!)
#16
on my stroker motor, the break in was on the dyno. a few short test runs and then WOT repeatedly. greg brown from precision did the work, seems to think if you are gonna run hard break it in hard. same MO on my al holley built race bikes too. a few heat cycles and bwaaaaaaaa...
#18
Originally Posted by Matt Sheppard
Greg Brown is the MAN!
I always wonder what would happen if they met and built a race motor. a 1200chp 3.8L NA 2 stroke V8?
#19
#20
Debated, sure, but never fully understood or completely explained. Even the debate that you point to says that 300-500 easy miles are required. This is different from the original post that says to run it hard very soon after initially building it.
#21
The paradox is that on new cars there are some componants that like to be broken in easy, like camshafts, transmission gears, and other high load items. There are some that need immediate load to seat properly, like rings, and there are some that shouldn't care either way as they should not ever have metal to metal contact, like bearings and seals.
Pick your poison.
Pick your poison.
__________________
Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
#22
Originally Posted by Larry Herman
The paradox is that on new cars there are some componants that like to be broken in easy, like camshafts, transmission gears, and other high load items. There are some that need immediate load to seat properly, like rings, and there are some that shouldn't care either way as they should not ever have metal to metal contact, like bearings and seals.
Pick your poison.
Pick your poison.
#23
Ok I'm doing a PCA DE event this weekend.
Rebuilt the 924S motor using new (to the block) crank, piston rod from a #2 rod bearing failure.
New rings. Top end left alone (it was rebuilt last summer).
It's a race car so no street time to break in the engine.
We've had it idle off an on no more than 20minutes or so at a time.
Temps are good, oil pressure is good. Exhaust pressure feels very strong.
We have not done a compression test.
Because we had an oil pump fail shortly after turning it over -- we have run for a few
minutes at <2.5K rpms (prior to the failure). But we drained all the oil then and
it looked great. So in essence we've flushed the oil once already.
We also installed an oil cooler and accusump and replaced the oil pump despite ("those never fail" :-)
I've read a bunch of posts on break-in.
My plan is to run the weekend DE with a limit of RPMS to <=5K but I'm not sure I understand
light load vs 3/4 load vs full load. What does "load" mean in this sense?
I was planning on running the entire weekend DE at this 5K limit, then changing the oil in
preparation for our endurance race late July.
Guess I'll have to be patient and work on non-WOT high RPM driving this weekend :-(
thx,
Mike
Rebuilt the 924S motor using new (to the block) crank, piston rod from a #2 rod bearing failure.
New rings. Top end left alone (it was rebuilt last summer).
It's a race car so no street time to break in the engine.
We've had it idle off an on no more than 20minutes or so at a time.
Temps are good, oil pressure is good. Exhaust pressure feels very strong.
We have not done a compression test.
Because we had an oil pump fail shortly after turning it over -- we have run for a few
minutes at <2.5K rpms (prior to the failure). But we drained all the oil then and
it looked great. So in essence we've flushed the oil once already.
We also installed an oil cooler and accusump and replaced the oil pump despite ("those never fail" :-)
I've read a bunch of posts on break-in.
My plan is to run the weekend DE with a limit of RPMS to <=5K but I'm not sure I understand
light load vs 3/4 load vs full load. What does "load" mean in this sense?
I was planning on running the entire weekend DE at this 5K limit, then changing the oil in
preparation for our endurance race late July.
Guess I'll have to be patient and work on non-WOT high RPM driving this weekend :-(
thx,
Mike
#24
the best way to make more hp is to run the engine for a little while and then rehone the cylinders. In dragracing we use to make dyno hits on the motors, rehone them, two more hits on the dyno and then bombs away!!!
More importantley when starting a new engine you should use non detergent break in oil, it grabs any metals or pieces in the engine and basically gives it a good cleaning.
My theory, beat it from the beginning.
More importantley when starting a new engine you should use non detergent break in oil, it grabs any metals or pieces in the engine and basically gives it a good cleaning.
My theory, beat it from the beginning.
#25
We all know the drag racers get rebuilt engines between runs -- or at least the top end -- amazing! -- but expensive.
This is a lemons/chumps racer :-)
I don't have that kind of luxury (time or money) --
Unless something breaks -- we're not opening
this puppy back up.
Mike
#26
My 944 spec motor got new rings and main/rod beraings and I broke it in on track. I idled it a little when I first built it to warm it up and make sure it did not have any leaks.
First session out I took my laps and ran part throttle for 5 mintues and increaing rev limit. After this I went 3/4 throttle to redline, but also let off the gas and allowed it to engine brake much more than a normal lap. After a few minutes of that I just went WOT and finished the session driving normal.
I drained the dino oil in the motor after that and ran my next session at the the track like normal. That motor make great hp and nearly won a national championship with it. I am still running it now, but had to redo the head due to a shift error on my part.
First session out I took my laps and ran part throttle for 5 mintues and increaing rev limit. After this I went 3/4 throttle to redline, but also let off the gas and allowed it to engine brake much more than a normal lap. After a few minutes of that I just went WOT and finished the session driving normal.
I drained the dino oil in the motor after that and ran my next session at the the track like normal. That motor make great hp and nearly won a national championship with it. I am still running it now, but had to redo the head due to a shift error on my part.
#27
We all know the drag racers get rebuilt engines between runs -- or at least the top end -- amazing! -- but expensive.
This is a lemons/chumps racer :-)
I don't have that kind of luxury (time or money) --
Unless something breaks -- we're not opening
this puppy back up.
Mike
This is a lemons/chumps racer :-)
I don't have that kind of luxury (time or money) --
Unless something breaks -- we're not opening
this puppy back up.
Mike