as it says, i have my B18C1 block at the machine shop putting in new bearings, Eagle H rods and CP 9:1 pistons, and these will be broken in and driven for a lil while WITHOUT boost. I was wondering (and yes i searched) wat u guys recommend as far as break in goes. ive read so many different theories and get a general idea that yur supposed to give it more throttle than manual recommends, im also wondering if its differnt for either forged pistons/aftermarket rings or if its different with my low compression without boost. thanx in advance guys, go ahead and throw whatever u got out here!

 

if it is built right it will stay together.

the top dogs don't drive there 8 second monsters 1500-2000 lies,so why should you.

 

dam key board "MILES"

 

dyno breakin all the way drive the **** out of it and it'll be broken in... or broken very fast

 

let them motor warm up, as soon as you see the temp guage move GO!! (if you let it warm up to long itll wear the glaze off the walls)
take it out to a remote/empty road.
with the car in 2nd accerate (floor the gas pedal until 40ish mph) and the let off the gas and LEAVE IT IN GEAR (this is called engine breaking) until it gets down to a mph where you can accerate again.
this time go to 50 mph, then 60.
do this ~5 times. then do it ~3-4 times in third gear.
this is how i broke my motor in. compression check is +/- 1 psi across all 4 cylinders.

hope this helps

 

ok so im assuming everyone is leaning towards the "harsher" break in. Ive read crap about how the first 500 miles should never see above 3-4k, then how it shouldnt see more than partial throttle to that point too...and "llewsirc" that explanation is exactly wat im looking for, thanx...and if anyone else has experience with this or advice or anything, feel free to chime in, thanx

 

btw llewsirc, my gf is in the springs visiting her fam there, huh just thought that was interesting...anyway...so u mean on the third pull right after staring it up take it almost to redline in second? isnt that a little too high, even for a harsh break in? i really dont know, just looking to see who does wat, keep em comin


Modified by ChillOutWayne at 5:56 AM 12/29/2003

 

does it matter at all that the pistons are forged with aftermarket rings and an oversized bore?

 

Depending on ring type/material, the break in time may differ significantly.

Our rally car took 150 km's of break in time.

For my GSR with P73A0's with OEM rings, I did this.
-Warmed it up to operating temperature, then changed the oil.
-Fresh oil, found a hill, and in 4th gear from 2000rpm, load it up on the hill.
-For the next 400-500km, keep it below 4500 rpm, CONSTANTLY varying the rpm's.
-Initial compression test (500 km)
-For the next 1500 km, drive it normally, but don't bag on it too much.
-2000km, change oil, plugs, and do a final compression test. Good to go!

I did it this way because I want it to last, and I'm waiting to change my brakes f/r. Seems to be good, but it's taken 2000km to even SEE the oil on the stick. Nothing like a clean engine!

 

thanx for the reply, im gonna look into that too, im not really sure where to go with all that...i was thinkin let it warm all the way then get it moving not taking it past half throttle or above 3 at all for first 100mi or so, but ive come to read alot now that that isnt the best idea...oh well, we will see, any other opinions feel free...

 

I heard many differing opinions too. I figured I'd do it this way, and so far it has been PERFECT. These are cast pistons though.

 

yea i appreciate it alot...yea im wondering its its gonna be different at all for the forged pistons with aftermarket rings? also anyone else with different methods...

 

http://www.mototuneusa.com/break_in_secrets.htm

its a question that boggles us all

 

heh beats me

 

it boggles me too, but to see such a variance in procedure and opinion is pretty mind blowing too...ud have to think there at least is a " better way" to do it...who knows, any other thoughts?

 

pretty much im thinkin im gonna take it easier than that post says, i can see pushing the car that hard being good for it at all...any other thoughts?

 

When I build my engine I plan on breaking it in the hard way. I might not rip it straight to redline right away but I will definitely be putting it under load immediately after its warmed up.

I'd change the oil very frequently as well.

 

Under load yes, but revving it up to the moon is a bad idea. Find a big hill, put it in 4th and load it up.

 

yea im definetly go with some load, but im still very weary of taking it above 5-6k before at least 100 miles or so...and yea changing the oil is gonna be very frequent

 

I put 1000 miles on my forged pistons oversized bore buildup. I stayed under 50% throttle and 4k rpm. I'm running 10w40 and changed the oil at 300 and 1000. I think I'll start running synthetic after another 500 miles.

What does everyone use for oil with break in? Keep in mind it's winter in Chicago.

 

Regular oil for the break in period. After 2000 km's, you can change it up.

 

yea i know regular oil is mandatory for break in period...CRXLUV2, where u hang at? im only like 30 mins from u, wat u running?

 

well shes all back together as of last night, things went smooth and the motor work looked great, i started it up, let it warm a lil bit then started moving...put 20mi on and changed the oil, then put 20 more on, varying the rpm and introducing a load but all below 4K and not above half throttle...im hoping the next couple hundred go well

 

Keep the revs constantly varied! Good luck with the break in.

 

any idea if the slight rattling noise like a diesel will go away with the forged pistons? its faint but i can hear it at idle, evne after warm up