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-   -   how to break-in race motor at the track? (https://www.racingjunk.com/forums/showthread.php?t=20808)

v8Fiero 05-13-2008 10:01 AM

how to break-in race motor at the track?
 
Im almost ready to break-in my motor and start dialing it in. I am just curious though, what is the proper way to break in a race motor while its in the car at the drag strip? I want to get the rings set properly without scuffing the cylinders to death.

its the engine in my sig... 418 sbc, full roller, forged bottom end, high lift cam, planning on running valvoline vr1 20/50 oil

does this sound right:
prime oiling system
in garage start it, bring it to 3000rpm, shut down, check for leaks.
trailer it to track
first run make a slow run keeping rpms around 3000rpm with minimal throttle
second run same thing
third run slowly raise rpm in each gear (1st-3k, 2nd 3.5k, 3rd-4k) then decelerate at the end of the track in the same fasion with the engine. (engine brake from 4k-3k)
fourth run same thing
after this I am not sure how much I should push a new engine, should I keep raising the rpm and throttle until I am doing full throttle runs or should I stop at a certain point and drive it on the street for a few hundred miles before my first full throttle run?

thanks for your help. 8)

curtisreed 05-13-2008 10:19 AM

My motor is just like yours, sbc roller etc. I just brought the motor up to temp. a couple of times to seat the rings, checked everything over good, timing, carb, leaks etc. Drove it around at the track so everything had good temp. and made my first pass 6.42 1/8. I used straight 30wt Rotella to break in with. Made 3 passes and changed to 20-50w Amsoil. Car runs 6.0-6.1 now. The main thing to me is the ring seating before the first hard pass. The rings and hone job we have worked out seats in pretty fast.

Curtis

johnracer 05-13-2008 11:28 AM

I've never, and I mean never made an easy pass on a new race engine. It's always been wide open full pass from the very first. Warm it up and let it fly!! That'll seat the rings faster and better than anything else....

bjuice 05-13-2008 03:26 PM

i am with John..bring it up to temp,check for leaks and hammer down..
todays motors with roller cam shafts are not like the flat tappet cams of old where you would take out the center valve spring to start up after wiping the seating gritty paste on the lifters..

us7race 05-13-2008 06:06 PM

Same here. Warm it up good and run it like normal. I like to let mine idle for about 30 minutes on and off over a couple of sessions revv on it a little not too hard. Keep a good eye on oil pressure ect.

kwkracing 05-13-2008 07:00 PM

motor
 
same thing, check for leaks, timing, oil..... and Hammer down from day one!

itsabird 05-14-2008 04:21 AM

same here, just make sure and not get too much fuel in the cylinders, at start up, as not to wash them down. and hammer down.

gearhead1011 05-14-2008 04:57 AM

Like the others I break mine in on the track with a full pass. If it's a flat tappet cam I would break that in when it's 1st started. Along the lines of that when I go to the track I warm mine up to about 150* then shut it off and let it heat soak for about 15 minutes. This will get all the internal parts up to a fairly even temp.

v8Fiero 05-14-2008 06:10 AM

thanks for the help guys, I will probably end up doing a few runs like my first post until its warmed up to normal temp and then start dialing it in. :twisted:

cepx111 05-14-2008 09:48 PM

Something I always do is after I've done the initial start up and warm up ETC.
I'll drain the break in oil right away it's usually gets pretty nasty quickly and then cut the oil filter open and do a lookie loo inspection to make theres not an abnormal amount of metal in the element.
Then after I've giving everything the green light I'll pour in some fresh oil install a new filter then its hammer time.
Charles


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