Breaking in a race engine?

-
doogievlg

doogievlg

Well-Known Member
Joined
Nov 13, 2007
Messages
8,381
Reaction score
2,387
Location
Amelia, Ohio
I rebuilt my motor and it will be about 80% race motor. I did the cam break in but what now? Do I take it for a few spins on the street first or wait for the track?
 
If it's only 80% race I would pull out of the driveway but only for a few minutes ;) lol
 
The car is street legal other then the exhaust and quick time pro slicks. I'm going to try and get a few miles on it just to make sure nothing pops up at the track.
 
nothing wrong with a few blasts down a country road. testing 123 .
after all you only have the old 3/4 race setup.
 
you have broke in the cam now you need to seat the rings. I like to go just fast enough it wont lung in third and then pull up to about 60 then back again, do that three or 4 times and your ready for the track
 
I have about 2 miles of two lane 55 mph road between my shop and a state park. Tomorrow I'll take it out and give it some good pulls then head over to the dam and give it the beans.
 
doogievlg said:
I have about 2 miles of two lane 55 mph road between my shop and a state park. Tomorrow I'll take it out and give it some good pulls then head over to the dam and give it the beans.
Click to expand...



you're going to chew those Quick Time Pros all to pieces on the road. I've been there and done that. just normal driving on the road at speed will eat them up.

you do whatever makes you feel best about the situation, but you don't have to take that engine for a spin down the road.

all we do is break the cam in and let it cool overnight on its on. the next day we will crank it up and set the idle at about 2,000 rpms until it warms up. we get it to about 180 to 190 degrees and back the idle down to about 1,000 to 1,200 rpm wiht the water pump and fans running. after about 5 minutes at that temp, we shut it off and let it cool down on its on without the pump and fans running.

then when you get to the track, run the rpms up and let the car coast back down as you are driving it around warming it up.

then beat the piss out of it from there on out. have never had a problem doing it that way.

good luck.
 
I took it out. Did some good pulls to about 70. First started at fifty then thirty then twenty and finally from a stop. Motor pulls hard in the 40 to 70 range but wasn't really getting out of the whole like I would have liked. Non the less the car ran great and temps stayed right around 180!
 
805moparkid said:
you have broke in the cam now you need to seat the rings. I like to go just fast enough it wont lung in third and then pull up to about 60 then back again, do that three or 4 times and your ready for the track
Click to expand...

Yep.

fratzog lover said:
Babying the rings at break in is an old wives tale.
Click to expand...

I must be an old wife then , but I learned long ago that you want to seat the rings in acceleration and deceleration for a motor that will see street time.
It takes less than five minutes and I have never had oiling or compression problems in any of the motors I have done this with.
Three or four trips up to highway speed and let off to roughly half that speed...........firm but not flat footed back to 65-70.
Then flog the **** out of it.
This has been my recipe and has worked for neigh on a decade in one motor and several years in others that ran well when I got rid of them.
At a minimum , I sure didn't hurt anything by doing it. :burnout:
 
tubtar said:
Yep.

I must be an old wife then , but I learned long ago that you want to seat the rings in acceleration and deceleration for a motor that will see street time.
It takes less than five minutes and I have never had oiling or compression problems in any of the motors I have done this with.
Three or four trips up to highway speed and let off to roughly half that speed...........firm but not flat footed back to 65-70.
Then flog the **** out of it.
This has been my recipe and has worked for neigh on a decade in one motor and several years in others that ran well when I got rid of them.
At a minimum , I sure didn't hurt anything by doing it. :burnout:
Click to expand...
I always did the same thing.....and had the same results as you tubtar. :thumleft:
 
I am nervous as hell. The car doesn't seem as quick out of the hole as I expected and if I didn't pick up a good amount of time I'll be seriously seriously disappointed. I expected to feel a huge difference when I went to flat tops and aluminum heads but I'm not feeling a huge improvement!
 
Don't fret doogie. As long as the cam break in went well, and she's sealed, some tuning will get ya' running strong.
 
I've been doing nothing but worried. I seem to remember being able to floor it from a stop and spin the tires real good. Now I romp it and it will spin them for about twenty feet. Could this be because I took around 100 pounds off the front of the car. Now it's hooking better? With street tires!
 
I don't remember your exact combo? Engine wise I believe your 360 has the new Eddy's, flat top pistons, a .484 purple cam, a Performer intake, and a 650ish carb. I thought you may have asked at some point about upgrading from a 7.25 rear? Give us some info on the rear gear and the converter stall speed, along with any other info that may help some of us help? What type of exhaust system (header size) wouldn't hurt either. :D
 
360 .30 over
Eddie heads
Performer rpm intake
Speed pro flat tops
Mp .484 cam
Hooker headers with a 3" collector

727 with b&m flex plate and a converter that flashes at 3000

8 1/4 with 3:55 gears

Best time before without the heads and pistons was 14.2 @ 96 mph with street tires.
 
If I'm not in low 13 or high 12 range now then I screwed up bad and will be taking a break from the hobby.
 
You must log in or register to reply here.
-

Back
Top