so im buying a completely rebuilt s4 short block with an agressive streetport, gonna be slapping it together and puttin in my car asap. but i was wondering, what is typical/safe miles to break in a rotory? i know with piston engines its around 500 miles... same for a rotory?
thanks

 

anybody?? did i post this in the wrong section or something??

 

You will get all kinds of opinions. As long as its not a totally brand new engine, a good 4 heat cycles and your fine. After that I break mine in on 30lbs of boost on the dyno

 

If the bearings are new, then be sure to break it in with low rpm and load for 1000+ miles and 3 oil changes.

I like to break in all the engines I build, 100% new or just a seal replacement. Though, sometimes it is impossible depending on the application.

-J

 

He's tooootallly wrong...65psi and your gold

 

I've always had the best compression on piston and rotary engines by a slow break in progress with low rpm and low load for about 500miles. I realize that on race cars this is almost impossible so in that case I would just do what Ernie recommended for race car applications.

 

Yeah, your right...I am a smoke blower

-J

 

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

i found this interesting a while back when i was linked to it, might give you some ideas. i don't totally agree with it but the logic is on the mark.

if you have new bearings id do a few good long drives. let it warm right up to full water and oil temp. keep the boost out of it, and load it up and pull through the gears, no more than 4-5krpm. fully cool to room temp and start again. if the bearings are old. dont waste your time.

heat cycled 4-5 times, then tune to kill

break in as a concept is dumb, if **** is out of tolerance and needs to *wear in* its junk to start with and will fail anyway. things will seal up, being a baby wont help it. things seem to seal up better with more load in the first few hours of run time. but that's just me

 

You're right, it is just you. "****", eg bearings, even when in "tolerance" are a ware item and is a TOLERANCE FIT and should be broken in properly.

 

+1

 

one mans "properly" and other mans "properly" are always going to be different. you have your ideas and i have mine. im well aware they are a tolerance fit, you should note i suggested a short break in for bearings was required. but our opinions are different on the extent that is required, but your the pro

in the next few weeks ill be opening a block. it had new bearings in it before the previous strip and inspection, on the new bearings it did a handfull of heat cycles and hard low rpm pulls then straight on the engine dyno for 28psi(no chassis dyno). went into the car, got flogged and flogged till one seal got a little banana shaped from high egts on the burnout track. pulled it down to inspect, bearings looked asif they hadnt even seen any work. put it all back together again. warmed it up and tuned straight back to 30psi. 9500rpm unbalanced, oh the horror

what do you think will happen if you dont give it enough time to run in time? im open to learn