Is there a correct break in on a re-ringed engine?

[wh23g3g]

Ok I like to get all the opinions as possible on my break in of my big block 400 in my 73 Charger. Eventhough this is a Slant Six column, I'm sure some of the tech probably applies to all these Chrysler engines. I'm almost finished up with my 73 Charger and then it will be ready to roll it outside and initially fire it up and do the "cam-break in". The engine ran good when I got the car 5 years ago and I've slowly been doing everything to the car. Facts about this motor are it's a 76 400 passenger car block .040 over, .010 over on the crank. What I did to it was have the block cleaned, crank polished, honed block, new cam bearings, and a Speed Pro Cam put in. It's a .458/.460 lift which according to Sealed Power was the factory replacement. I put a new HP Melling Oil Pump, Milodon stock replacement pickup, Mopar Performance Windage Tray, Sealed Power .010 over bearings, Cloyes OEM replacement timing set, new Elgin 400-4BBL stock replacement springs, reconditioned 73 heads with 3-angle valve job, stock 73 400-4BBL iron intake, 73 HP exhaust manifolds, Reman TQ 4BBL, and stock Reman distributor. So I've read about many different intial break in procedures requiring the engine to be revved to 2000RPM for 15-30 MINS. I've read procedures that say add a quart of Mopar Crankcase Conditioner let the engine idle until warm and take it out and accelerate from 30 to 50MPH 10 times. Some old timers have told me about the 2000 RPM deal and then some have told me just start up and let it get to operating temperature and just get it running good. So who's exactly right? The cam instructions do say rev it to 1800RPM for 15 mins, but the ring set instructions say to load it up from 30 to 50 MPH 10 times. But if that is both correct what do you do first? My barber who has built race motors, stock motors, and even fabricate hot rods says just put some good oil in, an additive, crank it up and let it get to operating temp and make sure it runs good. He said back when they were building these cars the manufacturers didn't do all that when the cars were built. He said they just put oil in and fired it up. So is there a correct way? It's my first rebuild so everything could go wrong, but it just sounds like starting it up and revving it up to 2000RPM right away would be destructive. What's the theory behind that?

 

[66aCUDA]

Cam first then follow ring manufactures recommendations. I like to vary the engine speed up and down frequently on a street engine. No prolonged steady speeds for the first 500 miles (5 minutes or more). THIS IS FOR PLAIN CAST RINGS. The new metric ring packs dont need this.
MHO
Frank

 

[805moparkid]

well what ive been taught by many race engine/street engine guys is to prime the engine to get oil pressure, whether cranking with no plugs in or with the tool. then get it running and take it up to nothing below 2K for 30mins, all the time watching your oil pressure and water temp. after 30 mins back it down to 1K idle and shut it off. let it get stone cold again, and then run it above 2K again (2K-2500rpm) for 30 mins. then drain the oil, check everything out, check cyl pressures. they might not be what u expect but she is new. tune the carb and timing. then take it to the free way and drive at 55 for 20 mins then 65 for 10mins, back down to 55 for another 10 mins, up to 75 for 10 then back down to 55. park it and let it cool down. chk everything. u DO NOT want to get into stop and go traffic while doing this. change the oil after cam break in, 500 miles, 1000 miles, 2000 miles, and then every 3K or 2500 like i do. u a good filter like a WIX(Napa Gold) or K&N.

 

[2 Darts]

I'm going to recommend a hybrid of what the other two posts have said with a few tweaks.

1. The engine oil supplement needs to have a ZDDP (zinc) additive in it for the lifters to break in properly. Do not overfill.
2. Prime oil system before lighting the fire.
3. Fire it up, check for leaks, and bring to normal operating temp.
4. Shut-down, let cool, re-check head bolt torque (in sequence, please). Button everything up.
5. Ready to drive. NO WOT for first 500 miles! Vary engine speed every 5 minutes or so to allow proper ring and valve break-in. IMO don't take the engine over 2500 rpm in the first 500 miles.
6. Change oil and filter at 500 & 1000 miles. Put on your normal schedule for engine fluid service after the 1000 mile change.

It's great to be coming down the home stretch finishing up. Good luck.

 

[slantzilla]

Last new motor I put in the red car I fired, let idle for 20 minutes at 2000 to break the cam in, drove 6 blocks, and hit it with a 100 shot of nitrous to get everything friendly.

 

[805moparkid]

Last new motor I put in the red car I fired, let idle for 20 minutes at 2000 to break the cam in, drove 6 blocks, and hit it with a 100 shot of nitrous to get everything friendly.

well depending on the rings sometimes that is what u have to do! i know that some diesels they have to put them on a dyno and wot them till they have no more black smoke!

 

[66aCUDA]

On 2 Darts post....You cant prime the slant 6 oil system like you can on a V8 so skip that part. The best you can do is take the valve cover off and pour oil down the lifter bores.
But a lot of this is unnecessary because the original poster said "re ring" only.
Frank

 

[wh23g3g]

Well this is a 400 big block, just new stock cam, hastings plain cast rings, sealed power cam, rod, and main bearings. I think I'm going to fire it up and make sure it's running good enough and raise it up to 2000RPM for 20-30 mins and shut it down. I know there shouldn't be any surprise coolant leaks or fuel leaks. The oil leaks you can't ever be sure of, especially the rear main. We did the best we could to seal it and it shouldn't leak. I torqued everything down on the engine to the proper torque out of the 73 Chrysler service manual using a new Craftsman torque wrench that I only used on this engine.

 

[Shaker223]

Last new motor I put in the red car I fired, let idle for 20 minutes at 2000 to break the cam in, drove 6 blocks, and hit it with a 100 shot of nitrous to get everything friendly.

I agree...break'em in hard

 

[Babyblue66]

Break the cam in for 20 min as suggested. Check over everything and go run it hard a few times. Seals the rings. The only way I have ever done it. Just like they do on the dyno!