ok i have a new gm preformance engine that is brand new and my engine will be done soon and i am wondering how to break it in. should i let it idle for like 15 minites before i move it. This is from a article about breaking in your cam and i would amagine that you would have to do this too, keep it running between 1800 and 2200 rpm for a minimum of 18-20 minutes, varying the rpm between that range so that oil is splashed on the cam completely, that is how you break in the cam and i dont think it is broken in, so do i pretty much have to do that. do i run it for that time then right after that change the oil, i think so? i have not done this before (as if you couldnot tell) so can you guys help me to know what to do.
thanks,
danny

 

I always break in my new engines like this:
1: Fill engine with 10w30 conventional oil.
2: set (eyeball it) idle screw acordingly to never let the engine get below 1500.
3: After starting, immidiately take RPM to 2000 leave it there for 1-2 minutes.
4: While idling against the idle screw, check for leaks and and check timing.
5: if any leaks are found shutdown and fix quickly (do not let engine cool), set timing to around 25-30* at the 1500 "idle".
6: then for 15-20 minutes vary the rpm between 2000 and 3000 not staying at one rpm longer than 1-2 minutes. and not dropping/raising rpm agreesively.
7: let engine cool to touch, retorque heads, intake manifold, exhaust manifolds (headers) and carb.
8: Re-start car, adjust idle, adj carb, adj timing etc.
9: drive car for the first 500 miles very easy. DO not stay at one RPM for too long. Do not do full throttle accelerations and do not use the engine to brake from mid-high rpms. drive like "grandma"
10: change oil to a full synthetic, put on a quality filter.
11: Enjoy the fruits of your labor.

Now this is how I do it. I have never wiped a cam, or had any other catastrophic failure.
Others here prolly do it differently. just wanted to share my procedure.

------------------
LOBC-- SS-84

92 RS Heritage package with a 305
84 El camino

[This message has been edited by SS-84 (edited July 04, 2001).]

 

thanks ss-84

 

Red Devil posted this awhile back and I lost the link to the page. (Giving credit where credit's due...)

Strait from GM:
RECOMMENDED ENGINE START-UP PROCEDURE
1. SAFETY FIRST! If the car is on the ground, be sure the emergency brake is set, the wheels
are chocked, and the transmission cannot fall into gear.
2. Be sure to check the oil level in the engine and prime the oil system
3. Run engine between 2,000 and 2,500 RPMs, with no-load on the engine for the first 30 min.
4. Adjust the distributor timing roughly by hand for a quick start up and smoothest idle possible.
5. Adjust the carburetor settings, if necessary.
6. After the first 30 minutes of the engine running, set the ignition timing (see install ignition
section for timing specifications).
7. Drive the vehicle with varying speeds and loads on the engine for the first 30 miles. Be sure
not to use a lot of throttle or high RPM.
8. Run five or six medium-throttle accelerations to about 5,000 RPM (55 to 60 MPH), then
letting off in gear and coasting back down to 20 MPH.
9. Run a couple hard-throttle accelerations up to about 5000 RPM (55 to 60 MPH), then letting
off in gear and coasting back down to 20 MPH.
10. Change the oil and filter with 10w30SG oil and PF1218 AC Delco oil filter (PN 251605610
11. Drive the next 500 miles normally, without high RPM's (below 5,000 RPM), hard use, or
extended periods of high loading.
12. Change the oil and oil filter again.
13. Your engine is now ready for many happy cruising miles



------------------
'88 Camaro RS 2.8L
'88 Formula 350 (Too many mods to list...)

 

Ooops DP.

All that was forgotten was the medium and full throttle 'blasts' to load and seat the rings. What occurs is 'babying' the new motor wears the crosshatch pattern off the walls and sets a small ridge on the top of the cylinder. You need to beat on the motor a little to stretch the rods to wear this ridge off now before it gets too big, then when you eventually do lean on it the rings hit this and may unseat causing blowby and other probs. This is only what I heard but it seems to make sense.

 

Thanks for the correction, even though I have never had a problem. The logic is clear and I will use that next time i rebuild one.
Thanks

------------------
LOBC-- SS-84

92 RS Heritage package with a 305 3" high-flow cat and pipe with a Dynomax 3" in dual 2 1/2" out.

84 El camino- 383 CID, Performer RPM, GMPP vortec heads, Holley 750 D.P.(0-4779c), Crane Energizer 274,TCI 2500 stall, Richmond 3,42 gears, PST Poly graphite Suspension bushings, PST steering linkage, PST springs, Monte SS sway bays, Wheels from a Third gen(does that count?)

 

Mind you, all that will work (methods vary, but outcomes are similar), but you only need to run the engine for 20-30 minutes in varing RPMs for a flat tappet hydraulic (or solid). If using a roller hydraulic (or solid), then you can avoid this step. This step is used to match the two mating surfaces of the tappet and the cam in angular, tappered profile (keeps cam from wanting to walk out of the block). A roller has no need to for this, neither the procedure.

------------------
George P. Lara
1984 Z28
2001 SS Coming Soon
SCCA, SCFB, SC3GFB

[This message has been edited by MRZ28HO (edited July 05, 2001).]