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I recently had a 422 built by one of our forum sponsors. After getting the motor installed and up and running, we’ve been following a strict break-in regiment that has consists of or will of:
1. Using a non-synthetic oil for the first 4,000 miles
2. Changing the oil at 500 miles and 1,000 miles
3. No WOT / Dyno pulls until roughly 1,000 miles has been reached.
Currently my new motor has about 1,100 miles on the clock… with what we feel is excusive oil consumption. Right now the car is burning about 1 quart every 130(ish) miles. The builder notified us, that this appears to be high although maybe more time is needed in order for the rings to seat? Currently I’m logging all oil consumption, in the event the builder needs proof this is in fact happening. The builder has also suggested we make sure the car isn’t was washing the cylinders down with fuel, creating ring seating issues. We’ve checked this, and this isn’t the case. Another suggestion was to check my PCV system, which at this point there’s noticeable crank case pressure occurring. At this point, we’ll continue to monitor the situation however she doesn’t appear to be letting up. Has anyone else experienced similar behaviors on their aftermarket motor? I’m asking because we really don’t have a baseline, as to what we should expect.
That oil consumption is excessive IMO. I had my 383 built locally, changed the oil at 500, 1000, and 2000 and miles. Used 5W30 dino oil for first 1K miles, 20W50 on the last change (still dino) and will switch to synthetic after 5K miles. I have never yet had to add oil, including a 1K round trip weekend to Florida, and last weekend a trip to lil'Talledega when I ran HARD at WOT.
Are you varying the RPM's a lot (recommended)?? Get on it medium hard beween 1K and 5K RPM's and see if you can get them to seat. Don't switch to synthetic until/unless you get this fixed, otherwise it will always be an oil burner.
We've varried the RPM's quite a bit.. usally keeping them around 2k-5k. It wasn't until I had 1k on the clock that we even went 60% trottle on the car. At 1 quart per every 130ish miles, that's not a street-able car.
That's way too much! I had mine re-built by Mike Norris and have put almost 5,000 miles on the motor as of now and I have no oil consumption whatsoever. It never used any even when it was "breaking in". I had it re-built because of oil consumption and smoking @ WOT. It was using 1 qt every 1,000 miles or less (miles) depending on driving habits. Do you know what kind of rings were used?
sound like trouble to me. I would check everything over before making a stink with the vendor (pvc, leaks, contamination in water or a fuel wash)
next do a leak down check of the cylinders this will tell you the condition of ring seat. if you have a high percentage of leakage and its not valve related bring it back.
my experience with molly coated rings is 500 mi. their ready to go.