8POTS

Hi Guys,
another oily question. I have just had a 427 CID LS1 built and installed in my '01 VX series 1 SS Commodore. It was broken in on an engine dyno and driven for 600-700 KMs after that. It has also done time a chassis dyno. The oil used was a non-friction modified Motul Titan 15W40.

Now, the oil was changed after I did 1000km (600 miles) and was quite black due to the amount of hard work it had done and periods of rich fueling contaminating the oil during tuning. That's fine and was expected.

The service was done...new filter and new oil. The oil used was a Penzoil synthetic 5W50. The Tuner (who is a master engine builder also)said that Synthetic is fine to start using as the engine was broken in well and truy on the engine dyno...to quote "if the rings aren't bedded in the first 50km 30 miles), they never will be"...cool.

The workshop that did the change said that the Penzoil used was non friction modified synthetic...is there such a thing? I read in site after site that friction modified or Synthetic oils should be avoided for 3,000 miles or longer and I guess I worry I may be setting myself up for bore glazing....especially if I do 50/50 highway/city driving. I do try to mix the revs up though ...and give some higher revs too.....here and there.

I have done about 70 miles on the synthetic. If I choose, is it ok to return to a mineral / blended oil or am I stuck using a synthetic and if so , is it ok to continue given that the engine is already broken in on the engine dyno?

Nasty N8

iTrader: (33)

I don`t think you need to. Looks like you have plenty of time on the reg. oil the synthetic will be just fine from here on out.

I have never heard of non friction modified synthetic?

Nate

santino04

Yeah I agree you should be good to go. As far as oils they are all about the same, conventional is conventional and synthetic is synthetic. Im sure there are some minor differences and manufacturing methods, but you know???? As they say its all a name game, and how who can make it look and sound better. I actually have this freind that is a chemical engineer works for some big *** company out west, I was telling him about royal purple how I put it in my car....hes like all that **** is the same...I was like no way...hes like yeah. So I dont know but I like to think its awesome so I run royal purple or mobil synthetic. As long as its synthetic always!! Good Luck

Patman

There are lots of non friction modified synthetics, these are the diesel synthetics such as Rotella 5w40, Delvac 1 5w40 and many of the 15w40 diesel synthetics (such as Redline or Amsoil's diesel synthetics)

VSGLS1

iTrader: (8)

Whats the pros/cons of running synthetics too early in a newly built engine? Say after 500 miles and 2 dino oil changes later?

WulfgarSS

The rings on a new/fresh motor need to set. Thus, use dino oil up to 9k miles. After 9k /3rd oil change go full synthetic. That's the gospel.

WG

Patman

Many new engines come from the factory with synthetics, so it's a myth to think the rings won't seat. They definitely will.

But if you get your motor rebuilt, you'll want to stick with a cheap oil simply because you'll want to change the oil often to get rid of assembly lube, etc. Rebuilds are typically more "messy" than factory fresh motors, so you need to do a lot of frequent changes at first on a rebuild.

8POTS

Thanks for that Patman, hoped you might post here...I guess I was concerned that the .003 thou p/b clearance used for my forged setup might have some bearing on things. I do trust the tuner though , so I will keep a synthetic in there. (just have to make sure I give her a 'squirt' now and again when on the highway ). Like I said , she was run in well and truly on an engine dyno for some hours and had good high rev power runs on both the engine dyno and the chassis dyno so I know she has nicely bedded rings.

I think 5w50 might be a bit thin at cold given my climate here in Sydney...might change to a 10W40 or a 15W40 on the next drop (maybe a 10W with winter coming).

I don't mind changing synthetics at 5,000 km intervals even though it seems wasteful. Just how often should I drop the oil to get the last of the rubbish out of the motor?

BIGBOS

I was using valvoline 10w40, non synthetic for break in, got an oil change, have been using royal purple recently, going to change to redline 10w40 before it hits the dyno

Buckmaster

I use 20/50 in the hotter weather (regular oil) and 10/30 in COLD months in my 436ci..................