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MG MGB Technical - Driven Racing Oil?
|I am using Driven Racing Oil (Joe Gibbs) BR Conventional 15w-50 Break-In oil in my rebuilt competition engine on the recommendation of my engine machinist and local speed shop with K&N filter. Just changed oil and filter after 20 min run in at 2000 rpm followed by 20 km drive in stop start traffic limited to 4000 rpm. Cam and followers coated with Suzuki moly paste (Peter Burgess recommendation). Bearings and journals protected with Clevite Bearing Guard during assembly. Pre filled oil cooler and filter, charged oil pump from block outlet to the oil cooler. Got60 psi oil pressure with starter motor prime with plugs out - 65 psi at idle with 85-90 C water temp.|
My precautions to prevent premature cam lobe and follower wear on high lift cam, high ratio roller rocker! Any comments from other users?
|That is what my machine shop recommended for my rebuild, but they said it was ok to run for 100 miles prior to changing.|
|Tend to agree with Bruce here|
the whole idea of break in oil is to get the rings 'seated' into the bore and changing it out too early can slow the bedding in process - especially if you are replacing it with a race oil
With our Chevs which didn't need cam runin so much being rollers, we would start them up and run for 5-10 mins then drop the oil and filter and refill with running in oil again and go and do 100 or so laps at no more than 3/4 throttle but lots of load variance
Then change to propper oil and go for it
I have refill with the same Driven Break-in oil and will now run for around 300 kms will plenty of variation and 4000 rpm limit. I assume this oil is high detergent also and will remove all the moly paste residue etc. as well as allowing rings to bed in.
Yes the whole idea of break in oil is to give your engine the chance to do exactly that--break in
With a normal road car with normal oil it isn't so much a problem--but with a new engine, if you are going to run it on proper race oil with all it's slippery additives right from the start, it simply doesn't get the friction thing happening enough to bed in properly and will probably take ages to get the rings bedded in-if ever
This is also a reason for not running outright race oil in a normal road car as eventually they glaze the bores up
There are plenty of good oils around now without resorting to race oils for road use
I'd imagine breakin oil is fairly high detergent oil but that molly paste, it's unbelievable how that hangs in there- If you pulled your engine apart again today you would still see signs of it in there-But having said that, really it's only there to give your poor old dry engine the lubed up start to life it deserves-
That Suzuki paste, Is that graphite colour, or is it the creamy coloured one--?--just interested
|Just a comment as regards "running in". The 20 minutes at 2000rpm is exactly spot on. But the stop start traffic driving, possibly isn't if you were making the engine ".work"! Revs are not that detrimental but pulling from low revs is.|
|It's very dark grey Willy.|
|Peter Burgess Tuning|
thanks for that
I have a largish tube marked Suzuki with no part no. and it's a clearish creamy colour--slippery as hell, don't know what it is, I was just hoping it might have been it---
Possibly CV joint lube then-or something else-I think I'll bin it, although it seems a waste of 300ml of slippery stuff
|Peter Burgess Tuning|
This thread was discussed between 13/03/2017 and 15/03/2017
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