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Im about 50% through my rb30/25de build and was wondering what people do when running in engines.

Ive read numerous stories suggesting 1000kms is enough before winding lots of boost into it, however others suggest 5000kms.

In the first 1000 kms how far do you rev it, when do you dyno/redyno etc.

All the information ive got so far is so varied.

Engine is standard rb30 with rebuild head with aftermarket valve springs, acl pistons and bearings. Im thinking of running it in with a 25t turbo before i go to something t66 size

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I'm still trying to get my rebuilt RB25DET to run in properly (not sure if it has or not). My initial attempt was simply putting miles on the engine, and a lot of those were highway. And I "nursed" the engine, driving like grandma. Wasn't very successful.

I was advised to use a good quality mineral oil (I'm using BP Visco 2000), and you need to load the engine. So every opportunity I get, if I'm driving up a hill, let the car slow to around 50 kph (around town - on highway slow to 80 - 90), then floor it. This will load the engine - you can let it produce some boost, because this is load on the engine, and will force the rings out against the bore.

Unfortunately, this all goes against my nature - I now need to "hoon" around the place so I load the engine at every opportunity.

so when you go up a hill.. you'd do it in which gear to make the load ???

im in the process of running in my engine now... i think im doing it right...it seems happy and fine...

i still dont understand though.. how do u get load without rpm / boost.

Like if i floor it isnt it gonna go on full boost.. which would be bad ya ???

I was advised to use a good quality mineral oil (I'm using BP Visco 2000), and you need to load the engine. So every opportunity I get, if I'm driving up a hill, let the car slow to around 50 kph (around town - on highway slow to 80 - 90), then floor it. This will load the engine - you can let it produce some boost, because this is load on the engine, and will force the rings out against the bore.
is there anyway to look without a compression test / catch can.. ? or anything usual that would happen that i could see ??

Im just curious about mine.. im sure i'll run it in fine... i just get paranoid is all :)

It will use oil

The plugs will be oily

The exhaust will be black

There will be oil in the inlet pipes

There will be visible blow by coming out of the breathers on the cam covers (if you remove the pipes)

It will have lots of leakdown on a leak down test

The oil will go black very, very quickly

It will make less power than it should

It will be harder to start when hot than it should be

It will blow blue smoke out of the exhaust under power

It will blow blue smoke out of the exhaust on over run

When you take the plugs out you can see the tops of the pistons and they will be black and oily looking

Enough?

:P cheers :)

Here's a somewhat controversial way to break in an engine. It makes sense to me, and I will be doing it if/when I do a rebuild unless someone else tells me they tried it and killed their engine! Or if someone can put up a similar well-put argument as to why it would be bad. Hopefully someone has already tried it and can tell us what happened, otherwise I may be the guinea pig in due time.

Here's a somewhat controversial way to break in an engine. It makes sense to me, and I will be doing it if/when I do a rebuild unless someone else tells me they tried it and killed their engine! Or if someone can put up a similar well-put argument as to why it would be bad. Hopefully someone has already tried it and can tell us what happened, otherwise I may be the guinea pig in due time.

Old news, that article has been around for years, I have previously written and posted a critique. The main problem is it assumes that your engine is PERFECTLY tuned, ie; your NEW engine is exactly the same spec as your OLD engine. This doesn鈥檛 seem to be the case on SAU, the guys here build a new better/bigger/stronger engine with large variations in the components, both internal and external.

So it鈥檚 classic Catch 22, the engine needs to be run in vigorously, but you can鈥檛 because it hasn鈥檛 been tuned PERFECTLY. You can鈥檛 tune it PERFECTLY because it hasn鈥檛 been run in.

As a result, I stick by my previous running in process, which is hardly gentle.

:P cheers :)

Old news, that article has been around for years, I have previously written and posted a critique. The main problem is it assumes that your engine is PERFECTLY tuned, ie; your NEW engine is exactly the same spec as your OLD engine. This doesn鈥檛 seem to be the case on SAU, the guys here build a new better/bigger/stronger engine with large variations in the components, both internal and external.

So it鈥檚 classic Catch 22, the engine needs to be run in vigorously, but you can鈥檛 because it hasn鈥檛 been tuned PERFECTLY. You can鈥檛 tune it PERFECTLY because it hasn鈥檛 been run in.

As a result, I stick by my previous running in process, which is hardly gentle.

:P cheers :)

just so i dont need to pm you hah, what could i search on to find your article

i ran it for 10 mins with some cheap oil, then dropped that out and put some quality mineral oil in and drove it round for the next 500k's giving it a bit of load (about 75%) up to around 4000rpm max. Once it got to 500 k's i did another oil change with the same oil again until 1000k's where i went and got it dyno tuned and had the wastegate actuator re-connected (used no boost for first 1000kms). Have now done around 1500kms with 10 psi. Will do next oil change at 5000kms! From a thousand k's i started to give the car a bit of stick revving it to about 6500rpm and she feels great!

It will use oil - USES A LITTLE

The plugs will be oily - WILL CHECK SOON

The exhaust will be black - ITS BLACK ORIGHT

There will be oil in the inlet pipes - HAS A LITTLE OIL IN THE INLET PIPES

There will be visible blow by coming out of the breathers on the cam covers (if you remove the pipes) - YEP

It will have lots of leakdown on a leak down test - MIGHT HAVE TO GET CHECKED I THINK

The oil will go black very, very quickly - GOES BLACK FAIRLY QUICKLY

It will make less power than it should - THIS SEEMS TO BE A DEFINITE

It will be harder to start when hot than it should be - IS A LITTLE HARDER TO START BUT COULD BE MY POWER FC SETTINGS!

It will blow blue smoke out of the exhaust under power - HAVEN'T NOTICED THIS ONE YET

It will blow blue smoke out of the exhaust on over run - AS ABVOE

When you take the plugs out you can see the tops of the pistons and they will be black and oily looking - WILL HAVE TO CHECK THIS TOO!

OHOH, i'm a bit worried i didn't bed the rings in properly now, it sure would explain a few things but i was sure i did everything right when driving the first 100kms, i gave it a bit of load and had no boost! Fingers crossed i'm just being paranoid!

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