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Hey there,

Recently the RB20det in my cefiro blew up,due to error on my behalf (well not really blew up but some vavles made slight contact with 1 and 5 pistons)

So i have undertaken a full rebuild on the engine which included, pulling the block apart, sourcing new R32 head which has been acid dipped, shaved slightly, new guides, new valve stem seals, "machined" vavles and pressure tested. The original block has been decked, hot tanked, (acid dipped) honed and pressure tested (as well as pistons and rods). Everything that came out of the engine e.g. crank and pistons and rods turned out to be fine.

I have sourced standard rod and mains bearings through nissan as well as new rings, oil pump, water pump, timing belt and complete gaskit set.

This weekend i am looking to re-assemble the egine starting with the bottom end with alot of help from some friends who know alot more than me about this kind of work.

My questions are, does anyone out there have the correct torque levels for rod bolts, crank, oil pump ect ect?

Also when it come time for running the engine in are there any tips or rules as to what needs to be done, i have done a bit of research in that area but usually had mixed messages about the running in period.

Also is there anything i should be doing whilst the engine is totally apart, for example adding oil restrictors to the block for head oil feed?

I was thinking of taking photos of the entire build, does anyone else think that would be a good idea, or be interested?

Thanks

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I was told to keep it off boost. Some say to give it boost but not too much.

Either way I went with what my engine builder recommended and have had no problems. No oil usage, good extremely equal compression good power and fuel economy.

Basically.. I wired open the wastegate and drove it as n/a. I gave mine lots of throttle and varied engine speed avoiding cruise and in gear deceleration at all costs. The majority of my running in was done along the seafront down south through round abouts. Basically every time I accelerated I gave it full throttle, I varied the rpm of which I changed gears at.

Initially I started the car let it idle for a few mins while I checked for leaks. I then hit the street for 10mins driving it with moderate throttle, got home and dropped the oil/filter. New oil in and then straight down the dyno for a quick afr check, then from there onwards I rev'd it to 4000-4500rpm, not all the time but the odd in gear hold through second gear.

Its how my engine builder recommended the run in. Lots of throttle, varied rpm, no gear deceleration (pop it in neutral), no extended cruising or idling.

Good luck. :blush:

Also.. Blackwood auto & dyno used to do cheap as power/afr checks for $30. This was a couple of yeares back now though.

Thanks for information, was tempted just to take it to a engine builder and have them assemble the engine for me but i would like to see how everything is done. Graham from Boss racing Differentials is helping me put it together as he used to build all of his old drag V8 engines a while back (i know a old school V8 is totally different to a RB20 lol)

Hmm i was thinking of taking the car into the hills but i would be tempted to de-accelerate in gears which i know is not really good for the run in period. Might do what you did Cubes and just take it down the espy from Moana to Aldinga a couple of times, aparently the first 50km of run in are the most important.

Also did you use a synthetic oil for run in? I always used use Motul 300V 10-40w before, but i have heard its a good idea to use mineral oil for the first 1000km's or so of run in then start using the synthetic stuff later on

As cubes mentions AFR's are very important.

I think boost is fine as long as its low boost. I ran mine in with about 5 - 6 psi. Low rpm is key as well. My limiter was

set to 5000 rpm for the run in.

It's also important to put varying load on the engine during the run in. Taking it down the freeway and sitting on 100km/h only is not a good thing.

Its worth going through a hills area that will load up the engine a bit.

Changing the oil during run is very important to. I was pretty keen with this.

Engine was first filled with run in oil but most people say any mineral oil is fine.

First fire up ran it till it got hot at about 2000 rpm.

Shut down change the oil. This gets most the assembly lube outa the engine.

then did 100km/s oil change

then another 400ks then change oil and went to synthetic

then 500k's and another synthetic change

total 1000k's and then time to tune it for full rev range.

Take heaps of pics of build too. People always interested :blush:

Cool, thanks for the help.

one more question i have is should i go for a oil pump collar for my new oil pump or just let it drive off the usual spot on the crank? Its not really a highly tuned engine, only had around the 200rwkw mark before witha Rx7 hybrid turbo on in, was running quite rich too, i will be turning my boost controller off for the run in which means it will be running 5psi of fury haha.

Ill be sure to take photos of the build

http://i3.photobucket.com/albums/y65/Ceffy_SA/DSC00759.jpg

http://i3.photobucket.com/albums/y65/Ceffy_SA/DSC00777.jpg

http://i3.photobucket.com/albums/y65/Ceffy_SA/DSC00781.jpg

Flintstones power^^

Load up where u can, let it warm up to about 45 degrees before moving, keep it under 4500rpm and as your k's increase you increase th rpm/boost as well you dont want rich afr's theyll just wash the bore down, and Comments above aswell And Varying rpm, no really long straight runs at constant rpm, If your at the lights for a couple of minutes vary the rpm give it a stab to 2000rpm every so often.

Oh and oil changes

100, 500, 1000, 2000, 5000, and then your regular intervils

Plenty of ways to do it

Worth getting new rod bolts and head bolts? Have been thinking about it, might as well do it properly the first time around

Edit: Just rang Nissan, Rod bolts are only $6.85 each, rod nuts are $1.50 each and head bolts are $4.30 each so all up it comes to $160.4 for new rod bolts/nuts and head bolts so i think ill be getting new ones. Just out of interest how can they charge over $2400 for a new set of hydraulic lifters (24), sheesh!

Edited by Ceffy_SA

get some ARP rod bolts and so on... spend the extra for quality.

as for run in.. im a firm believer of running it in like you would normally drive it. Read this article for more info. RUNNING IN

Ive had rotors, and several other piston motors built up. and have always run them in hard, While not absolutly thrashing them by sitting on the limiter etc. But rev them out and load them up!

light load and low revs will result in a motor that is un responsive!

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