[Sideways Steve]

Me again !!

Quick one, without pulling stuff apart is there any way at all of telling if an RB26 has had work ? Apparently this one has been rebuilt with fully forged internals etc but obviously theres no real way I can think of to tell ??

Just wondered if theres any particular areas to look at that may give away that its had a rebuild ?

I.E, on the rx7's you can usually tell due to the colour of the sealant that will be showing between each of the rotor housings.

On the S13 CA18DET you can easily see if its running a stock or metal HG therefore implying its been apart.

 

[Tiger_kpt]

Hi Steve. Only real way (without taking the engine out and apart) is to use an endoscope. You may be able to get away with removing a spark plug and using a small flashlight shone through the hole to look at the piston crowns. But that would only confirm that it is running forged pistons. Endoscope is the only real way to see the conrods - and crank to some degree. You can't just whip the sump off of these engines whilst in situe on a vehicle. To take the sump off you have to remove the whole engine. History goes a long way with these cars - especially if it is a well known one within the community.
That's if it is meant to be a standard displacement forged engine. However...

if it is meant to be a larger displacement forged engine (such as 2.8, 3.0, etc) you could also measure the stroke by removing a spark plug and using measuring apparatus. 95% of the time, any RB engine that has a larger displacement and stroke over a standard 2.6 RB engine - has to be forged.


Many of the tuners have endoscopes - such as TR Racing, RK, etc, etc.

Hope that helps. :thumbsup:

 

[Sideways Steve]

Lovely, and I completely forgot about the endoscope method ! I have one LOL Im a Mech Eng/Instrument Tech to trade so have loads of fancy bits of kit, and when I dont have it i usually have access to it via work

I know you cant just whip off the sump, must be a nissan thing as the 200's are the same. Its a right PITA !!

Im not familiar however with the visible difference between a stock RB piston and a forged one, any pictures of the crown or specific marks to look for to identify it ??

The problem with this car is that its never really been on the scene, it was brought over privately 4-5 years ago by an older gentleman after being built in Japan by Pheonix's Power (Formerly Garage Fukui) specifically for him. (or so im lead to believe)

He only used it very rarely and it was stored in a garage most of its life until early this year when it was bought by the guy who currently has it.

Its only done just over 5000 miles in the last 4 years but one of the things detailed on the list of stuff was a full rebuild, stock displacement but forged up.

He never posted on any forums etc as far as im aware and neither has its current owner.

The current guy is in the army so again hasnt used it much and was only used through the summer.

 

[RB26 240Z]

Get it on a dyno for a power run.

 

[mifn21]

Power run isn't gonna tell him much unless its putting out serious power

 

[dave1983]

I'd be a bit concerned if its only done 5000 miles in last 4 years, how often has it been started or has it just been left for ages in between drives, has it been stored in a garage or sat on his drive in all weathers? How often has it had fluids changed, including petrol as im sure if the bloke is in the army and hes been on duty for over six months or more then it will not of had much care. i.e just started driving it on petrol thats been in sat in the tank for 6 months+ although engine is obviously very important i would look at the car as a whole as well.

poss ask him to drop it down to a tuner so they can take a good look at it for you:thumbsup:

 

[Sideways Steve]

As said a dyno run wont tell me if the engine is forged.

Dave, its been started up and run each weekend, stored in a heated garage and had fluids all looked after too despite not being driven much. Youcan tell its certainly been well looked after thats for sure, ive had enough cars and experience to be able to spot a dog So im not too worried about that side of things.

Really my concern is more that of ensuring it has the bits im told it does, not whether or not its running xxx BHP

Hope that makes sense ?

Cheers for the replies so far folks you seem a friendly bunch !

Being totally honest too im getting it for a steal as hes needng it gone and cash in his hand for various reasons. So im willing to take the gamble on it assuming it seems all Aok when I go see it properly tomorrow morning

If its in as good nick as he says and its not running rough/smoking/knocking etc then I think I will finally be an R32 GTR owner

 

[Jez200]

The forged JE pistons in my old CA18 always used to 'slap' when the engine was stone cold. Upto temp they quietened down as they expand.. Thats one way of telling!!lol

 

[Marko R1]

The forged JE pistons in my old CA18 always used to 'slap' when the engine was stone cold. Upto temp they quietened down as they expand.. Thats one way of telling!!lol

good point - both of my engines had piston slap when cold, unusual sound then after 30sec or so it disappears

 

[icydude]

The forged JE pistons in my old CA18 always used to 'slap' when the engine was stone cold. Upto temp they quietened down as they expand.. Thats one way of telling!!lol

I found ca's with forged pistons make way more racket then rb's.
Thinking about it now my cosworth pistons don't slap at all in my rb26

 

[Marko R1]

its not really a piston slap noise but it is a distinctive alloy type sound - almost like knocking a piston with a rubber hammer if u can imagine

 

[Sideways Steve]

Yeh I know what you mean and mine does sometimes do that when very cold.

Jurys still out though so until the day when I need to open her up I shall just play it safe and assume its just a freshly built stock engine (apart from the stuff I know like HG etc)

If I look at it with that view Im less likely to kill it LOL

 

[[email protected]]

Sorry for the thread highjack , i have sorted a endoscope camera (seesenake from rigid) and i dont know the visual diferences from the stock pistons to the uprated :chairshot ones could someone tell me what i should look for ? like: engravings,aspect, etc...
If you guys have some fotos that would help :clap:

Thanks guys

 

[davew]

Sorry for the thread highjack , i have sorted a endoscope camera (seesenake from rigid) and i dont know the visual diferences from the stock pistons to the uprated :chairshot ones could someone tell me what i should look for ? like: engravings,aspect, etc...
If you guys have some fotos that would help :clap:

Thanks guys

Stock piston will have O5U on the top, forged usually nothing as they put the company logo under the crown:thumbsup:

 

[[email protected]]

Stock piston will have O5U on the top, forged usually nothing as they put the company logo under the crown:thumbsup:

Just got back from my garage,and they re stock like you said davew they have 05U engraved.:thumbsup:
I have one more question tho: is it normal the last 2 pistons have more carbon deposits than the other ones?
I couldnt see very well because the camera diameter is larger than the plugs and i didnt had a spanner to bring them up but it looked like they had a bit more of carbon deposits.
Not all is bad news from what i have saw there were no signs of detonation :clap:
Thanks guys:thumbsup:

 

[davew]

Just got back from my garage,and they re stock like you said davew they have 05U engraved.:thumbsup:
I have one more question tho: is it normal the last 2 pistons have more carbon deposits than the other ones?
I couldnt see very well because the camera diameter is larger than the plugs and i didnt had a spanner to bring them up but it looked like they had a bit more of carbon deposits.
Not all is bad news from what i have saw there were no signs of detonation :clap:
Thanks guys:thumbsup:

Sounds like the fueling map is squirting more to the back pistons to keep them cool:thumbsup::thumbsup: Not a bad thing

 

[[email protected]]

Sounds like the fueling map is squirting more to the back pistons to keep them cool:thumbsup::thumbsup: Not a bad thing

Thanks mate for all the help:thumbsup: