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Rb20det Rebuild


sky_2.0T
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Hey mates, my car has just been totalled. some girl pulled out in front of me and my car went crunch. Motor is fine, radiator was like a cushion, only really hit p/s pump. motor cradle is a little bent on left.

anyway I was wondering whats involved in a typical rebuild. All new gaskets, piston rings, hone? Motor has close to 130k I'm sure.

Looking to stick with stock turbo, up the boost to 12, cooler, intake, etc.

thanks fellas :)

Edited by sky_2.0T
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Hot tank block

Hone

Deck

Linished/balance Crank

Pistons & rings

Bearings

Head bolts/studs

Balance/crack test rods

Rod bearings

Head gasket

Rear main & main seal

Water pump

Machine head

Timing belt

Maybe new rod bolts

Oil pump depending on how yours is, but you would probably want one as its a new motor.

Then assembly and you would probably want the whole thing balanced as well.

Full gasket kit would be the easiet way.

Add all that up and you got your self a rebuild, but there is probably a few things I have missed..

Probably best/cheaper to just buy a 2nd hand RB25 motor, unless you really really really want to keep the RB20.

Thanks,

Abu

Edited by abu
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from what I've read, there is noting wrong with your motor except radiator and power steering pump?

so are you buying a rolling shell to put your stock motor in to?

Why not buy a new R32 gtst and strip your old smashed one for parts like motor, interior etc..

People are always looking for R32 bits as they're all falling apart.

sell off everything from the old car and just use that money to modify the new car with 12psi, cooler and intake.

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You could buy my RB20 with 20thou oversize forgies travelled under 10,000km comes with recoed head with 2 dropped exhaust valves in cyl 3 and a spare head ready to bolt together for $1,800.

post-24062-1187670022_thumb.jpg

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You could buy my RB20 with 20thou oversize forgies travelled under 10,000km comes with recoed head with 2 dropped exhaust valves in cyl 3 and a spare head ready to bolt together for $1,800.

post-24062-1187670022_thumb.jpg

nice engine bay mate :(

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Looks tough as!

Thanks,

Abu

Thanks for the input, especially abu. I think I'll compression test it, and if numbers look good just keep it the way it is. Exhaust was just smelly! Too rich on low rpms, should these motors need a tune with JUST intake and exhaust? I'll post up a dyno sheet soon... thanks all :)

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any turbo nissan motor will benifit from a tune even if it just has intake and exhaust...they run so damn rich from factory.

we tuned my friends car for 550cc injectors and 14psi on the stock turbo, goes like hell compared to a std 20 at 14...in the end removed a ton of fuel.

Edited by carl h
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any turbo nissan motor will benifit from a tune even if it just has intake and exhaust...they run so damn rich from factory.

we tuned my friends car for 550cc injectors and 14psi on the stock turbo, goes like hell compared to a std 20 at 14...in the end removed a ton of fuel.

would it benefit the motor to run rich at any level of rpm?

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would it benefit the motor to run rich at any level of rpm?

Its best to get it tuned so it only uses what it needs. When you say rich, it usually means its using in excess of fuel that it should be, therefore its a waste.

That being said, rich is better than lean any day! You would rather it be running rich with a little extra fuel, then running lean and do some damage.

The best posssible thing you could do is get it tuned, that will give you the most gains/improvement in performance and also fuel economy.

Bit of extra information in regards to tuning, for your own use:

For R32 ECU you can get a REMAP, which they re-tune the standard ECU, or just got a full stand-alone ECU (Apexi PFC, WOLF, Microtech, Autronia etc..).

Most use a REMAP, and some use a SAFC II, there both fairly cost effective.

Personally, I will be using an SAFC II, which is a piggy back fuel only computer. That will serve my purpose, and has the compacity to run 2x fuel maps.

Thanks,

Abu

Edited by abu
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Its best to get it tuned so it only uses what it needs. When you say rich, it usually means its using in excess of fuel that it should be, therefore its a waste.

That being said, rich is better than lean any day! You would rather it be running rich with a little extra fuel, then running lean and do some damage.

The best posssible thing you could do is get it tuned, that will give you the most gains/improvement in performance and also fuel economy.

Bit of extra information in regards to tuning, for your own use:

For R32 ECU you can get a REMAP, which they re-tune the standard ECU, or just got a full stand-alone ECU (Apexi PFC, WOLF, Microtech, Autronia etc..).

Most use a REMAP, and some use a SAFC II, there both fairly cost effective.

Personally, I will be using an SAFC II, which is a piggy back fuel only computer. That will serve my purpose, and has the compacity to run 2x fuel maps.

Thanks,

Abu

so with SAFC-II you could have a low boost and high boost setting eh?

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so with SAFC-II you could have a low boost and high boost setting eh?

Yep, sure can.

Doesn't controll boost obviously, just the fuel side of things. :action-smiley-069:

But yes, 2x fuel map, high boost & low boost.

Thanks,

Abu

Edited by abu
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safc II is not a boost controller.

it can't set boost.

it is a piggy back air:Fuel adjuster.

it basically "modifies" the signal the AFM sends to the ECU to adjust the amount of Fuel the ecu puts in to the mixture.

the ability to have 2 maps to me seems like a waste of time..

why would you want 2?

a good one and a bad one?

a good one and a better one?

why wouldn't you just have the best tune you can and leave it?

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safc II is not a boost controller.

it can't set boost.

it is a piggy back air:Fuel adjuster.

it basically "modifies" the signal the AFM sends to the ECU to adjust the amount of Fuel the ecu puts in to the mixture.

the ability to have 2 maps to me seems like a waste of time..

why would you want 2?

a good one and a bad one?

a good one and a better one?

why wouldn't you just have the best tune you can and leave it?

A waste of time?

Maybe you want to have a high boost, 18psi fuel map, and a low boost, 10psi fuel map, or even a high boost 18psi fuel map, and a stock boost economy fuel map for long trips?

You would want your 18psi tune to be reasonably rich so that it is safe, but if your just daily driving it to work and back, you would probably want it to be slightly more economical, so you'd put the boost down, and drive it normal. So it would make sense to have a more lean map, for better fuel economy..

Makes sense to me, and is definately useful in the above context.

Its not like its hard to change between two maps, its just a click of a few buttons.

I think what he was asking is, can you have a high boost fuel map and a low boost fuel map, he just didnt word it in such a way.

Edited by abu
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hmmm..

someone clarify this then.

Are the SAFC settings static?

I mean, if you tune a car with 18psi boost.

it will have say 300CFM of air at 5000rpm and the ECU will add X amount of fuel to it. you can tune the amount of AIR flow the ecu sees via the safc so the ecu adjust the amount of fuel it dumps at that particular RPM.

if you then lower the boost to 10psi, give it a hit, at 5000rpm, it will be sucking in say 200CFM of air.

the setting you made at 5000rpm before via the SAFC (lets say you made it so it removed fuel by 3 points to get the A:F ratio at 5000rpm to 12.0:1), does it still remove the 3 points of fuel?

All this may be confusing...

18psi boost @ 5000rpm = 300CFM of air

10psi boost @ 5000rpm = 200CFM of air

you make a setting on the SAFC at 5000rpm point to make the ECU remove 3 points of fuel when tuning the 18psi run.

what happens at 5000rpm when you run 10 psi?

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hmmm..

someone clarify this then.

Are the SAFC settings static?

I mean, if you tune a car with 18psi boost.

it will have say 300CFM of air at 5000rpm and the ECU will add X amount of fuel to it. you can tune the amount of AIR flow the ecu sees via the safc so the ecu adjust the amount of fuel it dumps at that particular RPM.

if you then lower the boost to 10psi, give it a hit, at 5000rpm, it will be sucking in say 200CFM of air.

the setting you made at 5000rpm before via the SAFC (lets say you made it so it removed fuel by 3 points to get the A:F ratio at 5000rpm to 12.0:1), does it still remove the 3 points of fuel?

All this may be confusing...

18psi boost @ 5000rpm = 300CFM of air

10psi boost @ 5000rpm = 200CFM of air

you make a setting on the SAFC at 5000rpm point to make the ECU remove 3 points of fuel when tuning the 18psi run.

what happens at 5000rpm when you run 10 psi?

Hmm.. little bit confusing and a bit over my head I think. :action-smiley-069:

I will let someone else comment.

Basically its 2 seperate fuel maps though, so fuel map 1 may have extra fuel added through out the REV range, where as fuel map 2 maybe remove fuel through out the REV range.

Dont know if that is relavent, but thats basically how it works.

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