Jump to content
SAU Community

Boosted Rb Converted To N/a

Rallye

By Rallye,
in Engines & Forced Induction

 Share

Recommended Posts

Rallye Enthusiast

Rallye

Posted
Posted (edited)

Just recently my friend has told me he can do RB conversions to N/A (non-turbo) in his own backyard. I personally thought it was not possible to N/A a turbo RB but my friend insists it can be done.

I was quite interested so I asked him how it could be done and is it street legal/P Plate legal.

Heres what his said:

He said there are different ways of doing, he told me I'll have to block off the turbo lines (oil feed, water feed, and the returns), the air flow meter has to be relocated to a pipe that eventually runs off the throttle body, the exhaust, get a N/A manifold but he wasnt sure if it works with the factory exhaust.

Turbo manifold, remove the turbo itself, and get a pipe made up to match the turbo manifold to the front pipe or he said I can modify the turbo itself and block the front of it.

This is what he told me about it being legal:

He know quite a few people running around in backyard N/A conversions with no trouble at all. He also said its 100% P Plate legal, as long as I can prove its non-turbo. I should just go to EPA or mechanic and get a certificate that its non-turbo.

What do you guys think? So it can actually be done?

Cheers.

Edited by Rallye
Link to comment
https://www.sau.com.au/forums/topic/332441-boosted-rb-converted-to-na/
Share on other sites
89CAL Grand Master

89CAL

Posted
Posted

Do the smart thing that not many people do

Buy a non turbo Skyline, Drive it, save your money and either buy a GTR/GTST when your done with P's Or spend the money on building a decent engine in the mean time

From the sounds of it your mate doing a 'backyard job' is dodgy at the very least

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)
Just recently my friend has told me he can do RB conversions to N/A (non-turbo) in his own backyard. I personally thought it was not possible to N/A a turbo RB but my friend insists it can be done.

I was quite interested so I asked him how it could be done and is it street legal/P Plate legal.

Heres what his said:

He said there are different ways of doing, he told me I'll have to block off the turbo lines (oil feed, water feed, and the returns), the air flow meter has to be relocated to a pipe that eventually runs off the throttle body, the exhaust, get a N/A manifold but he wasnt sure if it works with the factory exhaust.

Turbo manifold, remove the turbo itself, and get a pipe made up to match the turbo manifold to the front pipe or he said I can modify the turbo itself and block the front of it.

This is what he told me about it being legal:

He know quite a few people running around in backyard N/A conversions with no trouble at all. He also said its 100% P Plate legal, as long as I can prove its non-turbo. I should just go to EPA or mechanic and get a certificate that its non-turbo.

What do you guys think? So it can actually be done?

Cheers.

Of course it is possible to convert a RB25DET to a non turbo RB25DET (notice how I didn't write RB25DE for one simple reason that I will make shortly) no one has ever argued that point. Every one argues the point it is a hell of a lot of work (more so in parts than what you have simply listed), ends up costing quite a bit of money and at the end of the day it will drive like shit and have shithouse fuel economy compared to a factory RB25DE due to the compression ratio! This is the key factor here.

Also as to legalities every state would be different. At the end of the day the car is registered and complianced as a turbo Skyline, when you say taking it to a mechanic to get a certificate, im assuming what you ment to say is to take it to an Engineer for a Engineers certificate and mod plate which in some states may make it legal.

Once again, what the hell is the point?

Edited by PM-R33
Rallye Enthusiast

Rallye

Posted
  • Author
Posted (edited)
Can it be done: Yes

Is it worth it: No not really

Buy a non-turbo Skyline

Just as I thought, can be done but not really worth it.

Lots of work there. It will cost more to buy a turbo skyline, in general, than a non turbo one. Then you'll spend extra to modify it to be non turbo. Unless you were given a turbo skyline for free/VERY low price, this is not economically feasible.

Yeah but I want a R32 N/A which in RB25 is quite a rare find. What do you think if I buy a RB25DE and drop it in a R32 GTST? Same story? Or more practical?

Do the smart thing that not many people do

Buy a non turbo Skyline, Drive it, save your money and either buy a GTR/GTST when your done with P's Or spend the money on building a decent engine in the mean time

From the sounds of it your mate doing a 'backyard job' is dodgy at the very least

Well he is good with engines etc, but if something does go wrong then Im in trouble.

9:1 compression in a turbo engine. 10:1 compression in a non-turbo engine.

If you've ever driven a hyundai getz, that's what you can expect from a deturbofied 25det.

Haha are you serious? Man thats a big turn off lol. Thanks alot.

Of course it is possible to convert a RB25DET to a non turbo RB25DET (notice how I didn't write RB25DE for one simple reason that I will make shortly) no one has ever argued that point. Every one argues the point it is a hell of a lot of work (more so in parts than what you have simply listed), ends up costing quite a bit of money and at the end of the day it will drive like shit and have shithouse fuel economy compared to a factory RB25DE due to the compression ratio! This is the key factor here.

Also as to legalities every state would be different. At the end of the day the car is registered and complianced as a turbo Skyline, when you say taking it to a mechanic to get a certificate, im assuming what you ment to say is to take it to an Engineer for a Engineers certificate and mod plate which in some states may make it legal.

Once again, what the hell is the point?

Ah right, Ill ask him about the compression rate and see what he has to say for it. Im guessing this is when unreliability kicks in aye? Like I said above, what do think if I bought a RB25DE block and drop it in? Still not worth it?

Legality is more important to me than anything else. I dont want to be driving on the edge of my seat everywhere I go. Ive heard that even if you do deturbo an engine/car its still classed as a turbo. Either if its true or not Ill have to heavily research to get a answer.

Thanks alot guys, any more comments would be helpful. :)

Edited by Rallye
CeJay Grand Master

CeJay

Posted
Posted

This has been posted over and over. Don't bother, from what I've heard if you de turbo a turbo car it's still classified as a turbo. Buy a cheap car and then get a turbo skyline when you finish your p's, or buy a non turbo skyline and upgrade to a turbo down the track.

PM-R33 Grand Master

PM-R33

Posted
Posted

If you take off a turbo from a GTST it is 100% still classed as a turbo car if you get pulled over my a cop. The only way I can see it being legal is getting an Engineers certificate and modification plate and possiblying speaking to department of transport on whether this is enough or if the car has to be re-registered as a NA.

Dorigecko Proficient

Dorigecko

Posted
Posted
Haha are you serious? Man thats a big turn off lol. Thanks alot.

90% of these guys have popped a turbo hose. They'll tell you how gay that is.

It's the reality of dropping compression dude. Comp = power.

XRATED Veteran

XRATED

Posted
Posted
Yeah but I want a R32 N/A which in RB25 is quite a rare find. What do you think if I buy a RB25DE and drop it in a R32 GTST? Same story? Or more practical?

Just keep searching for an origional rb25de r32. Or if you really cant find one- swapping an rb20de for a rb25de is going to cost you the best part of $3k. If your going to keep the car till your off your p's, the rb25de is a great base for a high comp, mild turbo combination... While your at it you might as well throw some coilovers under it and a set of r33 gtst brakes.

If you do go for an engine swap and your keeping the car for a while, start with an r32 rb25de- as all the rb20 loom will plug in. Install a nistune into your rb20de ecu and tune it the best you can with intake and exhaust mods.

No more det to de! (we need bumper stickers)

WYTSKY Veteran

WYTSKY

Posted
Posted

to the OP, well done for actually doing a little bit of research and not just coming on here saying I want a skyline deturboed I dont care about power as long as there is a skyline and they end up with an illegal shitbox that wont take them up a hill...

Tell your mate there was a bloke on here that did do what he is proposing and after a couple of months couldnt take it anymore and had to put the turbo back on.

It is sensible to get a 33 rb25de and put it into a 32. Not sure on power to weight ratio / engineers of dropping a motor in, so there may still be a few legal issues there but no where near what you would have with a turbo motor. Only cops who a cluey about rb's will be able to tell the difference in motors, but engine number wont match the firewall plate im pretty sure...

Perhaps, just as piece of mind, look into how much it would cost to get a workshop to drop the motor in instead of your mate, probably will come with a few months warranty and if the motor shits itself you can take it straight back to them, instead of your mate saying sorry bud lets start again.

gl with it.

zebra Grand Master

zebra

Posted
Posted

FAIL - P-plates cant have turbo cars, cant have cars that have mods which require and engineers cert (which converting a turbo to non-turbo will need to have) etc etc,

Just buy a bloody non turbo skyline and be done with it

mad082 Grand Master

mad082

Posted
Posted

yeah just buy the non turbo one to start with. if it takes you 6 months to find one then so be it.

a deturbofied rb25det will be an absolute slug. the only way to make it as powerful as a rb25de is to raise the compression which requires a rebuild, so just raising the price even more. you'd be better off just buying a commodore because even one with 500,000kms on the clock that is falling to bits would be better to drive than a rb25det-t (det minus t).

and tell your mate he's an idiot.

iseekool Veteran

iseekool

Posted
Posted
9:1 compression in a turbo engine. 10:1 compression in a non-turbo engine.

If you've ever driven a hyundai getz, that's what you can expect from a deturbofied 25det.

A Hyundai Getz will be faster than a de-turboed RB25DET....

Guest
This topic is now closed to further replies.
 Share
Go to topic listing


×
×
  • Create New...