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Hi guys! just about too finish my rb25de conversion on my 32, and i'm quite keen to run ITB'S on it and i don't really know whats needed to go ahead just wanted too see who has done it and

-What parts are needed

-How much roughly its going to cost

-If its actually worth the time effort money

I know people say N/A's are a waste of time ect But i do have a track car thats fully built and i'v seen some n/a weapons that are, plus its my daily!!

Thanks heaps!!

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Ok back in a state of not so much intoxication, there is actully a few threads with guys that have done RBs with itb set ups one being I belive greg maybe with a 26/30 set up with itbs and the other an rb20 race 32.

Can it be done, yer sure. You need a custom inlet manifold to mount them to and obviously 6 itbs, a decent aftermarket ecu and general fabrication skills help if your doing it yourself as alot of the stuff will need to be made custom for your car.

Also going to rephrase what I said in the earlier post (also as Simon has pointed out), NA performance isn't a waste of time, so good results are achievable but on RB motors making any kind of mind boggling power is practically unattainable no matter how much cash you throw at them, for example gregs only made ~170rwkw, which is all well and good until you consider the fact that the motor and all the fab work has cost a small fortune and your still going to get chopped left right and centre.

Can it be done, hell yer it can... Is it worth it, I don't believe so, it does look/sound cool though and it's something different :)

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Do it for a point of difference on a roadcar yes, but don't expect any instant gains from it.

The build aspect is fairly easy if you have access to a CNC machinist that can make the adapter plate and weld to what's left of your intake manifold. The secret here is what intake runner length you end up with as to how it perfoms and this varies on what other mods you have.

I built my ITB engine for a specific class of rallying. I wanted to skid an R32 and have the reliability of an RB to run in a 1600 - 2000cc capacity class. (note a turbo would put a 1.8 multiplyer on my cc rating) It took a few years of tuning and tweaking, but four or five years on it is making easily over 100hp/litre, has great throttle response and is very competitive.

I wouldn't be so keen to have my setup in a roadcar (especially a daily driver) as it just isn't that drivable in traffic. Most of that would be down to the cams I run and the fact it is tuned to function in the 5,000 - 9,000rpm region. 1,500 - 3,000rpm just isn't any fun surging along.

If you outsource the work, yes it will cost you a bunch of cash.

It will never make hp/litre like a Honda.

It will sound cool.

PM me if you are interested in details of the setup I run.

rb20deitb.jpg

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  • 4 months later...

Digging this topic back up, a guy i know has an itb kit made to suit an rb25 which he says should just bolt on. Does anyone know what else would be needed to get these running on an rb25de series 1( the previous owner said it was a series one rb25de but i'm pretty sure it has vct:S)?

id be planning to run these with a nistune ecu and a set of 264 degreee cams, would you really see a worthy gain? i would be running these with an rb26 plenum not the velocity stacks.

http://www.ebay.com.au/itm/Nissan-Skyline-RB25-RB26-ITB-Adapter-Kit-Complete-kit-ready-to-bolt-on-/281127320647?pt=AU_Car_Parts_Accessories&hash=item41747e7c47&_uhb=1

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In a nutshell:

$$$$$$

Cool Sound from intake

Still a terrible sound from exhaust

Slow

Torqueless

Boring to drive compared to a turbo car even though it has mad ITB sound

Money spent will make you depressed a month after driving it realising you built a slow car that makes a throaty intake noise lol

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its had a series one r33 RB25DE swapped into it at some point in time. yea i know turbo is the way to go if you have the choice, but am on a P plates at the moment, so not really an option. Definitely on the cards once i get my full licence.

Had a bit more of a look into it and i don't think it will really be worth the effort, going from an rb25 plenum to an rb26 plenum is going to kill the low end response due to the short inlet runners, plus will have to change the TPS sensor and a bunch of other stuff. Think ill just leave it to cams and a nistune and leave it like that till i get my full licence.

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  • 2 weeks later...

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