Engine Swap

[shoebox]

Has anyone tried putting a RB25DET engine from an R34 GT-T into an R33 GTS-T Series 2?

What do you think about it, and is it simple? What's needed to be done in such a conversion?

Can I continue to use the R33's ECU or must I replace it with an ECU from an R34?

The reason why I need to do this is because my current engine is in need of a rebuild or a replacement... *sigh*

Tried searching the forums to no avail... apparently no one has done it before, or it's too insignificant to be mentioned (?)

Thanks in advance!

[Wink]

People don't do it because the performance difference between the R34's RB25DET NEO and the R33s RB25DET is minimal.

If I were you I'd get a RB25DET from a R33 instead and pocket the difference.

[Modena]

People don't do it because the performance difference between the R34's RB25DET NEO and the R33s RB25DET is minimal.

If I were you I'd get a RB25DET from a R33 instead and pocket the difference.

Good points.

[satanic]

LOL; the performance difference is minimal - arguable

RB25DET NEO and RB25DET are two different things; there's heaps of differences between the two. And these days; the cost of either one is about the same.

[shoebox]

The cost difference is about 1.5 to 2k, but the real reason why i'm thinking of doing it is to have the power of an R34 in an R33... especially after my R33 engine needs replacement.

As far as i can see, they're both the same engines with the same wiring diagram, except that the RB25DET NEO has a NEO head, and power difference is about 22kw.

[satanic]

Have a read of Abo Bob's NEO thread - it'll show you that the R34 motor is a lot more than a R33 motor in many ways

but then; "People don't do it because the performance difference between the R34's RB25DET NEO and the R33s RB25DET is minimal"

[N1GTR]

Why have one turbo when you can have 2?

RB26

Or if the budget doesnt stratch that far, use your existing RB25 head/turbo etc and get an RB30 bottom end (cheap as)

There are heaps of people that have done this and have done it on the cheap, also the power levels seem quite good

Read this

http://www.skylinesaustralia.com/forums/in...t&p=1920659

[shoebox]

Why have one turbo when you can have 2?

RB26

Or if the budget doesnt stratch that far, use your existing RB25 head/turbo etc and get an RB30 bottom end (cheap as)

There are heaps of people that have done this and have done it on the cheap, also the power levels seem quite good

Read this

http://www.skylinesaustralia.com/forums/in...t&p=1920659

Yea.. my budget doesn't stretch that far, or i'll be doing the GTR conversion already!

I thought of getting an RB30/25 hybrid conversion too, but RB30 engines are pretty old at this point in time, and i'm kinda concerned about reliability.

I agree about the performance difference though, but i rather have a newer engine than save that bit of money and end up with an exact same old configuration as before.

[N1GTR]

Fair enough

If you plan to build one with forged internals the prices have come down a lot lately for the parts which should help you out money wise

[shoebox]

Yea but i don't think i'll be going the forged internals... a bit too expensive

Hmm.. back to the original question.. has anyone done it before?

Is it as simple as fitting in a RB25DET from an R33?

[ronnydotk]

Yea but i don't think i'll be going the forged internals... a bit too expensive

Hmm.. back to the original question.. has anyone done it before?

Is it as simple as fitting in a RB25DET from an R33?

a mate of mine did the RB30 with RB25 head and he's not looking back. although he did it into a VL so i'm not sure how easily the 30 block goes into a R33 bay.

as far as the NEO or standard R33 25DET they should all mount onto the same cross member without to much fuss, if anything you may need to swap the engine brackets over to the old R33 RB25DET ones if you go the neo option.

i'll go in favour of the NEO conversion.

[shoebox]

a mate of mine did the RB30 with RB25 head and he's not looking back. although he did it into a VL so i'm not sure how easily the 30 block goes into a R33 bay.

as far as the NEO or standard R33 25DET they should all mount onto the same cross member without to much fuss, if anything you may need to swap the engine brackets over to the old R33 RB25DET ones if you go the neo option.

i'll go in favour of the NEO conversion.

Yea, Mercury Motorsports just did it for me. I'll be putting the before and after dyno results up and probably some other information in case someone's thinking of doing this too.

[Atreyu]

There is a thread on doing this swap, not sure which member did it but it goes through all the differences you need to make. Yes you need to use the R34 ecu. The wiring loom needs to get changed a bit and if I can remember correctly he took it to a workshop to get the wiring all done/spliced.

Personally I think its a worthwhile swap and cheaper than 26, 25/30 etc.

[shoebox]

There is a thread on doing this swap, not sure which member did it but it goes through all the differences you need to make. Yes you need to use the R34 ecu. The wiring loom needs to get changed a bit and if I can remember correctly he took it to a workshop to get the wiring all done/spliced.

Personally I think its a worthwhile swap and cheaper than 26, 25/30 etc.

There might be one, but i can't find it... anyone knows?

From what i heard, i can continue to use my current ECU from my R33, but we'll see..

[Atreyu]

I believe you need to use the R34 ECU... Its different to the R33 ECU. They are different motors. Heaps of differences on them.. Sensors. etc etc.

You only got the car less than a month ago and its stuffed already? Thats the question Id like to know.

Edited November 6, 2006 by Atreyu

[shoebox]

I believe you need to use the R34 ECU... Its different to the R33 ECU. They are different motors. Heaps of differences on them.. Sensors. etc etc.

You only got the car less than a month ago and its stuffed already? Thats the question Id like to know.

Yea. Apparently the bearings inside my current engine wore out and i either rebuild it or i change the engine. There was this dull, thudding sound coming from the engine which increases with the RPM...

I havent even done anything to the car yet =_=

[shoebox]

<.

[shoebox]

Finally got back my car a few days ago, and was driving it around.

The following were already fitted before the conversion:

XForce turboback exhaust system

The following things were then put on:

RB25DET NEO engine transplant

Spitfire coil packs

Apexi AFC Neo, RSM

Trust VSPL intercooler

Greddy profec b spec 2 boost controller

As far as the engine conversion is concerned, it appears that these two engines are really quite different, so it involves quite a fair bit of re-wiring, a new crank angle sensor and a few other things which i can't remember. As Arteyu has pointed out, it is quite a different engine, and contrary to popular belief, it's not just the cam heads which are different. However, you can continue to use the R33's ECU.

The guys at Mercury Motorsport did the changeover and tuning, and the power jumped from 141kw to 205.8kw. If anyone is interested in doing this, you might want to give them a call at 1300 558 650 to find out more.

Car's pretty responsive. No complains so far, and they did a pretty good job IMHO.