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Someone somewhere must know the exact differences with late RB20's . Variable cam timing and a shim type valve train would be worth having .

I'd also be looking at chamber shape and size because they changed on the Neo 25 - possibly be cause of emissions and detonation reasons .

How do the CR and power output compare R32 to R34 RB20s ?

Is there an engine manual available that covers all the R34 era RBs ?

A .

Mine does - it lists an RB20DE but there is no RB20DET.

A quick skim suggests the engines are very similar. The 25DE has the most compression - the 20DE has less and the RB25DET has the least.

My Stagea is quite heavy but so are most Skylines - I don't know why you'd bother with a 2Litre motor.

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Has a better head that flows almost what the 25 neo head does, solid lifters, VCT, basically it will be a shitload better than an oldschool rb20, it probably also has the compression increase that came with the rb25 so it should make a big difference, still why not just go 25 neo, win win!

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Has a better head that flows almost what the 25 neo head does, solid lifters, VCT, basically it will be a shitload better than an oldschool rb20, it probably also has the compression increase that came with the rb25 so it should make a big difference, still why not just go 25 neo, win win!

the rb20de neo costs around $1000 less then a rb25det neo.

plus the 9.5 1 compression ratio makes it a good choice for a affordable high comp street rb20 if you don't want to rebuild or go bigger to 25/26/30.

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Still can't see why anyone would go to the trouble of doing anything to an engine, even just swapping in one, and not upsize to a 25. It just doesn't make sense. The off boost torque of a 25 makes me wonder why I put up with a 20 in my 32 for so many years when I could have gone 25 at almost any time.

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some ppl might like the smaller motor for theslightly better fuel economy over the 25,with PULP being around $1.60 (most of the time) here in WA that might not be a bad thing

Edited by StevenCJR31
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But you see, they'd be wrong. I get much better economy with 25DET Neo transplanted into R32. The complete lack of off boost torque in a 20 is the killer, You end up wringing its neck all the time to try to make the car move with the traffic. 25Neo just wafts along on tiny throttle openings. It only uses lots of juice when you get right up it, which is perfectly acceptable.

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Just like women that its the beautiful thing about cars. There is enough variety around the keep everyone happy. I love my lil R32 GTSt complete with its RB20. I am hunting around for an R31 coupe and there is no way anything but a 9,000rpm RB24 is going to go into it.

WIht no cams, pistons, or rods the lil RB20 can punch out 8,500rpm and 310rwkws with a nice shape to the curve.

And for no other reason I was walking up to my car sitting in a back street after work on Friday, sun shining on its paint and I started giggling. After 13 years of owning my car I still smile when I drive it. I just love it....and cant wait to get back to PI and do this again

Its even more fun these days on E85 with another 35-40rwkws more then in that video

gallery_462_50_314527.jpg

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some ppl might like the smaller motor for theslightly better fuel economy over the 25,with PULP being around $1.60 (most of the time) here in WA that might not be a bad thing

Fuel economy between a 2.0 and a 2.5 RB? Really? Buy a Fkn push bike.

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I have to admit I went 20 before 25, only went 25 because the 20's electrics failed. I think theirs pros and cons with either of them. Power, 25. Torque 25, reliability 25. but as a 31 owner I do believe theirs a nostalgic f**k the cool kids about having a built 20 in one as it's what they were. And I think a Neo 20 would be awesome in a 31 but it's only a 1200ish kg car and they do alright with the old 20's in them anyhow. To me nothing beats the sound of a 20 with a gate on song but that might just be me...

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iwas going to put in a neo 20 in my laurel but the intake butterflies put the brakes on it... hell upset. was hoping to have a killer responsive unopened 300rwkw and 8k rev ceiling... have bought a rb25de neo instead... same aim 300rwkw unopened which is a walk in the park... only needs a det neo exhaust cam and we will be cooking. If only i had a 20 neo handy to play with.

hoping to find a 20 neo anyway so if anyone has some leads locally let me know.

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Just like women that its the beautiful thing about cars.

Just like a women you irrationally love your rb20 as well!

is there any chance a 20det plenum/runners/manifold will bolt up to the neo, or have you yet to find that out?

I'm guessing but the r33 25det intake and runners bolt up to the neo 25det, so the rb20 might be the same.

Edited by Rolls
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