is a rb20det worth it?

[nicks-240]

i recently sourced a 240sx and want to swap the motor for something with alot more potential without breaking the bank with a rb26dett. car would be a daily driver / weekend drag car. i have researched the rb20det and read some pros and cons. and im confused on if its worth it? what are some power numbers some people have made with this motor and should i be worried about sourcing replacement parts , since its such an old motor and it was never made in the us.... please help with any input you have, thanks ahead

[DriftingisLame]

Yes.

My stock rb20 swap with a stock down pipe, and no cat/exhaust after, SAFC, and a FMIC, made 219 whp, and 200 wtq.

I made an exhaust from the turbo back, and then with the same setup ran consistant 13.6's @ 103.

This motor ran strong for 2.5 years, and finally died in 115 degree heat, because the 15+ year old intake manifold gasket wore out and leaked coolant into the intake port.

Buy an rb20, use an r32 crossmember, buy a complete OEM gasket kit. Replace the gaskets. If you really want to be thorough, do the headgasket, but its probably perfectly fine. Replace the coolant lines under the intake manifold.

Now your golden. This should cost you about $1500 for a clip, or motorset + crossmember, $150 for gaskets, $300 for a FMIC, $50 for an intake, $100 for elec fans, $200 for misc.

Probably $2300-$2500 for a good quality swap.

Your close to the cost of just the motor/clip for an SR, or RB25.

Good luck

[PorkChopExpress]

the power numbers on here seem inflated compared to the australia forum.they at a high elevation or being honest?

and get a r32 cross member like said. i have mckenny mounts and its janky. wish i swapped x member.

[Cjmartz2k]

RB25 is worth it, but not RB20 IMHO. I'd rather go SR20 (or even dare I say KA-t) over a RB20. Just my opinion. Just way to hard to get more than 400hp out of a RB20.

[DriftingisLame]

I'm not lying.

I dont know why it would be hard to get 400 hp. Its just a matter of large enough injectors and a bolt on t3/t04e, or whatever turbo setup you choose.

I think it would be really easy if you plan it out properly, and have the money to spend. The stock intake manifold is proven to 450+ hp, exhaust manifold has seen over 400 as well, Cams are good for over 400, the factory ECU is hella easy to remap. I dont see the difficulty, what is your reasoning? I'm interested...

Thanks,-Max

[PorkChopExpress]

not you personally, just in general seems the power levels on the skylineaustralia forums seem less.

sorry to hijack, but why do i see some people using safc on stock setups?

[DriftingisLame]

Look at the graph again.

The red line is before the SAFC adjustments, blue line is after. Look at how rich the stock fuel map is.

I gained horsepower and torque literally everywhere.

[Cjmartz2k]

Let me re-phrase. I'm talking about RWHP btw.

400rwhp is about what you can make on these motors, just not much more at all with out some serious work. The head doesn't flow for crap, and a RB20 would have a tough time spooling anything big enough to make much more than that below 5k RPM. Could you put a TO4r on an RB20? Sure. Would it spool before 6k RPM or make what the turbo is capable of? No.

Just look at the top RB20 performers on all the aussie forums. O yeah, and your not going to make 400rwhp on a T3/TO4e on a RB20.

There is not as much aftermarket support out there for the RB20 as the SR20, and the SR20 is a lot easier to get over 400rwhp.

[apollas]

honestly, when are you going to need a 400+whp car on a daily driven/ weekend car? on a 240 at least youre already breaking traction off of 400 already. imo any more than that is overkill. so for a daily driver/ fun weekend, yes its worth it. if youre serious about making any more power than that why go mid range, do an rb26 for that instead

[DriftingisLame]

Here's a dyno of carls I use for reference, this was way back in 2005

zerothread?id=133118

"not too much interms of mods:rb20dettomei 260/8.8 cams550cc injectorsgt30r turbo .63 arrun was done on 93 octane at 17psi, turbo is good for nearly 30psi i think the lean spoolup is causing the super late spool because its not really making alot of exh gas being so lean, once i get my biki rom i will add fuel there and see how that affects response."

Guess I dont have proof of a t3/t04e being able to make 400hp with minimal other mods, but seriously, I dont see why it couldnt. Carl's gt30 wasnt far off in size compared to most t3/t04e's.

Funny you mention a T04r, someone just posted one of those on SAU, 23 psi got 370rwkw (500hp). Pretty modded though. Full boost by 5500, anything over 23 psi apparently misfired.

http://www.skylinesaustralia.c...=1600

Another guy on SAU stuck a GT35R on his near stock rb20, ran 19 psi I believe and spun 293 rwkw.. Almost 400 rwhp.

If you read up on roy's setup on SAU he's running a td06-20g 8cm2 exhaust, making 260 rwkw (360 hp?), with killer response (stock intake, greddy exhaust/turbo, stock cams, stock head, unopened motor). That motor has also seen an 8200 rpm rev limit, and been running strong for YEARS with LOTS of abuse. There's a lot of raving on that site about the response of that turbo and other greddy turbo's.

I believe that anyone who's taken apart an RB20 like I have, will agree with me, this is built to be a durable motor. The rb20 has a large racing history and its standard internals will show you that, the ringlands are burly and are located way below the deck of the piston. The rods are nearly identical to rb26 rods (which have seen 950+hp and 1100+tq even with a longer stroke!), with a smaller big end. All of this combined with an incredibly short stroke insures the piston speed is low, and these components see little to no stress with higher RPM. I believe due to the low piston speed, the exhaust gas speed is slowed down which raises your full spool RPM, and your maximum torque RPM, I think this is why the motor is not quite as popular as the others. If you look at it with an open mind, what if your turbo hits full boost as late as 5000rpm (God forbid)? Well, you're blessed with a superior valvetrain that will support 8000rpm+ (stock), and you still have a 3000 rpm powerband. If you're judging a motor by its spool characteristics, consider the other factors, such as how far the motor revs safely, and how long you can consistantly see those rpms before something gives. I also never just look at how early the turbo spools, and what the peak HP is, seems thats all you ever read these days.. I'd much rather have 4000 rpms of useable power with 350 peak hp, than 2000 rpm of useable power with 400 peak hp.

Also, the head I believe is much simpler, more durable, and has far less parasitic drain than an SR head. In my experience our SR20 at school, the SR valvetrain (rocker arms specifically) cannot take much more than stock rev limit and power. If you compare the valve area between RB20's and SR20's, the RB still wins. My rb20 has a stock valvetrain and handles its 8200 rpm limiter quite well, and I'm not the only one who can vouch for this. If you think about it, The Rb20 valvetrain was used in all of nissans racing engines back then, RB20, 26, VG30, CA18.

As for aftermarket, sure, america has taken on well to the SR20 bandwagon. I for one would choose a superior design over ease of modification. SR's having more aftermarket is also only true to a point, you can find nearly any aftermarket part for the RB20, its just probably going to be a JDM brand, and probably expensive.... But those same JDM brands make just as expensive SR parts as well. The beauty of RB20's aftermarket is that its bigger brothers have tons of factory aftermarket to offer. RB26 cams degreed properly can be a great upgrade, RB26 injectors are nearly drop in, RB26 intake plenums (although require modification) make the motor much more visually appealing and easier to work on and gain some top end, rb25/26 crank/rods if you're complaining about spool characteristics and a lack of low end torque, I dont see why you couldnt adapt RB25 valves and such.

Okay okay, enough RB20 vs SR20 design and stuff... If there's one thing we all agree on, its that 99% of honda's, sound like SH1T!Absolutely TERRIBLE, Right?! But! if you've ever heard a well tuned B series honda coming at you at WOT, from 7000-8500 or so, it can sound really awesome, I mean, before it passes by and you have to hear the terrible farty exhaust noise. So there IS some good part about motors we all agree on hating... NOW, take away that one good think about the noises honda makes, and thats what the STUPID SR20 sounds like!! WTF!! And the more and more modded they get, they only sound worse!! I swear, its just a little deeper and louder, with the same crappy fart tone! It hurts my ears and disgraces the nissan name.

I'd take a 20 hp hit if I could hear Rb20 noises every time I get on it instead of SR noises. Damnit it makes me want to crap my pants just thinking about the noise.

Getting back on track, he never said anything about 400 hp. Which is why my first post consisted of my stock swap results. That swap beat 2 equally modified SR swaps by a decent margin.

I'm not trying to pick an argument with anyone, I just wanted to lay my facts on the table for the sake of helping the community.

Whatever route you choose, good luck.

-Max

PS: The RB20 sounds a million times better.

[DriftingisLame]

BTW, here's a picture of the Gibson R31's RB20. I believe it ran about 450 whp. Notice the standard inlet manifold. I was told it ran prep'd standard internals.

[Yellow4g63]

Sigh I wish nobody would reply to these threads. The guy is a troll asking a lame question. I'll tell you which 1 is better the 4G63 swap is better than them all or the Ej20 or B18c5 are better.

[Cjmartz2k]

If you have to ask what you would do with a daily driven car and more than 400rwhp, you wouldn't understand anyways

You do bring up two good points that I'll agree with. RB's sound a crap load better than SR's, and the durability with RB20's can't be matched (even in the RB26). My friend/shop guy tried hard as hell to break one for a while. I'm talking 9k RPM, 28psi, constantly banging it off the rev limiter kinda stuff and it just wouldn't break.

I guess my view is slightly skewed though by the fact I have cheap/easy access to RB25's (I'm in Japan). If/when I blow up a RB25, oh well. $300 + pizza/beers = fun weekend with friends and a fixed car. People underestimate (read Aussies) how strong RB25's are though. It's a lot easier to make 500rwhp on a stock (even the head gasket) than it is on a RB20. I'm thinking all out performance though, and can't appreciate the pain in the balls it can be to get stuff in the states.

[nicks-240]

Sigh I wish nobody would reply to these threads. The guy is a troll asking a lame question. I'll tell you which 1 is better the 4G63 swap is better than them all or the Ej20 or B18c5 are better.

ok.... a troll???? second, i picked up a 240sx .not a mitsubishi eclipse gst/gsx or a lancer evo, nor a subaru for there motors, or a civic chassis for a pre-k20 itr motor.... now thats addressed, the thread was created because of this thread zerothread/135400 and wanted to make sure it wasn't going to crap out on me 6 months into having it..

[Yellow4g63]

ok.... a troll???? second, i picked up a 240sx .not a mitsubishi eclipse gst/gsx or a lancer evo, nor a subaru for there motors, or a civic chassis for a pre-k20 itr motor.... now thats addressed, the thread was created because of this thread zerothread/135400 and wanted to make sure it wasn't going to crap out on me 6 months into having it..

It's a LAAAAAAAAAAAAAAAAAME question if you want to find out search it hell I even did it for you. Your 1st post which is better so I just told you which is better. Here is your RB20 vs SR20 info you needed zerosearch

[johnzm]

lol...

i got a 20, and im content.

making 220whp still with stock sidemount. (and no im not lying, i have about 20 pulls from 2 diff dyno's that both say 220whp)

its a hassle a sr is probably better in the long run, but the rb sounds pretty nice.

alot of people have stopped me to tell me how sick it sounds.

[nizmo zilvia]

I don't understand why people hate on the RB20. It isn't a bad motor. If anythings its under rated. But whatever. I'm happy with my RB although its caused lots of headaches, money, and time lol.