How to tell between RB20 and RB25

[IceSkyline25]

I have a S13 w/ an RB25 at least I was told that. But I post it a pic of it on this website and I was told that it might be a RB20 instead of an RB25 can some one help me tell the difference I'll post some pics of the enginge... Thanx..

[IceSkyline25]

here is another pic

[Eikon]

It's an Rb25 with Rb20 valve covers I think..

The 25 has that offset on the intake manifold for the 5th and 6th cylander runners.

*Err.. yeah.. i need to drink less.. Strike that.. reverse it.. RB20 has the offset on the manifold

That engine does have RB20 valve covers, but they are most likely transplanted.

How about some pictures of the front of the engine.. The sure way to tell is if the intake cam has the VVT lobe that sticks out similar to the cam angle sensor on the exhaust side.

[krayton]

It's an Rb25 with Rb20 valve covers I think..

The 25 has that offset on the intake manifold for the 5th and 6th cylander runners.

That engine does have RB20 valve covers, but they are most likely transplanted.

How about some pictures of the front of the engine.. The sure way to tell is if the intake cam has the VVT lobe that sticks out similar to the cam angle sensor on the exhaust side.

its a rb20. rb20 has the offset manifold. it just has a rb25 vavle cover. even using the rb20 ignitor iirc

but why ask questions, look at the block. its nicely printed there for you to read

[IceSkyline25]

Injectors

[IceSkyline25]

front end

[themadscientist]

It's stamped on the block man, look. drivers side (in the US at least) above the oil pan rail at the back of the motor. Those are 260 topfeed injectors so unless they have been changed it's either an RB20DET or an early RB25DE with a turbo put on it.

[Carl H]

rb20 in rb25 timing covers and valve covers.

[RB20DETodd]

rb20 in rb25 timing covers and valve covers.

the rb25 turbo i put on my rb20 did not have the fitting in the turbo compressor, i had to put it in. Tell the guy to give you 1k back then call it even. haha
Modified by RB20DETodd at 11:43 AM 9/30/2006

[lucky7]

lol @ honda radiator.

[OKRB20DET]

wasn't this motor already discussed in the show your motor thread?

[krayton]

wasn't this motor already discussed in the show your motor thread?

i think the guy is just double checking. it sucks to get scammed like that

[IceSkyline25]

I'll double check tomorrow on the block and post it. I hope I didn't get ripped of.....

[IceSkyline25]

It's stamped on the block man, look. drivers side (in the US at least) above the oil pan rail at the back of the motor. Those are 260 topfeed injectors so unless they have been changed it's either an RB20DET or an early RB25DE with a turbo put on it.

I took it to a shop in Houston and I was told that it had RB26 Injectors I don't even know anymore.....

[sil_eightyRPS13]

well then pull the timing gear cover off and see if it has VVTi...its not hard to mistake the two...the rb20 valve covers r FTL in my opinion...rb26s ones fit and look way better!!! and plus driving the two motors there is a huge difference in torque...a rb20 doesnt really start moving till after 4000+...

[Carl H]

those are redtop, std rb20 injectors 270cc.what computer is running the motor, the number off of it will tell all.

[skillzilla]

An RB25 ECU will run an RB20, just not very well.

[IceSkyline25]

Cams

[krayton]

dooood, why are you not just looking at the block so YOU can finally see

[gbaz77]

my dear rb20det brother. yes i said rb20det. check out this link, and you will see, the intake cam sticks out. this is actually what that lobe on the timing cover is supposed to cover.

zerothread?id=154424

if you look at your intake cam it does not stick out. its a shame that some douschebag would do that to you, but alas, he did. good luck on either getting some money back, or sueing him for some money back, since what he did IS actually illegal.

[IceSkyline25]

I did I didn't see anything the only thing is said is NISSAN JAPAN and it had the number 071 and then another nunber buy I check were you told me on top of the oil pan in the back I didn't see anything... ah so at last I know exacly what I have oh well at least it's an RB

[gbaz77]

like i said, you could legally get money back. its fraud, because he replaced parts to fool you, and you made an oral agreement to sell/buy an rb25, when in fact he sold you an rb20. it might be worth it if you can get 500-1000 back in small claims court to use for tuning etc.

[Carl H]

hell if it was supposed to be a 25 sue for the cost of a 25.the 071 block is a rb20 block...look right above the transmission bracket on the drivers side on the block, there will be a machined surface and on it the engine code stamped.

[IceSkyline25]

Well I'll look into it and thanx for all the help the other fu*k up thing he did he put the stamp that says what engine is in the car the plaque it says RB25DET..

[Joe]

Cams

RB20.

this is what the inside of a RB25 cam gear cover looks like

sorry man id go raise hell with the guy you purchased it from

[the_momo]

that really sux, sorry to hear that. but if you keep it, the rb20 will rev higher than the 25 (so im told, thats what ill be building soon) and an i-6 at 8k will sound great. sue for the difference, and build the 20.

[Joe]

great it revs higher

dosent change the fact it dosent make as much power. RPM does not equal horsepower

[300Plus]

great it revs higher

dosent change the fact it dosent make as much power. RPM does not equal horsepower

+5 lol took the words right outta my mouth Kamin

But to stay on topic, that really sucks man, tell us what you do and how the guys responds. hell post his phone number and email up on here and I'm sure fun will ensue

[Carl H]

rpm does equal horsepower...just not in a range you deem usable.

[krayton]

I'm sorry I made a threat. I won't do it again.