RB20DET vs SR20DET

[TTT]

hahahahaha Gary seems to be in a bit of a mood today..

are you chugging a pint every time you post the little toasting smileys on here??

hahaha

even better is cerealkiller's reply with his signature attached.

hahahahahaha

[Roy]

  GTST said:

...even better is cerealkiller's reply with his signature attached.

hahahahahaha

....

[yogi000]

hey sydkid........can i get my rb20 to be as torquey as a sr20 with the right tune??????

[rsx84]

you always see more s-13s with rb20det conversions over late model sr20det conversions but not very many r32's with sr conversions around ( though i did see my first one for sale the other day). i went rb over sr just for the dollars at the time.. RB half cut at $2200 is $2300 for fitting and mods rather than $4500 for half cut.....the 2 engines are very close on paper stock.....

[Maxx]

i started feel worry to post anything as i will think i say something wrong again!

u haven't mention the weight of the engine, i still think the SR is better due to the weight / size advantage.

As u say F1 is using V10, but not V12

thanks for teaching anyway

  Sydneykid said:

You are joking aren't you?

Horsepower = torque X rpm

So what if the SR has Xlbs more at 4,000 rpm, it's a dead duck at 7,500 rpm.  The RB20 is going strong to 9,000 rpm.  It's simple maths. There is no way an SR can produce 20% more torque than an RB, but the RB can rev 20% higher.  So the RB will always have more horsepower as long as everything else is equal.

Let's get down to the block issue, is there anyone out there who really believes that a standard SR alloy block can handle more boost than an RB20 cast iron block?  Like it or not, boost = torque.  So the RB wins again, it can handle more boost therefore it CAN make more torque.

This "SR's make more torque at lower rpms than RB's" is crap, any extra torque that an SR has is purely due to the tuning.  Take a look at the stated torque outputs of the various models of SR's.  The amount varies by more than 15% and the rpm by more than 20%, but they are all SR's.  The difference is in how they are tuned, not that the SR design is somehow inherently superior.

It's a self fulfilling prophecy.  You can't rev SR 's higher, so you choose  components (turbo size, cams, porting etc) and tuning that work within the rpm limits.  Oh wow it makes more torque at 4,000 rpm.  Dah, it has to, 'cause it won't rev.  If I tuned an RB the same, it would make the same,  But I don't have to, 'cause I CAN get the RB to rev withoit spending big bucks on the valve train.

I could also get into rod stroke ratios, main and big end bearing speed at rpm, valve area, inertia mass etc etc.  The bottom line is, for the same capacity, more cylinders = more horsepower.  That's why F1 engines are V10's, not V8, or V6's or I4's.  And nothing "shoots out of a corner" like an F1 car.

That'll get the SR lovers all stirred up.............

[Cubes]

The SR20 is a nice street motor as it has the torque where needed BUT does tend to feel a little out of breath at the top end.

Just when it starts getting fun you have to change gears.

The RB really comes in to its own once over 4500rpm.

RB= Race Breed.

SR= Street Racer.

haha lol

Torque wise.. I would agree with Max.. Off boost torque feels very similiar to the R33 RB25DET.

This really isn't so much the motor but I think has more to do with the cars weight and gearing. The S15's gearing is rather close where as the R33's are a little wider.

But really.. I would be very interested in driving an early model SR20 without any VCT.

Is there one without VCT?? lol

My personal opinion.. I don't like the 4cyl exhaust note.

Even if it was better I would stick with the 6cyl and make that better.

RB30DET.

[yogi000]

  Cubes said:

 

But really.. I would be very interested in driving an early model SR20 without any VCT.

Is there one without VCT?? lol

 

yeah the red top sr20 didnt have it

[Maxx]

  Cubes said:

RB30DET.

damn it, i want one, badly..

anyone want to take my S15?

[Sheriff Wan]

RB for sure.

I have driven both of them and yes the SR does pull from lower down yet once the RB is in its sweet spot it really outperforms the SR.

Aside from everything else the SR doesn't sound half as good as an RB at full noise.

[Cubes]

The RB20DET also feels like it has a much wider power band.

It always seems to feel like there is a gear to launch you out of a corner without over reving or dropping off boost.

Two different motors really. The RB I think would be much much better for track work.

[teejay]

id definitely go a rb

driven both, stock and modded, rb just feels more fun and alive

[Nameless EJ6]

You guys need to discuss this from another view point. The RB20 in an S13? S14? The weight of the R32 and S chassis is significantly different, of course the cars feel different. The engines are designed for the chassis.

The RB20 seems like an awesome engine. I've never had experience with one because I prefer displacement. I'd rather mod the RB20 over the SR however. Dun really prefer 4 cylinders..

[predator]

if you are talking R32.. the factory weight between an S13 and R32 is about 100kg.. its not insignificant, but its not massive.

S14/S15 is pretty much on par with R32 weight wise at around 1250kg

[Nameless EJ6]

heh, I stand corrected. Always thought the R32's were about 300 pounds heavier.

My s13 weighs 2590 pounds.

[Cubes]

2590 Pounds = 1170kg's.

Was that on a weigh bridge?

[Bazelinez]

The sr sounds like its dying over 6K, the RB wants more at 7K.... having owned both I do notice the slight low RPM dead spot in the RB however its something that can be driven around easily...... a small issue that's more then made up for in its other qualities

[Roy]

...meh 2.0L, they are too laggy! Give me a 427 with a powerglide:)

[Cubes]

Would you like a 427 with that fuel?

[funkymonkey]

  Cubes said:

RB= Race Breed.  

 

SR= Street Racer.

For f**k sake, if I hear another arseclown say RB = Race Breed/Bred I swear permanent bannings will be issued. Let me guess, VG in VG30DETT stands for Very Good huh?

As for RB vs SR, you shoud compare a 1991 SR engine with a 1991 RB engine. The RB20 design was altered slightly in 1991, and models of the SR after early 1993 were more advanced than the oldschool RB20 design.

Compare a 1999 S15 SR20 with a 1999 RB25DET Neo, not an RB20 from late 1993.

Just keep in mind the origins of nissan models... Skylines are family cars, Silvias are small passenger cars, and the true sports cars of the Nissan range are fairlady's... or zeds as you might know em.

Why did the RB20 not follow the SR20 and keep gettign designed? Because you could make an RB25 and get more power out of it of course without much loss in efficiency... make an SR any higher in capacity and it loses efficiency. Keep in mind RB engines going into non homolagtion models are meant to carry families around not become drift cars or quarter mile workhorses.

Also interesting to note is the RB20E kept being put into cars well into 2000, because it was the best bottom of the barrel RB engine you could get.

So in summary, the RB20 may not be as good an engine as a later SR engine... but that's only because the RB20 evolved into an RB25... and the SR20... well its still an SR20

Oh and V12 are used in race cars, they are just not within the rules of F1. Just like how they're trying to make them V8's soon... when or if it happens it dosen't necessarily make the V10 slower or a worse engine.

[Cubes]

  funkymonkey said:

For f**k sake, if I hear another arseclown say RB = Race Breed/Bred I swear permanent bannings will be issued. Let me guess, VG in VG30DETT stands for Very Good huh?

lol.

Are you serious or what?

I know I sure as hell wasn't.

SR = Street Racer.. lol yer right.