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Hi all,

It has been posted quite a lot around the traps that the SR20DET is alot more responsive in the lower/mid rev range than the RB20DET (which is said to feel gutless off boost)... fair enough... but when i look at the tech specs, the torque figures are only 9Nm different and the the RB20 has max torque 800 rpm lower than the SR20.

i.e.

SR20DET 274Nm @ 4000 rpm

RB20DET 265Nm @ 3200 rpm

Wouldnt this suggest that (in stock form at least) the RB20 is better for daily driving as peak torque is earlier??

Call me crazy if you want, and there might be things i've overlooked or haven't taken into consideration or have just got plain wrong, but surely so many people haven't noticed this before??

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It has been posted quite a lot around the traps that the SR20DET is alot more responsive in the lower/mid rev range than the RB20DET (which is said to feel gutless off boost)... fair enough... but when i look at the tech specs, the torque figures are only 9Nm different and the the RB20 has max torque 800 rpm lower than the SR20.

The consensus of most long time owners (myself included) of SR20DET's is that the engines biggest point is its monster mid-range torque between 3500 and 7000rpm, under that, its a mild mannered grandma and after that its a wheezy grandpa :D

Wouldnt this suggest that (in stock form at least) the RB20 is better for daily driving as peak torque is earlier??

I found it fairly easy to live with a mildly tuned up SR20DET for over 7 years and no real complaints for that purpose around town as it functions perfectly well in a light car of 1150kg and running between 2000-4000rpm.

I don't have a lot of experience with the RB20's, but like most 6's they're usually much happier on highways where they can just roll around on low rpm at legal speeds with much less effort than a 4cylinder. Things like the weight of the car, mostly your R32's (while they're certainly not heavy, but still around 200kg more than a Silvia of the same era from memory) isn't that much of a factor in your fuel consumption as it is in stop-start traffic.

Having owned both...i find that its partly due to the power delivery characteristics of the engine too...the RB is so smooth and creamy and pretty linear in stockish form whereas the SR feels rough as sh!t and alot more urgent...the SR seemed happer from 2500-5500rpm and the rb seemed happier from 4000-7500rpm...the characteristics of the SR makes it nicer to drive on the road...trackwise i prefer the RB...

SR has a more sudden surge of power. As said, the RB is much smoother. I think a lot of people mistake the feeling of torque in the SR's with how light the Silvia's are. Try putting the SR into a Skyline. It makes a world of difference.

Having owned both...i find that its partly due to the power delivery characteristics of the engine too...the RB is so smooth and creamy and pretty linear in stockish form whereas the SR feels rough as sh!t and alot more urgent...the SR seemed happer from 2500-5500rpm and the rb seemed happier from 4000-7500rpm...the characteristics of the SR makes it nicer to drive on the road...trackwise i prefer the RB...

most obvious of the above is what a friend and I did back a few years ago.

he had just modified his S15 (had about 190rwkw) and my R32 gtst was with the usual mods making 150rwkw or something.

we had a one way street at the back of our work where the left side is a wall and the right side if the building we work in.

long story short, we went in each car one at a time.

roll start, plant foot in 1st and second etc.

the S15 gets to about 3000rpm, spins wheels to about 5000 rpm, then traction, then shift at 6500rpm.

in the skyline, gets to about 4000rpm, spins wheels till I shift at 7000rpm.

skyilne was definitely slower less power etc, but the power delivery was very different between the 2.

the rb just wanted to keep climbing.

the SR wanted to be shifted to next gear.

The specs on paper don't make much sense when you've driven both.

you think that they have to be wrong.

i think a lot of it has to do with the feel of the 2 engines, the 4cyl engines tend to feel more responsive (for obvious reasons), this gives the feel of whats sometimes mixed up with torque. ive driven a few CA's and SR's, and with less power, more power, or bigger turbo, stock turbo, they always tend to feel more "torquey" than my RB20 until u realise the revs arnt really climbing that quickly.

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