RB25det or SR20det in S30

[FastRabbit24]

So I am having that internal struggle on which route to go. I like the the thought of the RB25det but it is really heavy being cast iron, but can make allot of power and looks like it was made for the car. The S14 sr20det is light, can make allot of power and has allot of after market parts for it. They both pretty much cost the same around $2200. So between the two what would you guys recommend. Now I know there are other threads which I have read, but most of them are based on cash and compare other possibilities like the rb20 and others. I am only looking to do the RB25det or the S14 Sr20det. Your guy's input would be greatly appreciated on what route you would go and why.

Thanks

[kiwi303]

If you want it to go fast in a straight line, RB... more power, tim taylor type more power

if you want to go fast round corners, SR, lighter and further back in the car for better weight distribution and balance.

 

so what are you wanting to do? rip off others at the lights or the strip? or whiz round the hills like you're James Bond with a ferrari on your ass?

[73DatsunZ]

RB25. Do it. That is all.

[Armand]

It all depends on what you're using the car for. Like kiwi303 said, if you're planning on any sort of track use, go with the SR20. If you're just at the strip/street go RB25 all the way. Just the sound of those things at redline is enough to make your decision.

 

 

DROOOOOOOOOOL

[FastRabbit24]

Thanks guys. the car is not going to be used for the track or anything like it. Just building it to build it because I enjoy the build, and bring it out on nice days. I used to have s13 with an s14 sr20det in it and it was great. I am just having a hard time deciding. I am leaning towards the rb25det because it will be something new to me. But then I think about the pros and cons and I cant make up my mind. I was hoping that your guys input would help me out. If I go the rb route is there really a big difference in handling as compared to the sr20det?

[Daeron]

the difference is that between torque and horsepower.

[73DatsunZ]

I have heard that parts for the RB25 are going to be more expensive and slightly more difficult to get a hold of which makes sense seeing how the S14 is more popular for the demand for parts. But, If I were you I would go RB25, there is more displacement to make bigger power on, and its a new motor, you can have fun and learn some new things. But either way, both motors will be a good candidate, the Z is a light car, so it will move with either one.

[FastRabbit24]

Thanks for the input guys. I think Iam going to go the rb route.

[jc052685]

yeah, RB FTW

[73DatsunZ]

Sweet. When you get the RB post it up!

[FastRabbit24]

will do.

[LeX]

another vote for RB... I want to do that when I get another Z

[Kazumi3]

Vildini Motorsports in Mission Viejo California packed my Z with an RB25 DET. The firing order combustion sound is beautiful at idle and at full song. It is so smooth running. At night driving along the Pacific Coast Highway it's music to your ears. It's also beautiful to look at. Enjoy! Plan a SR20 DET with the second car. Go with the 6-cylinder with the first car.

[1 fast z]

If I see an SR powered Z at a show or something, I just walk on by, nothing speacial, four banger where a 6 used to be, just not for me. They will never make the power OR torque an RB would.

[ShaggyZ]

I realize he's made his decision, but I'd like to add one thing. While lighter weight does help a car's handling, is it necessarily true that a SR20DET install will handle any better than a RB install? I'm not so sure just removing weight from the front necessarily makes a better handling vehicle. I think the extra weight versus the SR20DET will be more than welcome in a raced Z because of the greater power potential and the fact that the weight and balance will be close (and probably better) with a well-installed RB.

[Armand]

The stock weight distribution is 52F/48R. With an SR20DET it becomes 48F/52R. Coil-Over's/new spring rates is a must.

 

"Brakes & tyres are everything... Lack thereof, there is no substitution, for weight"

 

-Mulholland Raceway, The Golden Rule

[Armand]

I realize he's made his decision, but I'd like to add one thing. While lighter weight does help a car's handling, is it necessarily true that a SR20DET install will handle any better than a RB install? I'm not so sure just removing weight from the front necessarily makes a better handling vehicle. I think the extra weight versus the SR20DET will be more than welcome in a raced Z because of the greater power potential and the fact that the weight and balance will be close (and probably better) with a well-installed RB.

 

As far as a Z being raced on a track, do you really need more power than an SR20 offers? There are people running over a year on 390rwhp on stock internals with no problems. Adrian from Vildini is getting 510rwhp out of this engine.

 

The 300lb difference between the RB and the SR is the biggest advantage you can ask for for a tracked Z. Off the top of my head I think that's a 12% weight savings, racers die for that.

[socal73HS30]

my vote would be RB.

 

and, Armand your car looks really sweet. mine's that stock z-orange and i thought it could never look good. yours makes me think twice. beautiful.

[turbostroker]

I am considering the same two options for my next swap, and after speaking to Adrian at Vildini I thought I was leaning toward the SR20 (light, durable, parts availability, ect), then he threw in another option...2JZ!, now i'm really tossed. My biggest problem with the 2JZ is that it's not NISSAN!

[1 fast z]

I tell you what, here in AZ, there are freaking 240sx's EVERYWHERE, and they ALL of Sr's in them. YAWWWWWWWWNNNNNNNNN. I hate being like everyone else, There are a few with RB20's, but VERY few with 26's. I would spend 3500 dollars for a 26 motor set, and be unique, AND will always have TONS more power pottential than the SR. I would go 2J, way before an SR. But then again, if I were to go Yota, I would go 1U, or if nissan, VK56. The sr is STILL a 2.0 liter, and when I have driven the SR's that I had driven in the past, under 15lbs, they are TERRIBLY slow, and to get up an moving, you have to work them so hard. Remember guys, its not about the max power you put out, or torque, its the area under the curves, thats what makes a car fast.