Jump to content
SAU Community

Rb30 Block Specs (from Fsm)


Recommended Posts

One thing i'll say, is that these 'one off' projects, do end up getting extremely expensive quite quickly, as most of the gear will be custom made or modified, and you'll find urself buying 2 or 3 things over to end up with the right combo.

All in all i cant wait to hear what its gonna sound like, and im sure it'd be an intruiging project :(

Link to comment
Share on other sites

it all sound great but with only 94 octane gas I would be going for 10 or 10.5:1. and definately be looking at much higher lift cam shafts. for a high revving 3 litre NA I would be speding lots of money on the head/cams etc as without a turbo these are going to dictate how much power it makes, and what the engine is like to drive.

Link to comment
Share on other sites

One thing i'll say, is that these 'one off' projects, do end up getting extremely expensive quite quickly, as most of the gear will be custom made or modified, and you'll find urself buying 2 or 3 things over to end up with the right combo.

All in all i cant wait to hear what its gonna sound like, and im sure it'd be an intruiging project :(

well, the only thing i can see getting in the way is having to buy custom pistons, a selection of headgaskets and doing custom head work.

the exhaust is going to be made by myself, and would cost the same or even less than a turbo manifold that is built well. I've got the flanges already.

i dont think the rods will need to be modified, and the belt is still up in the air (as no one has replied to my Gates Powergrip GT2 belt thread with any success stories, all hearsay).

The reason why I'm asking a lot of questions, as you all know (by looking at the board index for the passed day or two) is so that when it's said and done, I don't end up buying 2 or 3 things over again, as you stated. LOL

Link to comment
Share on other sites

it all sound great but with only 94 octane gas I would be going for 10 or 10.5:1. and definately be looking at much higher lift cam shafts. for a high revving 3 litre NA I would be speding lots of money on the head/cams etc as without a turbo these are going to dictate how much power it makes, and what the engine is like to drive.

Indeed.

I want to get the bottom end buttoned up first, then I'll get some more money over the winter to button up the valve train and make some real power with the Wolf V500 unit that i'll hopefully be getting.

and the piston to valve clearance is going to dictate how tall a cam I can use as well, so I'll be looking at that carefully.

I think 11:1 is the safest bet for me, however 10.5:1 isnt a huge decrease in power, but for an N/A, i guess you could say it is.

thanks for the heads up

Link to comment
Share on other sites

Any chance of some videos of this puppy once its going ? maybe some pics as well. Would be good if you could keep us posted on this project.

absolutely. even mid-build =)

i ask that you pay no attention to the Canadian accent (if any), ahead of time :(

Link to comment
Share on other sites

yeah anything over 10:1 will give you a pretty lively 3 litre. but seriously look at much bigger cams. 264/8.7mm will not be near enough to give it some real power up top. especially look for more lift. for a powerfully NA motor that is capable of decent revs it's not uncommon to go up around 300 degree duration and 12mm lift (not saying you would go that far, but you get the idea).

Link to comment
Share on other sites

ohhh no problems.. its just the guys down south that can get annoying at times =)

absolutely. even mid-build =)

i ask that you pay no attention to the Canadian accent (if any), ahead of time :(

Link to comment
Share on other sites

yeah anything over 10:1 will give you a pretty lively 3 litre. but seriously look at much bigger cams. 264/8.7mm will not be near enough to give it some real power up top. especially look for more lift. for a powerfully NA motor that is capable of decent revs it's not uncommon to go up around 300 degree duration and 12mm lift (not saying you would go that far, but you get the idea).

In due time, Baron.

Once I take the head off for it's 6 to 12 month inspection (provided it works as planned) I'll do up the head with some larger valves, stiffer springs, and taller/wider cams.

Then I should make real power.

For now, keeping it mid-range isn't going to dissapoint me. I know there's a lot more to be had in terms of power by doing extensive head work. But I have to take things one step at a time, and these hks cams that I got will allow me to make some money back when I sell them to someone with a mild skyline that they want to upgrade at a later time as well.

Cheers. ;)

Link to comment
Share on other sites

  • 3 weeks later...
  • 4 weeks later...

Hi , I'm unbiased with manufacturers so I'm curious to know a few things .

Firstly is the car going to be a Nissan ie Skyline or is the drawcard having a large capacity RB engine for its own sake .

The reason I ask is that it seems Nissan never intended the RB30 to be a high performance engine so there never was a twin cam head developed for it . I think the greatest limiting factor is going to be getting enough air in and exhaust out even with a modified RB26 head , the 3L brings obvious torque potential being ~ 20% larger but to make power at revs it has to breathe and with only atmo pressure to charge the cylinders I'm not sure if its possible to get enough valve and port area into an RB26 head .

If you have choices there are other alternatives like 2JZ's and BMW etc straight sixes that are probably a bit less compromised than an NA RB2630 . Actually thinking about it if you look at Nissans V6's the bore was larger and the stroke shorter (ie VG30 is I think 83 stroke/87 bore) which in theory gives greater breathing abilities (can fit larger valves in greater sized bores) and the shorter stroke possibly means less piston innertia . The VG30 by todays standards is bulky and heavy and the VQ30's would have some design updates over the old 4 cam twin plenum VG30 . I'm pretty sure a few years back there was some form of VQ30 based competition engine and its results were very good . If it were me I'd research those before I put a lot of resources into a hybrid RB30 - particularly an NA one .

Factory engineering is often hard to beat from a costing point of view so if you can benefit from their R and D so much the better .

More than one way to crack the 3L nut , cheers A .

Link to comment
Share on other sites

  • 4 weeks later...
Hi , I'm unbiased with manufacturers so I'm curious to know a few things .

Firstly is the car going to be a Nissan ie Skyline or is the drawcard having a large capacity RB engine for its own sake .

The reason I ask is that it seems Nissan never intended the RB30 to be a high performance engine so there never was a twin cam head developed for it . I think the greatest limiting factor is going to be getting enough air in and exhaust out even with a modified RB26 head , the 3L brings obvious torque potential being ~ 20% larger but to make power at revs it has to breathe and with only atmo pressure to charge the cylinders I'm not sure if its possible to get enough valve and port area into an RB26 head .

If you have choices there are other alternatives like 2JZ's and BMW etc straight sixes that are probably a bit less compromised than an NA RB2630 . Actually thinking about it if you look at Nissans V6's the bore was larger and the stroke shorter (ie VG30 is I think 83 stroke/87 bore) which in theory gives greater breathing abilities (can fit larger valves in greater sized bores) and the shorter stroke possibly means less piston innertia . The VG30 by todays standards is bulky and heavy and the VQ30's would have some design updates over the old 4 cam twin plenum VG30 . I'm pretty sure a few years back there was some form of VQ30 based competition engine and its results were very good . If it were me I'd research those before I put a lot of resources into a hybrid RB30 - particularly an NA one .

Factory engineering is often hard to beat from a costing point of view so if you can benefit from their R and D so much the better .

More than one way to crack the 3L nut , cheers A .

Good info, but I'm sure you understand when building a fun project is just something you'd like to try. Regardless of it's outcome. Heck, I could always either just increase gasket height or install new pistons down the road, and turbo it again. That's not an issue with me.

And in regard to air intake and exhaust, you're probably right that there are better alternatives. But then again, if I REALLY cared to have the ultimate best for a Z, I would have gotten an LS7 or something and installed corvette C4 suspension all around, and done something like that.

And regarding the bore size, my pistons are 87 mm anyways. It's the stroke that is going to be interesting. The engine is almost square in terms of bore stroke. We'll see what happens.

I just got my engine back from a person who I thought was a machinist, but infact he's just a builder. I'm taking it to a machinist who is closer now, and I'm actually going to start getting things done. All I have to buy is the balancer, flywheel, and bearings, and then I'm ready to start giving the machinist some parts.

Again, I'll keep you guys posted.

I'm just building it to see what I can do with it, that's all to be honest.

And agian, it's not going into a skyline or anything big like that. It's going into a small datsun 280z :)

you guys call em 260z.

Edited by Careless
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share



  • Similar Content

  • Latest Posts

    • Much less twat-tastic. CF wheels are too garish for civilised use.
    • From there, as the manual says....assembly is the reverse of disassembly, no tricks worth mentioning Much better (for me)
    • In my case, the standard wheel I had was in good condition but the buttons had more wear, so I swapped them across from the original wheel from the car. The plastic rear cover is held on by 4 tabs, and once the wiring is removed you can get access to 2 screws on each side the hold the buttons in From there I just swapped the wiring over. What was interesting is the standard style wheel is 2.0kg but the carbon fibre one is 50% heavier at 2.9kg. It even has a weight inside the wheel at the top to make up for some sort of imbalance in the design. weird
    • Once the airbag is off, to remove the steering wheel.... Undo the 2 plugs into the clock spring, and the horn connector from it's clip. Hit the 19mm nut with a rattle gun (preferably) or if you don't' have one, you probably want an assistant to hold the wheel in place while you use a breaker bar to undo the nut Then, screw the nut back on 3 turns, and pull the wheel sharply towards you. If that doesn't work hit it medium force with a rubber mallet on either side, or possible behind if you can get there. If that all fails (it shouldn't!) you might need a steering wheel puller
    • So, to next task....the carbon fibre steering wheel was either an expensive factory option or a chinesium special. Either way, I don't like either the flat bottom or thick ring style, so it had to go So...to remove the steering wheel.... First, disconnect battery negative and stomp on the brake pedal for a few seconds. Then, remove the small circular covers on each side of the wheel's rear surround to uncover the airbag clips. You need to push something like a flat bladed screw driver through, to push the steel clip inwards and pull the side of the airbag forward. Once you've done the easy side, same on the centre console side. You can see the tab you are shooting for circled in red Then, disconnect the horn spade connector and for the yellow airbag plug you need to get something small under the black locking tab to pop it out, then the connector releases......airbag is off  
×
×
  • Create New...