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Hey all,

Sending my engine to the machinist this week, and I need some block specs.

anyone got the pages that I would require for the machinist to do the works on my engine?

RB30 block with 26 head if it matters. Mild street engine with light track duty. N/A, not turboed.

High RPM, High Compression (11:1 if i can)

anyone got the pages I need and can scan?

Thanks a ton!

Raff

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Not to be rude, but the machinest shouldn't need any paperwork, what spec is he after? You will have to bore it to suit the pistons, which would have to be special orders, as i doubt you could deck the rb26 head to achieve that sort of comp, youll need pistons with big crowns.

If the rb30 rottom end is standard(not rebuilt) i wouldn't go much past 6500, especially if it doesn't have a crank collar.

Not to be rude, but the machinest shouldn't need any paperwork, what spec is he after? You will have to bore it to suit the pistons, which would have to be special orders, as i doubt you could deck the rb26 head to achieve that sort of comp, youll need pistons with big crowns.

If the rb30 rottom end is standard(not rebuilt) i wouldn't go much past 6500, especially if it doesn't have a crank collar.

so with a full foreged rebuild, whats the max "safe" it can handle.

Not to be rude, but the machinest shouldn't need any paperwork, what spec is he after? You will have to bore it to suit the pistons, which would have to be special orders, as i doubt you could deck the rb26 head to achieve that sort of comp, youll need pistons with big crowns.

If the rb30 rottom end is standard(not rebuilt) i wouldn't go much past 6500, especially if it doesn't have a crank collar.

agreed

so with a full foreged rebuild, whats the max "safe" it can handle.

8000rpm with all the good gear

so with a full foreged rebuild, whats the max "safe" it can handle.

How much power do you want

What turbo?

What cams?

etc etc. All these determine how high the RPM needs to be and then the motor is built accordingly.

You really shouldn't need any more than 7500 :D

nismoid i believe he said it was going to be N/A. no turbo, cams well who the hell makes a 26/30 na anyway? Thats the silliest thing ive heard.

for a technical forum you have some quite rude comments to make about peoples choices in what they desire to do/build.

not once did i ask for any of your input on whether or not it would be a good idea, and you also don't know the situation that every person on this forum is in, therefore, i find it poor judgment on your part to be slandering any future build plans that anyone has on this forum just because you don't like it. whether you've built an insane-oh RB30 with a turbo larger than a watermelon, or whether you work out of your garage building miniature v8's. it's all the same shit, and I don't really care for negative comments.

I find it funny how when SydneyKid lists what he would do to an RB30 with a full list of parts, and what car he would stuff it in, everyone seems to go WOW THAT SOUNDS AWESOME.

yet, when I start an engine build (with some help from cubes and sydneykid himself), and decide to put it in virtually the same car that sydneykid mentioned, it suddenly becomes taboo? get real man.

the fact that we're here and we're all building engines should be enough to warrant some kind of an applause, rather than some childish remark like that.

Not to be rude, but the machinest shouldn't need any paperwork, what spec is he after? You will have to bore it to suit the pistons, which would have to be special orders, as i doubt you could deck the rb26 head to achieve that sort of comp, youll need pistons with big crowns.

I, myself, am after the bottom end clearances and such. I have the manuals for the R32, 33, 34 RB25 and 26 engines for all generations.

However, I do not have an RB30 FSM so I can't be sure of what to use as a proper clearance for connecting rod, and main bearing clearances and all bottom end parameters.

if someone can supply that, I would appreciate it quite a bit.

Hey man

maxium respect to you, I completly understand your position as I'm having to do the same thing.

Good luck with your build, I'm sure I will be asking you some questions one day when I deceide to build my RB30/26.

I really wish there was an online teleporter device that could port you and thread craper to a boxing ring so you can knock the shit out of some people I swear.

Anyways man take it easy man.

nismoid i believe he said it was going to be N/A. no turbo, cams well who the hell makes a 26/30 na anyway? Thats the silliest thing ive heard.

wanna find out what kisin is talking about then?

Having a turbo motor in his car, i made the assumption he was going 26/30-turbo.

Because i was replying to that part of the thread (being that i quoted him) :(

Hey man

maxium respect to you, I completly understand your position as I'm having to do the same thing.

Good luck with your build, I'm sure I will be asking you some questions one day when I deceide to build my RB30/26.

I really wish there was an online teleporter device that could port you and thread craper to a boxing ring so you can knock the shit out of some people I swear.

Anyways man take it easy man.

Thanks SysLink.

I wouldnt mind if you asked questions at all. Hence why im trying to ask people here what to do in regards to bottom end prep. I want my engine to be within the best possible shape before assembly.

Good luck with your build as well, and thank you for the support.

Now does anyone have an RB30 FSM that they can either send me, or pull some pages from and scan?

I don't think there is anything perculiar to the RB30 engine. the engine builder should have a pretty good idea of what to aim for with the bearing clearances for a performance engine. the piston to bore clearance will most likely be stipulated by the piston manufacturer. remember that any "RB30 specs" you do get will have been written with the intention of the motor being used in either a forklift, a low power low rpm NA, or a low boost fairly low power turbo set-up so they may not be suitable for what you want from the engine/car anyway.

and personally I think an NA RB30/26 will be kick ass. but if it were me I would have scrapped the RB30 part and just build a nuts high comp RB26, or maybe even RB28. now you must post some sound files of it when it's done. I want to hear this thing at 8500rpm!

I don't think there is anything perculiar to the RB30 engine. the engine builder should have a pretty good idea of what to aim for with the bearing clearances for a performance engine. the piston to bore clearance will most likely be stipulated by the piston manufacturer. remember that any "RB30 specs" you do get will have been written with the intention of the motor being used in either a forklift, a low power low rpm NA, or a low boost fairly low power turbo set-up so they may not be suitable for what you want from the engine/car anyway.

and personally I think an NA RB30/26 will be kick ass. but if it were me I would have scrapped the RB30 part and just build a nuts high comp RB26, or maybe even RB28. now you must post some sound files of it when it's done. I want to hear this thing at 8500rpm!

well the thing is, I have a friend who imports RB30's, and He also was going to build one for himself, but he decided to scrap the idea, and he's left with a blown RB26 that has a good head and all the sensors and gadgets i need, and it's half the price of a regular GTR engine, and he's tossing in some HKS cams and cam gears as well. So it's a little hard to pass up, and i want all the displacement I can get. :D

so you guys mean to tell me that there are no specs to look at when assembling this engine? surely the FSM has some data to use. there are literally thousands of engines on the planet, and each of them has somewhat different clearances, I doubt my machinist would just "know"

I'd feel much more comfortable going with stock settings and adjusting them to the high side, rather than going out on a whim with what to use for clearance..

so ideally, if someone can scan those pages..... :(

Edited by Careless
However, I do not have an RB30 FSM so I can't be sure of what to use as a proper clearance for connecting rod, and main bearing clearances and all bottom end parameters.

if someone can supply that, I would appreciate it quite a bit.

post-8303-1183581038_thumb.jpg

That should help with the bearing and tunnel sizes. If you work to around .002" clearance on both the mains and conrod bearings and around .004" end float you wont have issues. Unless the crankshaft needs to be ground, just polish it. The main bearing tensions are the same as an RB26 and if you're not using aftermarket rods, fit a set of ARP VG30DETT rod bolts. You will need to trim the length of them to clear the cradle. It's a good idea to fit an RB26 oil pump as well as a drive collar while you have it apart. Apart from that the bore size is 86mm standard, the same as the 26. What are you doing to get the compression up to a decent n/a ratio? You could run an RB26 piston and deck a fair bit off the head which will get you well up in the 9's, all depends how much you take off the head. If you're using an RB20/25 sump you will need to bend the little baffles at the rear to clear the conrods when they rotate.

I hope this helps

Cheers,

Greg.

oh yes oh yes!!!! a high comp 26/30 NA.

i'd want to try and bump the 11:1 up a little more if possible (may as well :w00t:)

and be sure to have trumpets

RB30 block and crank

3.1 litres

13.5 to 1 compression ratio

Polished combustion chambers

272 duration 10.8 mm lift cams

Titanium retainers

Tome valve springs, 55 lbs at the seat

2 mm oversize inlet valves

1 mm oversize exhaust valves

Ported RB26 cylinder head

Ported RB26 inlet, multiple throttle bodies and plenum

Tuned, coned collector extractors

4" titanium exhaust

JE forged pistons

Carrillo rods and rod bolts

ARP main bearing studs

ARP head studs

ACL race series bearings

N1 oil pump, with wide flange drive crank collar

RB26 water pump

Elf LM fuel

Motec ECU

Motec CDI

Mercury outboard coils

WoooHooo……400 bhp here we come….and wouldn't it sound good

jesus...took that the wrong way...just jokes man, frick people need to lighten up bigtime. I spose you probably dont know what im like so i guess you could easily take what i say the wrong way.

Apologies man, i seem to have this problem alot...probably should just say nothing from now on, might keep peoples knickers from getting in a knot.

jesus...took that the wrong way...just jokes man, frick people need to lighten up bigtime. I spose you probably dont know what im like so i guess you could easily take what i say the wrong way.

Apologies man, i seem to have this problem alot...probably should just say nothing from now on, might keep peoples knickers from getting in a knot.

my apologies as well. It just seems as though everywhere I go, everyone questions why I'm building an N/A motor since turbos are much more efficient.

If that were the case, however, I would have saved the money and got an LS2 and dropped that in the Z without modifying a single thing on the engine.

But I have my plans, and I'm sticking to my guns.

Truce?

oh yes oh yes!!!! a high comp 26/30 NA.

i'd want to try and bump the 11:1 up a little more if possible (may as well :()

and be sure to have trumpets

Ideally, what i'm shooting for is a safe engine with virtually no knocking on 94 octane gas.

safest range I've heard of is near 11.5:1

so if I do some head work and manage to drive it on a nice cool day (It's Canada, not a rare thing to say the least), I might be able to get by on 11.5:1

but there will be those muggy days. damnit, if only they made hydraulic/electronically controlled headgaskets and stretchable belts that could grow extra teeth on command. :(

post-8303-1183581038_thumb.jpg

That should help with the bearing and tunnel sizes. If you work to around .002" clearance on both the mains and conrod bearings and around .004" end float you wont have issues. Unless the crankshaft needs to be ground, just polish it. The main bearing tensions are the same as an RB26 and if you're not using aftermarket rods, fit a set of ARP VG30DETT rod bolts. You will need to trim the length of them to clear the cradle. It's a good idea to fit an RB26 oil pump as well as a drive collar while you have it apart. Apart from that the bore size is 86mm standard, the same as the 26. What are you doing to get the compression up to a decent n/a ratio? You could run an RB26 piston and deck a fair bit off the head which will get you well up in the 9's, all depends how much you take off the head. If you're using an RB20/25 sump you will need to bend the little baffles at the rear to clear the conrods when they rotate.

I hope this helps

Cheers,

Greg.

Hi Greg,

Thank you, greatly, for the king bearing clearance chart. I've attached what ACL Bearings provides. Would it make more sense to use this chart, as I'll be (most likely) buying ACL goodies?

What I've got already is:

Spool Rod set, HKS 264 8.7mm cams on In- and Ex-. HKS RB26 Cam Gears, and will probably be having the machinist do some headwork. Hopefully he can give me a set of his part moulds if he uses some so that I can compare the stock to the reground ports to see what he's done.

I don't think I'll be doing any work to the valve train for now, as budget is a tad limited (budgeting some cash for the car itself). I may upgrade to stiffer valve springs and higher lift cams, provided my piston choice allows me to set that up for the future.

As for pistons, I might as well just get fully custom slugs. No point in machining a set of shelf pistons and weakening ring lands and crown material. I'd rather just play the safe bet and put some more money towards some properly made goodies.

Chances are I'll be using a thin MLS Gasket. perhaps Cometic, maybe Tomei or Greddy if the price is comparable. I would go ACL as well, but they dont make 1.0 mm gaskets, so I'll have to find them elsewhere.

I've got the crank collar as well, and I'll order the other parts once I've purchased the pistons (was gonna buy the running gear just now, but I figured i'd buy the internal goodies first).

Hopefully with some good advice and my documentation, more people will feel comfortable trying new things with their expensive engines because they're curious to know what results they can get, which is why i'm doing this.

and besides, If i wanted to make a lot more power down the road, all i'd have to do is get some more new pistons and just add a huge snail on the end of my exhaust :(

post-29116-1183606197_thumb.jpg

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