200rwkw N/a Rb, Whats Required?

[rb26zed]

I am looking at building a serious N/A RB for Improved Production racing.

Must be N/A, under 3L, Straight, 6 cylinders and Nissan.

L series and RB are the only 2 that fit these and as the L series is getting a little long in the tooth I think the RB would be the better option. The L series has been proven over many years but it has also been developed to its limit. I think with some effort the RB should be capable of better results.

The goal is 200rwkw.

I expect that this will obviously cost a fair bit and require a lot of work. I want some opinions on what would be required to get there if it can be done.

I have seen a few N/A RB's get around 150 - 164rwkw on these forums so I think it should be possible. I am not after opinions on turbos, v6's, rotary's, Toyotas or anything else. Just simply what is required to get an N/A RB to 200rwkw.

I do not want to buy a ready done car as this simply does not interest me. I enjoy the design and build as much if not more than the racing itself.

Must be below 3L. Must be a straight Nissan 6. Must be N/A. Must run on 102ron fuel as per CAMS rules.

I would also like opinions on the question of Revs vs Displacement.

Option 1. Rb30 bottom end Rb26 head = 3L.

Option 2. Rb30 block Rb26 crank Rb26 head = 2.7L

Option 3. Rb30 block Rb20 crank Rb26 head = 2.6L

2 &3 have superior rod stroke ratios and in theory should rev higher, but will the cubes of the 3L win out.

I am collecting the parts for the build over the coming months. Obviously I will speak to a few engine builders before starting but would like to gather some opinions and knowledge from here 1st.

[Deano 1]

wow the main thing required here is goin to be $$$$ but will be very interesting to see how it turns out....

good luck mate, keep us posted

its goin to sound Insane

[PM-R33]

Very good head design will be the key and the bottom end should be built for very high comp. Given that the fuel you can use, that shouldn't be to much of a concern.

[WHITER33GTS-T]

Im sure if money isnt a problem a 26/30 would be the go. Make use of the extra cubes and I would have thought 200rwkw would be a easy goal. Half grout fill the block so it doesnt flex and dial up the revs.

[thatr33kid]

swweet

[PM-R33]

Nice way to get 10 posts

[Just_Rb]

rb26 long motor convert to n/a with custom tuned length exhaust mani, itb's, cams etc. should get you your power goal, has been done numerous times in japan, do a search on google, would probably be the most reliable option and simplest to complete.

[Pal]

swweet

warning handed out. if you have no useful information for the OP, please refrain from posting

[rorz]

I'd be SERIOUSLY interested in watching/hearing a video of a NA RB with 200rwkw. Good luck with it mate, make sure you keep us posted!

[TurboDoseBro]

Since you're quite new i suggest reading and doing everything in the 'how to get more power out of NA' thread and then add to it lol.

Edited August 25, 2010 by TyresBro

[zebra]

As I said in the thread that dissapeared, I would be concentrating on mid range torque rather than a peak power number, go the 26/30 add ITB's and cams, compression around 11:1 and rev it as hard as the valve train/bottom end will allow, dont worry about the final peak power number on a dyno....it will mean sweet FA on track if you get dusted up down QRs main strait by a 1600cc corrolla because your car doesnt start making power untill 6000 rpm and is all over by 7500.

then spend the money on some MCAs and big bastard brakes and you will be faster with 150rwkws and an excellent handling/stopping car over a car that you have spent squillings on to get 200rwks and have shithouse brakes/suspension

Plus an RB making an easyish 150-170rwks will be a shit load more reliable than one spinning to 9000+ and making 200.

Im not sure how much circuit expirence you have but there is more to a circuit car than a dyno number.

[rb26zed]

Actually tyresbro I'm not new, I've been a member since Jan '07, and browsed here long before that. Post counts don't mean much.And yes I have read that thread numerous times but it doesn't come to any real conclusions.

Zebra I may be somewhat new to competitive motorsport but that does not make me a newb. I do understand how a curcuit car works. Suspension, brakes etc are under control. What I want to know is if my chosen car and engine, each of which dictate the other in improved prod, are up to the task of putting competitive power down. I'm trying to find this out now before I outlay money on a base car and engine.

What I would like is people who have experience/knowledge on different aspects of what is needed to share thier opinions on cost and power.

Here is a quote from sydneykid a few years ago. Share what you know/think about this combo.

"One day I will put one of these into a 240/260Z

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"

Now it has to be under 3L so ignore the 3.1L bit. What about the extra revs of a 2.7L setup, would the extra 300cc of the 3L trump it?

[zebra]

That sounds like a good combo, but the 13.5:1 comp may be a might much for a circuit car that needs to run hard for lap after lap on petroleum, 13:1 would be fine for alchohol or E85 though, not sure if IPRA QLD allows E85 or not.

and could prob go bigger on the cams for an atmo engine, get something made to suit a non turbo.

Oh and forget the N1 pump, spend the $$$ on an external pump at a minimum unless you wanna rebuild it after every event

Dry sump would be even better.

[TurboDoseBro]

Well then, suggestions of my own:

Reduce unsprung weight

- Lightweight pulleys

- Lightweight flywheel

- Lightweight clutch

- Balanced crankshaft

- Lightweight wheels

- Lightweight tyres

- CF driveshaft

- Lightweight drive shafts

- Lightweight cams

- Lightweight brakes

Why? because not only will it lighten your car up and increase acceleration, it works well for dyno figures as you are using more % of the raw combustions from the engine. Should be coupled with decent power mods. By the way this is just a theory lol

Edited August 25, 2010 by TyresBro

[rb26zed]

Thanks fellas, thats the kind of stuff I'm after.

I think 102ron fuel is the max allowed from what I've found so far. What comp do you think you could run on that.

What are the biggest practical cams you've seen on other NA engines. I've seen 312' on a 4age I think.

[PM-R33]

- Lightweight cams

Lol that's a new one

[zebra]

Thanks fellas, thats the kind of stuff I'm after.

I think 102ron fuel is the max allowed from what I've found so far. What comp do you think you could run on that.

What are the biggest practical cams you've seen on other NA engines. I've seen 312' on a 4age I think.

290deg total duration would be a good starting point for an angry NA engine, would need a solid lifter conversion if you were to use a 25 head, or a bucket over shim setup for a 26 and something around 11mm lift, it would need a bit of clearancing of the head.

Best bet would be to speak to a top notch head builder about port work etc as they will really determine what cams will work and a cam grinder will want to know the flow numbers of the head at different lifts.

We can only help you so much over the internets, as im not a cam manufacturer and without seeing flow numbers of the ports its just guess work.

1 more thing - spend more money on the head than the bottom end, as that is where the power is produced.

[TurboDoseBro]

Lol that's a new one

lol I mean those cam gears.

Also don't forget lightweight wheel lug nuts LOL

[NISMØ]

Don't think a 4" Titanium Exhaust is necessary, Id'e say 3" max for an NA.

[TurboDoseBro]

If there was 2.75" i'd definately get that.

2.5" has very linear power from low to high. Gives more precise throttle adjustment/levels too. Revs faster or more responsive. Lacks the kick in power and i'm guessing max power compared to 3" by feel.

3" is pretty empty down low but is a blast at high rpm (5k and over) like VTEC just kicked in yo. Lack of back pressure makes the throttle feel weak at low RPM and not very precise. Feels like it has more top end power than 2.5".

This is from a guy who just got his cat back changed today.