C110: RB20 or L28?

[NZeder]

Re the NAPS intake thing - if I was going to keep this I was going to install a 65mm TB to replace the twin butterfly setup and remove/weld up the EGR. There are a few non EGR intakes here in NZ (NZ new cars only as the JDM have the EGR) as we did not have any polution control requirements until just recently (not sure if we have any standards at all just that all new cars now have it fitted standard not sure if this is a local legal requirement or just because that is the way they come - anyone else from NZ confirm?)

[440k]

Lachlan - If I were you, I'd stick to a warm L28. There's a guy in Brisbane who builds lots of hi-po L28's, and he's a darn sight cheaper than any of your big "tuning houses". This guy mainly builds for the rally / race crowd, so builds stuff that works (without the fancy stickers to go on the side of your car)

Harry (the guy I bought my car from) knows this fellow, and says he makes excellent cheap horsepower.

I tend to agree with many of the other sentiments. Whatever you choose, it HAS to be an L6, and HAS to have 6 throttles (whether that's by way of triple side draft carbeis, or 6 EFI is up to you). The L series is bullet proof - for a sweet driveers engine, you can't go past the crisp throttle response of a well sorted N/A

Turbos are nice for the mid range rush, but you can't beat the feel of an N/A (my personal opinion)

I also agree about the "bastardisation" of the 240K. Hypocritical coming from me, I know (pushrod boat anchor nestled between the front guards in my car) but that's more of a "let's see what we can achieve with wha's already there". When I want to get serious with it, I'll probably go back to the L28.

[240K&Beyond]

Potential Hijack Alert: The L28 R

No John (Blue Leaf), It's not a typo, It was a very special engine that came out of a 2 door R30 vintage Skyline that was personally imported from South Africa. It was around 1990 so my memory fades a bit. I cannot remember if the engine number was L28XXXR or L28RXXX. Where XXX were the numbers.

I didn't think anything of it when I bought it 2nd hand off the guy that imported it. I also bought an L20A turbo motor and a 2nd hand T3 Nissan Racing Turbo. The plan was to put it all together and teach myself about EFI systems.

The guy I bought it of "Simon G" had just started a garage company under his parent's house called "NisPro Performance" which is now quite well known in Melbourne and Oz for making some pretty silly engines. I think he was the 1st to pull 1000 HP out of a RB30 and for that matter the Ford BA4.0T engine.

Anyway, he said that the motor used to beat allot of V8's around in it's stock form in the 2 door coupe. I took it with a grain of salt, bought the bits and went home to construct my new 240K heart.

At that time intercoolers were at least $1500 so it was not an option. Knowing this I went down the "Low Pressure" Turbo, "High Pressure" Cylinder path because at lower boost pressures, the air into the engine is cooler and does not need an intercooler.

The advantage to Low/High is that you get quicker spool up times, better low down grunt (engine rev wise) and neck snapping acceleration. However, the disadvantages follow that: You need a very strong bottom end of the motor, there is more potential to achieve predetonation (pinging) and a few other nasties. Consequently, Most car manufacturers go down the High/Low path using an intercooler as the result is more driveable, safer, and there is less risk to the engine. It's probably cheaper in the long run too.

So, keeping all that in mind I wanted to reduce any air restriction both inward and outward of the motor. Off went the head and down to a head specialist to port, polish and put bigger valves in. I was confused when I got the call from the specialist asking what I wanted him to do as the head already had the biggest valves in it he had ever seen. And the funny part was they were all stamped “Nissan” WTF ! He tested the valve springs and said they were good for around 7000 RPM and were as good as what he was going to put in. So I got the port polishing done as he said he could not grind them out anymore than they were already quite large.

I jumped on the phone to Nissan’s Head Office and asked if I could get the specifications and possibly a manual for my L28R engine. This was when it got interesting; They said they have never heard of such a beastie. I asked them to follow it up further. Two months past when they returned with an answer, well actually, it was a question: Where Did You Get This Motor From? I explained the history to which there was a long silence at the other end.

The Engineer at Nissan Australia’s Head Office explained that this engine was in fact a racing motor and that’s what the extra R in it’s number meant. It was a limited release and should not be in the country. Yes, they were release in South Africa as there laws were more relaxed.

Apparently, the engine had the larger spec’d head, a fully balanced crank, larger bearings and flat top pistons producing 10.5:1 compression. Needless to say, I got off the phone and jumped in the air for joy.

I quickly put the head back on the motor using two head gaskets to lower the compression down to 10:1 and bolted the turbo and all its bits on. Spent two days tracing out the EFI wiring loom and wired it into the car.

The first time I took it out on the road after the exhaust was installed, I was happy with the acceleration as it seemed a completely different world to the original carburetted 2.4 litre six. However, it started pinging at 3500 RPM and ran out of fuel at 4000 RPM.

Needless to say, my learning curve had only just begun and there were plenty more tricks to learn in building an EFI Turbo Motor. But I have been crapping on for ages now, if you like, I can explain some of the tricks later.

Just out of interest, has anyone else heard of, or experienced a L28R? I would like to know more about there origins, were they were release as Nissan Australia really didn’t want to talk about it.

Miles (Sakijo) in your travels, has anyone ever mention them?

[Mr Camouflage]

not sure how much truth there is in that! i would have thought that with a more modern cylinder head that the chances of getting better economy would increase if the tuning is spot on.

of course economy goes out the window if the right foot is heavy on the pedal...

I think he meant loosing economy compared to a RB20 if you built a RB30

[g72s20]

...AArr Good on ya Bruce! you've got me well and truly hooked on this L28R thing. Just where is that engine now, hmmmm?

I'm off to check out South African Datsun sites now!!:stupid:

[sakijo]

Never heard of an L28R. Another interesting topic. Japanese might have something on it. Suggest moving this to a new thread before we totally hijack it.

[240K&Beyond]

I have opened up a new thread.

Sorry Jim, I have already been there without result. Google SA is a very hard thing to deal with.

Unfortunately my old 240K coupe died with the engine in it. A bloke "T-Boned" me which pushed me off the road into the back of a parked 10 tonne truck.

I recovered the engine from the wreck, but never got it running again. It was eventually sold with a 240Z I had at the time. I lost track of it then.

[240K&Beyond]

Lachlin, back to your original question and my comment, If you plan to go down the L28 path. You should look for an 81-83 280ZX manual car. These have the F54 Block and the P79 head. Have a look at the following:

http://www.geocities.com/zgarage2001/engine.html

[NZeder]

Lachlan, re the F54 thing - there are two stories out there, some say the F54 is the best block to use as this is the later type etc, well I have both F54's and N42's and the research I have done does not show the F54 as a better block. Most of this F54 stuff comes from the US where they got the L28 before we (as in AUS/NZ and JDM) did. I believe there might be two types of N42 out there, the first one, ie the ones used in the 280z = US spec, and then the later units used in the 280zx before the F54. If you are planning to stick with a stock bore size then the F54 is a good choice. If however you want to build a big bore L28 use the later N42 block as these too are a siamesed cylindered block but the water galleries are not as large = bore bigger (I believe others have done sonic testing on both blocks and can confirm that the N42 have more meat for over boring). I believe the water galleries were changed for extra cooling in turbo applications (given the F54 was the turbo block also)

I have also found that most of the Japanese build 3.0 and 3.1 use the N42 blocks so this might also suggest they are better suited to this application. I once found a Japanese site that would build a 3.0 on a F54 but stated that block filling was required (got lost in the translation but I think this was again talking about the water galleries and the lack of cylinder wall after a 3mm over bore) also escort (a piston make in Japan see http://www.escort-jp.com/) only shows a 88mm piston for the F54 block....hmm all this starts to tell me that the F54 is not a good as it is cracked up to be (well this is my research and opinion)

So while other are hunting down F54's go an pick up a few N42 for cheap while you can if the L28 is the path you want to go.

Just my 2c on the F54/N42 thing - again sorry for the slight hi-jack.

Lachlan if money was not an issue I would track down a S20 and build the almost perfect GT-R replica however given the thread question we can assume that will not happen (S20 do come up on yahoo.co.jp from time to time but more $$ than you and I would want to spend unless we won lotto but then we would just purchase a real KPGC110 and be done with it ) and as you know there are a lot of JDM GT-X with the L28 treatment and a few with the RB20/25 and triple carbs. Re the RB2xDE (not the DET's) from what I have been told by an engine builder locally you can't get a lot more over the standard output without spending a truck load of $$ which does not justify the gains. This engine builder said if you want power from a RB it must be a DET not a DE. So it comes down to this - what do YOU want? Lots of power? a DOHC? Turbo or N/A. So if you want DOHC then you have just one (Nissan that is) in-line 6 and that is the RB series. If you want power then how much $$ have you got and what is the best bang for your buck (don't forget any engineering that might be required if repower is the choice). Then if talking N/A what type old school carbs or EFI.

You have a lot of choices - I know I have been though them all myself.

Whatever you do I am sure you will be happy and the quality will be great just like the work you have done on your car todate.

[440k]

I'm on the verge of getting a full-time job

Congratulations, mate! Is it a definite, or still "in the pipeline"?

Hope all goes well. If you need somewhere to store the K, I'm sure there are plenty here who'd help you out:nervous:

[khughes]

woops, i missed this thread.. and i guess i should put in my opionion, i have to admit first up that i have taken possibly the most windy (and most probably costly) path to my goals, and i still have quite a way to go

i wish i was a lot more logical in hindsight, but at the time i knew little about the engines involved (not much has changed and the whole modified car process

to summarise i guess:

• L28: sound is #1 simply awesome! i chose not to upgrade to this probably a little out of ignorance, and because i know nothing about carb'd engines
  
• SR20: close! it's a nissan, but no skyline heritage!
  
• RB20 (NICS): tried it... i came to the conclusion that if i was going through the pain of the conversion, i may as well do it properly
  
• RB25: skyline heratige, 6 cylinders!, noises in all the right places, plenty of power, similar weight to the L24, plenty of parts available
  
• RB26: too $$$... spending 2x on the RB25 was obviously a better move
  

Why did i go down the RB25DET path? well... the answer is pretty simple... i owned an R33 GT-R... and they are very very addictive!

The skyline bug bit me so much so that i decided to build up a 240K into a GT-R replica as they were extremely rare and nobody in the SAU community (life and blood of Aussie skyline enthusiasts!) had really gone down the classic skyline path (well... before the R31) except a few rare cases.

I couldn't justify $6.5K for an RB26DETT, and that was without a gearbox! (little did i realise, it probably would have been much cheaper for me to go down this route!) and meanwhile there was a HUGE thread on SAU about the RB30/25 hybrid, and that captured my imagination! An RB25DET +box was around $3k, and aftermarket parts are a LOT cheaper (except injectors!). The thought of an SR20 just didn't site well with me.. sure they are a great motor, but it is a 4 cylinder (phhht ;D) and if i was replacing the motor, i may as well replace it with a genuine skyline heart!

well.. my plans deviated here and there as the plot thickened, originally i got my hands on an R33 RB25DE and a bought a $100 RB30E block out of an R31 skyline.. ripped them all apart began collecting the bits for the hybrid conversion (it would have been so much easier and cheaper buying a half cut).... to cut a long story short, i decided to fast track my hybrid plans, set them on the backburner and get the car running with an engine. so i bought an RB20DET (NICS) and gearbox out of an imported R31 race car from ebay for $750

The NICS engine was in pretty good shape, and importantly had all the bits that i didn't have for the hybrid.. wiring looms, computer, small intercooler, AFM's, turbo etc.. and because the mounts were the same and the engine is of a similar size, so that would have been an easier transition.. so i started out up that lane... it didn't take long for me to realise though it was a bad move, as the gearbox was smaller, and the engine would never put out any power that i would be happy with (even until the hybrid monster was ready), so i took an oportunity to sell it again for the price i paid for it (minus the costs of refreshing the oils, belts, plugs and powdercoating the cam covers).

At this stage, i sort of came to the realisation that although common, the RB30 conversion would cause hassles for me down the track with engineering (and there is so much other stuff that needs to get through that i decided not to chance it, maybe one day i will bolt up the rb30 bottom). so I then decided to buy a full RB25DET + gearbox, it would give me most of what i would, it would be a good basis for as much power as i would want to put out (current goal is 300KW at the wheels), it was a modern engine with EFI (i sort of understand that!) and i could apply most of my knowledge and research from the RB26 on my GT-R to the RB25...

so apart from a Greddy intake to keep the engine low in the engine bay and a few "in preperation" upgrades (like greddy top mount fuel rail, nismo 700cc GT-R injectors, bosch 044 and R32 GTR fuel pumps, ATI harmonic balancers, RB26 water pump, Apexi ECU) i am trying to keep the engine fairly intact and concentrate on getting the engine in the car, down the track it will end up getting a bigger turbo, cam's, cam wheels etc... all stuff that can be used on the RB30

so my recommendation is to pick a power band that you want to achieve and how much you are willing to spend... be reasonable though.. the more power you have the more you need to upgrade, and of course the more traction you will loose.

pick one engine that you can upgrade later, and if it is an RB, get a half cut.. you will make life a lot easier when your trying to hook up all the emissions gear, and in the long run you will save money! RB25 and RB20 half cuts are getting very cheap now.. you can usually get half cuts for the price i would have payed for the engine alone 1-2 years ago.

an L28 will certainly be cheaper, no need to get mounts or driveshafts made up, no need to engineer the car (saving $500+) etc., and still some room for improvements, but not enough power to really affect handling or drivetrain

for a turbo RB you would certainly need to look into upgrade brakes, diff, cv halfshafts etc.. otherwise the car will be forever braking things

I can certainly see the advantages of the L28 having been in Jim's C10.. but i can guarantee you that an RB powerd C110 on full throttle will also be something very VERY special!

sorry for rambling a little...

[240K&Beyond]

When I turbo'd my L28, I broke 1 clutch, 1 gearbox, 3 half axles before the cv conversion, rear drums continuously, several demerit points and a boot load of tyres.

Hell Kent, I didn't realise you have just about fitted everything into a K.

Thanks for the input.