What traits do different engines have?

[stevo_gj]

Hey Guys,

 

You may have noticed that I'm looking to buy a restored 260/240 Z in the very near future. Looking to spend around 14 but that will increase the longer I put it off.

 

Now here is my question: I notice many cars have had RB20s 30s 25s and others swapped out for the L series. The primary use I will have for my Z will be as a daily driver and I don't really know a great deal about the different engines that are in the Zs i'm looking at.

 

Obviously the engine won't be the deciding factor for me but I do wonder what traits certain engines are known for having?

 

I have driven an EFI L28 in a 240z but thats the extent of my engine experience.

 

Cheers

 

Steve

[gav240z]

Hey Guys,

 

You may have noticed that I'm looking to buy a restored 260/240 Z in the very near future. Looking to spend around 14 but that will increase the longer I put it off.

 

Now here is my question: I notice many cars have had RB20s 30s 25s and others swapped out for the L series. The primary use I will have for my Z will be as a daily driver and I don't really know a great deal about the different engines that are in the Zs i'm looking at.

 

Obviously the engine won't be the deciding factor for me but I do wonder what traits certain engines are known for having?

 

I have driven an EFI L28 in a 240z but thats the extent of my engine experience.

 

Cheers

 

Steve

 

Not sure what you are looking for exactly. I've never driven an Rb20, Rb25 or Rb26 powered car.

 

I have driven:

 

L24

L26

L28

L28 Turbo

L28 EFI

L31 Stroker

 

SR20

RB30 ET

 

The L24 is a punchy motor, in fact I much prefer the feel of early 240z over early 260z's with the original emission controlled carbs. The L24 revs very nicely when in good tune, but power like all L-series engines starts to drop after 5,500rpm

 

L26 (stock) is ok, but a little bland compared to stock L24.

 

l28 (stock) depends on which car its in, but its less willing to rev, but feels more torquey. EFI set up is very smooth but saps some top end power (depends on the year and intake manifold efi setup etc..).

 

L28 turbo was a carby turbo set up. It was pinging at the time so I didn't flog it hard. Not really a great experience, could be made to go fast but sounded like a vacuum cleaner. Fuel hungry.

 

L31 Stroker - Great engine loved it. Very strong and very torquey. This engine had been modified and balanced / hence loved to rev had plenty of steam, but limited at top end by SU carbs. Triples would be fantastic. (Hence reason I'm building one).

 

SR20 is a great little engine, if I didn't buy a Z, I would have got a Silvia S15 or a 180sx. Great cars and the SR20 feels really responsive and has good torque for a 4 banger. Good on fuel too.

 

Rb30 ET - Drove it in a VL chommodore . It was mated to an auto so not the best, was a fast car but I hate VL's and I hate auto's. Plenty of low down torque, fuel hungry and lots of crazy turbo noises from the wastegate. A good engine (wouldn't want an auto one in a Z though) and not as rev friendly as the L-series.

 

I think a perfect combo is the RB30 block with the 25 / 26 head if your into that kind of thing. However I tend to like smaller engines that rev really hard too and in a sports car like a Z its quite nice to be able to rev it up quickly and freely.

 

I really like the feel of the old L24 in a 240z. Something about it, its like Nissan got it just right. Then emission rules ruined everything. As a daily driver a L24 in a 240z is not too fuel hungry and seems to be pretty good. In fact many studies have failed to prove that all that emission gear they added in the 70's to carby does actually did any good. In some cases some people think that it makes their cars more fuel hungry and they get worse fuel enconomy.

 

Remember most of these cars are probably going to lack regular maintenance and as a result may not drive like you want them to.

 

a well maintained early 240z on hitachi carbs with correct ignition timing and engine is a true joy to drive. However a fuel injected later RB engine in a Z might be just the ticket you need in a daily driver.

[stevo_gj]

Wow Gav that post is very helpful thanks very much! Thats exactly the sort of information I was hoping to get, just peoples general opinions of the motors and recommendations of which would make a good daily driver but not leave me wanting for more power.

 

[sco_aus]

Animal fan Stevo? Good post.  I used to have a L28 EFI in mine and it had a nice torque feel to it.  Then when I went to RB25DET with only a few small mods it was really quick and driving around town used bugger all fuel, highway was AWESOME!! 

Now after all the mods, well RBs are known for being fuel hungry with a bit of power, so basically, if you do go RB, keep it simple like intake, exhaust and front mount, a nice 150rwkw and good fuel with fun on tap.

[stevo_gj]

Thanks Sco!

 

Yeah I do love animals hehe.

 

Very good info. I quite like the idea of a newer engine that would be better on fuel and have decent power. Gav you mentioned that the RB30 would be a good combo when combined with the 25/26 head. Were you referring to good in terms of power? There is an RB30ET turbo Z for sale in Perth that looked very nice but didn't specify the head it had.

 

Anyway I had better get back to study, this forum is an awesome procrastination tool 

 

Structures and Materials exam here I come...

 

Steve

[zedevan]

this forum is an awesome procrastination tool

 

hehe agreed!

 

its just an rb30 head, you'll find they are rb30det's to show the fact they are double overhead cam engines, and swapping the heads makes them harder (more expensive) to get through engineers certficates due to emissions

 

my l26 with 240z carbs compared to other cars i've driven has felt the closest in power to a 2.5litre outback (but alot more fun to drive ofcourse). like it has enough torque and power, but could do with more of both

[JP240z]

rb30et would be a nice motor in the zed and bolt on mods are plentiful due to the vl's. But if I were you, looking at the car as a daily driver, you would get good power and awesome fuel economy out of the rb25det. I have both an r32 and r33 skyline, and the power difference is huge, especially when boosted, but the fuel economy is similiar. So my vote would definately be with Scott and the rb25. You could also get great streetability out of a stock rb26dett, but they can get quite thirsty on fuel.

[Scando]

I think my L28ET is a great engine.  It only put out 174rwkw but due to the massive amounts of torque it produces it easily lets the lighter Z keep up with R32 skylines with 250rwkw.  Having said that I wouldn't put one in a daily driver.  Mine is very thirsty and for a daily driver the reliability of an RB would be hard to go past.  Most of the R32's I race against run around 20psi through stock bottom ends with no problems (wouldn't reccommend this for a daily though).  Only problem I've noticed with RB's is they are absolutly gutless off boost, even in the larger RB25's and RB30's.  But I think for reliability go an RB.

 

The other engine that I think would be great for a daily driver is an SR20.  They're probably not as reliable as an RB but the low down response for a 2L is awesome.  After driving a couple of GTi-R Pulsars I was left amazed at what this little engine is capable of.  They're excellent on fuel too being a 2L 4 cylinder.

 

This is all assuming you want more power than a lightly modified N/A L series is capable of.  I've had two R30 skylines (N/A L24) and they're industructable and excellent on fuel.  They love to rev and I gave them a very hard life.  One of them still made it to 550,000k's on the original engine!  But I don't think these engines are going to produce the sort of power you're looking for without turning them into a pig that has nothing until 4,000 rpm which isn't what you want for a daily.

[RBZ 260]

well i got a Rb20det in my 260z 2+2. few bolt on mods like bigger turbo exhaust and intercooler. boost is at around 12psi.  my diff is fairly short 4.4 so im not using the engine properly. though still it will keep up with a gen4 v8 commondoore from rolling start of 80kmh.

 

had few runs against wrx and of the line even the mighty wrx cant come close. also few against r32 and s15 and every time the 260z keeps its nose way in front.

 

petrol wise as its my daily car its approx 12Lper/100km  if you drive reasonably. if bit heavy footed can go over 15L.

 

RB20dets like to be reved unlike the rb25 i found bit lazy. off boost yeah bit slooow but  just build the revs up and drop the clutch and hold on 

 

i also own a l28 240z with twin su with extractors etc..... it moves fairly good but it lacks the massive turbo push at higher rpm that the 260z has. fuel dont bother asking. more like a 8L v8 LOL.

 

for a daily driver i wouldnt go past the sr20det. I owned this motor for 12 years in my s14a. still original turbo and no engine trouble what so ever. ran 1bar (15psi ) boost most of its life. destroyed 3 gearboxes, 4 clutches and 1 diff. still doesnt miss a beat. it suprised and beat cars 3 times its capacity with ease.and best of all it will give you 10l per 100km with few heavy right foots.

in a lighter 240z shell it will only be better than when its in s14.

also these are fairly easy to fit into a zed without too many mods. which is good if you want to return it to original specs later down the track.

 

when time come for my 240 to get a facelift i think the sr20det is going to reside in its engine bay.

 

[JP240z]

Oh yeh my bad I forgot about the sr20.. probs a better option.

[stevo_gj]

Well, now that I have my Z with its original L26 I'm considering what I'll do with the cash I am going to make at the mines at the end of the year. I am pretty much sold on the idea of the SR20 conversion, and have heard a few people say it would cost around 5-6 for the conversion. Does that amount include the cost of the engine itself?

 

I will most likely not be able to do much of the fabricating of engine mounts myself. Rbz 260 you have been posting in almost every thread in this section of the forums about this conversion and I was wondering now that you have me sold on the conversion what other advice you can give about it? I was trying to read your post where you detailed the steps for the RB25 and Sr20 conversions in one go but I got confused 

 

I have read that having a small engine like the SR20 mounted close to the firewall gives something akin to a mid engine car, but I don't know why this is good. Is it the balance factor?

 

Cheers

 

Steve

[tbscobraZ]

Center of gravity, balance ect...

[Scando]

Yep, it's all about the balance of weight front to rear.  Z's are fairly well balanced out of the factory but the more weight you can shift towards the back the better.

 

If you can't do any of the work for the engine conversion yourself then I'd say the 5-6K for the conversion (not including the cost of the engine) would be on the cheaper end of the price scale.  There's a lot of work in an engine conversion and labor is very expensive these days.

[stevo_gj]

Thanks for the tip Scando.

 

Probably a stupid question, and I think the answer is no, but will an L series gearbox attach to an SR20? I ask because the gearbox I am mounting in my Z has been rebuilt and it would be a shame to change it so soon if I decided to swap.

 

I guess the other question is, if I went along the SR20DET turbo road will I have to upgrade the drivetrain to handle the power it would output ? 

 

Steve

[C.A.R.]

You 'can' swap a SR bell-housing onto a Zed box with a couple of small mods to the BH.

I really wouldn't bother though - SR boxes are plentiful & cheap enough.

Tuck your current manual box away after the conversion or sell it to fund the SR conversion.

 

FWIW, the early 240Z box is called a 71A (has the output flange at the back of the box).

Late model 240Z & 260Z is called a 71B box,

And the R31 skyline, R32 GTST Skyline & S13 boxes are all called 71C's.

They are all just evolutions of the same box.

 

[RBZ 260]

I will most likely not be able to do much of the fabricating of engine mounts myself. Rbz 260 you have been posting in almost every thread in this section of the forums about this conversion and I was wondering now that you have me sold on the conversion what other advice you can give about it? I was trying to read your post where you detailed the steps for the RB25 and Sr20 conversions in one go but I got confused 

 

I have read that having a small engine like the SR20 mounted close to the firewall gives something akin to a mid engine car, but I don't know why this is good. Is it the balance factor?

 

Cheers

 

Steve

 

Steve,

 

why is it better to have engien closer to firewall its been answered above.

 

As for gbox just use the Sr20det one. also as said above plenty around and reasonably priced. also dont feel like the truck box of the original Z car. plus prob bit stronger.

 

I have killed 3 gboxes in my s14 200sx. with few mods and decent clutch and a rough left and right foot and quick gear changes destroys them quickly. but if u dont flat change gearbox should last a fair bit.

 

as for conversion. you realy need to shop around. here are some tips to get a good deal for both engine and labour.

 

1. DONT EVER EVER come across as a novice. so read about as much as you can learn about correct terminology ask smart questions.question y this and y that but not everything otherwise they will figure you as a novice and spin you lot of crap. you dont need at least 50% of the crap they try to sell you.

 

2. be polite and friendly.if they busy and not in good mood just ask a simple question can it be done and rough cost. than walk away.prob even better is to call them prior. dont give your real name.

 

3. when buying front cuts or whatever. u got to options to buy the engines. "A" from importer or "B" damaged car auctions.

 

from importer it pays to visit them regularly and get to know them. if u see something small that you may need buy t. dont haggle much. work out when times are worse for them. expecialy when left over stock or stock that was sitting for a while. also when they need to recieve a new container they need money. any reasonable offer wont be refused.just have to be there at the right time and right place with money. i got my rb20det front cut for $1300 prices elsewhere at that time were 2000 to 3000.

 

at auction make sure the parts u need are not damaged. but you need to take the whole car home.so make sure you got room.

 

4. to save lot of $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ dont be afraid to do things yourself. if you can work out how to use a mobile fone or a pc you can work on a car too. use stock stuff forget spending big money on aftermarket this and that. get it runing right stock. reasons to save money. after you can mod it and make it faster.  also if you can plug in a dvd player to the tv you can do the wiring on the nissan engine (if transfering stuff from front cut to the z chasis. i could easly talk you through the wiring).

 

5. hardest thhing would be getting the engine brackts made up. again if u can use a ruler you can get the basic bracekt orginised by a accrediter welder.

 

6. again where ever you go be polite make sure you know what you talking about. dont piss ppl off thank them for ther time and you think about what you just found out.

 

do lot of walking and ringing around. talking on forums etc.... get as much info as you can so you stop them ripping you off...

 

i can give you more info on how to save money when buying

 

to tell you the truth if you were in adelaide i could do a turn key job quite easily for about half the money.

 

anyway....

 

any more questions im here to help.

 

 

 

 

 

 

 

 

 

 

 

[stevo_gj]

Cheers lurch, that answers several of my questions 

 

rbz260 those tips are great! I will definitely pick your brain on the subject before I make any purchases. You have given me a good place to start.

 

Thanks again,

 

Steve

 

 

[gav240z]

Some more tips on the topic of engine conversions.

 

I know of far too many people who have shopped for the cheapest quote and ended up disappointed by shoddy workmanship.

 

If I was going to pay someone to work on my Z I would do the following:

 

1.) Speak to people who have had conversions done in the past. If possible the same swap and their experiences with the person who they got to do it.

 

2.) Find out what your local laws say about the conversion. Speak to your local road authority. Ask the engineers who inspect cars what would need to be done. Take all this into account before speaking to a shop. Get an idea of what you think it will cost, perhaps even ask the road authority.

 

3.) See if the shop getting it done will guarantee their work and ensure it will pass engineering.

 

4.) As said above when speaking to these people remember they have a business to run. Taking up loads of their time without spending cash is a good way to ensure you rub them the wrong way. Having said that, anyone who isn't willing to give you 10 mins is probably going to dick you around.

 

5.) I myself will never choose the lowest quote. I'd rather spend a $1000 or so more on a conversion if I know it will go smoothly and no shortcuts will be used. I'll also always look for people who have done a conversion before or have experience in this field. Ideally someone who knows Z's backwards but doesn't have to be. Just make sure they have happy customers. Car magazines often name workshops that carried out work, so that can be a good start.

 

Steve you have a nice stock looking Z. I suggest you enjoy it as is for a little while. Save some cash on the side, I would personally put away $10k before doing an engine conversion. This will allow you to do suspension and brakes (brakes probably most important to me).

 

Making your car handle and stop quicker is one of the best ways to make it faster on a track. You may also find that some minor mods to the old L-series really transform the car. I know that a mild cam some early 240z SU's and remapping the electronic dizzy really makes a difference.

[RBZ 260]

Gav has some good points too.

 

pretty much what he said i agree besides few things like PAYING more and TRUSTING!

 

there are people out there that do lot better jobs than so called respected workshops.

 

like he said check their work. have a look etc.....

 

before any of that you start. ask for rules and regulations. than start shoping around. some engineering can cost lot of money. but i think QLD is fairly good with their modding allowance.

 

ive been around these so called proffesionals for years. and only person you can trust on work is yourself. sorry guys i lost all faith in proffesionalism. its all about making money the quick and easy way. the ones that do good work they usualy dont have bussiness and work from home.  again check their work it will speak for them.

 

 

ive  started writing a project on my car in project journal section of this forum. bit long and boring but heaps of info.have a read and you see the steps i went through and prices i paid.

 

so far i havent been burnt by any of the guys i delt with. if something was wrong it was fixed without an issue.

 

you just have to get to know the right people in the right places.