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mtopxsecret6

3.1l rebello engine

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After seeing the you tube video sushi put up.. ive been thinking if i should mod my engine or not. Also, the devil z has a 3.1l tripple carb twin turbs setup. Of course.. its a japanese cartoon, so not real as such. But, what is involved in building these engines? Ie,  start with an l28 stroke bore etc.. or maybe start with an rb30 with l28 head bore stroke etc.. Basically, is it feasible? If i were to mod mine, i think i would go down either of those paths.

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Stroker = pointless, unless your going to spend 12k+ on a 'proper' L31 build.

A well built L28 will eat a budget stroker any day of the week...

Just my opinion - I'm quite happy to be proven wrong.

 

BTW, this has been covered before.

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heya mtop, I would say the australian equivalent would be getting an engine built from Stewart Wilkins Motorsport http://www.swmotorsport.com/index.html?lmd=39067.093299. These guys have been working on L series engines for a long time and know what they are doing (imho, not that I have personally had any work done there). I'm considering getting my stroker engine built there but I'm not sure yet. You could find a really good builder locally but it's just trying to find someone who has been proven to be good and who has a history with the L series like Stewart Wilkins can be quite hard. Some of the guys in the QLD zcar club could probably help out with some recommendations.

 

Check out this link for good info on heads/block combinations and interchangeable/ideal parts between the L series to get the most out of your engine cheaply... http://datsunzgarage.com/engine/

 

You can work the l series engine fairly easily and get a pretty decent amount of fun out of it. You can start with porting and polishing, getting a slightly more agressive cam and balancing all of the rotating parts so the engine can spin (rev) more easily. Definitely get the round top su's and then look at things like electronic ignition from a 280zx. And then it's all about tuning the carbies, this is really make or break.

 

Boring the block out will give you the different litre engines (displacement). The '3.1litre' engines are usually engines bored to 89mm using a diesel maxima crank  (stroker crank) that increases the stroke length from around 79mm on a standard l28 to about 83mm (using l24 rods). This gives you about 3.098 litres which people just round up to a '3.1litre'. You end up with a lot of bottem end torque and a fairly flat torque curve. You can go for a 90mm bore which gives you 3.168 litres but the problem is that you are making the walls on the block very thin and nearing water passages and decreasing the rigity of the block causing it to flex more. If you are going to be boring and engine out even to 89mm you should have the block sonically tested for thickness to make sure you don't run into any troubles (usually the f54 block is ideal). Usually you would improve the carbies at this point to get more air and fuel into your bigger engine. Obvious choices are tripple webbers, dellortos, mikuni and solex carbs. The most important part of building a 'proper' stroker engine is balancing everything that you can as the rotating mass is going to be under more stress and you might end up breaking a crank etc. When you add up the cost of sourcing the crank and rods, balancing everything, triple carbs and general machine work plus all the little bits and pieces your are looking at an absolute minimum of $5000 if you are lucky. I'm budgeting about $10000-12000 for my stroker but my crankshaft and rods just arrove about $600 under budget and I'm going to do as much work myself (including some balancing) so I'm a little bit ahead atm.

 

You can always turbo the car which is generally considered good bang for your buck as I'm sure you are aware. I'm a bit anti turbo (I have no logical reasoning for this, my arguments may include reliability, maintainence and turbo lag and the whole nostalgic thing with the old carbied engine but everyone can argue for and against these points). I appreciate a nice turbo setup and I wouldn;t kick one out of the garage for farting but I'm happy with my stroker choice (again I know it's not logical).

 

And then there's always engine conversions... but that could go on.

 

I have been researching strokers for a while, but I'm not that mechanically minded and most of my info is just parroted from what I've read/seen so I'm sure people will poke holes in some of what I have said. If you have any questions feel free to pm, I'll pull out some old links I have and give you a detailed parts list or we could organise another meet sometime soon.

 

In short, don't let people put you off a stroker, just realise that you could probably get more more power for a lot less going another route. It's just not practical but... the torque!! :D

 

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agree with the above. A stroker crank is not good $ value for the gain in nominal Kw.

There are wiser means to spend your dollar on engine hardware.

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thanks sushi.. thats the type of info im looking for. I'd like to keep it atmo myself personally, but you cant beat a good kick from a monster turbo either. Ill research those sites you have provided. Thanks.

 

Ok, maybe i should clarify, there seems to be a few who are a little short on my idea. It will be a full build, which would also include the stroking. Of course a straight stroke and no ancillaries would gain small performance.. if anything lose some performance.

so we all on the same train now?

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I'm taking the train south. This is all too confusing to me...

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thanks sushi.. thats the type of info im looking for. I'd like to keep it atmo myself personally, but you cant beat a good kick from a monster turbo either. Ill research those sites you have provided. Thanks.

 

Ok, maybe i should clarify, there seems to be a few who are a little short on my idea. It will be a full build, which would also include the stroking. Of course a straight stroke and no ancillaries would gain small performance.. if anything lose some performance.

so we all on the same train now?

 

In other words no expense will be spared and you would be taking the 'proper' build option as Lurch first mentioned?

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there is no budget.. all i want to know is.. what needs to be done for a fully built 3.1 engine. thats pretty simple i think.

what would be the best setup.

i'll pm sushi, he understands what im asking.

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The only think I don't agree on is the choice of the F54 block. These blocks in Japan are never or really used for 89mm bores and most only take a F54 out to 88mm and never at 90mm on a F54 unless some JBWeld is used in the block.

 

I have build/owned 2 x 90mm bore L28 engines one with a LD28 crank aka 3.2l the other with a L28 crank aka 3.0l both were built using N42 blocks as the F54 I had was not up to the 90mm bore (this ties in with what I have been told from a contact in Japan who said don't use a F54 for large bore builds)

 

There is a thread on hybrids that talk about the differences between the F54 and N42 some of the info on there is incorrect and some is correct. ie that statement that the F54 is siamesed bore and the N42 is not, is incorrect. The N42 is also siamesed bore - this is covered in the thread.

 

Most use the F54 as it is a new block = usually less km's ie from a later model car etc. However I don't go for the F54 on a  NA setup, I would go N42 anytime over a F54. For turbo that is a different story. The F54 was designed as the turbo block and has better cooling for the extra heat that the turbo setups create. Also if you go Turbo you don't need the bore size to make the power like in a NA setup so upto 88mm is fine but I would stick with 87mm or 87.5mm max and turbo if that is what you want to do. Then you could still stroke the F54 with the LD28 and a turbo I just would not go for a 3.1 on the F54 or N42 with a turbo as the wall will flex to much (unless you do the JBWeld trick)

 

There is also N42's and N42's ;) you can tell them apart and I am sure you guys in Oz will have a hard time finding the N42's that you really want for the 90 90.5mm bores (as they are not very common at all). There are some N42's with a much higher nickel content and these are the ones you want for a large bore = stronger walls

 

I guess the sad thing is that most don't know the difference and some of these high nickel N42's might have just been thrown away over the years.

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I'm actually using an n42 for my build :) I remember reading about the high nickel content blocks. How do you tell the difference? Is there an easy way? I suppose I'll look up that thread in hybrid.

 

Quick thread hijack, nzeder did you see my thread I posted? My crank and rods were delivered yesterday :D Thanks so much for all your help.

 

Basically mtop, the misconception is that people think the stroker crank  = horsepower when really the stroker crank just changes the characteristics of the engine (more torque, especially on the bottom end). The rest of the work you do to a stroker engine is what you would do to a non stroked engine to get more hp anyway, it's just that in the case of a stroker it needs to be done to prevent failure. Now I'm sure you have it drilled into your head what a stroker is. Over the next week I'll pm you the details on what you need to actually do it (well as much as I know).

 

I wouldn't mind collating all of the info I have into a simple (well as simple as it can be) document for viczcar. Maybe Nzeder could help out with all of his experience??? :D

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One thing that was mentioned breifly was the induction side. I remember in the NDSOC a few years back a member had a 240Z with a stroker but was only running upgraded 240 carbs.. The thing was so choked it would'nt rev over 5500 rpm. Had great torque down low but when the revs picked up, it just fell right off. You would at least need 45-48mm Webers or even better, 45 ITB's (which are an equiv to 48 Webers but more driveable) It all depends what you want to do with it..club events or the red light drags.

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I had 47mm OER on my 3.2l these replaced the Weber 48's that came with the car/engine. The weber 48's I had were not the SP version so odd ball 48's that are not that good.

 

If the head is done right then even at 3.0l 45's are too small - and the same could be said for 2.9l it is just maths, after all the ICE is just a big air pump. Air/Fuel in - bang - Air/Gases out.

 

Any performance engine is all about getting the balance right. I am not an engine guy I work in IT (which is why my website is sh!t much like the panelbeater with a crap car etc) but engines are not IT = different = hobby :D so I use good people were fit and I have a good head guy (helps that I had an old head to give him to cut up so he could improve his own L6 knowledge) Nissan did a good job on the heads of the L6 engine - yet they still have their limitations and errors per-say. So it is a matter of getting the balance right so you get the best gain for the $$ you put into the engine. The L6 heads flow better than you think and for a 2 valve head work very well. Hell the LY cross flow head which has a hemi CC are reportedly to only flow 5% more than the non-cross flow heads. I would love to get my hands on a LY head and see what my head guy could learn/improve these.

 

L28 with out much work should lay down 200RWHP in a S30 chassis. The 100HP per 1000cc at the wheels is what can be achieved from the L6 in NA form (assume all done correctly and money is no object that is what should be achievable). So it should be possible to get 280RWHP from a well worked/build L28 (might not be good for the road and will be all up top etc but doable)

 

So as Lurch has stated a L28 with the right setup will be more than enough power for most of us - however if you are racing other zed and you want the edge maybe a larger cc engine will help you (or not driving skill, chassis setup does come into it also)

 

Having owned/driven a large L6 engine 3.2l there is no mistake about the torque, but then having driven a smaller stroked L28 also (3.0 ie less than 88mm bore) that was build correctly it was the same as the 3.2l on the road (track was different as the other car was more track setup than mine). Now it would have been good to see the 3.2l with a different head as the head was.....well....to be polite not he best. The guy I sold the car to I also sold another head I had build by my head guy. This was designed for the 90mm bore had a very very mild cam and was worked to increase the combustion chamber so I could lower the CR down to pump gas manageable or 10.5:1 not the 11-12:1 it was with the head on the engine when I got. Anyway getting to the point - this very mild cam'd head with lower CR and pump gas only dropped 20HP at the wheels vs a large port, large cam, high CR head on race gas.

 

So the point of this is big cam, big port and poor head work can make power but a well build head with the correct balance of Air-in and Air-out with a smaller (not much more than stock I might add) cam and ports can make almost the same power - again balance.....

 

Wow what a pile of dribble sorry about that guys....typing diarrhoea

 

I could tell you how to tell the high nickel blocks from the non high nickel blocks but then I will have to kill you >:( I will one day - maybe on the next upgrade of my website (which is nothing more than pics currently) I will do a blog type site and put up a blog about the differences between the L28 blocks

 

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im not having a go at peoples intelligence.

All i want to know is what would be the best parts to use to make one. Not what would be better.. to stroke or not to stroke, Im not concerned on that issue.

 

Good info so far people. Im going to have to definately do alot of research in this area before i start delving into it with buying parts. I guess it may take a couple of goes to get the best setup.

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im not having a go at peoples intelligence.

All i want to know is what would be the best parts to use to make one. Not what would be better.. to stroke or not to stroke, Im not concerned on that issue.

 

Good info so far people. Im going to have to definately do alot of research in this area before i start delving into it with buying parts. I guess it may take a couple of goes to get the best setup.

 

 

I've built up a stroker that currently in my car. The best parts to use depends really on your budget as strokers can cost a tonn of money when built right. All up I spent around 20k on my engine. The only thing I didn't do myself (aside from all the machine work which is the bulk of the work) was the tuning. The machine work and custom parts will cost a heap of money. Like I had a custom billet steel flywheel made to take a GTR clutch, the flywheel and clutch come to almost 2k. I'm running multi throttle bodies too with a tripple coil ignition. That with the computer, fuel pumps and all will come to around 8-9k. In the end in my opinoin it is definately worth it though. I'm making over 220rwhp using a 74 degree cam and 98 octane. I set the rev limit to 7k and it easily reaches that without a problem and still has enough torque to acceleratefrom 50km/h in 5th uphill. Thats come at a 20k cost though.

 

 

 

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Good posts guys, nzeder I'm working on a new site as well with a blogging function, i know what you mean about it guys/panel beaters haha :)

Devilz good to hear some positive feedback for the stroker :)

 

Mtop, there are a few different combination of parts you can use. For mine I'm going with...

 

3.1 litre

 

LD28 crank (from diesel maxima)

 

Connecting rods from a 73 l24. From a certain point in 73 the rods came with a 9mm bolt as opposed to the 8mm bolt in the earlier engines and they are a little lighter. This is the ideal rod.

 

With an n42 head, you can use KA24e 89mm pistons (from a 200sx). With a 1mm head gasket you get a compression ratio of about 10.6:1 and mill the tops of the piston to get 10:1 or you can use a 2 mm headgasket to get about 12:1. However I have a spec sheet to get custom forged je pistons and I'll be using these in my build.

 

Then you'll want a new cam, I'm not sure what grind you would like/need.

 

You'll probably want to get some sort of extractors, I've got a Holley Red fuel pump and fuel pressure regulator (from memory about 3-4psi is ideal? also note that a lot of people find Holley fuel pumps to be noisy. I'm mounting mine on a huge rubber block to try and minimise the noise), lightened flywheel (to prevent crank failure again) and probably make sure you have a decent radiator. A 4 core would be good. And look at a decent harmonic balancer (there was a thread on here recently about different brand balancers i think)

 

Then there are all of the other small expenses, head bolts etc.

 

If you haven't already, pick up a copy of that book how to modify your nissan/datsun engine or something (also get the how to restore book while your there). It has good info on how to prep the block etc.

 

 

 

 

 

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Good posts guys, nzeder I'm working on a new site as well with a blogging function, i know what you mean about it guys/panel beaters haha :)

Devilz good to hear some positive feedback for the stroker :)

Re the blogging function - me too - I am in the middle of updating my website to a blog setup

 

Strokers are good to drive the torque is something else. Mine was building using L14 rods and Cosworth Forged items. Personally I would not want to go though all the trouble of getting the LD28 crank, rods, machine work balancing etc just to put a truck piston on the top (reads KA24 piston) the rings are large, the piston is heavy. Great if you want a cheap stroker (is there such a thing you have to ask) but for a few $$ more you get some nice light weight pistons, with a much smaller ring (not the truck sized of the KA24)

 

This is just IMHO - take it as you will.

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This is why I decided to travel OS for a while instead of continue with my L31 build. I realised how expensive it is to do it right. Plus to be honest I'm not sure I want to blow all that money on an L-series engine straight up.

 

I'm thinking of learning to build an engine on my own first, take a block apart, prep it clean it up, balance it a little, even give porting and polishing a go myself. Stick a mild cam in it and put the Triple Mikuni's on it, have some fun but keep it relatively tame.

 

I kind of want to build a real junkyard motor, that is a motor built with cheap parts in a junkyard and just see what I can achieve from it in terms of power and drivability. A well sorted L28 can be pretty damn quick.

 

I already have L14 rods and LD28 crank (thanks to Nzeder for completing my set of L14 rods). However the more I think about it the more I want to build something a bit different like an L24 with L28 crank :). Plus for me there's other areas of the car to attend to, such as the bodywork, brakes, suspension, interior.

 

Not trying to put anyone off, just putting it out there that a monster L28 is great but to be honest very expensive. Plus I'm the type that likes to learn (do it myself) and do things on a sensible budget.

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thanks to Nzeder for completing my set of L14 rods.

No problems - I keep my eye and ear to the ground on the hunt for more all the time too :)

However the more I think about it the more I want to build something a bit different like an L24 with L28 crank :).
That would be a L26 you are after then - same block P30 code, L28 crank and 83mm bore only different is the block is notched for the larger exhaust valves of the L26 E88 head = this is what you want anyway just get a L26 engine and be done with it.

 

Now if you were thinking a L28 with a L20a crank then you are talking different. Displacement would be around the factory mark at 2.4l but with a much shorter stroke of 69.7mm vs the 73.7mm of the L24 but with the larger bore of 86mm vs stock L24 at 83mm should rev hard.

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I kind of want to build a real junkyard motor, that is a motor built with cheap parts in a junkyard and just see what I can achieve from it in terms of power and drivability. A well sorted L28 can be pretty damn quick.

 

Wouldn't it be sweet if we had enough Zs in Aus to buy a cheapo one as a 'budget' racer the same as those guys (i think swiss?) in that top gear episode who build race cars to a set budget (say $3K) and if someone offers to buy the car at the end of the race they have to sell it for $3K.

 

That would be such a good way of learning to how to build your own motor, and you could experiment as much as you liked.

 

I visited Josepf's house the other day and he had the the head out and was in the process of bolting the carbys and exhaust manifolds back on, made me crave to have a project Z.

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