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Turbo L28 vs 3.1 Stroker L28


Mr Camouflage

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  • 3 weeks later...

Too late. I put a 3" unmuffled (track only of course) system on and went to do some tuning yesterday. Went to boost it in 3rd, and I now have a broken box. How sad.

 

I'm going to look at an RB30 5-speed adapted to L28 bell housing as a temporary measure.

 

Dave

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Natez - just a question for you - if you want your Zed to be a corner to corner car then the RB is not a good option (this is my opinion only). My reason for this is that the RB is a heavier engine = the Zed 52/48 balance will be changed = a lot more suspension work required to get a good corner to corner car again.

 

Again not a flaming just my opinion (+ I am old school all the way - showing my age now - just love the L Series it was what the car was designed around) If $$ was no object I am sure you would do the same as most of us find and install the S20 that was found in the 432zeds and the KPGC10 and KPGC110 aka early skyline GTRs.

 

Cheers

Mike

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  • 1 year later...

I cannot beleve that you guys think a stroker is so good!

 

what do you mean a L28T has the same power as a stroker l28? do you meen a std turbo l28 vs a stroker as thats not a real fair comparison.

 

Also Gav how much power do you really expect to get from your stroker?

 

I respect the fact you want a motor thats a bit different to the norm but I dont think its better than std l28 that has been built properly little own a turbo motor!

 

Sorry to be a prick but I just cant stand the rubbish about strokers being so good any longer :x

 

Also just as a final point the 2 quickest Zed cars around Phillip Island (I take this as a good mesure of cars allround) are both l28 that have been boared out a little (prob about 2.9L). Ans there have been two other race built zeds with strokers who couldn't touch them! (built by zshop)

 

So I have had my whine now so I will shut up!

 

By the way Sulio I wouldnt mind being in on the dyno test with my car when it done then we would have L28 L28T and L3.1(stroker)

 

I am happy to discuss this and qualify any of my points but I am not trying to pick a fight.

 

Ash

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hi Ash, this is an old one that dissapeared off the radar as Costa has!

As far as dyno days go I would like to organise something once I get a chance to finish the mild L28 I would like to get into one of these days but with the new house thats dropped off on the list of priorities for a little while. Where's your car at mate?

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That will teach me for looking at old posts and not reading when then were posted :roll:

 

showed up as a new post when I logged?

 

Cars going well thanks. Hows the house going?

 

Just got my RB25 for my other zed today. Nothing like starting a new project half way through another.

 

Ash

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  • 4 weeks later...
  • 2 weeks later...

I think I might be a good person to respond to this topic as I have had both engines in my car. Well I had a 3L L28, which wasn?t stroked, but bored out a lot to Just over 3L, revved nicely to 8000rpm, and currently I have an L28 Turbo injected.

 

Here are quick specs of both motors.

 

3L. L28????F54 block, P90 head, forged pistons, comp vale springs, 76* cam, 10.5 ? 11:1 comp ratio, ported head, Twin SUs setup correctly.

L28 Turbo ???GTR pistons, low comp 7:3 to 1, turbo custom cam, custom exhaust manifold, GT30 turbo, Autronic SMC etc.etc.

 

BTW?? the person who ended up buying my 3L motor raced in some class in QLD for 4 years finishing each season in top 5.

 

The 3L made about 103rwkw with SUs, can?t remember at what RPM, with webbers 45mm which I got later would?ve made about 130rwkw I think.

It drove very nicely even with 76* cam, as it did have 3L to help. The cam really came in hard at 4000rpm but it was still very flexible and drivable below 4000rpm as well.

The car made the best induction noise that I ever heard from a 6 cylinder. It also would spit out fumes of up to 3-4 meters as it was lumpy, and very noisy.

It made fantastic raw old school noise. I raced a 240z L24 Turbo, T28, old motec ecu ???? and I just beat the car. The other car was making 102rwkw.

 

However with SUs and 76* cam the motor wouldn?t idle below 1300rpm, it would get about 18-20L of fuel per 100kms taking it easy. With webbers around the city fuel consumption would be much worst.

 

The current L28 turbo makes 220rwkw (on Racepace dyno) at around 5500rpm, redlines at 6700rpm and it makes over 200rwkw from 4000rpm.

It is much more quite than 3L, just little more driveable down low below 3000rpm, most likely due to EFI. The car makes heaps of torque as it went through 3 gear boxes in 12 months (FJ20 modified box, L28 box, 1 mixed box of parts)

All 3 boxes had 3rd gear stripped when flat sticked rolling in 3rd gear (torque gear) Now I finally got the RB25det box in, no problems since. The turbo motor is far easier to live with on daily basis and fuel consumption is great. It?s about 11.5 to 12L per 100kms, and that?s not just cruising.

The car still makes that lumpy NA L28 motor sound, but once on boost the turbo makes a bit of induction noise.

 

I?d never go back to a NA motor again, unless it was for historic racing or some hardcore restore job.

 

However it all comes town to $$$. The Turbo motor makes more than double the power of the 3L in my case, however it would cost twice as much to build. Plus on top of that if you wish to push more than 200rwkw you will need a better g.box with a new tail shaft, put in CV shafts, get a good LSD in an lower ratio ie. 3.5 or 3.7, modify fuel lines, add electric fuel pump or pumps, surge tank recommended, Once you?ve done all that you need to upgrade your brakes to get engineers certificate (another $500)

 

3L is better option if you are on a smaller budget or want to maintain old school look and feel etc. However if it will be carburettors (webbers or similar) you won?t want to use it on daily basis as fuel consumption will kill you. To build EFI 3L stroker with throttle bodies cost nearly as much as a turbo motor.

Once you built your 3L stroker, you?ll proudly be cruising down the street and you?ll have a P plater rock up in a 15 year old Silvia with a T28 on it that he got for $1200, kick you?re a$$ sounding like a law mower with an oversized exhaust, you might rethink you engine 

 

P.S. I do have a friend whom has an old silvia with T28 that did 12.4@109mpg (on slicks)

 

The best value for money is a RB30 turbo motor as you can keep fairly stock and still get good power out of it. It?s relatively easy to install, cheap and easily available. Stock-ish motor will easily make 200rwkw with a few bits and make loads of torque.

 

If you feel brave and want the smoothness of a twin cam motor go RB25 which standard bottom end should be good for about 245rwkw, but will need bigger turbo. Stock turbo is good for 190rwkw max. If you feel even braver and you just sold a kidney, go for RB26 which with stock turbos will make up to 255rwkw on 15psi, but you will need cam gears and good exhaust.

 

I was lucky enough to get a RB26 from a friend for dirt cheap price (no turbos) going single turbo anyway, so 1 day when I get my sh!t together and put it in, I?ll be able to do the compare of the 3 motors lol 

 

BTW ??.Gav when I took you for a spin last time, car had the old crap laggy turbo with 190rwkw, new GT30 is so much better.

 

P.S. I am happy to do a dyno or 1/4mile compare vs a 3L stroker??.. Quarter mile I?ve done 12.12@117.5mph on pulp fuel street 18? tyres. What?s the best time for a 3.1L stroker and with what diff ratio? I?m sure ?thehelix112? will be happy to help too ;) He has a nice GT35R on his car.

P.S.2 This strictly for scientific and education purposes only ;)

 

 

OMG ?? this report felt like doing home work???.. lol

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Great reply RPMZ :)

 

I am building a 3014cc non stroked L28 ie 4mm overbore = 90mm bore :shock: I will be running triple throttle bodies so it should be a bit more street able.

 

It is funny how different cars do different 1/4 times there was a racing zed here in NZ, now fitted with a 350 V8 (circuit track) that went down the 1/4 on one of the clubs drag days. Its time was 13.1 @ 105MPH now here is the good bit the engine setup.

 

Stock L28 bottom end balanced and the usual race pre work

Stock L28 dish pistons (yep dished pistons stock 86mm sizing)

Head E88 from 260c (the 4 door sedan) modified so with the dish pistons 10:1 CR - I think the cc were 34 with stock L28 valves MSA stage III cam.

Modified mikuni 44PHH (modified in Japan)

R200 3.9 Locked diff

CV setup and 6 pots brakes on the front and 2 pots on the rear.

Made 150rwkw with 7800RPM rev limit

 

I know these claims about the engine to be true as I helped (goffer) assemble/install this engine in the car.

 

I am very surprised your 3L only put down 103rwkw - I have seen a few stock sized L28 put down 130rwkw here (again balanced and head work but still 86mm bore and triples)

 

Re the fuel consumption thing - care factor: It is a sports car after all if we were concerned about fuel consumption we would not be playing with zed cars but this would be an electric car forum or alt fuel forum :lol:

 

Will be great to get your feedback on the RB engine install one day :)

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NZeder .........sounds like a really nice engine you are building, especially being EFI. What computer will you be running.

I mentioned fuel consumption as I know a few people in the Zed community here like using their cars on daily basis. I personally don?t, as I wouldn?t want to be stuck in traffic on the way to work and back, however not everyone has the luxury to have 2 cars.

 

The 103rwkw doesn?t sound like much, but it comes down to who?s dyno you use. I saw an race build L28 with triple Webbers, 74* cam make only 102rwkw, so in my opinion dynos are for tuning and if people want to compare figures, they should comparing their ? mile slips and what MPH each car is doing, that way you get a better idea how much balls the car has. The times might be all different due to tyres, suspension, traction etc. but MPH should be consistent.

 

With 103rwkw I still think car would?ve done high 13 second pass as it had 4.11 LSD, therefore the ratios were rather close, plud I did race a car that did 13.9, and I was tiny bit quicker.

 

With 150rwkw you should be doing low 13s with around 105mhp?????? let us know how you go ;)

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Hi Guys, I have to agree with RPMZ about the dyno's. They can be adjusted to give a higher reading. If you want your dyno to read higher then the other guys shop down the road you adjust it so it looks like your a whizz tuner. Dyno's are great for before and after comparisons or for checking fuel /air mixtures under load. Once you do your tuning adjustments the vehicle should be tested under the conditions you would be normally using it for. EG: road or track. Just my opinion. Have a nice day. David.

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NZeder .........sounds like a really nice engine you are building' date=' especially being EFI. What computer will you be running.

I mentioned fuel consumption as I know a few people in the Zed community here like using their cars on daily basis. I personally don?t, as I wouldn?t want to be stuck in traffic on the way to work and back, however not everyone has the luxury to have 2 cars.[/quote']

 

Yep I know what you mean re stuck in traffic - I lived in Melbourne for 2 years now back in Auckland, NZ and Melbourne traffic is great it moves at least - One winter it took me 4.5 hours to get home from work (through the single motorway that Auckland has) and my total trip is 65km's so that was 14.4 km/h (still quicker than I could run :lol:) + my zed has been of the road for 10 years getting its rebuild (as stated move to Oz, then back, built a new house, had a kid, got another on the way..yada yada). But good things take time :)

 

Re the computer - I am have a play with a Megasquirt :) I will be running either coil on plug or the six coils wired in a wasted spark config. So the megasquirt will be modified for 6 coil drivers non the less - just a question on the number of output I want to use. If I go COP I need to use 6 outputs which means I have to give up the knock sensor input (current software has knock input on the same as Spark F output)

 

So my question for those in the know - would an engine with the following specs need a knock sensor.

 

3014cc L28 with 90mm bore, 10.5 CR, EFI, Balanced crank, rods, 44mm intake valves, 38mm exhaust, .480-----270 degrees cam (not 100% leave that to the head builder - it will be custom to suit the engine)

 

So if I don't need a knock sensor I could do the COP thing. But as stated I will be running 6 coils either way.

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personally I'd run a knock sensor on any tuned vehicle, regardless of setup.

 

However, if you are tuning it on a dyno, with someone who has equipment to detect knock, and don't plan on fiddling with the tune after its been set, you probably could go without, if its tuned properly (IE. Safely.) and if fuel in New Zealand is consistent octane rating all the time.

 

However, for mine the safety net of a properly setup knock sensor is probably much more valuable.

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personally I'd run a knock sensor on any tuned vehicle' date=' regardless of setup.

 

However, if you are tuning it on a dyno, with someone who has equipment to detect knock, and don't plan on fiddling with the tune after its been set, you probably could go without, if its tuned properly (IE. Safely.) and if fuel in New Zealand is consistent octane rating all the time.

 

However, for mine the safety net of a properly setup knock sensor is probably much more valuable.[/quote']

 

Yes that is were my head is at also - go the knock and just have the 6 coils in wasted spark setup using only 3 outputs :)

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http://www.ozdat.com/forum/viewtopic.php?t=7489

 

DIY manual knock sensors, for the set-and-forget. Thats what I have done. The headphones are amazing, you can hear the valves opening and closing and ANY detonation straight away.

 

Electronic knock sensors are of relatively limited value I believe, though at the same time I am sure they are evolving and improving all the time. By the time the sensor is sure its detonation you could have a broken engine, esp on a highly-stressed race engine.

 

I'd say tune it safe, use good fuel, and forget about it.

 

Dave

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  • 8 months later...
  • 1 year later...

Exuse my ignorance, But how do you get 3.1L in a 'L' series motor? What crank or bore size are we using?

 

I have a Fuel Injected L28ET with P90 head. I am not sure what the block is I will have to check.

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Take the bore out to 89mm (3mm over) then get hold of a LD28 (Diesel engine - came in the Laurel's that are imported here in NZ not sure about OZ, we get them for between $50-150 for a crank only or sometimes the whole car for $100-200 which include a long nose R200)

 

The LD28 crank is 83mm vs the L28/L26 79mm. Using L24/L16 or L20a (pre 79) rods (all these rods are the same if the later L24/L16 units are used which have the 9mm big end bolt vs the earlier 8mm) I believe it best to use a good custom piston not the KA24 pistons as these are heavy and have large rings not ideal for performance IMHO.

 

You can get larger I have build L28 block with 90mm bore and owned one with 90mm with the LD28 crank = 3.2L now if you were to take a LD28 offset grind to change the stroke some more maybe 85mm then a 3.3L could be possible but at the 90mm bore the walls are getting thin

 

Hope this helps.

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It really does come down to peronal perfence from all I have seen and the biggest deciding factor is; 1. Do you want a nostalgic car or 2. A tuner car. For a nostalgic car i belive a stroker would be best. For a tuner car put in a RB engine and let loose. That leaves the turbo plenty of power, plenty or money [insurance parts]. Me myself i eventually money permitting, i want to build a twin turbo stroker bit out there and its a going to take time but awesome fun when finshied.

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  • 1 month later...

Hi All,

I don't have any experience on turbo L28 setups but I did build an stroker for my 240Z last winter and thought I would share what I have learnt and where I am with it now. There are many stories about strokers failing and this is mainly due to the use of pistons from other Nissan motors that really aren't suited. A custom piston with be forged, half the weight and have thin rings which is what you want. I had  JE make a set of 87.5mm custom pistons which I attached to a set of highly prepped L24 rods that were bushed to allow the pins to float. All rotating parts must be balanced as they have all come from other engines and must now work together.

 

As the engine is now 3 liter you need to do some serous head work, large exhaust valves and porting to get the gas flow up. The intake side is not as important but still should be cleaned up. To get the valves to open long enough to get the mixture in and out I used a cam with 535 thou lift and adjustable cam gear.

 

I used Mikuni 44's with 39 chokes and a custom 1 3/4 header which is split until it gets to the dif then joins into a single 3" pipe. This combo makes 335hp at the flywheel and 286 at the rear wheels and is very streetable. Off the cam its got torque and when it gets to 3000 it pulls hard to 7000 where its all over. It should rev higher but with 44's I cant get enough air into the engine.

 

One problem I found very early on is the uprated clutches sold don't last long and are to heavy causing nasty harmonics in the engine. I now use a flexplate type setup with a steel button in the middle with a 71/4 twin plate clutch and what a smooth engine it makes. Over the winter I am hoping to find a few more hp by doing more head work and fitting some larger carb's.

 

I have to admit I didn't build the engine myself I worked with an engine builder and my original budjet was 5K and I spent over 10K before I was running.

 

Ricky

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