Why im choosing L28ET - Opinions?

[Deus Ex]

So as some may know after a year and a half in Canada i have my car back on the road.

 

Took off the P90 head after a timing chain failure and replaced it with an N42 to up the compression (F54 block, flatop pistons) and brought over the lump cam. The instant improvement in torque was amazing and for a while i was very pleased. The extra oomf would nudge it alittle closer to the very low 13sec mark and thats enough for me. But i have since found that the 20ltrs/100km im getting is just too much for me. Passengers complain about the fuel smell (Triple 45mm webers) and its a pig to drive around at anything but wide open.

 

So to get around this i considered selling it and buying something else. I couldnt do it.

 

:?: Then i though about an Rb20/25 conversion. Its just too much money when im not chasing big HP

 

:?: Then i thought about RB30. Easy to come by and cheap in Australia, put on an RB25 and mods keep going.

 

:?: But then i thought, why go to that trouble when i can just Turbo the L28.

 

Its a very rare thing to do in Australia, but i do have an FJ20 GB, P90 head, efi inlet manifold and Turbo manifold to make this idea more sensible. Plus my block has been balanced and blueprinted by previous owner.

 

So after alot of research (particularly the stickies on hybridz) i found that it would be very cheap and easy to re-valve the p90 (has a slight port work already), ditch the webers and just bolt on the standard exhaust/inlet manifold. Im sure it would have to deliver.around 250-300HP which is more than what im after.

 

I know that in the long run the RB will make more power and be more customizable, but because im not chasing that i think the L28ET would suit my needs.

 

Any thoughts?

[luke_mcmahon85]

do it man...then tell me how slash do it for me...hehe

 

i'm thinking of going the same route. were you going to go aftermarket ECU? i was thinking megasquirt

[Deus Ex]

Yeah i would def go an Aftermarket ECU. Mega squirt is dirt cheap but i wouldn't have the patience to tune it myself, i was probably looking at a Microtech, then i can do away with the AFM and have infinite customizing.

[620Z]

Just bear in mind you will still have the fuel smell in the cabin and it still won't drive like a modern car unless you do some Camber and bump steer mods.

[Deus Ex]

Trust me the fuel smell wont even be close to how it is now :wink:

 

I dont ask for modern car steering and such, it handles just fine. I want to be able to accelerate smoothly, drive it stop start traffic if need be, and not have my carbs need a tune every 4 months.

 

Plus many more lol

[XRQTR]

A stroked and de-comped L28/31 I dare say you could make the same if not more than most RB25's.

 

Don't forget it all comes down to how much you are willing to spend, a well set up N/A 31 sees over 300rwhp, throw a turbo on that after a decomp, some decent injectors, FMIC, give the head a bit more porting maybe a custom inlet and exhaust manifold ( which you would be able to adapt from other shelf items) and 500 comes on pretty quick.

 

note: girdles come in handy at this point also as well as decent rods, bearings and pistons :wink:

 

I am thinking about this route at the moment, although the blown injected Windsor will go in at some point I think this would be a good starting point for car that you can have a bit of fun with.

[sid280]

I've got a turbo and manifold to fit my L28, however the turbo doesnt have a wastegate because it used some kind of pop-off valve, so I picked up a 1JZ Single turbo unit, but since the old one is upside down i cant really bolt it on, and worry about clearance to the intake manifold - and its F54 / N42 so too much boost will kill it very quickly. In the end I think I will need to use a custom manifold or pickup a T3/T4 exhaust manifold from the states / nz.

 

Apparently - You can get around an ECU by putting putting a 660+ cc injector into your cold start injector hole, and connect it to a hobbs switch so that under 3-4psi of boost it activates it. I'm not sure about getting an even mix throughout all of the cylinders however it would help with the extra petrol, and since its compressed air it hopefully the petrol will turn to mist. I will let you know if i try it.

 

I'm hoping that a high compression / low boost combo will give me more low down power and help the turbo spool up faster, and help with fuel economy since the engine wont need to be in boost all the time. Timing is controlled by an MSD 6-BTM because it works with the non-turbo dizzy, on the downside it does mean i cant use an aftermarket ECU to control the timing, so hopefully the MSD's boost retard function does the job and stops any pinging - and a FMIC.

 

I've considered using a custom intake plenum but i figured compressed air will force its way through provided its smooth enough, i've even shelved my 68mm TB and ported intake because the 280zx doesnt have much in the way of piping allowances, and any chassis mods make it difficult if you get a canary - so a megasquirt and MAP sensor with 50-55mm piping are looking better and better every day. If they can fit 50-60psi into a skinny pushbike tyre, then i'm convinced 50mm is ample for 8-10psi provided you get rid of the AFM flappy thingy.

 

Anyway i say go the L28ET !

[Deus Ex]

A stroked and de-comped L28/31 I dare say you could make the same if not more than most RB25's......

 

Dude plz read my post next time :lol: im not after more power, im after similar power with better driving and less fuel consumption.

 

And i have no idea why you would de-comp a 3.1. And the cost of building a stroker? Forget about it lol. Not on a 30 year old engine no thank you :wink:

[sco_aus]

I've got a turbo and manifold to fit my L28, however the turbo doesnt have a wastegate because it used some kind of pop-off valve

Do you mean an external wastegate off the exhaust manifold? It looks just like a blow off valve, but different function. Hope im not patronising.

 

Sounds like a good plan, you wouldnt need much effort to do it all or money.

 

A stroked and de-comped L28/31 I dare say you could make the same if not more than most RB25's.

 

The thing that would hold it back is the SOHC, so like you said, how much would you spend.

[Scando]

Yep, go for it!

 

My L28 Turbo amazes me how it idles perfectly (even after it's just been flogged around a race track)

 

If you don't want massive power then don't decompress it too much (keep the compression ratio around 8:1) run low boost (8-10 psi) and use decent engine management so that you can have timing advance off boost and reduce it as it comes onto boost.

 

This way you'll still have good power off boost and with a intercooler and big exhaust you should get around 300HP.

 

Just remember you'll have to replace fuel pump, injectors, etc but it'll be worth it, trust me

[sid280]

I've got a turbo and manifold to fit my L28' date=' however the turbo doesnt have a wastegate because it used some kind of pop-off valve[/quote']

Do you mean an external wastegate off the exhaust manifold? It looks just like a blow off valve, but different function. Hope im not patronising.

 

Sounds like a good plan, you wouldnt need much effort to do it all or money.

 

 

Hey sco, its not an external wastegate its a boost control system which was used on the intake instead of the exhaust, basically a Blow Off Valve is used instead of a wastegate altogether in the 70's-80's, but i think a "Pop Off Valve" and "Blow off Valve" did operate differently but i dont know how.

 

The best I could come up with, was its part of a kit produced when the 280Z was first released, made by a company called Janspeed. Another company used a similar system with a carby turbo setup and i think that the manifold I have is for that and wont clear the EFI L28 intake manifold.

 

 

 

 

I still have the option of running without a wastegate but since the 1ZJ turbo has an internal one, I will just use that. This week a mate came back from overseas and said he could build me an L28 turbo exhaust manifold similar to the South Florida Performance (SFP?) ones you see on Hybridz, maybe under $500. I'm thinking about getting 2 made up - one with a smaller flange for a smaller turbo - just to see if the stock EFI will work with it instead of using a hobbs switch - something like an SR20DET stock charger - dont know yet, open to suggestions, would be good to get a cheap turbo recipe for L28's using easily accessable parts in Australia. [/img]

[sco_aus]

Haha, crazy 80s. Dose it Uleh!! haha, sounds like you have it figured out.

[thehelix112]

Apparently - You can get around an ECU by putting putting a 660+ cc injector into your cold start injector hole' date=' and connect it to a hobbs switch so that under 3-4psi of boost it activates it. I'm not sure about getting an even mix throughout all of the cylinders however it would help with the extra petrol, and since its compressed air it hopefully the petrol will turn to mist. I will let you know if i try it.[/quote']

 

That is such an incredibly bad idea.  And people are still surprised when they pop engines whilst using bullshit setups like that.  Do it properly, or don't do it at all.

 

...a well set up N/A 31 sees over 300rwhp...

 

Haha.. if  by `well set up' you mean `full blown race motor thats completely and utterly undrivable on the street'.  Or do you have proof of such an engine with usable torque from street rpm?  If so, I'd love to see it.

 

 

Deus Ex,

 

I say go for it.  The L28ET is a stout little engine as long as you take care of it.  That means a good fuel system, and good fuel/spark control: don't skimp on these things or you can be sure its a question of when, not if, they screw up and take your engine with them.

 

Dave

[Toecutter]

Just thought someone might be interested in this manifold and new turbo to suit L-series.

 

http://cgi.ebay.com.au/Datsun-240Z-260Z-Turbo-and-manifold_W0QQitemZ270150388597QQihZ017QQcategoryZ102336QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[modular9]

Toecutter : thanks for the find. I am in the market for better carbs or turbo or something.

 

Ok guys what else would be needed? I am assuming a high output fuel pump and larger lines like you need to do with an l28et swap. But i am not really up with what else. I have sent the seller a question as well. But thought i should ask the zed fellas here .