55 replies to this topic

[Randall]

I just rebuilt a flat-top motor with p79 head. I currently have triple webbers installed and they are in need of a rebuild. So instead of rebuilding them I am thinking of selling and going megasquirt and maybe a turbo.

Here is a list of everything that i can think of at the moment:

intake manifold
fuel rail
injectors
fuel pump
fuel pressure regulator
megasquirt
wideband sensor

If i go turbo what else will i need besides the turbo and turbo exhaust manifold?
Will a turbo run fine on the 8.8:1 compression vs. the 8.3:1 of the turbo motors with dished pistons?

Just trying to get a list together i will be purchasing everything on the list above plus a turbo from a guy on craigslist. The megasquirt and wideband and fuel pump will also be purchased separately.

[dexter72]

To run Megasquirt: G.M. Intake air temp senor. 240sx or any 1995 on up Throttle position sensor. The older TPS sensors are just an on off sensor. Wiring harness from megasquirt ecu to engine. Relay Board or make your own relay Board. Laptop to tune your engine.

Yes with Megasquirt you can run the higher Compression engines no problem.

[Randall]

Could you do without the tps and just run MS with map and iat sensors.

Relay board?

[Randall]

http://www.diyautotu...441bd5a94e97586

Will this work?

And I looked up their relay board and understand what you meant.

If I use tps and iat will I need a wideband or could I get away with a narrow band until I start boosting?

[letitsnow]

Read the megamanual and search the MS section here, you need to have a good understanding of how things work if you want to end up with a successful install. You don't need a TPS, but it's nice to have.

[FricFrac]

For the MegaSquirt

- You need to figure out how you are going to trigger your setup and what type of ignition system you want to run. If you are using a dizzy/single coil, wasted spark, COP/CNP, etc.
- TPS is worth the minor effort to install.
- Wideband O2 is recomended.

For your FI conversion you bascially just need a EFI plenum that's populated as you stated above - injectors, FPR, fuel rail are all there. If you are going turbo you'll probably go to bigger injectors, different rail for o-ring injectors and a different FPR. Something to thing about instead of buying stuff twice.

Turbo is the same thing - yes you need the manifold/turbo but are you going stock? If not will you need an external wastegate, BOV, intercooler, piping, etc, etc, etc. If you go stock you'll need at minimum a j-pipe but if you are going through all this effort it would be best to have some sort of intercooler setup.

[Gollum]

Fricfrac is spot on.


The TPS conversion is easy as pie with a 240SX throttle body. If you find the right one it even has a spot to hook up the older style on/off tps plus the fully wiping tps.

Definitely consider heavily your goals and if it really makes sense to buy stock turbo parts (like injectors) versus new parts. In many cases getting new aftermarket stuff just makes more sense, so shop around and compare your shopping cart to your goals in mind. If you only want 250whp then an all stock setup+intercooler is fine, but you've already mentioned MS which makes me think you want room to grow beyond that.


So here's a more complete shopping list recommendation:


Intake Mani
Turbo Exhaust Mani (you could make one if you have the skills, but the OEM is fine well up to 500hp and beyond)
Fuel Rail
Injectors
Adjustable Fuel Pressure Regulator
T3/T4 Turbo
Downpipe
Intercooler
Plumbing for intercooler
240SX throttle body
240SX TPS
GM Intake temp sensor
Known good coolant temp sensor that you can calibrate to. Many use a GM sensor that there's solid calibration figures for, but you can also use the nissan one.
MS ECU
Relay board makes wiring easy and/or MS pre made wiring harness is nice too.
Wideband controller
wideband sensor
Laptop (netbooks make great tuning laptops as the battery lasts good and long)

It can get expensive, but like I said, really evaluate what you really need for your goals. Don't go spend $300 on a FPR, or $600 on 800cc injectors... Think system, make it all match for what your goals are. It really helps keep your head on straight and not go over budget.

[Randall]

Thanks for the input guys

I'm kinda looking at the 250 horsepower figure for now

I found a guy selling manifold injectors fuel rail wiring harness to splice stock turbo and fpr for 280zxt for 125

So that leaves me with fuel pump mega squirt and tps and possibly wideband

[Randall]

Also I mainly want to get it running n/a before I start into the turbo

What kind of waste gate bov inter cooler setup should I be looking at for stock turbo and injectors

Also I don't have any plans on changing out the dizzy/coil any time soon

[Six_Shooter]

For the MegaSquirt

- You need to figure out how you are going to trigger your setup and what type of ignition system you want to run. If you are using a dizzy/single coil, wasted spark, COP/CNP, etc.
- TPS is worth the minor effort to install.
- Wideband O2 is recomended.

For your FI conversion you bascially just need a EFI plenum that's populated as you stated above - injectors, FPR, fuel rail are all there. If you are going turbo you'll probably go to bigger injectors, different rail for o-ring injectors and a different FPR. Something to thing about instead of buying stuff twice.

Turbo is the same thing - yes you need the manifold/turbo but are you going stock? If not will you need an external wastegate, BOV, intercooler, piping, etc, etc, etc. If you go stock you'll need at minimum a j-pipe but if you are going through all this effort it would be best to have some sort of intercooler setup.

There are plenty of aftermarket or donor turbos from other vehicles that use internal wastegates, an external gate is not a "necessity," nor is the intercooler (though highly recommended), or BOV (but again highly recommended).

I've seen many low pressure systems installed that would be very similar to the stock set-up on the L28ET, without issues.

For many people that have not installed or worked on a turbo system previously, it is a good idea to start with a stock donor system, or something very close, get that running well, then move up, add on and change from there, to gain a larger understanding of how the system works and what changes have what effect.

On the flip side, if you're like me, do lots of research, and understand how the system works, you can piece together a custom system the first time with success. Copying someone else's system that has your requirements and goals already met is a great way to get a system together as well.

I couldn't agree more about wanting 250HP or so in an S30, being a great HP point. I have around 300HP in mine right now and partly due to the old hard tires, I have a hard time getting traction. With the power I do have, it's almost "too much," I can get myself into trouble pretty quickly if I'm not careful. I can barely wring out the first two gears, let alone any higher gears on the street, just too easy to break the speed limit. That being said I am shooting for considerably more power in the future, but not because I need it, just because I want it, and I wouldn't want any less power than I have right now.

[Randall]

Just bought a turbo exhaust manifold and will be picking up the intake and turbo Monday.

So that leaves me with mega squirt, fuel pump, and tps

[Randall]

Is the stock 280z fuel pump enough or what should I be looking for

[78zstyle]

Is the stock 280z fuel pump enough or what should I be looking for

should be, if you want to upgrade, get a walbro 255 inline pump.

[pcakes55]

You'll also need either a turbo oil pan and TURBO oil pickup tube (the N/A pickup tube wont fit the turbo pan). OR, what I did, was welded an oil return into the N/A pan; probably the easier route.

Edited by pcakes55, 14 March 2012 - 05:29 AM.

[Randall]

Yeah I forgot about that. Would it be alright to weld one in with the pan on the motor? Also where does the oil supply from the turbo come from? T off of the oil gauge?

[thehelix112]

Small clarification, the stock L28ET is 7.38:1 compression, not 8.3:1. Sounds like you are on the right track! Good luck.

And yes, I ran my oil feed for the Turbo from a T at the oil pressure sensor and -3 AN from that, so can definitely be done that way. I also welded a bung onto the stock L28E sump right below the scavage tray. Also run as big a drain from the Turbo to the sump as possible, you dont want oil backing up in the Turbo and blowing the seals. I ran -10 lines and didn't have any issues...

Dave

[Randall]

Awesome I can't wait to get this started...

I just spent all spring break doing the 240sx 5 speed mod and it turned out really well. I love the Megan short shifter!!!

The only thing that bothers me is my lifters seem to be louder than they should. After doing a full motor rebuild

I have done the valve lash multiple times without positive results

The valve noise also seems to come and go. Oil pressure after rebuild was 10 at 1000 rpm and went all the way to 60 psi

But after the lifter noise started I checked the pressure at idle and it's hanging around 20 psi. Blockage?

I'm using a 10w-40(i think quaker)here in Texas with no zddp additive.

I didn't have the noise until after the first 1000 miles or so after the rebuild and used a zddp additive on the break-in oil but not after. I also have close to 3000 thousand on the rebuild.

Also i overheated the motor after it was rebuilt due to radiator problems but i don't think it got too hot. Compression after 3000 miles turned out to be 175 to 180 on all 6 cylinders.

Anyone got any ideas?

Edited by Randall, 19 March 2012 - 11:57 AM.

[Randall]

Anyone?

[NewZed]

Maybe it's the injectors or an exhaust leak. Maybe the lash was too tight before and now that it's right, you're hearing normal noise. They are noisy, in general.

[Randall]

So I think I'm going to be ordering MS2

From what I've read yal recommend the walbro 255lph for fuel pump

What are your suggestions for fuel pressure regulators? Stock setup?

Also the injectors I received are the stock 185?cc injectors.

So I plan on getting the MS2 running on stock fuel setup first and then purchasing larger injectors and installing the turbo.

What would be a good injector for when I go turbo? I see the stock turbo injectors going for 150 for 6?