Nitrous on L28

[Gavin]

Just exploring the idea of adding nitrous for the $2006 challenge. I have 105k mile 78 L28 that runs great and am wondering how big a shot it can take. Anyone know?

 

Also this would be tuned with ignition as well.

[ww]

At least a 50 shot dry. You can probably do a 100 shot if you richen up the fuel. Even more if you go wet. What kind of shape are your diff and axels/ujoints in? LSD or no? What kind of tires are you gonna run?

 

I'd be more worried about breaking the ujoints than the motor.

[Gavin]

Well , to verify, I would definitely be richening the fuel at least with a sprayer like one that would come with a nitrous kit, if not with MegaSquirt. I guess 'wet' means its mixed with fuel before being injected? I have to read up on my NO2.

 

Standard non-LSD R200 diff right now, only 1 new axle haha but miles arrant too bad like I said. From what I understand I can get a junkyard LSD R200 from a 300zx? Will definitely do that one if budget permits. Everything looks/feels in fine shape though.

 

Plan on bringing a pair of slicks of some type for the 1/4 mile where I'll be using the NO2. Should I not maybe to go easier on my drivetrain?

 

Thanks!

[TheNeedForZ]

Nitrous oxide = N2O, not NO2

[ww]

Yes, wet means a separate line for additional fuel, usually as another 'injector' next to the N2O injector controlled by the N2O system.

 

The LSD ONLY came in the 1987.5 to 1989 model years of the 300ZX turbo. The NA and the '84 to '87.5 turbo was open diff just like the one you have. The supply of these is dwindling rapidly and unless you get lucky, it's getting more cost effective to just buy a new Precision Gear - Power Brute LSD ($600) assembly and have it installed in your existing diff. for another couple of hundred. You'll end up spending about $900 for the purchase and installation, but you'll have a brand new one and not a questionable one from the junk yard that may need rebuilt in a few months.

 

Bear in mind, this will put more stress on your driveline in the drag event and the sticky tires will make it even worse. That's why I asked about your diff and u-joints. If they're not up to snuff, you'll be pushing your car off the starting line when the tree hits the green light...

[Gavin]

Ya, N2O sorry about that.

 

OK so a wet system was what I was thinking of doing, since the cold-start injector is in a perfect configuration on the fuel rail for it.

 

You would be suprised what can be found in junkyards up here near Boston since people arrant really into this stuff round here, for whatever reason. $900 is way too much, so its that or nothing.

 

I know it'll be hard on my drivetrain, but I think I can restrain myself at launch. Perhaps I'll stick with sticky street tires.

 

So what kind of power should my r200 be able to take, assuming its in good condition?

 

Actualy hell I wouldnt even be spraying at the launch right? So couldnt be too bad.. right?

[510six]

I ran a 120 HP shot to the wheels on an all junkyard parts 3 liter stroker that was well built.The problems that I had was that the stock 225mm clutch will not handle the shock load that the N20 puts on it.Also an MSD 6A should be used as the combustion pressures of nitrous tend to Blow the spark out.If you can add the fuel via your fuel injectyors I would do so with the Mega squirt as this is really the idea way of adding fuel for N20 and another fuel system doesn`t have to be plumbed.I would talk to other Megasquirt users who have run a "dry" N20 system.Dyno tune sells nitrous sytem components for much less than NOS.

 

http://www.holley.com/HiOctn/TechServ/TechInfo/NOSTech3.html

 

http://www.megasquirt.info/ms2/

 

http://www.dynotunenitrous.com/store/Scripts/default.asp

[Gavin]

OK good to know so I'll get a set of MA70 injectors or something and use the MS. I have a set of MA70 coils for the ignition - I dono about the MSD since again thats money. Doesnt it only give multiple sparks below 3000 rpm or something anyways?

 

Thanks for the link to Dyno Tune I'll go with them.

[PUSHER]

could just weld your diff instead of lsd, you'll push a bit more in the autox though.

[z-ya]

I think you can use an external input to switch VE table with Meagasquirt. You will need to run the "Extra" code to do it. So your NOS switch could trigger the Megasquirt to switch to an NOS tuned VE table. It would be pretty cool if you could make it all work.

[510six]

http://www.msdignition.com/pdf/tech%20bulletins/tb_top_10.pdf

 

The CDI unit provides multiple sparks below 3000rpm but delivers a much hotter spark at all rpm ranges, it`s a very healthy spark as I have been shocked by one.I would suggest running somekind of CDI unit with above about an 80hp shot to the wheels.Keep in mind that for every 50 hp shot you wil have to reduce timing by 2*.

[Gavin]

I had thaught the MSD 6A was more expensive, but I see it on eBay for under $100 which sounds good.

 

Yes I was thinking about using a second VE table with the N2O. From the looks of this, though, it just adds a set amount to each squirt / RPM when the N20 relay is tripped. Or maybe I'm misunderstanding.

- Oh IC I can do either/or. Sick.

 

http://megasquirt.sourceforge.net/extra/nitrous.html

 

The scary part will be calculating just how much nitrous is being sprayed and what will be needed from the injectors to match it. Doesnt it change according to the pressure in the bottle?

 

Another thing - So once I add nitrous am I still tuning with AFR on my wideband or will that not be relevant? Would an EGT gauge be better?

 

Welding he Diff is something I hadnt thaught of. I have a spare R180 I could weld and swap in just for the drag, not sure just how much weaker that diff is though. I could find another R200 and do the same I guess. I'd rather have the LSD though for the autocross as well, its high on my list but I'm not forking over half my budget.

 

Thanks a lot so far guys!

[Guest ZFury]

Your set-up would all depend on how complex you are wanting to go. Plus the factor in deciding that is if you are going to drive the car off of NOS often. For a simpler set up you can use fuel soleniods with fuel jets to richen the fuel mix with the NOS. Can operate off of an easy one button set-up. Press a button and you get your wet NOS shot, let off of the button and it is gone. The automated MS way is great, but may be a little much for what you are doing. You may have to constantly have your laptop in the car to turn off your NOS fuel mapping when you arent using it.

[510six]

It is scary how fast a motor will rev once a shot of nitrous is activated.What I noticed in the Mega tune software was it incorperates a full throttle switch an RPM window switch and a coolant temp switch and will retard timing.A switch that is external from the computer will activate the other VE tabel so having to switch setting via a laptop isn`t an issue.Just hitting only a button on a wet sytem is a really easy way to damage a motor.Tuning N20 with a WB02 is just like any other air/fuel ratio just make sure your settings are rich then back it down to a safe 11-8 to 11-9 just make sure to run good fuel.The bottle pressure can be set between 900-1100 psi and still work fine.I have busted several R180 stub axels with sticky tires on the drag strip I would stick with a welded R200.

[Guest ZFury]

Like I said it all depends of how far/complex you want to go. You can ruin a motor with MegaSquirt too. No matter what you are doing, you need to know what you are doing. You can get more power from MS, but you can reliably put a one button set-up on a car no problem.

[RB26powered74zcar]

I ran a 120 HP shot to the wheels on an all junkyard parts 3 liter stroker that was well built.The problems that I had was that the stock 225mm clutch will not handle the shock load that the N20 puts on it.Also an MSD 6A should be used as the combustion pressures of nitrous tend to Blow the spark out.If you can add the fuel via your fuel injectyors I would do so with the Mega squirt as this is really the idea way of adding fuel for N20 and another fuel system doesn`t have to be plumbed.I would talk to other Megasquirt users who have run a "dry" N20 system.Dyno tune sells nitrous sytem components for much less than NOS.

 

http://www.holley.com/HiOctn/TechServ/TechInfo/NOSTech3.html

 

http://www.megasquirt.info/ms2/

 

http://www.dynotunenitrous.com/store/Scripts/default.asp

 

Would this be the best kit to buy for the money?>> http://www.dynotunenitrous.com/store/scripts/prodView.asp?idproduct=126

[AdrianZ]

it always scares me to hear n00bs talk about things they don't know much about. but it seems you got everything sorted out now.

 

I'd suggest going with a direct port 6cyl kit. you can drill and tap each or your runers if you have carbs. and the same can be done for a intake plume.

 

I have to try this mega squirt out it sounds niffty. i got friends using it but I've never dabbled with it.

 

here my my key notes

 

direct wet kit best thing to go with

ignition should be upgraded

can your drive train take it?

don't run it too long if you like your pistons (they will get hotter)

[Doug71zt]

I saw a direct-port system in action one night at Mission strip in B.C. I think that the guy is a member here too. Seems to me it was a 150 shot, which approx doubled the output of the EFI L28. Visually, it is an impressive set-up that just looks nasty. If I was going to spray only, without forced induction, it would be a direct-port setup.

 

He was taping his AFM back together after having a nitrous backfire. I believe he was running a WOT switch only, without an RPM window control. Missed a shift, got it into gear and floored it, triggering the system at too low an RPM. POW. Split the seam of the AFM housing, but amazing enough, didn't shatter the flapper. Taped it back together with racer tape, and carried on.

The L28 is a pretty tough motor.

 

Doug

[drzed]

Ya Doug that was cool eh? That was Terry from Washington but I don't think he is a member here. For a bone stock 280Z Terry managed a couple of quick runs before the explosion! And his setup did look very trick.

 

If you remember you and I talked for quite a while - I think I was just starting to run my 260Z - it was still brown and very dented and ugly.

[Gavin]

it always scares me to hear n00bs talk about things they don't know much about. but it seems you got everything sorted out now.

Sorry to subject everyone to my learning experience.. The point of this post was just to see if nitrous was even worth it. The dry system w/ MS control is sounding very appealing since I have to buy much fewer materials that way, plus honestly sounds easy to set up. For the ignition it'd be MS controlled with an MSD unit. As for the drivetrain I'll just have to cross my fingers I suppose.. and run street tires, and go easy at launch. I have no reason to run it with nitrous for more than 10 seconds or so at a time. If what I'm saying is off base and it sounds like there is something I dont understand than please call me out on it, thats why I'm writing this.

 

I do have things much more sorted out now, I just had a few peaces of the puzzle missing. About using MS, it works by sending a signal out to activate the nitrous, but does not add the fuel untill it gets a return signal from the relay. This is so that that between the two I can have things like fuel pressure switches for safety or even a button to activate the nitrous, but I think I'd just let MS handle it. Seams real safe to me since MS is activating the nitrous. Any ideas on how I could make it hold off on the N2O untill 2nd gear?

 

As for single/direct port, what is the advantage of direct port and is it really worth it in my situation? I don't plan on keeping the nitrous system on the motor afterwards (Or at least I hope the engine will be salvageable ) so I would rather not have mutilated my manifold. But I'll do it if its worth my time..