1970 240z USDM 432

[iwayman]

have you ever thought of putting an RB 20 or 25 turbo in?

 

I've always wanted to drop in an rb26dett, cuz those are supposed to be good to 600hp on stock internals, but I'm on a highschool budget and this is the most I've ever done on a car. Now that i've got some experience I plan to eventually swap an rb in once I'm making money.

[iwayman]

Well heres my new setup:

 

took it out for a test run, wasnt running too rich and dieing at all...

BUT for some reason i'm not making any boost past 0psi!! :confused:

I'm gonna go fiddle with my bov and wastegate in case theyre the issue. Any ideas, guys?

[fo0manchu]

vaccuum leak somewhere? Check where your maf sensor connects to your maf too. That is sometimes the culprit . Did you change some stuff on your intake manifold too? Also check for popped off hoses.

[iwayman]

I'm thinking the wastegate is stuck open but I havent fiddled with it yet. Other than the lack of boost its running real well! :rofl:

[fo0manchu]

nice! do you have an air/fuel meter installed yet?

[iwayman]

Not yet. Is there some way to run one in the place of my o2 sensor? I dont think my o2 sensor does much.

[fo0manchu]

okay, so a few posts dissapeared. If your ecu tune dissabled the o2 then you can run a wideband in its place.

[iwayman]

How can I tell if my o2 sensor works? Think itd be noticable if I just unplugged it and took it for a test drive? assuming the sensor does function

[fo0manchu]

yes i think you could tell a difference. Just don't drive it hard. With an A/f meter, if it was tuned with an o2 you can see the a/f ratio trying to find stoich at idle and cruising which is around 14.

[iwayman]

A friend and I went out and played around with his new dslr.

[iwayman]

[iwayman]

Made this for $15

[Syncro]

lets get a video of it running man! :frantics:

[iwayman]

 

Went to the local track on sunday for a little fun. Third time out the car just suddenly loses power and dies. Check the fuel, getting pressure. Tried turning it over a few times to no avail. I then stick my leatherman in #1 plug lead to check if the thing sparks. It sparks and fires up so I plug it back in and drive off the track. At this point I'm thinking im just out of gas since I dont really have a reliable fuel gauge. I head out to get some gas, I go 200 meters and it dies again so a friend and I go get some gas and come back. But it turns out it wasnt the gas beacuse it fills after putting two and a half gallons in. I check the spark at the plugs again and this time there is no spark so I check it at the distributor and it suddenly starts throwing fat sparks! Plugged it back in, started it up and left, but the weird thing is that none of my lights excluding my headlamps work now... Have any ideas what happened? I don't. I think my headlamps only work because I had been trying to wire relays into them.

 

Picture courtesy of me when I broke down that second time lol

[I'm BLUE]

*Tripple check your engine harness.

*Especially the area where you were working.

*bare wires ... Look for them especially where wiring is not snuffed down or snugged down to much haha.

*loose or corroded connections...

*use quality connectors (crappy ones cause issues ...)

S30/s130 bay harnesses are crispy enough as is haha.

 

* Take off clean/re-apply heat sync grease to back of ignition module.

* Take off distributor cap and check pickup or CAS wires (depending on year of zx transplant),or rubbing ... As well as connection. I could be slightly off on that terminology/placement of parts ..as I have never worked on an l28et Haha.

 

My s130 had a short in the ignition (+) part of the harness 2ft from the dizzy module. Soldered in new correct correct gauge wiring and has been great ever since.

[iwayman]

*Tripple check your engine harness.

*Especially the area where you were working.

*bare wires ... Look for them especially where wiring is not snuffed down or snugged down to much haha.

*loose or corroded connections...

*use quality connectors (crappy ones cause issues ...)

S30/s130 bay harnesses are crispy enough as is haha.

 

* Take off clean/re-apply heat sync grease to back of ignition module.

* Take off distributor cap and check pickup or CAS wires (depending on year of zx transplant),or rubbing ... As well as connection. I could be slightly off on that terminology/placement of parts ..as I have never worked on an l28et Haha.

 

My s130 had a short in the ignition (+) part of the harness 2ft from the dizzy module. Soldered in new correct correct gauge wiring and has been great ever since.

Thanks for the advice, I've been looking for anything out of the ordinary for my wiring. The z seems to be running pretty well right now, just did an oil change yesterday with 15-40 delo 400.

Only problem is that all of my lights are not working. I cant drive it anywhere right now because no brake lights or signals lol

All of my fuses are in good condition.

 

Does anyone have a wiring diagram for the light system? I've got a haynes owners workshop manual but it wasnt very helpful.

What can break that takes out all of the lights without burning the fuses?

 

here's a couple photos, too

[I'm BLUE]

240z's ... Have had at least 2 Headlight combo switches go bad. A lot of people complain about them as well. The powervwire coming in from the harness is usually burnt. The aftermarket relay harnesses for the Headlight and running light circuits are an excellent Idea ... but merely slow the issue down ( in my opinion not fact ).

 

Check power coming to it with a test light ... Or use a multi-meter (+) .... If none obviously inspect at the fusebox

 

If its bad .. or tight on money or can't find one ... Just wire in a couple cheap toggle switches very nicely.

 

 

 

[iwayman]

240z's ... Have had at least 2 Headlight combo switches go bad. A lot of people complain about them as well. The powervwire coming in from the harness is usually burnt. The aftermarket relay harnesses for the Headlight and running light circuits are an excellent Idea ... but merely slow the issue down ( in my opinion not fact ).

 

Sorry to be a bit of a noob but is this the combo switch?

[I'm BLUE]

yes sir !

 

If you don't have an MSA Fusebox "upgrade" I would suggest keeping an eye on the factory one AS well as looking for any sign of "melting" or distortion ( if any more than a speckle ,,, it warrants immediate attention ) ,,, they tend to melt on at least 1 circuit haha.

 

^^^ I stated this as it could easily be linked to your isse as well. If you clean it with white vinegar you will have a chance.

 

But as the old saying goes "Don't fix what ain't broke" as well as "an ounce of preventation is worth a pound of cure"

[datsundash]

You can put the maf after the turbo although I don't know how successful you will be with the stock 280z unit. Plenty of people have done that with other cars. It is a blow through setup instead of a draw through. Like I said before, check your BOV. It is running rich because your maf reads "x" amount of air, but when you let off your throttle and your BOV goes off that metered air is not reaching your motor but the atmosphere instead. Therefor you are running rich. That is also why you are getting backfires. Remember, your maf reads air and tells the ECU how much fuel to give.

 

you can remedy this by recirculating your BOV or tuning your ECU accordingly and adjust for the BOV. Hope this makes sense.

FAIL!!!!! The MAF is designed to read air flow atmostpheric pressure, if the MAF tried to read airflow that was compressed it would be very inaccurate. keep the MAf on the non charged intake side.

[iwayman]

FAIL!!!!! The MAF is designed to read air flow atmostpheric pressure, if the MAF tried to read airflow that was compressed it would be very inaccurate. keep the MAf on the non charged intake side.

 

I found this out a while ago lol I made a bov recirculation system for a few bucks and fixed all the issues.

[iwayman]

Didnt find any obvious wiring issues with the fuse box or combo switch. Rewired my headlamps back to stock (from DIY relay setup http://alteredz.com/Headlight_Relay_pg1.htm) and now my brake lights and signals work although my running lights still dont so atleast I can drive it during the day now :)

[fo0manchu]

FAIL!!!!! The MAF is designed to read air flow atmostpheric pressure, if the MAF tried to read airflow that was compressed it would be very inaccurate. keep the MAf on the non charged intake side.

You need to do more research on turbo cars and how things work. Many people use a blow through setup. Either way works. Maf reads air flow. You might be thinking about a MAP sensor that reads pressure.

[iwayman]

You need to do more research on turbo cars and how things work. Many people use a blow through setup. Either way works. Maf reads air flow. You might be thinking about a MAP sensor that reads pressure.

 

Actually either way does not work, or atleast it did not in my case. I ran it on my intake cold side and basically as soon as you start to boost (0psi) the engine starts cutting out. Only thing I changed was the maf so it had to have been the cause. I put it back before the turbo and made a recirculated bov system and now it runs great. I now run around 8 psi and after I weld up my intake piping I'll be able to increase boost more. Only thing holding me back right now is all my intake couplers, they keep popping off when I boost too much.

 

If you ran a flappy afm rather than an maf then maybe you could run a blow through set up. I have a ford maf so maybe that's why I couldn't run it on the charge side. I also know that its not a good idea since the maf also senses the air temperature and you can melt something inside of it if you run really hot air through it and it would throw the readings off. Either way I have tried running my maf after the turbo and I know first hand that it just doesn't work.

[fo0manchu]

Its more tricky doing the blow through setup. I think I told you about it, unless that post got deleted. I also said to recirc the bov too right? Anyways, to run a blow through setup, you need a good amount of straight piping and it cant be right next to the throttle body because you would get air reversion back through the maf. Also, a lot of mafs have small leaks around the electronics, so you would have to seal those up as well. Just do a google search for "blow through turbo setups" or "maf after turbo" and you'll see a ton.

 

Anyhow, maf before the turbo works well and is easier,imo. That's the setup I run.

 

What kind of intake pipes are they? Are they the ones with a beaded end?

If not, you can try beading the ends. Here is a home made pipe beader. I tried this and works well if you have a welder:

http://www.dsmtuners.com/forums/custom-fabrication/324132-homemade-intercooler-pipe-bead-tool.html