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[new title] 77 280z w/ l28et regeneration

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Oh yeah, Try doing a smoke test for vac leaks. That one helped me find a few. Block the AFM inlet with something (plastic wrap and a rubber band), then use a cigar to blow smoke in a vac line. See if the smoke leaks from anywhere.

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Yeah I should probably do the smoke trick.  Currently trying to get the stock pop off valve off so I can block that hole.  Its hard to get my boost up and to stay up.

 

Got a 240z front bumper mounted. 

 

My heater core valves were leaking and getting "new" ones or rebuilt ones is expensive so I am putting in a 3 way ball valve with some hoses to basically have an open to shut to the heater core system.  Trying to figure out with of the little vaccuum hoses in there go where so I can actually select which vents vs defrost might be tricky as the three i found weren't attached to anything.

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I'm a couple days into the road trip in the 280z and I've found that my mileage when I cruise around ~75 is 18.5 but if I cruise above 80 it drops way down to the 14s. I think I must still be running rich or something cause it should be better. Slowly dialing down the Afm and fuel pressure to see if that helps.

 

Car is running plenty cool and oil pressure has been good. I am losing brake fluid from the front brakes system. There are no leaks at the wheels and the master cylinder is also new and showing no leaks. Trying to find where in the hardline must be seeping.

 

Oh I should take a picture of my heater hack and will upload some photos when I have computer/wifi.

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I'm a couple days into the road trip in the 280z and I've found that my mileage when I cruise around ~75 is 18.5 but if I cruise above 80 it drops way down to the 14s. I think I must still be running rich or something cause it should be better. Slowly dialing down the Afm and fuel pressure to see if that helps.

 

Car is running plenty cool and oil pressure has been good. I am losing brake fluid from the front brakes system. There are no leaks at the wheels and the master cylinder is also new and showing no leaks. Trying to find where in the hardline must be seeping.

 

Oh I should take a picture of my heater hack and will upload some photos when I have computer/wifi.

 

Probably normal mileage. Wind resistance goes up 4 times when you double the speed. Wind resistance at 80 is four times what it is at 40. Adds up fast.

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I never had an S30 long enough to do a fuel economy test. My 280ZXs with a 5-speed were getting around 26-29 on the highway. Generally I was at 65-70mph. Stock 3.9 rear gear.

Now I briefly had the non-turbo engine with tall 5-speed and 3.54 rear, lowered car. I got over 30mpg on the highway. After the turbo swap I never saw those high numbers again.

 

My guess is that you should be in the low 20's or better if things are running correctly.

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Okay, been doing lots of driving.  Currently about 4500 miles on the trip so far and going pretty smooth.  I replaced my fan clutch in southern california cause it had seized but hadn't thrown the fan to pieces yet.  Only other thing is I have to keep topping off the disc brake master cylinder, going to put in a couple new hardlines while I am here in CO.

 

After fixing my timing and adjusting the AFM/fuel pressure a bit my MPG seems to hover around 20-22.

 

IMG_6837_zps9doaiovo.jpgIMG_7014_zpsfs6ptwjc.jpgIMG_7068_zpsmrvaj62m.jpg

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Hey all, I recently added an air fuel ration gauge to try and see if I'm running in the right range and it does nothing but say full lean no mater how I adjust the AFM or fuel pressure.  I tried going way with no change to the gauge reading so I am guessing/hoping its just somthing up with the gauge or how I wired it.

 

Anyone else have problems like this or a fix to try?  Its just +/- wires and a wire to the o2 sensor.  I think I should run a new section of the shielded wire because mine is in bad shape but not sure if thats what could be causing this.

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There are three types of O2 sensors that I know of. What type do you have in the car and what type is the gauge intended to be used with? ;)

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This car is still set up with the single wire, narrow band O2 sensor, as far as I know, the wide band ones didnt kick in until the later 80s 300zx ECU setups.

 

My sensor is an NTK specified for use with 79-83 280zx cars, which is the motor and ECU i have.  The air/fuel ratio gauge is an equus 8366

 

Im gathering parts to do the 300zx z31 computer, MAF and crank angle sensor.  The car is not actually running lean (as far as I can tell) and it survived that long roadtrip fine so I'l probably just wait till I do this swap to try again getting an accurate air/fuel ratio gauge working right.

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Get a legit wide band, preferably Innovate or AEM. Then research Megaquirt.

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The innovative Innovate Motorsports (3844) MTX-L Wideband Air/Fuel Ratio Gauge Kit, is real nice.. it can be stand alone, has data logging abilities and it has extra outputs to send a signal to an ecu.... plus i believe the computer program it uses allows for parameter changes.....

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I've been moving real slow on the 280z. Moved to Atlanta from Texas and had to get a different daily driver to use while I tinker on the 280z. Currently living in an apartment means no garage space.

 

I did the 300zx ecu conversion but am still trouble shooting it. The car had already had the 280zxt bits all moved around so even following Afshin's guide I couldn't do the fuel pressure relay mod in a smooth way. Right now it seems to run good at the start and then get worse as it warms up and gets to be running too rich.

 

The 300zx ecu is supposed to control the fuel pump rather than it always being on. I thought that that could be causing the rich situation....but with the fuel pressure being regulated at my fuel rail it seems like the pump being on/off/intermittent wouldn't force the extra fuel through. I'm going to try lowering fuel pressure. I tried turning the idle mixture screw on the MAF but it didn't do much.

 

I also need to learn the LED green and red blink language of this ECU so that I can see if there are other faults making it run in some kind of safe mode.

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