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Nana Spec 69' 510


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9 minutes ago, slowlearner said:

I can still smell the fuel on me a day later. Enough whining...

 

Justified. Playing with fuel is the worst.

 

I recently discovered that sprinkling year old molasses over the lawn is a similarly heady experience.

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10 hours ago, slowlearner said:

I didn't realize molasses was that potent. What does it do for a lawn?

It smells like an over fermented brewery, which depending on your tastes, may be a good or bad thing.

 

I had it leftover after having it in the fuel tank to remove the rust. Part of the reason I used it was because of the easy disposal.

 

As for the lawn, it's great for feeding the soil microbes, or so I read on the Google.

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Ok, so I've been flogging myself for the last week or so trying to get the datto back on the road with the EFI all working. I can't remember all the things I've been doing, but it involved a LOT of mucking around. Fans in and out like 8 times. Fuel pump in and out three times. Exhaust hanger. Relays. Wires. Fuel lines. You get the picture. Anyhow, it works... almost. Sorry I don't have more pics, but my phone sucks ATM.

 

IMG_20211028_115734_034.thumb.jpg.2b8782f31459491333b338d5a5adbe6a.jpg

 

IMG_20211028_115811_704.thumb.jpg.1a3b0a90340e80a95d605b2aa03e1242.jpg

 

The good news;

Fuel system works

Ignition works

Car runs

Car has 2 rad fans now if for no other reasons than letting a little more air escape during normal running.

 

The bad;

1. The inlet manifold has a huge coolant leak. Needs a block off fitting.

2.I have a HUGE intake leak somewhere. I suspect it's between the air box and the spacer tubes. Have to pull this apart see if I can fix it.

3. I'm getting a steady leak around the injector seals in the fuel rail. I was worried about this as I was concerned I'd drilled the rail slightly over size. Is there a hack for this? A little sealant maybe? 

 

 

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Update.

 

I managed to sort the injector leak issue and the coolant leak. What I can't seem to fix is the MASSIVE vacuum leak. Basically you start the car and it races up to the rev limiter instantly. Initially, I thought it was the idle valve leaking or a flange. Having fixed both of them, it did the same thing. I've come to the conclusion it's the airbox leaking. I put a whole new seal in it, but I think it's just not up to it. 😞

 

So, tomorrow I'll be building a plenum. Hopefully that sorts it. I guess I can sort out my packaging issues at the same time.

Edited by slowlearner
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Dragged myself out of bed today and hit the shed ready to make a plenum.

 

IMG_20211104_101945_626.thumb.jpg.d9d15d631e130b62f9ea184b17111d46.jpg

 

I was all set to make it out steel sheet when I found out our other car was ready to be picked up (broken boot latch). While at the workshop, I dropped in at the steel supplier and grabbed at 3x3" box section offcut. Instant plenum.

 

IMG_20211104_160144_133.thumb.jpg.275bd9c40f2a27f4de32bf62778abab5.jpg

 

After a bunch of MIG welding (metal in gap) and plenty of grinding, I had a finished plenum. Don't look to closely, lol.

 

IMG_20211104_200320_661.thumb.jpg.53558295a33a3a90275f651b5e3939d6.jpg

 

The paint's drying now so hopefully I can put it all together tomorrow.

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4 hours ago, slowlearner said:

Dragged myself out of bed today and hit the shed ready to make a plenum.

 

IMG_20211104_101945_626.thumb.jpg.d9d15d631e130b62f9ea184b17111d46.jpg

 

I was all set to make it out steel sheet when I found out our other car was ready to be picked up (broken boot latch). While at the workshop, I dropped in at the steel supplier and grabbed at 3x3" box section offcut. Instant plenum.

 

IMG_20211104_160144_133.thumb.jpg.275bd9c40f2a27f4de32bf62778abab5.jpg

 

After a bunch of MIG welding (metal in gap) and plenty of grinding, I had a finished plenum. Don't look to closely, lol.

 

IMG_20211104_200320_661.thumb.jpg.53558295a33a3a90275f651b5e3939d6.jpg

 

The paint's drying now so hopefully I can put it all together tomorrow.

 

MIG is Metal Inert Gas.

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18 hours ago, MikeRL411 said:

 

MIG is Metal Inert Gas.

 

I know! 😁 But most of the time it's 'metal in gap' around here. 😉 

 

Great news! The car runs!!!

 

Pete Wood (@reverendrally) • Instagram photos and videos

 

After spending all afternoon and evening last night installing the new plenum, I still had a massive air leak. However, I went through every flange with a light smear of sealant (ok, maybe heavier in some spots) and it's running. I now have to tune it, but it's finally working. Yay!

 

 

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Over the last two days, I've been getting the car running and tuning it. I had a bit of an issue with the fans, which turned out to be a dirty, old fuse holder. That's sorted now and the car drives so nicely. The combination of a really light gas pedal and super responsiveness is so lovely to drive. You can see a vid of the car running here.

 

Instagram

 

Thanks to everyone who helped me out with this. I've still got some things to sort with the tune and some wiring, but the car feels completely different to drive. I honestly can't believe the difference. The SUs were pretty good for what they were, but the big single TB/plenum and long runners are a revelation. Instant, big torque and the car rushes up to the 6000rpm redline. 

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Alright, so I'm kinda in uncharted territory now. I've been doing a bunch of tuning on the datto. I started with this AFR (air fuel ratios) table for Megasquirt.

 

This are the safe AFR and Ignition advance tables.

 

1493631368_SafetuningAFRs9_11_21.thumb.jpg.281b05d1d9c901d1a00aef84802ee1ef.jpg

 

1619805496_Safetuningsparktable9_11_21.thumb.jpg.673b1e2d931e93212f30bc925e1b5a6c.jpg

 

But really, with these are I'm not getting the best from the EFI. It is possible to run the motor a lot leaner in cruising state by advancing the ignition 3-5deg. It's a lot better for fuel economy and the engine actually runs cooler. I did the very same thing on my old VW flat four and it worked a treat.

 

1532229701_EconomyAFRs11_11_21.thumb.jpg.2058a1efe6606534ebb74aa70b729de8.jpg

 

9624677_Economysparktable11_11_21.thumb.jpg.d599adc54a5ec8f875f1e394d83889d5.jpg

 

My issue is, I don't really know the sound of the motor of L series motors. The new setup has some interesting new sounds. A sort of whistle at low revs under load. Then a sort of sizzle under load in the mid range. I pulled some advance out and got rid of the sizzle (which I assumed was slight pinging). I'd appreciate your input on this. I can get the fuel mixtures right with the wideband 02 sensor, but healthy ignition advance on Dattos is a mystery to me. 

Edited by slowlearner
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  • 3 weeks later...

I've spent the last few weeks fighting intermittent issues. First up, the toothed wheel was rubbing on the waterpump pulley. Having shimmed the toothed wheel and sensor mount, I started having issues with the crank angle sensor. What a pain. The car drove perfectly before and now it was stumbling and the fuel pump relay was turning off all over the place. I tried a bunch of stuff.

Sensor

Wiring

Mount

Plug boots

Datalogs traced a sync losses. Tonight, I think I finally figured it out. Something near the sensor or lead was adding electronics noise to the signal. The noise was causing the sensor to read wrong and make the motor stumble. I think what has been happening is the crank angle sensor wires have been flapping against (or close to) the alternator. This makes sense because it an alternator creates a huge magnetic field. So I strapped the lead back where it was before. The signal issue seems to have gone away. I'll test it properly tomorrow.

 

IMG_20211126_214706_077.thumb.jpg.127ee4c16953dae61f1f08209697ff97.jpg

 

 

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Solved!!! Yay! 😃

I have 2005 Golf wasted spark coil packs and leads on the Datsun. With the coil on the rocker cover, I had 3 unnecessarily long plug leads. So I cut the resistor/shielded ends of and installed normal silicon boots and clips. 
But not on all of them.
This where I made my mistake. I suspect the car would have run fine with all normal, or all resistor/shielded. However, with the wasted spark setup, I had cyl 1 with much bigger resistance than cyl 4. As the coil heated up, it must have been throwing all sorts of weird noise. That's what was shutting the ECU down. 
So today, having figured it out last night in bed, I ordered a new coil (they had one on the shelf) and leads. I also put resister plugs in and the car runs really well again. #thanks for all your help and kids, don't mix spark different plug leads!
Now, I think I'm up for some bigger injectors.

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Hilarious story... I was driving along today and the damn thing died again. Dang, what's wrong with it now! Wouldn't restart.

 

I had the laptop with me doing some tuning. Spent 10 minutes looking up the datalog. Couldn't find anything that told me what was wrong but I could hear the fuel pump working and the ECU was working fine. It had to be ignition related but I was floored.

 

So I finally lifted the bonnet, the plug from the coil packs had come loose.

 

I had to laugh. 😆

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Had the car out a few times recently. I'm currently working on installing new injectors (380cc up from 215cc) and an idle valve. I also need to sort out accel enrichment, but I think it needs more injector for that.

 

Today's little challenge is temp gauge related. I had to replaced my old L18 temp sender because it started leakly. The sender is hooked up to the stock flat dash. The ECU has a separate temp sender. The problem being the gauge is now reading a lot hotter than it used to. What you're seeing here is 88degC. When the motor hits 93degC (fans switching on), it's just nudging the red. Any thoughts on how to bring the gauge back into a more normal range?

IMG_20211209_124753_037.jpg

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man this thing is legit efi on an old engine is so cool loving it... idea for temp gauge wonder if you can find some kind of adjustable led dimmable resistor like this ... https://www.amazon.com/12V-24V-Dimming-Controller-Adjustable-Brightness/dp/B07NHJYYL7/ref=asc_df_B07NHJYYL7/?tag=hyprod-20&linkCode=df0&hvadid=366343882692&hvpos=&hvnetw=g&hvrand=10655307956302108566&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029598&hvtargid=pla-807030513961&psc=1&tag=&ref=&adgrpid=76503872296&hvpone=&hvptwo=&hvadid=366343882692&hvpos=&hvnetw=g&hvrand=10655307956302108566&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029598&hvtargid=pla-807030513961

 and just wire it inline and adjust it till you get the reading you got before the temp sender swap? ha ha... the right thing to do would be get a different sender but just an idea if that's not an option. 

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3 hours ago, sick620 said:

man this thing is legit efi on an old engine is so cool loving it... idea for temp gauge wonder if you can find some kind of adjustable led dimmable resistor like this ... https://www.amazon.com/12V-24V-Dimming-Controller-Adjustable-Brightness/dp/B07NHJYYL7/ref=asc_df_B07NHJYYL7/?tag=hyprod-20&linkCode=df0&hvadid=366343882692&hvpos=&hvnetw=g&hvrand=10655307956302108566&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029598&hvtargid=pla-807030513961&psc=1&tag=&ref=&adgrpid=76503872296&hvpone=&hvptwo=&hvadid=366343882692&hvpos=&hvnetw=g&hvrand=10655307956302108566&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029598&hvtargid=pla-807030513961

 and just wire it inline and adjust it till you get the reading you got before the temp sender swap? ha ha... the right thing to do would be get a different sender but just an idea if that's not an option. 

 

I wondered about that. How much resistance you'd need would be hard to ascertain. Worth trying though. Thanks! 

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There was an article written in the Dime Quarterly "magazine" that told you exactly how to test and determine the amount of resistance to put in to adjust that temp gauge.  Those are all hosted online now, though I couldn't tell you which edition to look in.  Hopefully the are searchable or someone can tell you better.  Otherwise you will have to do some looking.

 

Here is a link to them:   http://dimequarterly.blogspot.com/p/back-issues-ordering.html

 

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I've had a really successful couple of days tuning the motor. I changed the stock buick v6, 208cc injectors over to L67, 380cc injectors. I found a really good video on acceleration enrichment. Between the two, the car is running really well. Today I had Stuart Wilkins have a quick look at the motor. He gave me some tips about helping make more power. I also had him listen to it. I  was concerned about pinging at light load but he said it was fine. In January, I'll have him dyno tune it.

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  • 2 weeks later...

Today's efforts are in aid of another issue I've been having. Ie. fuel pressure. I've got the rail set to 45psi, but when I get down to half a tank, it's dropping to 35psi. Obviously, this might lead to running the motor lean. Thankfully the megasquirt is using the AFR table and the Wideband to stop that (I hope). The issue is I've connected the return line to factory tank return, which drops fuel into the top of the tank. The fuel dropping back into the tank is causing aeration and lower fuel pressure. So I've got to change the return line to run into the fuel pot on the bottom of the tank. Ironically, I called a buddy to pick his brain about this very issue and he's having the same problem on his rally car. He was able to diagnose my issue in 5 seconds flat. Nice, but I wish I'd done it this was in the first place. Typical really. 🙄

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