What I did on my Datsun today

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Randalla
Posts: 710
Joined: Fri May 24, 2019 8:58 am
Location: North Scottsdale

Re: What I did on my Datsun today

Post by Randalla »

I also did Duffman's mod, but in my case it turned out the issue was hatch seals, taillight gaskets, and carb adjustments.
1967 1/2 Roadster- 1600 4 cyl.
1972 240Z- 280 I-6
1975 280Z SCARAB- 350 V-8
1975 280Z - I-6
1977 620 King Cab - L18 4 cyl.
2003 350Z Track- VQ V-6
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SCARZME
Posts: 93
Joined: Sun Aug 04, 2019 11:13 am
Location: Payson

Re: What I did on my Datsun today

Post by SCARZME »

An update to my EFI upgrade on the Scarab:
On my first real shakedown run up to Star Valley for breakfast the car ran great. On the way home though it just quit and had to coast into the Chevron station at the edge of town. Did the quick checks and found no spark. Called a friend to come pick me up, loaded the car on my trailer and rolled it into the garage where it had to sit for a couple weeks while I completed installing laminate flooring in the back bedroom (two more rooms to go.)
When I completed that honey-do I did some more troubleshooting and found there was spark coming from the MSD to the coil but no signal from the EFI to the MSD. Called Holley tech support, they said send it in, sounds like a component failure.
Well, they called me back and said they were sending a new unit rather than repairing. Cool!
In the meantime I removed the seats, rewired everything to do with the EFI to minimize RFI and EMI: move MSD from under passenger seat to driver footwell, moved Safeguard from passenger footwell to driver footwell, rerouted vacuum line for Safeguard from the Alky MAF to the boost controller. Now all power wires are thru one firewall hole, the signal wires are thru another hole and the coil wires are thru a third hole. Lemme tell ya, I'm getting too old to be spending hours on my back under a dashboard!
Got the new Sniper Thursday, installed Friday, fired up today on the first turn of the key. WHOO-HOO! Took a quick lap around the neighborhood. Now, fingers crossed there's no more component failures during burn-in.
Solvang here we come!
Bob - Payson
72 240Z
74 260Z Turbo-Scarab
71 510 Wagon (project)
67 Roadster VG30 swap (sold)
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Randalla
Posts: 710
Joined: Fri May 24, 2019 8:58 am
Location: North Scottsdale

Re: What I did on my Datsun today

Post by Randalla »

No more component failures!!! Sounds like you made some good progress while waiting though, Bob. Did you mean no more failures during "burn in" or "burn out"? :lol: See you next weekend in Solvang.
1967 1/2 Roadster- 1600 4 cyl.
1972 240Z- 280 I-6
1975 280Z SCARAB- 350 V-8
1975 280Z - I-6
1977 620 King Cab - L18 4 cyl.
2003 350Z Track- VQ V-6
theAngryMarmot
Posts: 96
Joined: Sat May 25, 2019 9:10 pm

Re: What I did on my Datsun today

Post by theAngryMarmot »

SCARZME wrote: Sat Apr 23, 2022 5:49 pm . Called Holley tech support, they said send it in, sounds like a component failure.
Well, they called me back and said they were sending a new unit rather than repairing. Cool!
to minimize RFI and EMI:
Holley support is pretty awesome usually.

I have installed dozens of their Sniper / Terminator EFI units and it is amazing how sensitive they can be to EMI/RFI. I think the shape of the engine bay actually comes into play too - I had installed a Sniper setup on a '37 Chevy Hot-Rod Truck with a 350SBC in it - and I did my usual due-diligence on making sure nothing was ran near the coil, spark plug wires, alternator, starter, and that the power/ground were ran to the battery - however I was still getting symptoms that were the same as RF/EM interference. I ended up buying a set of near-field probes for my oscilloscope and had several hot-spots that didn't make sense. My best theory is that the narrow trapezoidal shape and the domed hood were basically focusing/concentrating the EM/RF interference and causing the issues. I ended up using some shielded wire, shielded spark plug wires, and lining the underside of the hood with RM/EM absorbing material from a company called TrueSpec (probably overkill, but oh well.) Solved the issue, ran great afterwards.

I did quite a few custom Terminator setups and always ordered additional shielded sensor wiring harness kits from Holley for cam/crank sensors. Also, the Holley EFIs really hate magnetic sensor based distributors. Issues may not manifest themselves for several hundred miles - but they will start cropping up with a magnetic sensor distributor. If you are running the typical SBC MSD distributor with the magnetic pickup (Street-Fire, Pro-Billet, Ready to Run, etc) then I would seriously consider going to one of the holley branded sniper hall effect distributors - even more so if you are going to allow the ECU to control timing. The most annoying part is when they first came out with their systems, they didn't realize the issues the magnetic sensors cause - and had instructions pertaining to wiring them up. Later, they dropped that from the manuals and added the "we don't recommend using magnetic pick-up distributors" disclaimers. I think I had installed 6 or 8 of them at that point - all using the customers existing very common MSD distributors.

The Holley systems are IMO the best, I have installed many FiTechs and similar and had QC issues.
dat521
Posts: 142
Joined: Sun May 26, 2019 11:53 pm
Location: laveen

Re: What I did on my Datsun today

Post by dat521 »

installed new water pump, 7 blade fan, pulley, radiator and shroud and fuel pump on my 521
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Randalla
Posts: 710
Joined: Fri May 24, 2019 8:58 am
Location: North Scottsdale

Re: What I did on my Datsun today

Post by Randalla »

Doing the same on my 620. Have to figure out how to separate the fan clutch and pulley from the water pump. Appears that it is pressed on and though the water pump is junk, I don't want to damage the clutch and pulley.
1967 1/2 Roadster- 1600 4 cyl.
1972 240Z- 280 I-6
1975 280Z SCARAB- 350 V-8
1975 280Z - I-6
1977 620 King Cab - L18 4 cyl.
2003 350Z Track- VQ V-6
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