Our 78 Newport gets a Sniper. WiP though

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Ok, I pulled the trigger on the Sniper EFI. Was deciding between the Holley and Edelbrock products. Went with the former because of the cost.

Unlike fellow Calgarian Angus66, I aimed at a more complicated scope: engine stays in, all new ignition with time control, the fuel pump in the tank.
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The fuel tank, lines and the TB part are done, put the distributor in. "While there", fixed a tired drive shaft U-joint, replaced original rear shocks (still shockingly capable considering the age) and did a bit of anti-corrosion touch-ups.

Even though I pulled the radiator and the fan out, I am still on the fence over replacing the timing sproket and chain. Even though it is 100% original (nylon?), it shows 0 slack. Think I get to it once I have the EFI running, over next winter, when I finally get to install the maxxjax lift.

Removing the fuel tank was so far the most physically challenging part. The original owner did not know or trust threaded fasteners, so the towhitch, handcrafted from the 8-10 mm steel (some 25 kilos or more) was welded in. Cutting the damn thing out to drop the tank I said many nasty things about the poor fella. Hope he's already long gone and his karma did not suffer.
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But I digress. Once all done, I plan to do a writeup so that an amateur like me could have some second thoughts before following the same path. There are certain obstacles to overcome.

For now though, I am struggling with the electrics (which I am not very good with and the ambiguity of Holley manuals and videos not helping much).

Aside from the ignition setup (magnetic pick up distributor with the coil driver wiring), I need to get switched ignition (+) for the coil and some other stuff. The wiring is sort of stock (except Lean Burn was removed eons ago). There are no emission controls (I only see PCV and the heat riser flap).
Any suggestions? I do have the 2-tome shop manual with schematics, so if someone could point out at a proper page/part of circuit - much appreciated.

Also, Sniper manual calls for 15 degrees BTDC when setting the distributor, but if I read the specs on the Canadian 400 big block correctly, it should be 20 degrees for the basic setup. I plan to call Holley tech support with this, but some second opinions are very much welcome as well.
 
Sweet thread.. I’ll live through you vicariously as I, some day, wanna do this to my 77 NYB.. anxiously awaiting your updates. :rolleyes:
 
Damn welded on hitches! I've dealt with those too, no fun. The worst was the '71 Polara parts car I bought. It had a full skid plate covering the tank welded on! I've been wanting to do what you are doing too! And will definitely be taking notes.

Is the original + coil wire not switched? I'm not familiar with formals, fuselages have two extra spaces on the fuse box, one switched, one constant.

And if the sniper asks for 15°, and Chrysler asks for 20°, start at 17°-18°, and tune from there. A few degrees isn't going to hurt anything.

Concerning your timing chain, it should be fine as long as you keep your RPM's down. I actually had an original fail on me driving back to Edmonton from Calgary years ago. Drove down no problem, averaging 80 mph, bought a car, stayed longer than I should have. On the way back, brought the average up to 90 mph, and on a straight, wide open road, decided to let her stretch her legs. After about two minutes of 110 mph, that chain skipped and left me stranded. Of course it was 1:00 A.M!, so much for getting home "early". I guess that's what I get for speeding!

Should mention that was a 1971 383, with 113,000 miles.
 
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The original coil should get it's power from the ballast resistor, this will have switched power on the other side of the resistor
 
To feed the efi brain juice during both crank and run you need to tie into the blue and brown wires at the ballast, if the colors are the same on formals. The ballast is where power is consolidated for both key positions
 
The orig ELB timing was "base + computer". Are you setting the Sniper to do similar? Key thing is that it starts easily and quickly. Might start with 15 degrees and see how it runs. Increase a bit to see how it acts and runs. If no "spark clatter" on acceleration, whatever works. If the system uses a Knock sensor, might edge up to 20 and see how it goes.

Keep us posted,
CBODY67
 
Is the original + coil wire not switched? I'm not familiar with formals, fuselages have two extra spaces on the fuse box, one switched, one constant.
And if the sniper asks for 15°, and Chrysler asks for 20°, start at 17°-18°, and tune from there. A few degrees isn't going to hurt anything.
Concerning your timing chain, it should be fine as long as you keep your RPM's down.

Like someone else suggested down in the comments, one of the wires to the resistor module is the one I need.
I thought of going this "kinda in the middle" route, but having near-zero experience with older than 90s vehicles, wanted some second opinion.
We are not racing or anything, never ran above 120-130-ish (in kmh) and do not plan to.
 
The orig ELB timing was "base + computer". Are you setting the Sniper to do similar?
If the system uses a Knock sensor, might edge up to 20 and see how it go

No knock sensor there.
I hope I interpret this thing correctly (Canadian 400 C-Body, Line 6 counting from bottom up):

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To feed the efi brain juice during both crank and run you need to tie into the blue and brown wires at the ballast, if the colors are the same on formals. The ballast is where power is consolidated for both key positions
This! Thank you!
 
Ok, so the project is complete. After putting some 300 trouble-free kms with Sniper I guess I can call it success.
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So here is some summary on the technicalities and the whole "is it worth it" question.
I will start with the latter.

Worth it - Yay or Nay?
If you are only looking to improve drivability for you summer toy - then firm "NO". Just get yourself a new carb, new wires, ensure there are no air/vac leaks and enjoy your car. The extra expenditure, time and effort simply not worth it.

If you are driven by the desire for better drivability, as well as long range / all weather predictability and superior throttle response - and are prepared to put some 2K into the project - YES, by all means. But also be aware that once you get used to the new set of dynamics, you will want more - sharper and tighter steering, sportier cam, TC with higher stall speed... And did I mention tighter steering?..

How complicated?
If you can rebuild and tune your engine with closed eyes, habitually swap distributors, cams and at least once installed and set up some software or a mobile app - it's a walk in the park. Just RTFM and be prepared to look for extra info on the interwebs.
If you are like me - familiar with modern plug and play cars and comfortable with general wrenching, some aspects will be a bit of a challenge. And here it greatly depends how you approach it - as a mental excersise to keep you grey matter humming or a nuisance that postpones immediate gratifications.

What do you need?
There are at least 2 setups, as I see it.
Basic - you just buy the injector kit with external fuel pump and whatnots, but leave the ignition as is. Worth doing if your ignition has been updated (and not a mess of old hacked wires left from the Lean Burn delete surgery performed 30+ years ago).
All in (that is how I did it) - the injector kit + magnetic distrib, wires, coil/coil driver, in-tank fuel pump... Or any combination of these components, really.

You also need decent set of tools, good wire crimpers, rolls of wires and connectors, million zip-ties, lots of gorilla tape, fuel hose and or copper-nickel pipes, a timing light, and ability to control the hate of imperial units: as someone from the metric universe I totally struggle with all these gages, thread designations, and how to measure up the wrenches - whereas it is immediately clear if 11 mm is less than 13 or 15, with all these x/8 and x/16 it just bends my mind backwards every time.

What not to like?
How the information from the OEM is presented. I realize, that it is mostly aimed at the "experienced" category and serves as nothing more than a general guidance. As a tech writer who spent quite a few years in MFG creating shop assembly and repair manuals for complicated drilling machinery, I'd say a more systematic presentation would be much welcome and make it so much easier for a layman like myself to install and tune it. What especially annoys is that once you start digging, you drown in endless linking to yet another write-up or a video that only confuses you more. Web forum on Holley's own website is not too bad, but the advice from Holley folks is not always very informative and more often than not is a copy-paste of the same set of endless links to writeups that have some more links to click...

As to what I did - see next post which will probably take a bit to write.
 
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Sooo... The install is complete and after some further tinkering (invoilving second U-Joint, adjusted front bearings and a pair of front shocks) I got it running the way I expected it to. Well, almost, as I still have to battle the drivetrain vibration at 65-70mph and higher. I dunno if this is perfect, good or otherwise, but decent to my eye and ear as long as I stay below 70. Will happily show around to locals.
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Great post! Looking forward to you next thread to explain your installation with all it’s challenges and victories.

javier
 
Great post! Looking forward to you next thread to explain your installation with all it’s challenges and victories.

javier
I kinda tried to man up and put the pen to paper, so to speak. But it will be way too difficult and time consuming to do a complete write-up. It is easier if someone interested just posts a specific question.
To me (starting with near-zero knowledge of and past experience with carburatored engines and the 70-s technology), the biggest/most time-consuming aspects have been (lined up from most to least difficult):
- collecting all installation/setup info from multiple sources from Holley, Youtube and forums to get a concise picture specifically for our engine.
- mating car electrics (mangled on mine) with Sniper electrics + ignition setup
- figuring out location and orientation of the in-tank fuel pump assembly with related gas lines connections.
- final tuning.
- (tongue-in-cheeky) SAE fasteners and wrench sizes.
 
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