Holley Sniper EFI and RobbMC Surge Tank, 351c and FMX

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Robsweden

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Nice piece of solid mechanic for the KD Rob!

Ah I bet you went passenger side, because of the direction of the sending unit nipple forcing a loop if you would go old line route...

I hesitated do same thing and opted for the "all on one side", tho also means more complex bracket work as you can't fit

the 2 filters+pump in the safe space left over and it need be well encapsulated from the elements. so second filter is now relocated near wheel before entering bay.

I wished I opted for the other side at times :D

I'll post final picts of the whole line work when I finally will be able turn that key on.

How does your lines enter engine bay from the sides or you went back to tunnel? As you have inverted sides for the unit ports, where do they cross each other?

Also for you positive wire where did you tab the power? found the red green wire at ignition on column that would do, but wonder if there not another place

to do it, saving me the gym to solder the splice safely on the spot.

Hi Fabrice

This is how the hoses are routed, the pass eachother in a cross behind the sniper unit. Both hoses runs in protective flex hose when the pass critical areas. The return hose was to short so I had to put a 90 degree angle AN fitting. I bought the master kit with evrything included, it says enough hose . Thats not true, I had to buy new hose for the return line.

Some pics









I Went on the passenger side for getting a straight line under where the fuel pump is located. The outlet from the tank is bent upwards, so I had to make a slight loop to bring it back to the filter and pump. Not fancy att all but it seems to work fine. Il see if I can get a better Picture from under the car.

Regards Rob
 

Fabrice

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"The outlet from the tank is bent upwards, so I had to make a slight loop to bring it back to the filter and pump"

Yeah, they did not think about that setup back in 71-73 for sure :)

" I bought the master kit with evrything included, it says enough hose . Thats not true, I had to buy new hose for the return line."

I'm an old monkey, so mailed Holley to tell them I wasn't happy about that. They agreed and sent me a new 20ft line free of charge.

But the f...ers at UPS did not read the sending document clearly saying in big fat red font: "free of charge, transport and item payed" and counted me taxes on value of the product and transport. So waiting for the official invoice to dispute and try get what they stole from me back. Always same with UPS, it's an unfriendly company and it goes wrong 1 on 2 sending I get from them.

Where did you connect/splice the positive wire?

 

Robsweden

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Thats UPS , I Always tries to avoid them when shipping things to sweden.

The splice is in the back of the shocktower passanger side. I Also unconnetced all wiring not needed.

The wire from the unit to the handheld monitor goes direct in thru the center hole in the firewall. I spliced the wire from the MSD unit at the tachometer input so it goes out to the main harness along with the crank/ignition Cable. That was connected to the key ignition direct. The wire to the fuelpump, goes along with the fuel line on the passanger side, its protected by a nylontube. Ground Connection for the pump is taken from a bolt in the back.

Later on when it will Control timing also , il just cut the wire to the tachometer and use the White wire from the MSD box.



imageupload



image upload

Regards Rob

 

NewAgeMuscle

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An issue I am currently having with the car is that at light acceleration, the car is making a constant stream of muffled pops (not conventional backfire loud) right around 2000 rpm. The car idles well, accelerates well at WOT and doesn't seem low on power. However, when these pops are occurring I do feel some engine hesitation it feels like. Any ideas? Others I have talked to believe it could be running lean, but my AFR seems to be right sitting at a solid 13.5 at these times.
Where is your timing when this happens? I would richen it to 12.8 to 13.0 and see what happens. The other cylinder bank may be running leaner.
Turns out the opposite is happening. The popping went away for a bit and the car was running with around a 13.8-14.3 AFR while cruising at the 2000 rpm range. However, the popping came back and I noticed the AFR was dropping way down to around 12 at a cruise so I guess I'm running way rich! Not sure why this is happening, as the cruise AFR is set up by holley to run at 14, so theoretically the Sniper should be correcting itself no?

 

Don C

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I would check the connections to the oxygen sensor, make sure it is tight, and maybe remove it to make sure it's clean. The ECU may just think it's rich and is trying to lean it out. Something is causing it to change values.

 

Fabrice

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Finally done! So to be complete for those thinking about adding EFI (saw this post is way beyond 3k views),

Here's the extra stuffs work done since my last post in this thread.

First redid the previous casing for the pump, to improve the angle so the hoses would go around wheel nicely aligned.



The bracket second part add strength, and isolate protect the pump/contacts from wheel side.

As a side note after install, I can say, that the provided pump is very quiet. Installed this way, you can hear it

bits on first load, then no more.



Because the rubber fuel lines provided in kit (Earl's Vapors guard) are not ment to take 90 deg turns

I made a plate that holds the 2 lines from underneath the car and hold the last filter (there is not enough room at the tank

going this side of the car for the second filter). It's a bracket that required lots of checks/measurements to ensure lines

are near of car floor. (Still need do a splash cover for it when i'll get some time)



From there, it then goes to the unit. Spoiled the car (again) with some braided lines.

(make sure the hood hinge can close without touching the lines and that they will fit under the big engine brackets before drill @15mm for the @14mm radius connectors)



Then done another bracket to hold the monitor inside the car. I've mixed the provided one and aluminum.

Note that the plastic casing is rotated to allow it to glided in or out without a problem, yet be firmly held in place with no vibs.



Other details done, safety is important to me, so made another bracket in trunk for an inertia switch. 40 euros new,

but can be purchased at junkyard for 10, as suggested on this site by a member.

Also, for the feed line (the pink wire), if you splice at ignition the green/red wire, you want a good and safe connection for years to come.

remember that the ignition wire is THE wire in your car :) So I thought I share the way the splice was soldered for a secure connection.

I'm sure its not the nicest soldering ever, but I'm sure if the car let me down, it won't be that wire!

may sounds like a detail, but seen enough message on EFI probs that were caused by faulty connections.



If you go with the Holley kit, the 20ft hose is really not enough, having 2 sets of 20fts also allows you to air clean the hoses, and have them sealed

at ends during work from rear to front of the car, so you certain you have no debris entering them. You will need a few metal screws to hold your clamps

securely and about 16 clamps. These aren't provided either.

Then after all this work, aside a starter that broke on me the moment supreme and weird ignition probs after that,

you get this :)


For the next EFI, prolly my 429, now that I know bits more,

I will not use rubber lines whole way, but will instead use/make metal lines from back wheel to engine bay.

And if tank is still ok, I will make the connection for the return line in tank myself, unless I can find a cheap/used sending unit,

it's just a circular plate with a tube welded to it that you need, nothing more.

 
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Fabrice

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Thx Rob,

Its just the way I've installed it. I wish i'd seen similar post before I started. Hence why I wanted post these final picts.

The way you did (a fuel line per side to go around the angle issue) is also a nice & smart alternative!

Not to mention your nice KD construction...

 
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Robsweden

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Thx Rob,

Its just the way I've installed it. I wish i'd seen similar post before I started. Hence why I wanted post these final picts.

The way you did (a fuel line per side to go around the angle issue) is also a nice & smart alternative!

Not to mention your nice KD construction...
Thanks FabriceThe guy at the dyno looked at the kd for a while and smiled and then aha ... I see

Skickat från min SM-G955F via Tapatalk

 

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