Installing a Holley Sniper on a 3.5 v8

RBBailey

NAS-ROW Addict
Callsign: KF7KFZ
The stool was made by a couple awesome German dudes, one is a paleontologist and the other is a builder, but they are friends and metal working hobbyists. I obtained some old doors and removed the skins, they cut them up and fabbed the stool. www.aero-1946.com

Now I know I won't be selling my old doors when I find a new set.
 

Defender425

Member
So the first hurdle seems to be getting the proper blanking plugs to eliminate the air injection, “detox” in some terms or “pulsar” as River called it. The ones Kip mentioned above are also available in the US from The Wedge Shop:


...but I’m pretty sure these are not correct. They appear to be for engines that have four air pipes per manifold, but this engine has three. Plus Famous Four wanted 26 UKP shipping for their plugs. I think this application may require the ETC6474 but these UK suppliers aren’t really good on this small onesie-twosie stuff.

Maybe a hydraulic shop will have something or worst case, I’ll pull the fittings and have them capped off. If I find a cheap set of newer manifolds I might just swap them even though it sucks to remove old manifolds.

View attachment 13042
I used I belive a metric plug when I did my heads a few months ago. Local Ace hardware had them. Installed with some sealant and good to go. You are never going to use them again so buggering the threads is a good thing to help retain them.
 

Defender425

Member
Coolant line routing is something that needs to be figured each time for these conversions. Different motors have different configurations and parts get replaced over the years so you might not even be looking at stock parts depending on what sort of life your truck led.

This vehicle had the heater return tube running under the manifold and the feed from the pump going directly into a hose fitting by the thermostat housing/water neck. This fitting is not present on Edelbrock manifolds but the thermostat housing has a blanked off section that covers a hole in the new manifold. My first inclination is to have that section drilled out to install a hose fitting.

The coolant pipe fits under the manifold just fine, but drilling and tapping to create mounting locations is not an option since there is no metal where the mounting tabs are. I’m mullong a couple different options.

The coolant temp sensor and vacuum fitting transferred right over, but as others have noted the threads in the manifold need dressing up, they are rough with excess swarf.View attachment 13169
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Only way to do it is either drill and tap that housing and install a barbed fitting or pay about $75-100 and get the housing for a 101 FWD control. I dont have the part # on hand right now. Don't get the similar one that also tips forward a bit as it will not allow much if any dist adjustment.
 

LRover

Member
I drilled and tapped the the thermostat housing and ran the heater tube along the right side of the manifold when I installed my 4bbl manifold. I am following this with interest as I am wanting to go with a sniper eventually to replace the carb. My 110 is also ex-Swiss
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JimC

Super Moderator
Staff member
Can you snap a pic of the drilled/tapped housing please? the bung I’m looking at only measures 20mm across, that’s not a lot of room for threads...
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LRover

Member
Yeah, I remember that I had to be careful about the drilling and tapping. The "Made in China" fitting worked well. Sorry I can't remember the fitting size but you get the idea. I was able to reuse some hoses. I can snap a pic of it on the engine in the daylight if that will help.

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JimC

Super Moderator
Staff member
Actually, that’s perfect. Thanks. I found the 101 Forward control part, 613762, but it just looks like the part I have with a hole drilled in it. I did find the correct gasket too, part number 610387 In stock at most places for 69 cents.
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Defender425

Member
Actually, that’s perfect. Thanks. I found the 101 Forward control part, 613762, but it just looks like the part I have with a hole drilled in it. I did find the correct gasket too, part number 610387 In stock at most places for 69 cents.View attachment 13268
That is the one. The orginal one you have the spud is too short for a hose, needs a fitting. The FC housing needs a plug in the top spud too. I'd take a chance and try installing a fitting first.
 

JimC

Super Moderator
Staff member
Jim:
Are you installing a fuel pressure gauge?

I hadn’t gotten that far yet. id like to avoid permanently mounting one in the cabin but recognize I’m going to have to figure out something to test and verify that the system works.
 

RDavisinVA

Technical Excellence Contributor
Holley recommends a fuel pressure gauge .
If you call for tech support the first question is "what's the fuel pressure?" and when the answer is "I don't know", tech support can't do much to help.
We mount a fuel pressure gauge on all vehicles with Sniper EFI.
 

RDavisinVA

Technical Excellence Contributor
There is a pressure regulator valve, but if it is not set properly, the Sniper won't operate correctly.
There is not a built in pressure transducer to provide a pressure reading for a gauge, it has to have a separate external sender.
 

JimC

Super Moderator
Staff member
Then it sounds like I’m installing a pressure gauge. Rob D - is there somewhere here where you’ve shared the part/setup that you use?
 

Roverman2010

Well-known member
There is a pressure regulator valve, but if it is not set properly, the Sniper won't operate correctly.
There is not a built in pressure transducer to provide a pressure reading for a gauge, it has to have a separate external sender.
Surely a design flaw?
 
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