Albemarle 24 - EFI maps and fuel return

[firstrodeo]

(First, apologies for the cross-post with thehulltruth - so busy there, its hard to get attention)

The quadrajet carb on the GM 5.7 liter in our '86 Albe needs a rebuild. Looking at the Holley Sniper drop-in replacement. Seems doable and reasonable in cost, but I have 2 questions:

1. Has anyone successfully plumbed a return line to the Albe tank without removal, etc.? I'm not even sure there's a sender unit we can remove and operate on.

2. Does anyone have a good (and safe) map for the Sniper quadrajet TB that will work with this engine? My thought is we'd run open-loop, at least initially.

 

[Scott Danforth]

first, welcome aboard

second, OEM engine installations do not return fuel back to the main tank. they have an engine mounted fuel module. I would suggest you set up something like this.

 

[firstrodeo]

first, welcome aboard

second, OEM engine installations do not return fuel back to the main tank. they have an engine mounted fuel module. I would suggest you set up something like this.

Scott - thanks!

Great to be here...

Yes, I know there's no return with the current setup. That's why I was asking if anyone else has done this already (installed a return) and without tank removal + surgery - that's a non-starter.

When you say, "set up something like this", what were you referring to?

Thanks again.

 

[alldodge]

If the current tank does not have a fitting which can be used for the return, can install a Tee fitting on the fill hose.
https://www.hardin-marine.com/p-16582-fuel-line-return-to-tank-adapter.aspx

They also make a fitting which you drill a 1/2 inch hole in the fuel tank and then install fitting. The fitting flares it on the inside so no leaks.

Use a hand drill or a fan blowing a lot of air when drilling. The steel bit will not spark on an aluminum tank the the drill will be sparking on the brushes

https://www.performanceonline.com/fuel-tank-return-line-bung-kit-universal/

 

[matt167]

Keep in mind that the Holley Sniper IS USCG rated, but also that a wide band oxygen sensor needed for self learning will not survive.. Holley's software will have a tune close enough to make it run, but you will never dial it in

 

[firstrodeo]

Keep in mind that the Holley Sniper IS USCG rated, but also that a wide band oxygen sensor needed for self learning will not survive.. Holley's software will have a tune close enough to make it run, but you will never dial it in

Assuming I can find a spacer block with an O2 sensor port to install under the riser elbow, won't the sensor last long enough to get a reasonable tune? When it dies, it's an easy swap, right?

 

[matt167]

Assuming I can find a spacer block with an O2 sensor port to install under the riser elbow, won't the sensor last long enough to get a reasonable tune? When it dies, it's an easy swap, right?

The spacer block ( you can drill a spark plug anti fouler fwiw ) will help the oxygen sensor live, but it's also going to skew the reading into being leaner than it should be . Your talking about sensors that are north of $50 being wide band

 

[alldodge]

Once the Sniper is tuned the O2 can be removed

 

[matt167]

Once the Sniper is tuned the O2 can be removed

Right, because it runs in open loop. Getting a sensor to live long enough might be a challange..

 

[Scott Danforth]

I personally would spend the $40 on a rebuild kit vs $1500 for a complete sniper kit

 

[alldodge]

Right, because it runs in open loop. Getting a sensor to live long enough might be a challange..

Don't need 10 but can use something like this
https://www.ebay.com/itm/10X-O2-Oxy...n-spacer-HHO-02-Bung-CEL-FIX-US-/312936153612

Agree carb kit would be easier

 

[matt167]

Don't need 10 but can use something like this
https://www.ebay.com/itm/10X-O2-Oxy...n-spacer-HHO-02-Bung-CEL-FIX-US-/312936153612

Agree carb kit would be easier

A spark plugs anti fouler from the parts store drilled out does the same thing.

 

[firstrodeo]

Been traveling, finally got out to boat today.

Opened deck plate to look at fuel tank pickup/sender area. Saw this:



Left is fuel line. It goes from here to filter/water-separator, then mechanical pump on engine block, then quadrajet.

On the right looks to be an extra port welded into the tank? With a plug in it? I'm going to call Albemarle on Monday to verify, but if what I am thinking is right, I may have a good fuel return option.

 

[firstrodeo]

Right, because it runs in open loop. Getting a sensor to live long enough might be a challange..

Explain - because of the sensor not being mounted on a downward angle?

 

[matt167]

Explain - because of the sensor not being mounted on a downward angle?

Water is hard on the sensors. A blown head gasket in a car can take them out from the steam

 

[firstrodeo]

As for spacer block to mount the sensor, this looks right:

https://www.ebay.com/itm/322489476520

As for the mounting angle thing - if the O2 sensor tapped hole is pointed toward the bow, I think the sensor tip will be angled downward most of the time, so liquid should not accumulate.