Spin-on fuel filter build for 3.2

[Discseven]

Project started with doing no more than replacing old fuel lines in engine bay. Noodled a filter direction and simple approach... gone. Hot air blower will be removed and open mounts on manifold put to use for filter head. First sketch above. Car's '80 with '85 3.2. Daily.






Side view. Flat mount-plate on manifold as well as bridge-filling open gap between intake's rubber elbow and filter head is idea. Plan = match back-slope of intake's rubber elbow with perf'd aluminum bridge. Need manifold in hand now to see if this works but am waiting to disable car.








Fuel entry variations.




Credit to Jim, aka “Fanaudical,” for creating CAD files. Appreciate your collaboration on this project Jim! You going extra mile in thought & digital draw is brilliant stuff---thank you.

Plan was to CNC out of 6061 aluminum. Jim's suggested it's possible to achieve desired smooth satin finish with 3D metal print. Next, is on me to proof measurement files from Jim. Then on to seeing where CNC & 3D lead.

At no time am I saying/implying my way being the way to do anything. Am taking a path among the infinite.

.

[sugarwood]

Pardon the dumb question, but what is the point of this ?
What problem are you trying to solve?

[Discseven]

^^^ Sugar... no problem here. Point/purpose is to dive in for the creative challenge and odd satisfaction to be had from going through the build process. Is it pointless? Surly to some it will be. I happen to like this... so I do it. And I thread it because some will enjoy it.

[john walker's workshop]

A modified MFI console would work.

[911pcars]

A few ideas here:
https://www.google.com/search?q=remote+fuel+pump+and+mount&safe=active&sxsrf=ACYBGNT5USbtCu6QUO6VCJfpQ-A3QFequw:1580586434107&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiX_cOnj7HnAhVYoZ4KHaxdAJEQ_AUoAnoECA0QB A&biw=2004&bih=1092

[Discseven]

Originally Posted by john walker's workshop

A modified MFI console would work.

Originally Posted by 911pcars

A few ideas here:
https://www.google.com/search?q=remote+fuel+pump+and+mount&safe=active&sxsrf=ACYBGNT5USbtCu6QUO6VCJfpQ-A3QFequw:1580586434107&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiX_cOnj7HnAhVYoZ4KHaxdAJEQ_AUoAnoECA0QB A&biw=2004&bih=1092

I did invest much time looking through consoles guys. Everything found is designed relatively the same---exposed plumbing enters & exits sides or top. That's fine, functional design. But what happens if plumbing is hidden? Am inclined to think result has a cleaner look. Not that clean is better or worse than anything, is personal pref to hide plumbing in this case.

...That said, exposed plumbing can be fine art---I've seen instances on PPF and elsewhere where guys have done amazing plumb-works. Hats off to those guys & projects.

.

[911pcars]

If plumbing is not exposed, it's not visible nor possibly accessible for inspection and service. Suggest hiding the plumbing behind a removable panel or door. FWIW, tidy plumbing (and electrical bits) is nice to see.

Sherwood

[Quickstep192]

I liked the idea of a spin on filter as well. I liked the idea of more filter media area and the convenience of easier filter changing. I adapted a marine filter which also provides water separation.

My car was an MFI car converted to Weber’s and the filter head has plenty of inputs and outputs for the supply, return and separate lines to both banks of carbs and a place for the pressure gauge.

[shadowjack1]

Originally Posted by Quickstep192

I liked the idea of a spin on filter as well. I liked the idea of more filter media area and the convenience of easier filter changing. I adapted a marine filter which also provides water separation.

My car was an MFI car converted to Weber’s and the filter head has plenty of inputs and outputs for the supply, return and separate lines to both banks of carbs and a place for the pressure gauge.

This is sweet.

[Discseven]

Originally Posted by 911pcars

If plumbing is not exposed, it's not visible nor possibly accessible for inspection and service. Suggest hiding the plumbing behind a removable panel or door. FWIW, tidy plumbing (and electrical bits) is nice to see.

Sherwood

Yeah... inspection is good point Sherwood. That did plague me for a while. More complex design--than is on table now--allowed for some inspection. Moved away from that on basis: IF connections are all done with good hardware & great care, and, once set up, system is pressure tested to PSI well beyond op standard, THEN there should be no reason for system failure. (Of course this does not guarantee zero-failure but am inclined to work towards that. I've seen a Porsche of mine on fuel-fire. Getting this build right is only option.)

On your flag, makes sense to look in on system with endo to make sure all's in order. Thanks. Believe all connections planned can be reached by hand (but not seen without endo or mirror.)
.

[Discseven]

Originally Posted by Quickstep192

I liked the idea of a spin on filter as well. I liked the idea of more filter media area and the convenience of easier filter changing. I adapted a marine filter which also provides water separation.

My car was an MFI car converted to Weber’s and the filter head has plenty of inputs and outputs for the supply, return and separate lines to both banks of carbs and a place for the pressure gauge.

Marine adaptation for water sep is great idea QuickS. Think you picked nice location given your webbers. Am curious what PSI webber fuel system operates?
.

[Quickstep192]

Originally Posted by Discseven

Marine adaptation for water sep is great idea QuickS. Think you picked nice location given your webbers. Am curious what PSI webber fuel system operates?
.

I think the operating pressure is between 3.5 and 4. If you take a close look on the right side of the filter head, you can see there’s a small needle valve that regulates how much the return is restricted which in turn regulates the pressure to the carbs.

[Quickstep192]

Here’s a closer picture.

[Discseven]

Originally Posted by Quickstep192

I think the operating pressure is between 3.5 and 4. If you take a close look on the right side of the filter head, you can see there’s a small needle valve that regulates how much the return is restricted which in turn regulates the pressure to the carbs.

Thanks for PSI info QuickS.

[Discseven]

Tony, aka “boyt911sc , and Bill Johnson, aka “Mr. Injector”... thank you guys for Motronic chats. Is your fault I've gained smarts---humbly said---to get into this fuel stuff. Tony... you're welcome to send some of your titanic energy my way any time, COD.

Filtered thinking...







Hengst or Koblenschmidt filters... first choices. Butts, neither company I spoke with was inclined to provide micron & flow specs. Would have been nice to include German filter but agonized over that detail long enough. Came down to Fram, Donaldson (best at providing specs,) and a NAPA Gold. Compared, am calling Fram best quality---for materials, build & finishing. 10 micron. Didn't get flow specs for Fram but compared it to Donaldson. Would estimate Fram being slightly better than Donaldson's 25 g/ph. Is plenty for 3.2 stock injector flow (24 lbs/ph wide open throttle /6 = 4 g/ph max per Bill J.) Designed filter head mainly for Fram P4102A. Hopefully Fram won't discontinue that model. Donaldson fits as backup. Trick with Donaldson is it has internal rubber diaphragm that filter-head post must pass through or raw fuel can bypass filter. Just discovered 30mm post (below) is too short to reach through diaphragm. Deal with that should need arise.




Toughest part to get so far: M16 x 1.5 x 30 with full threading and smooth bore. Took a month... to come from Shanghai. (Patience seems to magically come with age.)






Using blower mounts on manifold to mount filter head. Parts are no-brainer to pull. New block-off plate---with no holes---took some time to sort hole placement.




Longer and shorter fuel runs. Long run puts fuel tubing near but below rails. Would then zip injector cables to tube instead of rails. Minor cleanup. (Shorter run is just that... shorter. Don't see any benefit.) Also looking to clean space below manifold with new run.

What of pressure regulator and dampener? Do these go bad? Can they be tested? ???






Fuel hub is coming from 1 1/2” aluminum rod. Compression fittings are for some junctions...




… Cones & receivers will connect new fuel lines to car's existing ends. These fittings forced stainless tubing instead of aluminum. Not happy with that but is what it is---Unless someone has way to solder/braze/weld steel to aluminum tube.

.

[winders]

This is what I am putting in my race car:



That module to the right is a fuel pressure/temperature sensor. It has a built-in delta pressure indicator to let you know when the filter needs changing.

Bosch provides a specification for protection of electronic fuel injectors, which is a minimum capture efficiency of 87% at 5 microns, and 100% capture efficiency at 35 microns. This filter setup beats that.

[Discseven]

^^ Scott... I like that one---consider it top spin-on canister design. Among other features you mention, lock is very nice touch.
.

[Discseven]

CNC by Xometry. Excellent online order system IMHO. Thanks again Jim, aka "Fanaudical", for creating CAD files for this.







Am making slow progress due to life getting in way.

.

[Discseven]

Fuel in out: bores | tap = 29/64" | 1/2" 20 NF




Filt post bore | tap = 37/64" | m16 x 1.5 D6




Post = m16 x 1.5 x 30 mm




Fram P4102A first fitting.

[chrisbalich]

This is a super cool project. I just installed a canister fuel filter for similar reasoning.
I'm having difficulty envisioning where this assembly will mount in the engine bay tho.