fuel filter, regulator question

[shadango]

I need some fuel system advice.

My wiring harness is out of the car right now being gone over so I am lookin gat other stuff during the down time.

When I first got my car the previous owner had a fuel filter installed down near the frame rail, before the pump.  I had done a thread back then asking about that and some folks advised I should move it to AFTER the pump, others said they run theirs that way.

Well, after watching the fuel  go thru the filter where its at right now (clear fuel filter) I saw a alot of bubbles etc.....looking around on line it seems that the general advice is always run the filter AFTER a mechanical pump as they push better than pull....plus, with the filter before the pump, a negative pressure situation is built up or somesuch....causing the bubbles and fuel delivery issues.

SO I decided to change the location.

Ah, but its not that simple....LOL

I have, inline after the pump, a fuel pressure regualator and gauge....then a short run of hose to the edelbrock carb (3/8" inlet).



Now, I was planning on just cutting the hose and adding it between the regulator and the carb (where my hand is)  BUT, in the holley instructions they show the filter after the pump but BEFORE the reguator....    ....The way I am set up right now that cannot happen as you can see.....

So, the question -- can I run the fuel filter AFTER the regulator or is that asking for issues too?  Is the holley regulator that you guys recommended then.

Also, anyone know where I can get a clear 3/8" nippled fuel filter? All I can find is the steel cased ones.....I like the clear ones so you can see the fuel flowing in the event of an issue....I was looking at those spectre glass filters, but someone posted a pic of one on this forum and was told they are junk...so I didnt want to go that route.....Had one on a car 20 years ago and had leakage issues too so I am avoiding that kind though they look cool.

Thanks folks
***********************
update  9:10 pm

Well I decided to go for it and see what happens...LOL

[Chryco Psycho]

you have a filter in the tanl already so only extremely fine particles could get that far , I would say you are just fine the way you plumbed it

[shadango]

Thanks CP....

Do you think the filter affects the pressure at all? In other words, if I set the regulator at 6 lbs, will there be 6 lbs at the carb or is the filter going to knock it down some??

I am also still wondering whether that filter and the regulator are acting like big heat sinks and contributing to my long cranking at hot restart......but not a lot of choice on how to run them at this point.

Do you have any ideas on the clear filter question?

The carb has a 3/8" nipple, so that is the size I used on the regulator.....what would happen if I went to 5/16" nipples so I could use the clear filter?  Or am I better off with the 3/8" setup?   the line from the tank is only 5/16".

[Supercuda]

I would be more concerned about the 5/16" fittings causing a restriction, than the filter itself. There is a 3/8" clear filter out there, but I haven't looked for one in a long time. Your hot-restart cranking issue is more likely caused by heat-soak of the carburetor itself. Smallblocks rarely make enough heat in the engine bay to move the problem to another source. The fuel boils away, and leaves the bowls empty, or nearly so. The result is a long crank time, sometimes with symptoms of flooding, sometimes with symptoms of no fuel. Either way, it is easily controlled with a insulating spacer. Phenolc resin, or wood, in a 4-hole spacer, will likely work best. I have had excellent results with just a 1/2" thickness spacer. This should also sharpen throttle response, and might give you an extra 500 RPM up top.

[shadango]

I would be more concerned about the 5/16" fittings causing a restriction, than the filter itself. There is a 3/8" clear filter out there, but I haven't looked for one in a long time. Your hot-restart cranking issue is more likely caused by heat-soak of the carburetor itself. Smallblocks rarely make enough heat in the engine bay to move the problem to another source. The fuel boils away, and leaves the bowls empty, or nearly so. The result is a long crank time, sometimes with symptoms of flooding, sometimes with symptoms of no fuel. Either way, it is easily controlled with a insulating spacer. Phenolc resin, or wood, in a 4-hole spacer, will likely work best. I have had excellent results with just a 1/2" thickness spacer. This should also sharpen throttle response, and might give you an extra 500 RPM up top.

I wasnt concerned about the smaller filter restricting anything....I was wondering if changing the hose AND the filter as well as the carb fitting to 5/16" was an issue, seeing that the hose/pipe from the tank to the pump is only 5/16".

Thanks for the feedback on the hot start issue....I did try adding a spacer.....I will have to check the size, but I think it is the 1/2" size, and still have the issue bigtime....as far as material, I thought its was a "phenolic" type.....I wonder if I would do better with the wood or going thicker?  Another issue I have to watch is how much clearance I have under the hood.....

I do know that I can do a hot restart real easy if I do it within a few minutes of having shut down.....after 5 minutes or so is when I have issues.....so it does still seem like the fuel is boiling away.

************Update  11:29 am

Ok, found an old thread I posted a pic in last year...here is the spacer I am using....



Its not a phenolic plastic or wood....its some other material.

I am thinking maybe trying a wood one.....have to see what clearance I have....not sure I can run a 1".....

I have this manifold --



So I think the divided one (not the 4 hole) is what I need, right?   

Summit/Jegs only lists a 1/2" divided wood spacer



so ordered that at summit.

Should I use the current one I have on top of that I guess?   

[Chryco Psycho]

It is a fair amount of work but your heat cross over under the intake is open , , I would remove the intake & block the heat cross over port with a peice cut out of the old gasket & re-install the intake , you could go to the RPM Air gap intake to further reduce manifold heat , I have found the alum reflector plates under the carb can haelp a lot as well

[ntstlgl1970]

If you are going to block the heat crossover, there is also a lifter valley baffle (to keep hot oil off the bottom of the intake) available from milodon that you could put on while the manifold is off. I think it is relatively inexpensive, or you could make your own.

[shadango]

These are good suggestions fer sher.

Not gonna pull the manifol;d quite yet.........i ordered the wood gasket (who would have thought....a WOOD car part !)...will try that first since its an easy install (I hope that is)......if I still have the issue I guess this will be the next step.

[Supercuda]

The shield, as Chryco suggests, is also a good idea for heat-soak issues. I recommended the 4-hole spacer due to its "isolation" effect upon the venturii of the carb. It will increase throttle response, and allow a leaner idle calibration. The slotted design will not have as positive an effect. Like the open design, it will only increase plenum volume, and isolate the carb from heat. The combination of a shield and a spacer is acceptable for serious cases. The isolator gasket that you pictured is a factory-style piece, although it does not appear to be aluminum or asbestos (both used in factory applications), which will limit its efficacy. Some aspects of the old technology really did work better. The other ideas for keeping the heat down are also excellent, and commonly used on smallblocks. I found that using a 4-hole spacer, on top of enough open spacer height to put the carb above the plenum divider (about 1/4" is enough), the high-rpm effect is very good. You get to "fool" the intake into thinking it's an open plenum, wthout sacrificing any throttle response.

[shadango]

Thanks...I didnt know if you knew what carb I had and whether that would affect the setup or not.....figured maybe you thought I had factory carb and thats why you were suggesting the 4 hole deal.

Well, I will try the one I have for now and see if it helps with heat soaking....

I *think* I may have seen an example of the aluminum pan you guys were talking about at the parts meet today but I didnt know if it was the right one or not so passed.....

[mopar12372]

youll be just fine with the filter setup , if the tank sock is good you dont need the filter at the carb. what you did is good insurance though. the spacer is giid to have too with a mechanicle pump to prevent vapor lock.you are going a great job and doing it right for your setup.

[shadango]

Nothing can be easy I guess.   

Two issues --

Trying to fit the (new) 1/2" wood laminate spacer.......

First issue, but temporarily solved -- the spacer brings the height of the carb up far enough that with my 14"x3" K&N filter it hits the hood. So I swapped in my old 2" tall, 9" air filter setup.....just makes it if I use a wing nut and not the fancy schmancy edelbrock air cleaner hold-down nut.

Second, and yet unsolved issue -- The divided gasket I have is the type shown here...

http://www.jegs.com/i/Edelbrock/350/9266/10002/-1



It is too thick as it is a very thick doubled-up deal (actually two gaskets sandwiched and then riveted together) meant to help prevent fuel boiling...it is .320 thick.....

What I need is a plain old gasket, in the divided configuration but I cant find them anywhere....Edelbrock doesnt show them on their site nor does Summit or Jegs as far as I can see.  A standard thickness gasket will work if I can find one.  I have a standard square bore gasket but its not divided and I was told that I have to have the divided type for my dual plane manifold.

Any ideas? I was thinking of going to the parts store and buying gasket material and trying to make one....but not sure if what they sell will work...

 

[shadango]

Ok....I have it figgered out.

I went down to autozone and found that mr gasket makes a 4 hole gasket that , after doing a little trimming, does exactly what I needed.



Here is the "heat insulating gasket" from Edelbrock I was using.....




As you can see it is a pretty thick gasket, but the wood one is almost twice the thickness and made of wood.  I am hoping it helps.

I had to go back to my small air cleaner to make this spacer work on my car (flat hood)...it just barely clears.



Not real happy about that...it has a 3/8" drop base....I guess I could go with a 2" tall element but then that would ecrease the amount of space inside....between the top of the carb and the air filter lid....that would be bad, right?

The smaller element is a 9"x2" deal.....I had switched to the 14"x3" K&N to get more air.

 
So to date I have changed the location of the fuel filter and added this spacer.  If I still have hot start issues, I guess the next step will be one of Chryco's suggestions....block the heat riser passges or maybe go to an air gap.....

Does the air gap sit higher than the manifold I have?  I am guessing it has to by design.....so that may not be doable with my hood.

[dodj]

Hey, your ecu and regulator are upside down.

[Supercuda]

The most important thing about using low-profile air cleaners is that you must keep enough space between the top of the carb and the bottom of the air cleaner lid to prevent fuel siphoning, and also allow sufficient airflow to make some power. As for the gaskets, the most important thing to remember is that you don't want to suck any gasket into the intake. Matching the holes in your spacer, or at the top of te intake, are secondary concerns. Using the divided gasket on top of the spacer, and an open one below, is acceptable. As I said before, the late-model thick gaskets are not as good as the original ones, and are a compromise, at best. The heat shield you would want, is going to look like a big flat shield, maybe with cutouts for linkage. It will have either an open or 4-hole area in the middle, for the carb. I recommend mounting it below the spacer you have, to keep the heat away.