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charley norton
06-27-2005, 01:36 PM
Has anyone had a problem with gas getting too hot before it enters the carb? I have a glass filter and thought it was just air bubbles until someone smarter told me the gas was litterally boiling. There is no heat shield between the exhaust manifold and the fuel line as it leaves the pump. Am I missing a heat shield? What should I do?

Thanks, Charley

63 R2 Avanti

JDP
06-27-2005, 02:45 PM
There is not a heat sheild, and modern gas will boil off much easier than the old stuff.

Studebaker On The Net http://stude.com
64 R2 4 speed Challenger (Plain Wrapper)
63 R2 4 speed GT Hawk
55 Speedster
50 2R 10 truck

charley norton
06-27-2005, 03:04 PM
JDP, You think it would be worth rerouting the line? Or then winding it in a coil? I've heard of that being done.
Charley

63 R2 Avanti

Sonny
06-27-2005, 03:06 PM
quote:Originally posted by charley norton

Has anyone had a problem with gas getting too hot before it enters the carb? I have a glass filter and thought it was just air bubbles until someone smarter told me the gas was litterally boiling. There is no heat shield between the exhaust manifold and the fuel line as it leaves the pump. Am I missing a heat shield? What should I do?

Thanks, Charley

63 R2 Avanti


Heck yeah, you can believe that it boils off Charlie. I've seen it with my own eyes, and exactly as you've described! I put a piece of rubber fuel hose, (sliced lengthwise), around the fuel line from the pump to the in-line filter on my V8 Lark. I also put a piece of aluminum foil around the area from the fuel pump, up to just behind the power steering pump, and I use the diesel fuel trick to keep the boiling and vapor lock problems down. It seems like my car really likes the gas/diesel combination.

One other VERY important thing that can be done, (although it takes time and a few bucks), is to buy an electric choke replacement cap and block off that damn crossover passage that goes through the intake manifold from the heat riser, or at least get a thick paper gasket for under the carb.. That in-line filter sits right above the oven created by the intake manifold too. Just put your hand on an unblocked intake after a short trip, on a hot day, if you need assurance as to why the carb should be insulated from the intake. Then you'll know what your poor carb. has to deal with....

This "new" fuel looks/smells/acts Nothing like real gasoline. It's pure additives and pure garbage.....

Sonny
http://RacingStudebakers.com

Sonny
06-27-2005, 03:12 PM
quote:Originally posted by charley norton

JDP, You think it would be worth rerouting the line? Or then winding it in a coil? I've heard of that being done.
Charley

63 R2 Avanti


I don't think it would help Charlie. There's a LOT of heat under the hoods of our Studebakers, and really no place for it to exit. The coil trick is great if you coil it in a coffee can and put ice in the can, but I think a coiled fuel line, in such a hot engine compartment, will just make the problem worse.

Sonny
http://RacingStudebakers.com

charley norton
06-27-2005, 04:31 PM
Yea,Sonny your right about the heat. I often wonder if my temp. guage is right after I open the hood and feel the heat. I ordered a new carb base gasket from Jon Meyers and a new flapper valve. Maybe I'll think of something. I like the "hose over pipe"idea of yours but I'm a little afraid of using diesel in my fuel after seeing how many filters new diesel trucks use

63 R2 Avanti

big jim
06-27-2005, 06:23 PM
i had no idea so many had THAT problem. I dont on my r-2 avanti, course i use 103 low lead av gas... dont think that makes any difference.

Mike
06-27-2005, 06:41 PM
The R2 engines were supposed to need less intake manifold heat than other Stude engines. There was a special, R2, drivers side intake manifold gasket with most of the heat riser passage blocked. This reduced flow through through the intake, and heat. The intake gaskets may have been replaced with standard versions - wide open on both sides.
Ted Harbit said he had gaskets blocked or restricted.
The fuel return line is supposed to help keep the gas from boiling. Are you sure yours isn't plugged?
Mike M.

curt
06-27-2005, 08:36 PM
Modern cars have a fuel pump in the gas tank. This is how they keep fuel from vaperizing, gas under pressure from the tank foward is under presure and has a higher tolerance for heat. Is this boiling gas under pressure from the mechanical pump, if so forget what I said. Does it only boil when very hot? Like is it air? Does car stall?

Sonny
06-27-2005, 08:43 PM
quote:Originally posted by charley norton

Yea,Sonny your right about the heat. I often wonder if my temp. guage is right after I open the hood and feel the heat. I ordered a new carb base gasket from Jon Meyers and a new flapper valve. Maybe I'll think of something. I like the "hose over pipe"idea of yours but I'm a little afraid of using diesel in my fuel after seeing how many filters new diesel trucks use

63 R2 Avanti


Trust me, your car will love the diesel, just one gallon per fillup will be good. In fact, if I fill mine up with a quarter tank or less, I still put a gallon in, (that's the size of the little can I have).

Both of my diesels have only one filter, a large filter, but just one. Diesels need filtration much superior to the gas powered engines due only to the fact that diesels are injected. As long as you're getting the diesel from a clean station, it's as clean as gasoline Charlie.

Sonny
http://RacingStudebakers.com

65cruiser
06-28-2005, 06:52 AM
Sonny,

Tell me about this diesel thing. Exactly what is the purpose?

________________________
Mark Anderson
http://home.alltel.net/anderm
1965 Studebaker Cruiser

Chris Pile
06-28-2005, 10:27 AM
Sonny -wouldn't you agree that "clean station" does NOT include convenience stores? Here in Kansas they are not required to clean their underground tanks yearly if their fuel sales are less than half of their fiscal total. I only buy fuel from name brand stations that meet the State requirements, don't you? test

Sonny
06-28-2005, 01:37 PM
quote:Originally posted by 65cruiser

Sonny,

Tell me about this diesel thing. Exactly what is the purpose?

________________________
Mark Anderson
http://home.alltel.net/anderm
1965 Studebaker Cruiser


Without trying to bore you to death with a long explanation about fuels, (diesel vs. gasoline), Mark, suffice to say that the main difference between diesel and gasoline fuels is actually very simple, it's how each engine is combusted. Specifically, it has to do with the molecular weight of each fuel, (they are different, diesel is higher), diesel has a higher boiling point and is formulated to reduce knocking, (diesel engines run a two to three times higher compression ratio).

Although some may not agree, by any relative comparison of anything/everything concerning the internal combustion engine, the diesel engine is superior in nearly every aspect/category to any gasoline engine ever built. Simply because of the nature of the beast, you just can't go wrong by applying anthing that you can apply to your gasoline engine that was engineered for a diesel.

Now before anyone jumps my butt for saying that :), I want to state here and now that I LOVE the gasoline engine too! [^] But, being an engineer, being practical, and as an owner of a couple of diesels, I do have to say that I wish another of Studebaker's "firsts" would have been to install a diesel engine as the standard offering. I honestly think that you're gonna see a lot more diesels in new cars, light AND heavy trucks running on propane or natural gas to meet the fuel emission standards that Uncle Sugar has planned for us in the near future.

Hope that I answered your question.


Sonny
http://RacingStudebakers.com

Sonny
06-28-2005, 02:05 PM
quote:Originally posted by Chris Pile

Sonny -wouldn't you agree that "clean station" does NOT include convenience stores? Here in Kansas they are not required to clean their underground tanks yearly if their fuel sales are less than half of their fiscal total. I only buy fuel from name brand stations that meet the State requirements, don't you?


Absolutely Chris! In fact, a couple of things that I consider when Iím buying fuel...

One, Look for a station that has the fuel tanks above ground. We even have them here in ol' Yew Nork! I drive about 12 miles to a place that has them and have never, ever had a problem with bad fuels.

Two, NEVER put fuel in your vehicle when you see the fuel truck dropping fuel! Since fuels float, tanks that are in-ground have a lot of water in them! Yep, it's practical AND legal. Every fuel tank, above or below ground has an amount of moisture in it, at least due to condensation. The reason for more water in a below ground tank is, if you were to take all of the liquid out of an underground tank it could/would pop out of the ground. Fuel is drawn from the tank via a "stand pipe", with the inlet of the stand pipe, (supposed to be), placed in an area of the tank that has only fuel. SO, if you get fuel when the fuel truck is dropping fuel into that tank, stirring all the water up, you may be in for an unpleasant surprise.

Three, Fuel tanks are supposed to be "stuck" with alarming regularity. Meaning that the attendant should be putting a chemical onto a long stick/device that is put down into the bottom of the tank to measure the amount of water in that tank. The chemical turns a different color when it comes in contact with water, thereby indicating the level of water. A "good" station does it at LEAST daily. Don't be afraid to ask if/when your favorite station performs this ritual. If I get a blank stare, I'm out'a there! ;)


Sonny
http://RacingStudebakers.com

Sonny
06-28-2005, 02:54 PM
quote:Originally posted by curt

Modern cars have a fuel pump in the gas tank. This is how they keep fuel from vaperizing, gas under pressure from the tank foward is under presure and has a higher tolerance for heat. Is this boiling gas under pressure from the mechanical pump, if so forget what I said. Does it only boil when very hot? Like is it air? Does car stall?


Yepper, I think you're exactly right Curt, a good electric or a high performance mechanical pump system is the only way to go. A good, solid fuel flow being necessary to avoid vaporizing. You got me thinkin' about how different our old Studebakers and new cars really are. Hell, new cars are all injected, the in-tank fuel pumps put out around 30 or more psi and all new cars use a fuel bypass system, cooler fuel is constantly available and circulating from the tank.

Our old mechanical pumps only supply fuel at about 4-5 psi, and the new fuels are much less "heavy" as earlier fuels were. Kinda like the difference between drinking a Coke and a milkshake, our old mechanical units were designed for a different product, (let alone the fact that the new fuels eat 'em up internally).

The other real problem is the heat of our Studebaker intakes, no water cooling them, just hot exhaust gasses heating them, (heat riser open or closed). Want a real shock? With just the old mechanical pump installed, take a look at your see through, inline fuel filter before you start your car, cold. Is the filter full? It should be at least half full. Now drive the car, get it well into the operating temp range, pop the hood with it running and look at the filter. Empty? Yep, that's what I've seen with all my old cars. That means the vacuum of the carburetor HAS to, hell it IS, drawing the fuel in that's keeping the engine running! As long as the conditions are good you're fine, put any extra heat into the formula, (a parade, long idle, etc.), and voila, stutter, stammer, quit..... BTDT too many times myself.

I've just totally given up on our old, mechanical pumps. Every Studebaker I have on the road gets a new, integrated filter, electric fuel pump. Can't beat 'em? Apply their technology! [:p]


Sonny
http://RacingStudebakers.com

casey
06-28-2005, 03:55 PM
Sonny- can you recommend a good electric fuel pump/filter combo for the Stude V8? Do you have it run as soon as the key is in 'on' position? And where do you mount it on the car?

charley norton
06-28-2005, 04:51 PM
Curt- Gas boils in the glass filter I have between the mech pump and carb. Itis noticeable when I shut the engine off after it has been warmed up. My main concern is safety(I don't want to have a fire). The fuel line is factory, so I guess it's where Studebaker thought it should be. But it comes out of the pump and passes within an inch of the exhaust manifold. Jon Meyer told me the opening in the fitting of the return line needs to be no more than .040 in Diam.. I'm going to check that next chance, although that sure seems like a small hole.

63 R2 Avanti

Sonny
06-28-2005, 06:48 PM
quote:Originally posted by casey

Sonny- can you recommend a good electric fuel pump/filter combo for the Stude V8? Do you have it run as soon as the key is in 'on' position? And where do you mount it on the car?


As a matter of fact I can Casey. The last one I bought last week was an E8012S, Master was the brand name, from Auto Zone. I like it best because it has a smaller, screw-on metal filter on it, instead of the filter that's integrated into the housing like the one I bought before it. I don't have the bill right in front of me, but I believe it was something like $39.95.

The way I wired mine in the Lark is, (was in a hurry), I have a straight wire from an accessory fuse block that I added to the car, when I turn the key on, the pump is on. I have to get off my butt and wire it the right way, through an oil presssure sending unit/brake light switch, (screwed into the oil pressure port in the head), like I did on the '50 and my dually Ford.

When it's wired in through a pressure switch, I used a 30 amp, spring loaded, "prime button" under the dash on those vehicles, (get a good button/switch as that pump draws a good amount of current). IF I need it, I can push the prime button before stsrt and it remains powered as long as you have oil pressure.

Glad that you asked about mounting it. On a Lark, you have to be careful of the exhaust system. The gas line goes up the passenger side and the tail pipe has a pretty healthy "crook" in it there, just in front of the R/H, front corner of the tank. It's pretty close there in stock configuration anyway so you might even want to use the "rubber-fuel-line-around-the-metal-fuel-line-for-insulation", trick.

I mounted mine right in the "dog leg", (just where the frame starts up, over/around the rear axle on the R/H side). Anywhere in there is fine, just remember to keep it as close to the tank as you can, watch the routing and heat from the tail pipe. I did use a metal line from the tank to the inlet of the pump. That means you'll have two short pieces of rubber fuel line hose in that line, one at the tank, one at the pump. Push the metal lines together tightly inside that piece of rubber fuel hose so that the ends touch, you'll minimize leaks and the amount of rubber exposed to the new type fuel, (which tends to break rubber fuel hose down faster).

Lemme know how it goes for ya Casey.

Sonny
http://RacingStudebakers.com

DEEPNHOCK
06-28-2005, 06:48 PM
Casey,
You 'should' run the electric fuel pump with a separate on off switch, AND wire it in with a low oil pressure switch. This way you can shut it off if you want, and it will shut off if the engine stalls out for some reason. This is a safety issue.
(And I can speak on this after once running back and forth between 4 corner service stations and blowing all ALL of the fire extinguishers to put out a fuel fire being fed by an electric fuel pump. Saved the guys truck, but the bill for everything was over $4k....in 1980)
Jeff[8D]




quote:Originally posted by casey

Sonny- can you recommend a good electric fuel pump/filter combo for the Stude V8? Do you have it run as soon as the key is in 'on' position? And where do you mount it on the car?


DEEPNHOCK at Cox.net
'37 Coupe Express
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'61 Hawk
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DEEPNHOCK
06-28-2005, 06:50 PM
Wow Sonny... That seems like a lot.
I just fill all my old oil bottles with diesel and dump one in per fill up. Stops the ping, and I haven't had vapor lock since I started doing that. And the bottles are easy and neat to travel with....
Jeff[8D]



quote:Originally posted by Sonny


quote:Originally posted by charley norton

Yea,Sonny your right about the heat. I often wonder if my temp. guage is right after I open the hood and feel the heat. I ordered a new carb base gasket from Jon Meyers and a new flapper valve. Maybe I'll think of something. I like the "hose over pipe"idea of yours but I'm a little afraid of using diesel in my fuel after seeing how many filters new diesel trucks use

63 R2 Avanti


Trust me, your car will love the diesel, just one gallon per fillup will be good. In fact, if I fill mine up with a quarter tank or less, I still put a gallon in, (that's the size of the little can I have).

Both of my diesels have only one filter, a large filter, but just one. Diesels need filtration much superior to the gas powered engines due only to the fact that diesels are injected. As long as you're getting the diesel from a clean station, it's as clean as gasoline Charlie.

Sonny
http://RacingStudebakers.com


DEEPNHOCK at Cox.net
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Sonny
06-28-2005, 07:38 PM
quote:Originally posted by DEEPNHOCK

Wow Sonny... That seems like a lot.
I just fill all my old oil bottles with diesel and dump one in per fill up. Stops the ping, and I haven't had vapor lock since I started doing that. And the bottles are easy and neat to travel with....
Jeff[8D]

DEEPNHOCK at Cox.net
'37 Coupe Express
'37 Coupe Express Trailer
'61 Hawk
http://community.webshots.com/user/deepnhock


quote:Originally posted by Sonny

Trust me, your car will love the diesel, just one gallon per fillup will be good. In fact, if I fill mine up with a quarter tank or less, I still put a gallon in, (that's the size of the little can I have).

Both of my diesels have only one filter, a large filter, but just one. Diesels need filtration much superior to the gas powered engines due only to the fact that diesels are injected. As long as you're getting the diesel from a clean station, it's as clean as gasoline Charlie.

Sonny
http://RacingStudebakers.com


I gotta admit, putting diesel in old, used oil bottles sounds like a much better idea Jeffster! (Leave it to a cheap-as-, 'er, frugal Stude guy to think of that one:D) I do use a gallon with a fillup, (Lark tank is 18 gallons). I was worried about it smoking when I first started using diesel, but it doesn't and I can tell when I don't put diesel in it. It seems to actually effect performance, (for the better), when I use diesel. I'm gonna try your oil bottle trick and per your recommendation, might even try to wean it down to just two bottles next time. ;)

The reason I really don't worry about using a tad too much diesel, (excess smoke is the worse thing that can happen), is because of another great feature of diesel fuel, it provides MUCH more lubricity to the upper end of the engine than gasoline does. Man-o-man, I love that stuff! :D[8D][^]






Sonny
http://RacingStudebakers.com

DEEPNHOCK
06-28-2005, 08:44 PM
I suppose you could use as much as possible until it either started smoking, of fouls the plugs. I only use one because I am a cheap sob[:0]
Jeff[8D]



Sonny
http://RacingStudebakers.com
[/quote]
I gotta admit, putting diesel in old, used oil bottles sounds like a much better idea Jeffster! (Leave it to a cheap-as-, 'er, frugal Stude guy to think of that one:D) I do use a gallon with a fillup, (Lark tank is 18 gallons). I was worried about it smoking when I first started using diesel, but it doesn't and I can tell when I don't put diesel in it. It seems to actually effect performance, (for the better), when I use diesel. I'm gonna try your oil bottle trick and per your recommendation, might even try to wean it down to just two bottles next time. ;)
The reason I really don't worry about using a tad too much diesel, (excess smoke is the worse thing that can happen), is because of another great feature of diesel fuel, it provides MUCH more lubricity to the upper end of the engine than gasoline does. Man-o-man, I love that stuff! :D[8D][^]
Sonny
http://RacingStudebakers.com
[/quote]

DEEPNHOCK at Cox.net
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curt
06-28-2005, 10:26 PM
Deepnhock, could this disel fuel carbon up the engine enough to burn a valve? I do not know. A PHd chemist told me a pint of diesel fuel to a tank of gas would lower the vaporization point in the gas enough to prevent 'knock' and vapor lock. I have never tried one gal to a tank of gas.

curt
06-28-2005, 10:28 PM
As long as the boiling gas has zero air(oxygen) it will not ignite.

Sonny
06-28-2005, 10:53 PM
quote:Originally posted by curt

Deepnhock, could this disel fuel carbon up the engine enough to burn a valve? I do not know. A PHd chemist told me a pint of diesel fuel to a tank of gas would lower the vaporization point in the gas enough to prevent 'knock' and vapor lock. I have never tried one gal to a tank of gas.


A pint? Whew, mebbe I AM using a tad too much diesel in the mix! [:p] Honest, I have never seen/had any problem while using the diesel in the 18 to 1 ratio. Like I mentioned, my car seems to actually like the stuff, seems to run better! It REALLY worked pretty well on my '49, 6 cylinder. I can't imagine that it could carbon up a valve in that ratio, (18 to 1), especially if the valve train was relatively "healthy". It might foul plugs and smoke like hell if ya use too much, (I can tell you from experience that a '57 Chebby can run on 18 to 1, diesel to gas, and run pretty damn good! :D:D), but I'm sure that you'd feel a difference in the performance.

Heck, If the PHD says a pint will do it, then by God, I'll just use one quart bottle, (more is always better right? [:p]).

Sonny
http://RacingStudebakers.com

charley norton
06-29-2005, 07:53 AM
Sonny-- In my search for octane booster a while back, I ran across a site talking about the use of toluene (found at a paint supply store). They said that it had an octane rating of 114. Use a gallon to a tank can boost 93 octane up to 97-98. They also said that the indy cars use around 80% tolulene in the mix and that it burns so cool (high flash point,I guess), that a line is run from the radiator to the tank to keep the fuel warm. Another guy had a formula where you use a gallon of tolulene and a certain amount of transmission fluid and mineral spirits(for detergent and lubricant). I didn't try this(and probably won't) but a cool fuel would help with the boiling gas problem. I am really starting to think after hearing that Big Jim used 103 octane and didn't have a problem (which is close to what I used last tank) that my problem may be in the return line. I had to replace the gas line due to rust. What would be the best way to test it.Do you think it would hurt anything to just blow it out from the pump side? My filter should catch whatever trash that may get in the tank

63 R2 Avanti

charley norton
06-29-2005, 08:01 AM
Here's a site that explains alot about octane booster and some specs. on gasoline. Pretty interesting stuff. If there is somebody who can give me a formula for lead additive, that would be great! Or maybe just a good deal.

http://www.team.net/sol/tech/octane_b.html

63 R2 Avanti

DEEPNHOCK
06-29-2005, 08:45 AM
I don't think you want to screw around with tetra0ethyl lead...
From what I know, it's pretty toxic....
More reading at:
http://www.chm.bris.ac.uk/motm/leadtet/leadh.htm
and
http://yarchive.net/chem/tetraethyl_lead.html
and
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12804524&dopt=Abstract
(important if you are an earthworm);)
and
http://www.manbir-online.com/diseases/lead.htm
(the most readable)
and to scare a donation out of you...
http://www.cancer.org/docroot/PED/content/PED_1_3X_Lead.asp?sitearea=PED&viewmode=print&
Jeff[8D]




quote:Originally posted by charley norton

Here's a site that explains alot about octane booster and some specs. on gasoline. Pretty interesting stuff. If there is somebody who can give me a formula for lead additive, that would be great! Or maybe just a good deal.

http://www.team.net/sol/tech/octane_b.html

63 R2 Avanti


DEEPNHOCK at Cox.net
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charley norton
06-29-2005, 12:01 PM
Doean't my car need lead additive, especially on long trips?

63 R2 Avanti

Sonny
06-29-2005, 02:35 PM
quote:Originally posted by charley norton

Sonny-- In my search for octane booster a while back, I ran across a site talking about the use of toluene (found at a paint supply store). They said that it had an octane rating of 114. Use a gallon to a tank can boost 93 octane up to 97-98. They also said that the indy cars use around 80% tolulene in the mix and that it burns so cool (high flash point,I guess), that a line is run from the radiator to the tank to keep the fuel warm. Another guy had a formula where you use a gallon of tolulene and a certain amount of transmission fluid and mineral spirits(for detergent and lubricant). I didn't try this(and probably won't) but a cool fuel would help with the boiling gas problem. I am really starting to think after hearing that Big Jim used 103 octane and didn't have a problem (which is close to what I used last tank) that my problem may be in the return line. I had to replace the gas line due to rust. What would be the best way to test it.Do you think it would hurt anything to just blow it out from the pump side? My filter should catch whatever trash that may get in the tank

63 R2 Avanti


Whew, I'm glad that you're probably not gonna mess around with mixing that cocktail of chemicals Charlie. It sounds like it can give impressive results though, and probably could be useful for the racing crowd, but it also sounds like a solid PITA to have to mess with it.

However, I think you may have struck on an important consideration. That return line is not just an open tube back to the tank, it must have a restrictor, (there is restriction in all fuel return systems, including diesel). What happens is, without the restrictor, the fuel takes the path of least resistance, effectively and dramatically lowering the fuel pressure at the carb. inlet. With a "healthy" fuel system, the carb actually draws fuel in, there is always a lower pressure area in the fuel bowls due to the vacuum effect of the intake. The engine will run but it's working hard, drawing fuel in from the line to keep running, and of course, performance suffers.

Obviously it's always better to push fuel into the carb., and it's very possible that you've removed/disturbed the restriction when you changed that line. I'm not familiar with the fuel return system on the Avanti and I don't know where the restriction is located, but I'm sure that the system employs some form of return restriction.

As far as blowing out the lines, start at the tank and work forward to the carb.. As much as possible, inspect the inside of the fuel lines as well. I've seen rust in fuel lines many, many times. Also, don't forget the fuel pump. Pull the fuel pump and open it up. If you've had a lot of contamination from the tank, you'll find a buildup of that crap inside the pump! When you blow out the fuel line, disconnect it at all connections, do not trust your filter to catch everything, some of that contamination is less than 3 microns, (a human hair is about 8 microns), you'll blow that stuff through the filter and could easily damage the filter using high pressure air.

Anyway, that's where I'd start Charlie, with that return fuel restriction and I'd be very interested in what you find.


Sonny
http://RacingStudebakers.com

Mike Van Veghten
06-29-2005, 02:58 PM
Interesting take on fuel line "returns".

There isn't a return line that has a restriction in "any" drag race setup (including mine) that I know of. And I know some guys that have some pretty fast cars. Both turbo charged and carbureted. Return lines are mostly -6 on carbureted and -8 on turbo powered engines.

If I miss read and you're talking about a restriction on the feed side...again, no one that I've ever seen has any restriction on the feed side of the system.

Either way, just use a smaller line, lower pressure pump, regulator (sort of a restriction, but "adjustable").
"No" restrictions in any fuel lines works best. Regulate the pressure as close to the carb. inlet as possible, that keeps the volume of fuel right on hand.

A restrictor in the "fuel system" or "air fuel inlet" (carb., manifold, head) or the "exhaustsystem", is a no, no for both power or mileage.

Sonny
06-29-2005, 05:07 PM
quote:Originally posted by Mike Van Veghten

Interesting take on fuel line "returns".

There isn't a return line that has a restriction in "any" drag race setup (including mine) that I know of. And I know some guys that have some pretty fast cars. Both turbo charged and carbureted. Return lines are mostly -6 on carbureted and -8 on turbo powered engines.

If I miss read and you're talking about a restriction on the feed side...again, no one that I've ever seen has any restriction on the feed side of the system.

Either way, just use a smaller line, lower pressure pump, regulator (sort of a restriction, but "adjustable").
"No" restrictions in any fuel lines works best. Regulate the pressure as close to the carb. inlet as possible, that keeps the volume of fuel right on hand.

A restrictor in the "fuel system" or "air fuel inlet" (carb., manifold, head) or the "exhaustsystem", is a no, no for both power or mileage.


Mebbe I just didn't explain myself very clearly Mike. :) Lemme try again... Unless regulated, never restriction in feed lines. Not only the flow, but the velocity of the fluid decreases at the point just after the restriction, definitely an undesirable effect in a feed line. Race cars and new fuel injected cars use much higher fuel pressures than do our Studebakers, loop back restriction in a low pressure system is always in the "tap" or return side, (be it a smaller line or a physical obstruction). We have about 5 psi available to work with.

Fluid dynamics are the purest example of Bernoulli's Principle. The Principle defines physical "laws" and are nearly absolute. I honestly donít wanna bore ya, but to explain it simply, a fuel system is subject to a number of factors, but specifically, pressure, as it relates to force, area, velocity, as well as mass and weight density. If you "tap", (introduce flow separation), into a fuel line, you also effect velocity, therefore in order to maintain working pressure at expected point of work, you must increase fuel pressure exponentially or reduce the amount of "tap" in order to maintain required amount/pressure at the head or work.

There must be some restriction in the "tap", (return line), in a low pressure fuel supply system in order for the system to work properly. Hell, it's the easiest and cheapest way to do it.

I think youíre thinking on the right track, but itís still like apples and oranges, weíre working with old technology, nothing like race cars and new injected systems. Now, if we slap a big, phat Ďol electric fuel pump and a fuel pressure regulator on that Avanti, Iím with you, problem solved! [^]

Hope that's a better explanation.


Sonny
http://RacingStudebakers.com

Mike
06-29-2005, 05:09 PM
Several people have mentioned the restriction in the return line on Avanti's. I didn't notice a restricted fitting on mine, when I had it apart. I'm using the early setup with the return from the fuel pump, as opposed to the later setup with the return from a glass bowl on top of the engine. Exactly which fitting is supposed to be restricted? Where is the restriction on the glass bowl versions?
Possibly, the size, (1/4"), of the return, and its length are enough of a restriction.
In the Dec. '63 Avanti parts book, the return line isn't pictured; but parts are listed for both versions. The "early" type is listed as "R3". The shop manual shows pictures of the early version.
Mike M.

Mike
06-29-2005, 05:31 PM
I've seen simple fuel injection systems that controlled mixture strength with a single restriction in the return line.
There was supposed to be enough flow in the Avanti return to actually cool the pump. On the early, or "R3" type, a .040" restriction in the return would quickly become blocked. The only filter is at the carburator. The pump and return aren't protected.
I'm not sure where the return takes off, in relation to the filter in the glass bowl, on the later version.
Mike M.

charley norton
06-29-2005, 07:37 PM
Mike and Sonny-- I have the early version as you describe it. The return line comes directly of the pump itself. The .040 measurement I quoted I got from Jon Meyer. He told me to watch out for R1 fuel pump conversions where there is a vent that needs to be plugged to use on an R2. And then told me to check the fitting on the pump for the return line and make sure that it had an opening no larger than .040. He went on to say that it was common for that fitting to be changed with one bought at a parts store that had an opening much larger. He was pretty adament that if the opening was too large, it would affect performance. As this car is original, and replacement pump I used I got from the previous owner of the car and was told it was NOS (I still rebuilt it), then I have to assume it has that little hole and very well may be plugged. Do you guys know Jon. He seems to know his stuff. But irreguardless of what the problem ends up being, I'm going to reroute the fuel line away from the exhaust manifold and hope it doesn't hurt the car being judged in a car show(not that anyone around here would know where it's supposed to be in the first place)
Charley

63 R2 Avanti

studegary
06-30-2005, 11:54 PM
Yes, Jon "knows his stuff."

DEEPNHOCK
07-03-2005, 05:35 PM
Wll, different cooks use different recipe's;)
I have used 1 quart diesel per 18 gallon fill up for years.
Never have fouled a plug, nor hurt any parts.
I have never burned a valve in a Studebaker.
But I have to admit... that it is not a cure all for everything.
Jeff[8D]




quote:Originally posted by curt

Deepnhock, could this disel fuel carbon up the engine enough to burn a valve? I do not know. A PHd chemist told me a pint of diesel fuel to a tank of gas would lower the vaporization point in the gas enough to prevent 'knock' and vapor lock. I have never tried one gal to a tank of gas.


DEEPNHOCK at Cox.net
'37 Coupe Express
'37 Coupe Express Trailer
'61 Hawk
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