PDA

View Full Version : Engine: Aluminum Intake & Vaporlock



JoeHall
08-23-2011, 08:33 PM
A question for the fortunate few that have them, does the aluminum intake reduce or eliminate vapor lock?
Thanks,
Joe

DEEPNHOCK
08-23-2011, 08:59 PM
No.
If the aluminum intake has the heat crossover passage in it, it will be affected just like a cast iron intake will.

Adding a heat insulator carb base gasket helps a lot.

Now, if you block open the heat riser valve (or gut it, or remove it), and then block the crossover passage in the intake (stainless steel plate(s) with a composite intake gasket...
Then you can help the issue somewhat.

Adding an electric fuel pump helps a lot.

Adding a quart of diesel fuel to a tankfull of gas helps some.

Adding a fuel line bypass return helps the most, but is the most involved to set it up.

PackardV8
08-23-2011, 09:10 PM
Agree with all Jeff's comments above, except:
Adding a quart of diesel fuel to a tankfull of gas helps some.Jeff and I will have to agree to disagree on this one. Petroleum engineers have convinced me nothing good comes of putting diesel in gasoline.

jack vines

Mike Van Veghten
08-23-2011, 09:10 PM
And an electric fuel pump eliminate it all together. Just pressurize the system.

Courious, how come, me, living in one of the hotter states in the US, have never had a vapor lock problem. Or am I overlooking something ?
And it isn't because I'm only 16 years old (almost 61)...!
My daily driver 259, Lark wagon does not have an electric fuel pump...

Mike

JoeHall
08-23-2011, 09:21 PM
I learned to deal with vaporlock over the years, and have applied most of the above suggestions; the collective sum of all of them helps quite a bit, but still does not eleminate it.

With the question above, I was just following up on a conversation I had with a guy in Springfield. He had an R something engine, and told of horrific vaporlock problems, but swore all went away with the installation of an aluminum intake.

DEEPNHOCK
08-23-2011, 09:41 PM
Well, I could have suggested clothespins:rolleyes:

I have added diesel during the hottest months in Florida, and it has always seemed to help.
I never cleared it with any engineers, as they never agree with anything I say anyways.:rolleyes:
(I can say the putting too much diesel in just makes your car stink like diesel fuel)
Jeff:cool:


Agree with all Jeff's comments above, except:Jeff and I will have to agree to disagree on this one. Petroleum engineers have convinced me nothing good comes of putting diesel in gasoline.

jack vines

JoeHall
08-23-2011, 10:02 PM
I think I willl give diesel a try. Nothin ventured-nothin gained. I have saw people with 15-20 clothes pins clamped strategically (from one end to the other of the gas line). Some said it helped, others weren't so sure.

Having a fuel return line allows one to drive away quicker, instead of waiting a couple minutes at high idle for solid gas to enter the line and fill the float bowl. But it will start hard. I had return lines on all Studes in teh California desert, and that was my experience. Problem is, when the in-line filter gets even a little dirty it will start returning so much fuel to the gas tank the engine will starve. Once in KY, as the filters got dirty, I just pluged the lines off. My cars from the desert still have the return line in place, but plugged off. They were not much trouble to install initially. I used copper line, and plumbed into a 1/8" pipe plug with 1/4" line fitting in the fuel filler spout, about six inches down from the cap.

Joe H

DEEPNHOCK
08-23-2011, 10:11 PM
Copper is a no-no for fuel lines.
Vibration can cause it to crack and leak...


<snip>
I used copper line, and plumbed into a 1/8" pipe plug with 1/4" line fitting in the fuel filler spout, about six inches down from the cap.
Joe H

JoeHall
08-23-2011, 10:20 PM
I know, but I spent a 30 year career living on the edge (Marine Corp) :)