The carb base DOES serve a purpose!
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I totally agree that the carb spacer is there for the winter/colder months. Remember that gasoline has a high latent heat of vaporization. As the gas changes state from liquid to vapour it absorbs heat. The carb spacer might be there to provide heat too. My Dad who worked at both Ford and GM thru his whole career as an engineer told me stories about the Carb Engineers making test carbs that would ice over due the gas changing state.
I think the *other* reason that the water heated/cooled spacer is there is from a steady state point of view. Regardless if the spacer is supplying heat or preventing heat from the intake it would make the carb run at a more consistant temp. And with the consistant temp, it would take one variable out of the operating parameters for the carb. It *should* make the carb easier to tune.
I too have wondered if the spacer prevented heat from the intake from conducting up to the carb. The only way to answer that is to test, get the thermocouples out!!!
I think the *other* reason that the water heated/cooled spacer is there is from a steady state point of view. Regardless if the spacer is supplying heat or preventing heat from the intake it would make the carb run at a more consistant temp. And with the consistant temp, it would take one variable out of the operating parameters for the carb. It *should* make the carb easier to tune.
I too have wondered if the spacer prevented heat from the intake from conducting up to the carb. The only way to answer that is to test, get the thermocouples out!!!
60s Refugee
Well-known member
One of the biggest problems we had with the 200's was that on hot 90+ days they vaporlocked. That fuel line is long, exposed, and right next to the engine for most of it's length. I expect that the carb base will help cool the fuel but that was not it's design function. It was to keep the choke under control. I had vapor lock last summer just as you described and the carb base is fully hooked up.
So here is what I did.....I got a long piece of asbesto's tubing like what goes on the heat riser tube, cut off the flared end of the line, slid it over the fuel line, slid the nut back on and reflared the end. It hasn't vapor locked since. Back in the day we'd wrap the line with aluminum foil, or friction tape, or rubber hose, anything to keep the heat away from it.
Todays cars don't have vapor lock problems like back then because of the higher pressure in the lines, the electric pumps, and the way they route the lines. Vapor lock is one of the things that real men hafta' put up with!
Harry
So here is what I did.....I got a long piece of asbesto's tubing like what goes on the heat riser tube, cut off the flared end of the line, slid it over the fuel line, slid the nut back on and reflared the end. It hasn't vapor locked since. Back in the day we'd wrap the line with aluminum foil, or friction tape, or rubber hose, anything to keep the heat away from it.
Todays cars don't have vapor lock problems like back then because of the higher pressure in the lines, the electric pumps, and the way they route the lines. Vapor lock is one of the things that real men hafta' put up with!
Harry
mugsy":3a7x1deu said:
I think this theory actually may be closer to the solution. Carb's love steady state operation. Come to think of it, IT does seem I have to adjust my carb a lot more now what I have no coolant hooked up then when I did have it hooked up (both 1V and 4V engine mods).
I like this theory.
I never had the vaporlock issue, even on really hot days with the coolant hooked up or not.
My background is Marine Engineering. I also took all the thermal courses like Mechanicals but mostly applied it to Marine enviroments (Designing ships, propulsion systems, HVAC, Auxilliary services, etc) and then working on them while I was a Naval Engineer in the CG, so I've seen engines from 1HP-30,000HP torn apart, and cooling systems the size of our cars...hehe.
I'll even go coach instead of business class 
Patrick66
Famous Member
Road trip! no, not really.
im pretty sure i can borrow something from a friend. if i just measure the temp of the spacer without the coolan lines hooked up, then with it hooked up that should be sufficient, right? ive been meaning to get an infared temp gun to measure the temps in my snakes cage so i might go ahead and buy one anyway.
im pretty sure i can borrow something from a friend. if i just measure the temp of the spacer without the coolan lines hooked up, then with it hooked up that should be sufficient, right? ive been meaning to get an infared temp gun to measure the temps in my snakes cage so i might go ahead and buy one anyway.
You must also consider the other contributing factors.
Less ignition timing = more exhaust heat = more carb heat.
Some of those extra vac lines installed on seventies cars would increase vac to the dizzy advancing timing in hot soak situations.
When a liquid travels from a high pressure area to a low pressure area, it is more prone to flash into a vapor = fuel pressure can have some effect. But the fuel can also have a cooling effect when it is squirted past the neadle and seat, provided you can move enough at idle in traffic.
When fuel is preheated in a long underhood line, it can aggrevate the problem. Do you have the factory steel line or a rubber line?
This is where a seventies pump with a return line can help. Any time I have a need for a regulator, I prefer a bypass regulator with a return line.
This is also aggrevated by the hot asfault that is preheating the line under the car.
Sometimes when we compare problems we overlook small things that can contribute.
Less ignition timing = more exhaust heat = more carb heat.
Some of those extra vac lines installed on seventies cars would increase vac to the dizzy advancing timing in hot soak situations.
When a liquid travels from a high pressure area to a low pressure area, it is more prone to flash into a vapor = fuel pressure can have some effect. But the fuel can also have a cooling effect when it is squirted past the neadle and seat, provided you can move enough at idle in traffic.
When fuel is preheated in a long underhood line, it can aggrevate the problem. Do you have the factory steel line or a rubber line?
This is where a seventies pump with a return line can help. Any time I have a need for a regulator, I prefer a bypass regulator with a return line.
This is also aggrevated by the hot asfault that is preheating the line under the car.
Sometimes when we compare problems we overlook small things that can contribute.
60s Refugee
Well-known member
Different carb, different age, different smog stuff, different mentality, stuff like that. There is no doubt that heat is the enemy of performance, as has already been established in this thread. It is also true that carbs love a stable environment, which has also been established. Detroit will tune things down to benefit everyone everywhere and in cold places like Montana, Minn, Maine, Wisconsin,Alaska, etc, it makes sense to warm the carb for guys like them. I have heard stories about carbs iceing up in below zero temps. Standard Oil brand gas used to advertise additives to prevent fuel line freeze up. Heck, my uncle during a visit from Florida had his radiator freeze up WHILE he was driving it! It was minus 15* that night with about a foot of old snow on the ground and no antifreeze in his coolant. There is another truth too, Detroit wouldn't foot the bill for researching a part and putting it into production that didn't have any practicle function. Average all this out and you can understand why the carb spacer is there.
I hooked the hose back up to mine on the new tri power just 'cuz it was there. The carb base provides a pivot bolt for the linkage, a vac for the PCV, and I drive in the winter. It also has that little passage for the stock choke function, but I'm not using that.
I drive to Fort Worth Texas every summer for a Nam Vet reunion. While there I had vapor lock with the stock system several times during 98* city driving as well as places closer to home all last summer, so I'm not sure how much the cooled plate helps, but, perhaps if it wasn't there at all the problem might have been even worse. I agree with those who suggest that 196* really ain't that cool!
Harry
I hooked the hose back up to mine on the new tri power just 'cuz it was there. The carb base provides a pivot bolt for the linkage, a vac for the PCV, and I drive in the winter. It also has that little passage for the stock choke function, but I'm not using that.
I drive to Fort Worth Texas every summer for a Nam Vet reunion. While there I had vapor lock with the stock system several times during 98* city driving as well as places closer to home all last summer, so I'm not sure how much the cooled plate helps, but, perhaps if it wasn't there at all the problem might have been even worse. I agree with those who suggest that 196* really ain't that cool!
Harry
Still using the base plate. No problems at all. Everything is rock steady.
But I gotta admit...I stuck a piece of fuel line in the heater hose as a flow restrictor. It seemed to me that the coolant was moving so fast that it was 1) not providing sufficient time to absorb heat and 2) providing excessive bypass in the cooling system.
But given that, it's working great!
But I gotta admit...I stuck a piece of fuel line in the heater hose as a flow restrictor. It seemed to me that the coolant was moving so fast that it was 1) not providing sufficient time to absorb heat and 2) providing excessive bypass in the cooling system.
But given that, it's working great!
Patrick66":3s69uwfi said:
hey if you want I can hop over and let you borrow mine. My girlfriend bought me a really nice snap on one for christmas and the only time I used it was to measure the temperature of my brakes one day... lol
