easier start mods

[citron fella]

howdy i recently purchased a numbers matching 1971 340 challenger i have noticed when she's hot has a difficult time starting what can i do to make my hot Challenger start easier i don't want to hurt my starter thanks drive safe

[rUNCHARGER]

That's hard on the camshaft too. Most likely it is boiling the fuel out of the carb float bowls. An electric fuel pump to prime the carb before hitting the key is usually the answer.

Sheldon

[4Cruizn]

Or a spacer between the carb and intake manifold . . . helps keep the carb cooler . . .

[jimynick]

And/or a heat shield for that poor, old, roasting starter. There're small tool box size inductive amp gauges that you hold against the positive battery cable and have someone try to start it and read how much amperage it's trying to suck down that wire. That'll tell you were you need to go from there as to whether it's fuel or electrical. 

[GoodysGotaCuda]

Cool fuel, good spark [I used an MSD box] and a mini-starter worked very well for me.

[1 Wild R/T]

Since the fuel keeps getting worse & worse starting an old car has gotten much more difficult..... I've blocked heat to the intake, multi-spark ignition, carb insulator.... It got better but never great..... Recently added FiTech EFI... Hot or cold makes no difference standing outside the car reach in & hit the key & the car fires immediately..... Nice!

[YO7_A66]

 Over the last few years with a carb, these are the items that I have changed to help with the crapty gas.

-Mini Starter
-MSD Ignition
-Return line to tank
-Electric fuel pump (I have a priming button that I use to fill the bowls before each startup)
-heat insulator gaskets/plate under carb
-Cooler spark plugs (NGK -7)
-Royal Purple Ice in radiator
-180 thermostat (was 195)
-Aluminum intake (cross over blocked). I have an Edy RPM, but the Airgap should be a better setup to let the heat out.
-Open air cleaner lid
-Opened up the vents in my hood to allow the heat to get out
-Holley Choke Delay #45-267

The E10 gas is terrible in these carbs. It has a lower boiling point than gas and it collects water. Anything that you can do to keep the heat down inside of the engine compartment will help a little bit. The first 30-45 minutes or so after shutdown is when the heat rises (heat soak), then it starts to cool down. This is when the fuel is boiling out. Keep the fuel as cool as you can during this time frame and then get cool fuel back in the carb for startup will help.

If you have an A/F meter, it will show you a 16+ lean spike on a hot restart. The fuel is gone or weak and you have to have a stable cool fuel supply to bring the A/F back down to where there is a stable fuel pressure again. This is where EFI shines. It is under pressure all the time and it does not change like the pressure in a carb setup.

[mopar jack]

since my car is usually only driven to shows or cruise nights I open the hood as soon as I park to let the heat out.

[mopar jack]

The subject of vapor pressure and boiling points of gasoline comes up quite often so I posted an in depth explanation of gasolines physical properties. It's a long read and very technical but the first 3-5 pages and graphs will explain what most of us experience with our carburated cars. http://www.chevronwithtechron.ca/products/documents/69083_MotorGas_Tech_Review.pdf

[1 Wild R/T]

The subject of vapor pressure and boiling points of gasoline comes up quite often so I posted an in depth explanation of gasolines physical properties. It's a long read and very technical but the first 3-5 pages and graphs will explain what most of us experience with our carburated cars. http://www.chevronwithtechron.ca/products/documents/69083_MotorGas_Tech_Review.pdf

Info like that it almost seems like you work at a refinery or something... 

[mopar jack]

Yea 33 years and I worked on a lot of the test equipment that measured gasoline, diesel, jet fuel and lube oil properties. Also maintained equipment that monitored air emissions for the EPA. Been retired 9 years and don't miss it at all.

[chargerdon]

We almost all have the problem with fuel boiling out of carb and long cranking for restart after hot engine sits for more than 5-10 mins...  and less than an hour.    The electric fuel pump only cures the empty bowls, it doesn't help the problem that the boiling fuel went down into the engine and it will be flooded.  Especially those of us with aluminum intake manifolds, as they transfer the heat into the carb at a faster rate than the older cast iron. 

The only true "cures" other than to switch to fuel injection are to:

1) put in a phenolic heat spacer to try to keep some of the heat from transferring to carb.
2) Open the hood as soon as you park it, to let the heat out and hopefully prevent the boiling of the gas.
3) Recognize that the engine is probably flooded (between the 10 min and 1 hour since shutoff), and floor the gas pedal as per flooded engine starting technique.  Then let it crank till it clears and starts.

I had an electric fuel pump on my 66 Charger with a toggle switch for operation.   I used to turn it off about 30-45 secs before shutting off the engine and this would help to empty the bowls to prevent boiling and flooding.   Then i would turn it on before trying to start the engine and wait a few seconds to hear the sound change as pressurization occurred, pump once or twice and then start the car.   It would start in about 1-2 secs like this, probably the amount of time it takes to suck the mixture thru the intake passages.   Only trouble is that i hated the Noise of the electric fuel pump.   It was a high pressure (14 psi) Holley with an external regulator to cut back to 6-7 psi.   Hated it !!!   It is now off !!

[citron fella]

thanks for all the input. i only take her out once a week and she's just a cruise and show car but i'd like some reliability there if i have to start her again after shutting her off. i can't remember my dad's 318 car starting like this even my 27 y.o isuzu with a Weber fires up quick. my neighbors replaced his starter in his 68 442 to help with his starting issues. a "mini starter" might be something i'm interested in i really don't want to change the way the engine bay looks with the better after market parts. she's pretty and 46 y.o and has nothing to prove but a quick start is important. where can i purchase a mini starter and what do y'all recommend. thanks in advance drive safe

[1 Wild R/T]

i can't remember my dad's 318 car starting like this even my 27 y.o isuzu with a Weber fires up quick.

Your dad's 318 car didn't try to burn the stuff they sell as gasoline these days....  Seriously the fuel now is formulated more based on emissions & modern fuel injected cars.. A fuel injected car keeps the fuel pressurized so it can't boil off or evaporate..   

And as far as your Izuzu a 4 cylinder has the carb hung off the side away from the rising heat coming off the engine, a V8 has the carb centered right over all that rising heat..  Little different....  The insulator plate/spacers do help, the electric fuel pump would help.... End of the day I drive allot & chose to quit fighting a losing battle ... Under hood my car looks pretty well stock, you need to look close to see any signs of EFI... And it starts hot or cold, red cold I can fire it up & drop it in gear, I could never do that with the 5-6 different carbs I tried throughout the years.... And currently it has a bigger cam than it's had for the past 20 years which means it should be worse to drive cold....  It also runs better all around, no flat spots, no stumbles, no hesitation... Much less exhaust stink....  Not saying it's for everybody but it sure has been a huge improvement for me....  20-30 years ago I liked tweaking a carb to get it to run perfectly, these days I done want to work on a hot engine spilling fuel & worrying about the whole thing catching fire... Last few years I would make 1-2 changes to a cold engine & go drive it to see if I'd fixed whatever gremlin I  was chasing then let the car cool off before doing any more.. With life getting in the way that meant problems take weeks to sort out....  I bolted this thing on spent time chasing the details to get it just how I wanted it the first time & when I twisted the key the first time (well Ok the third time) it fired up & idled beautifully... Took it for the first drive after throughly looking it over for leaks & what not, it ran great, I've done a few tweaks just cause thats what we guys do but now I can change the mixture idle speed or twenty other setting with the hand controller from the drivers seat.....   Couldn't be happier...

[citron fella]

what's your EFI set up and cost?