Will a cold air intake stop hot fuel problems in desert climate ? ? ? ? ? ? ? ?

[skip68]

I have been doing allot of thinking of ways to help with cooling the carb.   My air cleaner is just sucking in the hot air from the engine and radiator in traffic.  It is like an oven under the hood hear in Vegas and we see temps over 100 degrees plus for months.   So, I was thinking if I put some sort of cold air intake that it would make a huge difference and stop the carb from getting as hot.        These Chargers seem to have bad ventilation under the hood and if you live in a desert area I think it's a must have.         I'm not taking my hood off or cutting my hood for a scoop.        

[maxwellwedge]

I think you would have better luck with some kind of phenolic carb spacer and a carb heat shield type of gasket deal.

Not sure what kind of carb you have. Have a look at these links. It should help if your fuel is boiling in your carb.

http://store.summitracing.com/egnsearch.asp?Ntt=phenolic+carb+spacer&searchinresults=false&Ntk=KeywordSearch&DDS=1&N=700+302859+115&x=29&y=9

http://store.summitracing.com/egnsearch.asp?N=700+115+302859&D=302859

[ACUDANUT]

Ya, you need a Carb spacer to help isolate it from a Hot Intake.

[67_Dodge_Charger]

Cold air intake will help with putting more air in your engine quicker.  Add a carb spacer for more hp; every little bit helps.  By getting fresh air from the outside of the engine compartment you will help with quicker throttle response plus you will notice differences in response with difference in air pressure and humidity and air tempersature. 

It will liven up a motor and help with hp plus you could  realize a potential in better gas mileage.  The power gain is mostly noticed in the throttle response.  Are you experiencing vapor lock or hard starts?

An intercooler will help but that is used mostly with turbo systems. Cold Air equals more horsepower.

[green69rt]

I wonder if you measured the temp under the hood in someplace like kansas and then measured it in Death valley, what the difference would be.  I bet it wouldn't be a lot.  I would tend to say:

1) insulate the carb from the intake ( a spacer).
2) insulate the gas line in the engine compartment.
3) make sure the carb and ignition are set right.
4) Maybe then think about a cold air intake.

[Ghoste]

Like everyone else is saying Chuck, a cold air intake isn't going to stop fuel problems, but it is going to help.

[skip68]

    Thanks guys.    I'm running a 440 30 over, Demon race 750 carb, Torker II intake, mopar 292 cam, Indy cast heads, Ross race pistons, gold roller rockers.....   I put a 1/2" wood with fiberglass spacer under the carb and it seems to be leaking.       I'll go find a 1" spacer tonight or in the morning.  I will have to find a different air cleaner because I don't have anymore room under the hood with the 1" spacer.   I put a cooking thermometer in the radiator and the hottest it got to was 195 degrees.  So I know the motor's not running hot.  When I go to touch the carb it's hotter than hell.  Time to go shopping again.   

[mopar_nut_440_6]

   Thanks guys.    I'm running a 440 30 over, Demon race 750 carb, Torker II intake, mopar 292 cam, Indy cast heads, Ross race pistons, gold roller rockers.....   I put a 1/2" wood with fiberglass spacer under the carb and it seems to be leaking.       I'll go find a 1" spacer tonight or in the morning.  I will have to find a different air cleaner because I don't have anymore room under the hood with the 1" spacer.   I put a cooking thermometer in the radiator and the hottest it got to was 195 degrees.  So I know the motor's not running hot.  When I go to touch the carb it's hotter than hell.  Time to go shopping again.   

If you are running into air cleaner clearance issues I would think a 1/2 inch phenolic spacer would be fine. I  personally cannot see the extra 1/2 making a huge difference but I am no expert on this matter.

[67_Dodge_Charger]

Death Valley does have potential for a higher air temperature even compared to eastern Montana where the temperature could reach 118*.  Kansas I am sure has a much higher humidity than Death Valley and of course Montana.  The cooling system is taxed at these extreme temperatures as many of us have experienced.  I would hope that the thermostat is keeping the engine at 180* give or take.  That is if everything is operating properly.....

The air temp in a engine compartment will differ with variances in outside air temperature; try living in areas with extreme high or low temperatures.  What temperature does your car like?  What humidity does your car like?  Is the car running lean?  

There most likely is a leak in the coolant system that is creating higher engine compartment temps....    Or your radiator, water pump is not able to keep your car cool.   There are some very good additives for the cooling system that  reduce engine temps and add life to your cooling system.  Is the car kept in a temperature controled garage during the hot days of Vegas?  Like what the others have said insulating the fuel line and a carb spacer will help with fuel temps.  

[67_Dodge_Charger]

"High performance cooling.
Purple Ice is a high performance synthetic radiator coolant additive for both gasoline and diesel engines. It is formulated to reduce the surface tension of the coolant, which improves heat transfer through the cooling system, while providing additional protection against rust, corrosion, and erosion. This additive prevents the formation of scale deposits in the radiator for optimum coolant flow and lubricates the seals of the water pump. One bottle will treat three to five gallons. It is ideal for use in straight water racing applications or in antifreeze/water mixtures. Purple Ice is compatible with traditional ethylene glycol antifreeze (green) and GM Dex-Cool antifreeze coolants."  From summitracing website.   

I am not sure if this brand was used in the Hot Rod tour last year or so by some of the participants, but it help with cars experiencing overheating.  Do you have access to equipment to check surface air temperature on the intake and other areas in the engine compartment? 

[skip68]

Thanks 67_Dodge_Charger for the tips.  I'll get a digital temperature gun in the morning.  The car runs fine on cool days like 60-70 degrees.  But once it's 80 degrees and up it runs bad.  I have a huge 32" Griffin Alum. radiator so it should keep it cool.   As long as I'm moving it's not to bad but as soon as I get into stop and go traffic it starts getting bad and you can smell the fuel real strong.   I am changing plugs tomorrow and setting the gap at 35 instead of 40.   I wonder if the 1/2" wood/fiberglass spacer is causing some of the problem ?  Will the phenolic spacer make that much difference from the wood one ?  I'll find out I guess.

[67_Dodge_Charger]

Definitely replace the carb spacer with a phenolic spacer.  Is there a fan shroud? Do you have AC?  Is the radiator clear  of debris, no bug or heavy dust?  Sounds like a gremlin that you will have to chase until you finally capture it.

[mopar_nut_440_6]

I live in a cooler climate up here in the north but we do have our days of warm weather. One thing I did notice sitting in the staging lanes in Ashcroft where it is as warm as the weather in Vegas was vapor lock issues. I changed my fuel line to 3/8" and fabricated a cool can out of a  can the size of a Charger vacuum canister with a plastic lid. I added a drain cock to the bottom so I could drain it after the ice had melted. I then wrapped some 3/8 copper tubing  around a piece of pipe to create a row of coils and added these to the can with the inlet protruding out of the bottom and the outlet at the top. I also bypassed my mechanical fuel pump on the engine and used the electric and kept the fuel line as far away from the headers as possible. This totally cured my fuel problems and I found I did not even need to fill up my cool can with ice or water. I believe you could hide the can behind the grill if you wanted. This was alright on my old drag/street car but maybe is not what you want to do on your GL. I just thought I would share!

[67_Dodge_Charger]

mopar nut where did you mount the fuel pump and route the fuel line?  An ice can is a great idea, did you coil the fuel line in the can?

[mopar_nut_440_6]

I mounted an electric pump in the rear off the frame rail in front of the tank where you see most people mounting them. The lower the better but be careful you have enough clearance. I put the coil inside the can and routed the intake and outlet through holes I had cut through the side which I sealed with silicone. That is the worst part but the whole process took under an hour and cost me about 5 bucks and worked flawlessly. In retrospect the 3/8 line and re routing away from the exhaust may have been all that was required but I did it all in one shot as I did not want to run into the issue when I came back to the strip.

[ACUDANUT]

 Don't forget a viscus fan clutch.  That adds 15 Hp and helps too.

[maxwellwedge]

His problem does not sound like water temp - that looks fine. Run a 175-180 T-stat anyway. Go with the phenolic and the heat shield. The heat shield was standard issue with the '70 LT-1 (gasp) Chevy and did the job. You need to get the heat away from the carb.

[ACUDANUT]

 Ya, I know. Thanks. Just thought I would add that. 

[green69rt]

Here's another thought.  Even though the temp indication is what it is the actual combustion temp can be different.  Wall thickness, fouling of the cooling channels and so on can affect how you engine performs.  I don't know how you fix these problems outside of a full engine hot tank and rebuild.  Maybe others can give some clues.  Beyond a rebuild you need to keep the engine temp (read this as combustion temp) down.  Some of the above comments should help.

[skip68]

My engine is new with about 1500 miles on it.   

[Ghoste]

You could always just move to a cooler climate.  Canada is great except for the rampant socialism and, oh yeah, that rust thing.

[firefighter3931]

Overheating can also be caused by improper tuning ; a lazy advance curve on the ignition or a carb that's running lean will cause overheating issues as well. 


Ron

[67_Dodge_Charger]

Overheating can also be caused by improper tuning ; a lazy advance curve on the ignition or a carb that's running lean will cause overheating issues as well. 


Ron

I agree with Ron since your engine has only 1500 miles on it.  Check your spark plugs. 

[mopar_nut_440_6]

Didn't you just put a new carb on your engine a couple of weeks ago? Was it heating up prior to the change?

[500INCHBIRD]

Cold air is only so cold at a 118 degrees.Sounds like timing.Or a mechanical problem.How big a bore is your motor now after having been rebuilt?.Loss off material in the cylinder wall can result in a higher operateing temp which is normal.

[skip68]

I guess I have exhaust leaks on both sides for some reason.  I wonder if that's creating a ton more under hood temperatures ?  I put in a triple gauge cluster (water temp, oil pressure, volts) and ran the car in stop and go traffic yesterday and the car is running right at 192 degrees.  The hottest I've ever seen this car get is 197 for a minute and then went back down so I know my carb and timing can't be too far off because it's not running hot.    I'm going to look at the exhaust leaks in the morning when the car is cool.   I will get new gaskets and replace them and hope that helps.   Do you guys think that the exhaust leaks are causing the problem ?  The car is running great until the fuel gets hot.  It will burn rubber in first gear all the way up to 50mph now so I know I'm making headway.   

[mopar_nut_440_6]

I guess I have exhaust leaks on both sides for some reason.  I wonder if that's creating a ton more under hood temperatures ?  I put in a triple gauge cluster (water temp, oil pressure, volts) and ran the car in stop and go traffic yesterday and the car is running right at 192 degrees.  The hottest I've ever seen this car get is 197 for a minute and then went back down so I know my carb and timing can't be too far off because it's not running hot.    I'm going to look at the exhaust leaks in the morning when the car is cool.   I will get new gaskets and replace them and hope that helps.   Do you guys think that the exhaust leaks are causing the problem ?  The car is running great until the fuel gets hot.  It will burn rubber in first gear all the way up to 50mph now so I know I'm making headway.   

Does the car pull fairly well  off the line and then start to bark and puke when it is hot? If so you may be expieriencing a vapor lock issue.

[skip68]

Yes !   It runs great for the first 10-15 minutes or as long as I stay moving.  But once in stop and go traffic for 5 minutes or so it starts running ruff and if I go wide open from a stop it goes up to 2500rpm or so and then does just what you said.     bark and puke like it's missing or running out of fuel and I can smell fuel.   

[mopar_nut_440_6]

Do you run an electric fuel pump? If so I would route your fuel line away from your headers and bypass the mechanical pump and see if this resolves the issue. If it does then you can decide what changes you want to make. It definitely sounds like  a vapor lock issue where the fuel is actually vaporizing in the fuel line before it gets to the carb. Like I said previously I had the same issue and solved it by going to a 3/8 line and routing my fuel line away from the exhaust, bypassing teh mechanical pump as well as making a cool can which may or may not have helped.

It will be cheap and easy to add a chunk of rubber line to test this out. If it work then you can decide how to proceed from there.

[skip68]

Thanks, I'll give that a shot.  I have a mechanical pump.  What would be the cheapest electric pump to try this ?

[500INCHBIRD]

Why use a cheap pump that will only lead to more problem's?Edelbrock has a couple really good electric pump's.Remember cheap componets usaully never aid in fixxing a problem.

[mopar_nut_440_6]

I have heard that the Mallory's are quieter than many of the pumps out there and still work well. You will want to mount the pump as close to the tank as possible because electric pumps are designed to push fuel not pull.  Also, as low as you can get it without having it so low it gets pounded off or hit with round debris or small animals! If you install the electric pump first you may want to leave the line running through the mechanical first just to test.

[Steve P.]

Damn Skip. I cannot believe you haven't discussed this with VegasMike... You should know that we went round and round with this a few years ago and it took lotttttttts of work to figure out and fix the problems...


1) It is GD HOTTT in Vegas.
2) He had a faulty fuel pressure gauge.
3) The wood and Phenolic spacers will work the same, but I trust the phenolic spacer much more.
4) Under hood temps there ARE much hotter there than most other places in country as the ambient temps are much higher. Nothing to cool under the hood. 
That doesn't mean other places don't have hot air under their hoods. Just that you are pulling 110 degrees through your radiator. most other parts of the country are well below that. Thus trading cooler air.

After trying loads of things on Mikes Charger, in the end it was running an electric fuel pump with a bypass regulator and a (RETURN) line back to the tank. He was burning up Holley black pumps left and right until the return line.

One other thing: I don't care WHO'S gauges you bought, test the gauges properly before trusting them...

Lastly, You have to have lots of time and talent to properly tune a Demon carb.  Any carb for that matter, but more so in Demons. I would suggest you save some bucks and step into the HOLLEY or PROFORM WORLD... All carbs have their place and it seems more and more that the Holley's and Proforms just keep taking the cake....

Hope this helps buddy... The very hot days in Vegas are made for swimming. Not so much hot motors..... 

[skip68]

    Thanks Steve.   I have talked to Mike and lots of others.   BUT NOW I KNOW !!!!!!    I called Mike last night and asked what pump should I get from Summit and what about a bypass regulator and he said STOP !!!   "Don't buy anything until you look at mine.     I know for a fact now that I must run Electric fuel pump with bypass regulator and return line.      I did change my t-stat today to a 160* and now my car runs at 168* to 172* while driving.         I will be getting the proform carb when I can afford it.   I'll tell you what, that proform on Mikes is snappy as hell.               I do wonder if my gauge is off by 10 degrees.   When I had the 180* T-stat in it would run at 190*.    Now with the 160* T-stat it runs at 170*.          So, it seems my gauge reads 10 degrees more than what the T-stat is rated at.   

[Steve P.]

STOP!!!  lol....   You don't HAVE to run an electric pump. You can run your stock pump with a bypass regulator and a return line. I prefer the electric mostly for security reasons. Mike can show you what I mean. The big thing about Mike's set up is where the car is driven. 2300 ft. above sea level and the heat you deal with there makes for some tough wear and tear. So in Vegas with a car that makes plenty of it's own heat,  I don't think there is much that could be considered overkill. We went round and round with Mikes Charger for a while trying to get his fuel system to work without trouble. The return line helps in keeping his fuel pump cool. He went through a bunch of pumps before I talked him into the return line....

As far as your gauge being off 10 degrees, well it could be. It could also be off 50 degrees... The ONLY way to know if a t-stat AND gauges are close to their intended settings is to properly test them. Do some homework on gauge testing and follow it step by step. The big thing people screw up on when testing is setting the gauge bulb or stat directly on the bottom of the pan. They should be hung in the water, but above the pan not touching it... Otherwise you will get a false reading there too...

You will NOT be let down at all by the Proform... more and more guys here every day will vouch for them.

[mopar_nut_440_6]

STOP!!!  lol....   You don't HAVE to run an electric pump. You can run your stock pump with a bypass regulator and a return line. I prefer the electric mostly for security reasons. Mike can show you what I mean. The big thing about Mike's set up is where the car is driven. 2300 ft. above sea level and the heat you deal with there makes for some tough wear and tear. So in Vegas with a car that makes plenty of it's own heat,  I don't think there is much that could be considered overkill. We went round and round with Mikes Charger for a while trying to get his fuel system to work without trouble. The return line helps in keeping his fuel pump cool. He went through a bunch of pumps before I talked him into the return line....

As far as your gauge being off 10 degrees, well it could be. It could also be off 50 degrees... The ONLY way to know if a t-stat AND gauges are close to their intended settings is to properly test them. Do some homework on gauge testing and follow it step by step. The big thing people screw up on when testing is setting the gauge bulb or stat directly on the bottom of the pan. They should be hung in the water, but above the pan not touching it... Otherwise you will get a false reading there too...

You will NOT be let down at all by the Proform... more and more guys here every day will vouch for them.

A return line is also a good idea for prolonging the life of a good pump. I know a Holley Blue pump, in my experience, does not have a very long life without one. Is Vegas Mike still running his mechanical pump? Has anybody built an enclosure to reduce the sound from an electric pump? I have a Holley Blue pump and they are very noisy! I am trying to build a sleeper. Does anybody have any pictures of one of these pumps installed in a way which makes them a little less easy to see? The only spot that I see them mounted is off of the RH frame rail.

Sorry to post this on this post but I think it is related information.

Cheers,

[skip68]

Mike is running an electric pump.   I was thinking the same thing about some sort of box to reduce pump noise.      

[mopar_nut_440_6]

Mike is running an electric pump.   I was thinking the same thing about some sort of box to reduce pump noise.      

Once you get everything together would you mind posting what parts and numbers you used in the setup as I will be going a similar route. Pics too!

[Steve P.]

You are correct about prolonging any pumps life with a return line. So called, "by-pass" pumps do by-pass, but they are still spinning away creating more heat and a higher amp draw. Neither of which do you want.

NOTE: While Vegasmike was having these pump problems with by-pass type electric pumps I called a few top brand manufacturers. BOTH of them told me that a by-pass regulator and return line was the only way to go. EVEN with their own by-pass pumps!!!  

You do want to match a pump to your combination.  All the pump companies will help you do that.

As far as pump noise, I think the best fix I have heard was cutting a piece of a heavy truck rubber mud flap and installing the pump hanging from it. NOT just sandwiching the rubber, but bolting the rubber to the frame and then a few inches lower bolting the pump to the rubber. You will need to run a separate ground this way.   I don't like the idea of creating a box for noise suppression. While that may work for noise, it will also create an oven effect. In essence you would insulate and keep both noise and heat created by the pump inside the box and induce the problem we are trying to fix. HEAT..   

Hope this helps...

[mopar_nut_440_6]

You are correct about prolonging any pumps life with a return line. So called, "by-pass" pumps do by-pass, but they are still spinning away creating more heat and a higher amp draw. Neither of which do you want.

NOTE: While Vegasmike was having these pump problems with by-pass type electric pumps I called a few top brand manufacturers. BOTH of them told me that a by-pass regulator and return line was the only way to go. EVEN with their own by-pass pumps!!!  

You do want to match a pump to your combination.  All the pump companies will help you do that.

As far as pump noise, I think the best fix I have heard was cutting a piece of a heavy truck rubber mud flap and installing the pump hanging from it. NOT just sandwiching the rubber, but bolting the rubber to the frame and then a few inches lower bolting the pump to the rubber. You will need to run a separate ground this way.   I don't like the idea of creating a box for noise suppression. While that may work for noise, it will also create an oven effect. In essence you would insulate and keep both noise and heat created by the pump inside the box and induce the problem we are trying to fix. HEAT..   

Hope this helps...

Will the factory return line work for this or will the diameter be too small. I normally work on modified vehicles where looks do not matter but this time I want my car stock appearing.

[Steve P.]

In my opinion the stock return lines are better than NO return lines. It's all about easing the work of the pump and keeping the fuel from sitting near a heat source for any length of time.

In every kind of pumping situation I can think of, the return line is larger then the pressure line. A/C, power steering, fuel transfer systems, (I have worked alllllot with them), hydraulics, steam, you name it. The high pressure side is figured by the need, (pressure and volume). The return and or bleed of systems are always larger.

Berry Grant's site shows typical fuel systems that they recommend. Typical racing systems are from the tank to the pump= 1/2" line. Pump to the regulator = 3/8 line. Return from the regulator back to the tank is 1/2" line. Regulator to bowls= 3/8 line. I think this is up to 7 or 800 HP. This is overkill for a daily driver with 3-400HP, but it damn sure WON'T hurt.... 

[skip68]

Thanks Steve.  I'll go bug Mike tonight and check out his set up.   

[Steve P.]

No tools around Mike's Charger, Chuck.... 

[skip68]

Yes sir. 

[mopar_nut_440_6]

No tools around Mike's Charger, Chuck.... 

Is there a link to his Charger?

[skip68]

I'll ask him tonight to post a few pics of the areas you need to see.   

[hemirr]

Skip68 -  I also have a 68 charger coming out of a 7 year rotisserie resto.  440 motor mild cam with 1/2 wood spacer and Holley carb.  I have an over sized Alu radiator with a 7 bladed fan with shroud.  Here in S. Florida this year its been 95-98 degrees every day with about 85-90% humidity.  While at speed temps run around 170.  10 minutes in traffic it starts to run real hot, motor pings like crazy.  I am currently experimenting with different octane gas mixtures to calm down the knock (along with timing changes)  One thing is what carb are you running?  I originally had an Edelbrock and it ran like crap in the heat.  Their float bowls are on the side, right over the heat crossover.  Switched to a Holley and that side of things are fixed.  The drivability is like night and day, just knocks when hot.  I run a stock mechanical pump with no issues.

[Steve P.]

Skip68 -  I also have a 68 charger coming out of a 7 year rotisserie resto.  440 motor mild cam with 1/2 wood spacer and Holley carb.  I have an over sized Alu radiator with a 7 bladed fan with shroud.  Here in S. Florida this year its been 95-98 degrees every day with about 85-90% humidity.  While at speed temps run around 170.  10 minutes in traffic it starts to run real hot, motor pings like crazy.  I am currently experimenting with different octane gas mixtures to calm down the knock (along with timing changes)  One thing is what carb are you running?  I originally had an Edelbrock and it ran like crap in the heat.  Their float bowls are on the side, right over the heat crossover.  Switched to a Holley and that side of things are fixed.  The drivability is like night and day, just knocks when hot.  I run a stock mechanical pump with no issues.

New Port Richey, Fl. here.  Are you using a shroud?  Also what t-stat is in it?

Something I was reading a few weeks ago was a guy in the same boat as many of us. Trying everything he could think of. I answered him with a few things and got him to send me a few pics. Once seeing his set up, (aftermarket monster aluminum rad), I told him I thought the rad sat too low. His upper hose was higher than the top of the rad. tank. He said he has tried everything else under the sun and would try raising it. I got an email from him saying he raised it just over 3 inches and it runs under 200* in traffic and sitting at lights.  All fixed...

I have seen this on a few cars before. Your rad. will seek it's own fluid level. If it is mounted too low if will have a large amount of air in the top of the rad. once the engine comes to temp.  Simple rule is to keep the rad at least as high as the OEM rad. was. The cap/fill should be higher than your t-stat.

[mauve66]

when i was re-searching mine i noticed that the 440-hemi motors had a 3/8 feed line and a 5/16 return line plumbed as a set for the car so i just got the b-body setup for a hemi and just clipped them into the same place as the old lines.  I had to drill out the pass through at the torsion bar support (i think that was were it was at) to get both lines through it.  i used some JB Weld to insert a metal tube into the tank for the return line to connect to.

[hemirr]

I am running a shroud.   The radiator is a Griffin muscle car series that is 1 1/2 times thicker than the stock unit but yet runs hotter ?  It is mounted perfectly centered so the cooling fins fill the support opening with no overlap.  As  a matter of fact it it can not go any higher as the cap will hit the hood and the rad cap is higher than t-stat. The top hose is a little higher that the tank as it is setup for AC and needs the belt clearance.  I can cut it down to lower it a bit but when the AC go's on this fall it will may have to be raised for clearance.  I have tried a a 160, a 180 and 195 degree t-stat with same results.  So for the best combo believe it or not is not t-stat.  I know all about the reason this isn't supposed to work but by far it is the best results to date.  The one thing I did notice is that it looks as the water pump pulley is a a little smaller diameter than a friend of mine with same car and no cooling issues. If so the water pump maybe underdriven a bit witch would make a difference at slower speeds.  Maybe, its a thought.