Timing 1970 440 HP

[poulinpro]

HI you guys helped me once lets see if you can again have a 1966 Plymouth 440HP motor Its Built I believe I now its got a hot cam in it thats all I no I assume It has some oter performance parts when it was built.The problem is this it overheats in traffic or idle I replaced the radiator with a Griffen 2 row 1/12 inch tubes 3" thick griffen told me it was good for 600 hp still overheats changed thermostat to 160* AND ADDED AFTERMARKET SHROUD still overheats was talking to one guy at car show today says I should put high volume water pump o as fins on impeller ware out. Anoter guy said don't waste your money it"s proabably a timing issue he said before I do anything ask a mopar guy hes a chevy guy but seems to know a lot I now have timing set a 5*BTC he says Witha built 440 to at least 15*BTC anybody know????? Ilooked at a few books some said %*before some said after TDC Im confuse he thinks it will solve problem he said chevy big blocks will do same if timing not right I just Don*want it running when I shut it off orpinging when I sted on it I run 93 octane gas with lucas octane booster so the Question is what should timing be for this built 440 Tanks Mike

 

[The Satellite Cometh]

Man, I am running a 3 row radioator in my car and it runs real cool. I drove that girl 650 miles in one shot and the thing didn't even get close to running hot. (Yes, i am sure the guage works).

The rule is the more rows the better.

 

[70Fish]

True for 3 rows, but not for 4. FYI there was a "cooling" article in one one the mopar rags that said adding a 4th row basically did nothing as the rear tubes (engine side), weren't getting enough air or something to that effect.

The rule is the more rows the better.

 

[Cranky]

Lean fuel mixture can cause overheating too....but 5* is a bit slow imo. I usually start around 10 at idle and go from there. How is your off idle throttle response? Does it light up the tires or seem kinda sluggish? Is the engine newly rebuilt? Are you having any issues with rust showing up in the radiator?

 

[67 B-body]

5 does seem a bit on the low side. I wonder how far open you have to set the throttle blades for idle at that low initial advance? maybe try 15deg initial and 28deg tottal. Also you'll probably have to lower the curb idle screw once the timing is advanced a bit. This can and does help with off idle throttle responce, because you develop more manifold vacuum with the throttle blades shut down. I believe this might help a bit on temp as well, because you let the combination of compression and ignition spark promote the burn. How much remains to be seen however.

 

[poulinpro]

Hi Guys thanks for the tips Ive been experimenting old school way I turned timing u took it out ran it engine was rattling bad to far advanced I believe took a few trips with tools keeped turning timing back till rattle was gone adjusted idle each time I adjusted timing think its right now probably 15* or so but stiLL over heats I think this Griffen alum radiator which is brand new and has 1/14 tubes dosent have enough ROWS only 2 probably not enough probably shoul of got 3 but Benji at Griffen said this radiator was good for 600hp (He"s probably going to sell me a bridge in Brooklyn next) OH well ps I use sonoco 93 gas with lucas octain booster so I think the rattles where timing issue its fine now but still overheats I ordered a 15"pusher fan from summit Ill see how that works thanks for everones input Mike

 

[poulinpro]

What do you think about this a guy at car show said it may be water pump he said impellers wear out from coolent and wear and dont flow the water like they should he suggested putting on a high velocity water pump????? I wrote to griffen radiator about the 2 row 700.00 radiator they said would handle this engine and dont lets see what they say??? thanks Mike

 

[67 B-body]

What do you think about this a guy at car show said it may be water pump he said impellers wear out from coolent and wear and dont flow the water like they should he suggested putting on a high velocity water pump????? I wrote to griffen radiator about the 2 row 700.00 radiator they said would handle this engine and dont lets see what they say??? thanks Mike

Just so everyone understands... Not enough water flow can cause overheating, BUT,,, to much can just as easily cause overheating!!!!
If the coolant doesn't have enough time spent in the radiator, it will never be able to tranfer the heat it carries through the cooling fins. This is seen when you remove the thermostat from your engine. In the Late model race car engines I used to build, we would change restrictor sizes " in place of thermostat" to adjust operating temps. you will find that going smaller in diam opening will in fact have the potential to increase the cooling ability of your system.
I'm not saying this IS your problem, but something to keep in mind when running things through your mind during diagnosis.

Cheers

 

[62MAX]

First of all,you don't need a $700 radiator,nor should you need a so called high performance water pump or pusher fan.All these cars whether it was a slant six or a Street hemi had no cooling issues with the origional components they left the assembly line with.Everyone seems to try to re-engineer things the car manufacturers spent millions on to make work.Half these cars didn't even have fan shrouds or 3 core radiators.First thing I would do in your case is make sure timing,idle speed and fuel mixture is correct. Also,you need a clean block,a lot of crud can accumulate over time.and a 180* thermostat should be no problem.You also didn't mention what coolant you are using.

I have two cars,one a 6pk Superbird,original 3 core radiator,fan and shroud with a 180* thermostat,will idle in 90* weather as long as you want and never go above 195* and the birds are noted for not being the best at cooling.The other car is a 62 Savoy wagon with a built .030 over 440,fairly radical cam,two fours and complete 3" Max Wedge exhaust plus I added air conditioning.Same thing,fixed 7 blade fan,factory 3 core radiator with factory shroud and water pump,also won't go over 195* in traffic.

Sit back and take a good look at what you have before you start throwing your money away.

I'm tired typing now,so good luck.

 

[daredevil]

Just so everyone understands... Not enough water flow can cause overheating, BUT,,, to much can just as easily cause overheating!!!!
If the coolant doesn't have enough time spent in the radiator, it will never be able to tranfer the heat it carries through the cooling fins. This is seen when you remove the thermostat from your engine. In the Late model race car engines I used to build, we would change restrictor sizes " in place of thermostat" to adjust operating temps. you will find that going smaller in diam opening will in fact have the potential to increase the cooling ability of your system.
I'm not saying this IS your problem, but something to keep in mind when running things through your mind during diagnosis.

Cheers

If you have too much flow it will push water out of the cap. Water is gonna dissapate heat no matter how fast it flows. Restricting it will only raise temps.Not gonna run any cooler with restrictors than it does unrestricted. with a stock pump.

 

[daredevil]

I would worry more about total timing as long as it starts well. My bb likes 40 to 41 degrees total with a hot solid roller cam. This has me at twenty three initial

 

[67 B-body]

If you have too much flow it will push water out of the cap. Water is gonna dissapate heat no matter how fast it flows. Restricting it will only raise temps.Not gonna run any cooler with restrictors than it does unrestricted. with a stock pump.

NEGATIVE......
This is absolutely incorrect..
Sorry to sound harsh, but it is fact..... Go pull the thermostat out of something, say a 96 Jeep Cherokee and drive down the higway for an hour or so. Tell me you dont see the temp guage go up.
How do I know????? I did it.
Also, like I said before. You can "and I have many times" gone to a smaller restrictor and decreased the engines operating temperature. It's just the way it works.... You have to let the water remain in the heat transfer device "the radiator" long enough to actualy pull the heat out of the coolant. Water "coolant" absorbs the heat from the engine, and the radiator transfers the heat energy into the air. No dissapation, and the coolant should not flow out of the cap by removing a thermostat except if it gets hot enough that the pressure /expansion increases and lifts the seal of the cap up off of the neck of the radiator.
This does happen in normal operation of the vehicle through heating and cooling cycles, especialy in todays automobiles running @ 215deg F. We expell a certain amount of fluid when pressure builds beyond the rating of the cap, and we also pull coolant from the overflow back into the radiator as the temps go down and expansion is reduced. I know this for certain because it's something that I would have to adjust, and this is the method. I also learned the particulars while in College earning my degree in automotive technology. That was before the engineering degree.
Sorry, just one of those when you know something for sure, you can't let it pass by. No harm meant! Just trying to educate or be informative.

 

[daredevil]

NEGATIVE......
This is absolutely incorrect..
Sorry to sound harsh, but it is fact..... Go pull the thermostat out of something, say a 96 Jeep Cherokee and drive down the higway for an hour or so. Tell me you dont see the temp guage go up.
How do I know????? I did it.
Also, like I said before. You can "and I have many times" gone to a smaller restrictor and decreased the engines operating temperature. It's just the way it works.... You have to let the water remain in the heat transfer device "the radiator" long enough to actualy pull the heat out of the coolant. Water "coolant" absorbs the heat from the engine, and the radiator transfers the heat energy into the air. No dissapation, and the coolant should not flow out of the cap by removing a thermostat except if it gets hot enough that the pressure /expansion increases and lifts the seal of the cap up off of the neck of the radiator.
This does happen in normal operation of the vehicle through heating and cooling cycles, especialy in todays automobiles running @ 215deg F. We expell a certain amount of fluid when pressure builds beyond the rating of the cap, and we also pull coolant from the overflow back into the radiator as the temps go down and expansion is reduced. I know this for certain because it's something that I would have to adjust, and this is the method. I also learned the particulars while in College earning my degree in automotive technology. That was before the engineering degree.
Sorry, just one of those when you know something for sure, you can't let it pass by. No harm meant! Just trying to educate or be informative.

I have to disagree. Doesnt work that way on my car. Maybe my aluminum radiator transfers heat better. Theres two schools of thought on this.I just agree with the newer theories.

 

[67 B-body]

Well,,, all I can say is..... You can lead a Horse to water but you can't make him drink.
LOL

 

[beezee]

Also make sure you have a good seal between the radiator and rad cradle,hood seal to rad cradle as recirculated air from the engine compartment will cause idle and low speed overheating.

 

[67 B-body]

I can also agree that you dont want it to take to long to get its way back into the engine wear it's needed to pull heat away! I think it's a happy balance of enough flow to keep the vaporing of coolant coming in contact with hot points in the engine, and yet keeping it in the air / slip stream long enough to remove the heat. Too fast no good,,,, to slow no good. We are supposed to be using antifreeze to help prevent vaporizing thus keeping the fluid right against the engines casting. It's just one of the components of a good coolant mixture. Another is raising its boiling point higher than that of ordinary water. We also control boiling points by allowing the system to become pressurized. The higher the pressure the higher the boiling point. This is how closed loop systems have become the norm for almost all types of cooling apparatis not just the automotive world.
I'm done on this one......

 

[daredevil]

My reasoning is a stock pump isnt going to move the water to fast for it to transfer heat and once the thermostat opens it stays open. Its not closing to let the hot water have time to cool. I followed the herd on this one for 30 years but in the last few I have experimented some myself. I,m not gauranteeing i,m right just that this is how it works in my application. I,m also done. Lets figure out the ops problem.

 

[daredevil]

My 500 ran warm with a shroud and clutch fan and i tried everything. Restrictors, different temp stats and checked hoses added water wetter and used 20% antifreeze cause water dissapates heat better. Still ran warm and would creep to hot. On a tip from a machinist friend I bumped total time to 40 or 41 degrees. Motor runs about 190 now. Its over 90* outside now so I think thats good. This bumped my initial up to about 24 but it starts ok so i,m happy. Throw some more timing at it. Your mechanics probably right. Fuel is still burning past the exhaust valve causing more heat in the block. Maybe if your cam has a lot of overlap its leaning out your intake charge. It cant hurt as long as you dont run it detonating,pinging.

 

[poulinpro]

Thanks everybody still trying to solve problem thanks for all your input I take it all in even the negative help is help!! just a thought they (griffen) sent me a cap with radiator how do i tell if it is the right pressure?? would that make it overheat I just looked no numbers on cap whats the correct pressure cap for 440hp???

 

[62MAX]

You should have a 16lb. cap