how hot is too hot

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Optik

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whats the best range for a warmed up 360 to operate at? i'm sure 180* is probably ideal for most any 70's v-8 motor, but mine starts to run funny over 170*. if it hits 180/190 it starts to bog and then if you take it out of gear sometimes the idle will run up to around 1000rpm where it would normally idle around 700-750 when in neutral.
this car has a fairly lumpy cam 233/233 @50, .512 lift on a 114 (i ithink) LSA. the cam has been degreed and it likes around 12* of timing at idle with 34* all in at 3000. MSD ignition, stock '77 360 heads with EGR ports plugged, shortie headers, holley street dominator intake, edelbrock 600 carb. it has been dyno-tuned as it sits right now but it just wants to act funny as soon as it gets a little warm at all. running a 22" stock mopar downflow radiator recored with a high-efficiency three-row core, running a flex-fan with a 1/2" spacer and a chrome cheapy half-shroud and a full-time electric pusher fan on front of radiator. the one thing i didn't do was trim the coresupport opening to fully expose the radiator. i'm covered on maybe 3" of a side by the core support.

any suggestions to improve driveability (oh yeah, it IS a daily driver.)? i mean, really the thing has been super-reliable and driveable while still making enough power to get in trouble with but i would like the peace of mind of being able to run it around even on the hottest days and not worry about having to sit in traffic. or am i just expecting too much of a souped-up old car?

thanks
-Tim
 
A couple questions, what stat is in it now, how far is the fan from the rad., and what pump are you running.
 
camd64 said:
A couple questions, what stat is in it now, how far is the fan from the rad., and what pump are you running.
Click to expand...

160* thermostat
stock replacement water pump
fan is approx. 1" from radiator with a short shroud allowing about 3/4" of the fan blade exposed,
 
the flex fan might be part of it but im also thinking you might have some fuel issues. do you have the thick gasket under the carb. and also look if any lines are close to a heat source.
 
run funny after 170? hmm im putting a 180 stat back in mine.. I like mine to run around 180-190 200 max
 
I have a 360 bored .030 .474 cam with 10.7 compression and been having cooling problems. My fuel line or something fuel related has been so hot that it vapor locks and the idle goes up because the carb starts running lean. I switched to a 160* from a 180* thermostat and it made things worse. I have a 2 core stock radiator now but I've got Griffin building me a new radiator. I would get out on the hwy and it would get in the 210* range and start wanting to shut off and act funny (vapor locking). I've got a shroud coming also and going to try all different type things. Even a electric fan in front of the radiator used as a pusher. Until I get everything installed I won't know anything but I know what I have isn't working. So I find this thread interesting to say the least.
 
camd64 said:
the flex fan might be part of it but im also thinking you might have some fuel issues. do you have the thick gasket under the carb. and also look if any lines are close to a heat source.
Click to expand...

i have an aluminum carb adaptor on the manifold to mount the edelbrock carb and stock fuel lines, hard line coming from the mechanical fuel pump to carb. it is also hard to re-start if it gets too warm but not like its blowing huge clouds of black smoke or anything.

i would like to re-emphasize that its not really running HOT by any means, but runs great when cold or cool but once it gets to normal engine operating temps it starts to act a little funny. sometimes idle speed will start to creep in neutral if its warmed up.

last summer i found it behaved a little better with the vaccuum advance disconnected but liked it hooked up in the winter.

thanks for the help so far, please keep the suggestions coming.

-Tim
 
I would loose the aluminum adaptor and try a pneumonic one that will not transfer heat.. sounds like the carb is getting to hot. I had the same problem and a pneumonic type fixed the problem.
 
yeah put one of those thick heat barrier gaskets under the carb. the holley carbs are a little better for that reason as they don't have the fuel bowl sitting right on the hot manifold. I had the same issues with my edelbrock and the gasket fixed it. even though you have the adapter its aluminum so it transfers all the heat to the carb. also if the air cleaner setup is low down to the manifold that will draw in heat and keep it around the carb. like an air dam.
 
mullinax95 said:
I have a 360 bored .030 .474 cam with 10.7 compression and been having cooling problems. My fuel line or something fuel related has been so hot that it vapor locks and the idle goes up because the carb starts running lean. I switched to a 160* from a 180* thermostat and it made things worse. I have a 2 core stock radiator now but I've got Griffin building me a new radiator. I would get out on the hwy and it would get in the 210* range and start wanting to shut off and act funny (vapor locking). I've got a shroud coming also and going to try all different type things. Even a electric fan in front of the radiator used as a pusher. Until I get everything installed I won't know anything but I know what I have isn't working. So I find this thread interesting to say the least.
Click to expand...

My 340 is bored .060 over and I don't know what the compression is as I
didn't build it, however my cylinder pressure is 195 which is pretty stout
and I run a rock solid 180 pretty much all the time, really hot and in
traffic 190 and I also have no shroud.
I Increased my
initial timing and it lowered my temps over 10 degrees. I Don't know about
aluminum radiators, but I do know US Radiators makes a killer set up. They
can make a 2 3 or 4 core unit, aluminum radiators and one the call the
desert cooler. I think I paid about 230 for mine. It's nice and other than the
part number and pentstar, it looks stock.

FWIW
 
I have an eddie on my 318 cop car and had much the same problem with eratic idle and hard hot starts.

Heres what to do;Run the motor till it's up to normal operating temp. Shut the engine off,pop the hood and remove the air cleaner housing. Listen closely to the carb. If you can hear frying/sizzling sounds,that eddie is too hot!

To compensate I put in an aluminim spacer.In between the spacer/manifold is a thick 1/4 gasket. In between the carb and spacer is another 1/4 gasket. If this doesnt help your situation,you will need a composite spacer of some kind. Insulating your fuel line may help as well.And someone here mentioned a black fuel tank as being a bad idea,as the black color would soak up heat.

The pair of 1/4 gaskets has the added benefit of increasing your plenum length by 1/2 and is cheaper than buying a composite spacer.Maybe give that a shot before bucking up for the fancy spacer.
 
It seems like the gas is boiling inside your fuel system, If you know someone that has a another carb try it , check fuel lines , keep them from heat source , you may try a holley carb they are less prone to vapor lock
 
idrift said:
My 340 is bored .060 over and I don't know what the compression is as I
didn't build it, however my cylinder pressure is 195 which is pretty stout
and I run a rock solid 180 pretty much all the time, really hot and in
traffic 190 and I also have no shroud.
I Increased my
initial timing and it lowered my temps over 10 degrees. I Don't know about
aluminum radiators, but I do know US Radiators makes a killer set up. They
can make a 2 3 or 4 core unit, aluminum radiators and one the call the
desert cooler. I think I paid about 230 for mine. It's nice and other than the
part number and pentstar, it looks stock.

FWIW
Click to expand...

Friend of mine let me borrow a US raditator to try and make it work. The bottom outlet was on the wrong side but other than that it fit. I wasn't to happy about running a hose across or near the crankshaft pulley. I know I could have without problems but just went ahead with a Griffin. The US radiator looks like a well built radiator that's for sure.
 
mullinax95 said:
Friend of mine let me borrow a US raditator to try and make it work. The bottom outlet was on the wrong side but other than that it fit. I wasn't to happy about running a hose across or near the crankshaft pulley. I know I could have without problems but just went ahead with a Griffin. The US radiator looks like a well built radiator that's for sure.
Click to expand...

Wow that's weird the bottom outlet was on the wrong side, I think there was
a year change on A bodies but I could be wrong. The only botched thing
on mine is the overlfow tube is on the wrong side, but thats not too bad.

I looked at Griffin but caught US when they had a sale and I got 20% off
so that was the deal maker for me.

Let me know how you Griffin works out, I know they make a nice piece.
 
idrift said:
Wow that's weird the bottom outlet was on the wrong side, I think there was
a year change on A bodies but I could be wrong. The only botched thing
on mine is the overlfow tube is on the wrong side, but thats not too bad.

I looked at Griffin but caught US when they had a sale and I got 20% off
so that was the deal maker for me.

Let me know how you Griffin works out, I know they make a nice piece.
Click to expand...

It was for a big block car.
 
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