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rrconductor
Buffalo

USA
59 Posts

Posted - 01 Aug 2015 :  8:22:51 PM  Show Profile  Reply with Quote
My problem is my engine temps climb when running 65-75 mph on highway.Here is the facts of what I have and done,Pontiac 350 bored .030,timing set at 10 degrees initial 36 all in,flowcooler water pump with divider plate clearanced to specs,160 t-stat,aluminum 4 core radiator,new 15 lb radiator cap,16 inch electric fan with shroud and flaps for highway speeds,all new hoses-lower hose has spring,vintage air but haven`t used it because of the temps climbing,I have all rubber in place and all baffles in place.All parts are new and the temps are at 185-195 when cruising at 50 mph or lower even in traffic.I have a 8 inch crank pulley and a 6.25 water pump pulley,power steering.Any ideas would be appreciated.

cortcomp
Coyote

USA
5338 Posts

Posted - 01 Aug 2015 :  9:01:27 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
Is 185-195 as hot as it gets? If so good job and no worries! Also see if you can get that initial from 10 to like 13-14, made a big difference for me!
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rrconductor
Buffalo

USA
59 Posts

Posted - 01 Aug 2015 :  11:09:34 PM  Show Profile  Reply with Quote
No,the temp gauge continues to climb at highway speeds 65-75 mph,will get to 220 before I pull off and slow down then the temp will go down.Cruising at 50 mph or lower or in traffic the temp only gets to 185-195.
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GtoGuy32
Cochise

USA
842 Posts

Posted - 01 Aug 2015 :  11:19:15 PM  Show Profile  Reply with Quote
What engine RPM are you at?

My engine runs at 170-175 in normal driving and goes up 5-10 degrees when I run it at 3000-3500 rpm on the highway.

I think the more revs under load are going to naturally create more heat. Your cooling system is able to dissipate heat at a given rate and your highway driving is far exceeding it (obviously)

Do you have a radiator overflow that will allow expansion and then pull back into the radiator during cooling?

Is the 160 T-stat a high flow or regular style?
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cortcomp
Coyote

USA
5338 Posts

Posted - 01 Aug 2015 :  11:54:20 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
running lean maybe? I had similar, adding initial timing dropped me like 20 degrees, but that's not everyone's good result.
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Bill Boyle
Horse Feathers (Charter Member)

USA
4797 Posts

Posted - 02 Aug 2015 :  08:40:17 AM  Show Profile  Visit Bill Boyle's Homepage  Reply with Quote
Do you have a vacuum advance in play? You didn't mention it in your original post.

What is the temperature outside when you see this rise in temperature with your engine? Over 85, 90 or more? Do you have the same increase in temperature when it's later in the day and the air temperature is cooler?

How do your plugs look? Are they sooty black or grayish brown? What is their heat range?

What octane gas does your engine typically burn?

"Dedicated to keeping the classic Pontiac engine alive."

----
400 bored +.030, forged TRW pistons, ported 62 heads, Hedman headers, 2.5 SS dual exhaust X Pypes, Comp 276AH10 cam, Scorpion 1.65 RR, 850 Q-jet, stock intake & tuned HEI; original owner.
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rrconductor
Buffalo

USA
59 Posts

Posted - 02 Aug 2015 :  10:22:18 AM  Show Profile  Reply with Quote
The rpms are between 2800-3100,I am using 93 octane gas,I do have a vacuum advance and it does work,outside temps are between 85-95,cooler temps help some but not much maybe 5 degrees,plugs are burning light brown,don`t` really no the heat range,thermostat is a stant 160 superstat.When cruising highway speeds of 70-75 is when temp starts creeping up but if I shift to neutral and can coast for a little bit the temp starts dropping,real head scratcher.
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rrconductor
Buffalo

USA
59 Posts

Posted - 02 Aug 2015 :  10:25:42 AM  Show Profile  Reply with Quote
Forgot to mention that I do have a recovery tank.Do you think that the water pump could be turning too fast at higher rpms to allow the heat to dissipate adequately.
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Blued and Painted
Chief PONTIAC

USA
3409 Posts

Posted - 02 Aug 2015 :  11:03:24 AM  Show Profile  Reply with Quote
Cavitating? No. Could be bypassing too much coolant through the heater hoses. Some of the nipples at the back of the head are not restricted. Therefore bypassing coolant back to the water pump at the rate of a 5/8's garden hose wide open. The nipple or hose should be restricted to .250" to force more coolant through the radiator.
Then, the next time the intake or timing cover is off, restrict the intake to timing cover bi-pass.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.

Edited by - Blued and Painted on 02 Aug 2015 11:35:10 AM
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Blued and Painted
Chief PONTIAC

USA
3409 Posts

Posted - 02 Aug 2015 :  11:38:33 AM  Show Profile  Reply with Quote
if using an aluminum intake, many times the coolant crossover ports are restrictive and need gasket matching just like the intake runners.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.
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rrconductor
Buffalo

USA
59 Posts

Posted - 02 Aug 2015 :  11:43:11 AM  Show Profile  Reply with Quote
Yes the edelbrock performer I have had the water crossovers too small(3/4 inch around) I gasket matched them and honed them out to 1-1/8 inches.The nipple out of the passenger side head for heater hose is stock.
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rrconductor
Buffalo

USA
59 Posts

Posted - 02 Aug 2015 :  12:10:44 PM  Show Profile  Reply with Quote
One other thing is I did drill a 1/8 inch hole in thermostat and turned heater on and even jacked the front end up when filling the radiator.The radiator flows like a waterfall when the engine is revved up and cap off.Just seems weird that it only does it when the rpms go up.
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Bill Boyle
Horse Feathers (Charter Member)

USA
4797 Posts

Posted - 02 Aug 2015 :  3:01:28 PM  Show Profile  Visit Bill Boyle's Homepage  Reply with Quote
Electric fan. Is it a puller, on the engine side or a pusher fan on the outside of your radiator?

"Dedicated to keeping the classic Pontiac engine alive."

----
400 bored +.030, forged TRW pistons, ported 62 heads, Hedman headers, 2.5 SS dual exhaust X Pypes, Comp 276AH10 cam, Scorpion 1.65 RR, 850 Q-jet, stock intake & tuned HEI; original owner.
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rrconductor
Buffalo

USA
59 Posts

Posted - 03 Aug 2015 :  06:22:29 AM  Show Profile  Reply with Quote
Its a puller.
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Red Horse
Sitting Bull

204 Posts

Posted - 07 Aug 2015 :  01:34:29 AM  Show Profile  Reply with Quote
Hi guys,
Whats this about restricting coolant flow thru the heater core? My car has no heater , the hose runs from the rear of the head to the water pump. Should I remove this hose? Could it be contributing to my over heating in traffic ? Temps are running over 200 in stop and go, which we have a lot of here In Hawaii.
Rich
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Blued and Painted
Chief PONTIAC

USA
3409 Posts

Posted - 07 Aug 2015 :  09:23:31 AM  Show Profile  Reply with Quote
Therefore bypassing the radiator at the rate of a 5/8's garden hose wide open.

The outlet at the back of the head may or may not be restricted. Remove the hose and see if it has a small or large hole. If not restricted you can fabricate a pipe plug with a drilled hole and screw in into the heater hose, then re-connect. A small amount of bypass in needed for circulation during warm up.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.

Edited by - Blued and Painted on 07 Aug 2015 09:28:16 AM
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Brian R
Crazy Horse

USA
1672 Posts

Posted - 07 Aug 2015 :  12:50:31 PM  Show Profile  Reply with Quote
I have been running without the heater hose from the head to the pump for a dozen or more years and on 2 different engines with both stock #16 cast iron heads and Edelbrock aluminum heads. All engines were zero decked and used good polished pistons. It is not needed. I went through similar issues however.

Putting in the aluminum radiator made a big difference at idle, stop and go traffic, and around town. At highway speeds I had the exact same situation as you and with a 160 t-stat. Finally, I pulled the pump and found that even though I was told it was clearanced, the gap was too big. I bent and tapped the divider until it was just touching the impeller then backed off ever so slightly. You could just barely see light through the crack. With putting back the gasket, it was still nearly touching. Ever since then, no matter what I did with the 160 stat, stop and go, long highway rides at 3500 rpm on 90 + degree days, it always ran cool. Around town it ran too cold, right at 160. I actually went a step up to a 180 t-stat so it would run hotter. Now with the 180 stat, on a long highway run I sometimes get up to 190. Oh - the other thing I did was run a smaller fan pulley (increases fan speed) and a new clutch on the biggest 7 blade factory fan I could find - but - the clearance is what finally made it run so cool.

Are you absolutely positive that the divider was clearanced properly? My engine is a 461 with a Turbo 400 tranny running off the same radiator with no external tranny cooler in a 71 Lemans, no electric fans and the cowl is well sealed to the radiator.

If you are sure about the clearance, you could be flowing too fast through the radiator at high speed thus not giving the fluid time to cool down....but - I still lean towards the divider plate clearence.

Please give this write up I did (not overly well written but the facts are correct) plus it has a lot of additional good info posted by others on the board:
http://psp.aquacomp.net/topic.asp?TOPIC_ID=7410&SearchTerms=running,cool

Edited by - Brian R on 07 Aug 2015 1:08:17 PM
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2barrelpower
Sitting Bull

USA
135 Posts

Posted - 07 Aug 2015 :  5:58:14 PM  Show Profile  Reply with Quote
+1
I think some guys get it to touch and let the gasket be the clearance.

The clearance between the divider plate and the vane is more important than any other factor for a cool running Pontiac according to what I have read and experienced.

69FB, 350P, 9 to 1, Comp 260H, Stock Valve Train, Performer Intake, 1406 Carb, Hooker Headers, Points Style, Crane XRI, Crane PS20, TH350, stock stall, 3.08 gear, and 235/60/15 Firestones.
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rrconductor
Buffalo

USA
59 Posts

Posted - 07 Aug 2015 :  10:30:10 PM  Show Profile  Reply with Quote
Clearanced the divider plate myself using a piece of sheet aluminum the same thickness as the gasket against the water pump vanes.That does not seem to be the problem,the radiator flows a ton when the rpms are increased.Consulted with Butler Performance (they built my heads) and they seem to think the carb is not running rich enough in cruise mode or power mode going to change the metering rods a couple stages as suggested and see if that makes a difference,will let you guy`s know.Thanks for the advice,Allen
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cortcomp
Coyote

USA
5338 Posts

Posted - 08 Aug 2015 :  09:46:55 AM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
I wondered that up top, what kind of carb do you have? Cliff showed me where to adjust the APT on my q-jet, that's an awesome system, lets you dial in cruise, idle screws let you do idle mixture, and quick rod changes let you do secondaries. I don't see how it could be quicker or easier than an APT carb.
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rrconductor
Buffalo

USA
59 Posts

Posted - 08 Aug 2015 :  10:04:49 AM  Show Profile  Reply with Quote
Edelbrock 1406 (600cfm)pretty simple to change metering rods and springs and even the jets if need to.
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cortcomp
Coyote

USA
5338 Posts

Posted - 08 Aug 2015 :  11:01:02 AM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
If this is on a 350, i'd be surprised if a 1406 was lean out of the box, i ran one on my father in laws 454 and it was spot on, the AVS series was 2 steps rich. The 1406 on my 428 was spot on. (Just that secondary stumble everyone talks about.)

Did you try running more timing? With 93 you probably could get more, even with the XE series cams i got 15-16, but i did only have 9.3 compression. What heads and cam are you running? Not that it's the magic bullet, but on some setups, running retarded timing can really contribute to heat.

At cruise though vacuum advance should be all the way in and alleviate that, i'd just expect to see hot across the range? Kind of unrelated, but the flathead straight 8's like my packard were i think 5-6* BTDC. If you were like 2-4, it would add a TON of heat, and there wasn't a lot of margin in those cars before vapor lock or blowing coolant out settled in.
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rrconductor
Buffalo

USA
59 Posts

Posted - 08 Aug 2015 :  11:06:06 AM  Show Profile  Reply with Quote
47 heads built by Butler Performance at 48 head specs (larger intake and exhaust valves),cam is like the 067-068 grind can`t remember which one (have auto trans),9.2 compression,10 degrees initial 36 all in at 2500 rpm.
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cortcomp
Coyote

USA
5338 Posts

Posted - 08 Aug 2015 :  11:22:48 AM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
Just because it's fast and free, bump that up to like 14 and go for a drive and see what it does.

Carb tuning was easy for me because i had one of the AFR kits so you could get an instant read out to know where you were. There's lots of trial and error that takes experience that i don't have when tuning carbs by other methods.

I had a three cylinder/three carb bike that it took my a whole summer to tune the carbs on after intake/exhaust changes. ugh.
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rrconductor
Buffalo

USA
59 Posts

Posted - 08 Aug 2015 :  11:48:34 AM  Show Profile  Reply with Quote
Thanks I`ll try that and see what happens ,,I can imagine how much of a pain in the as? that was.
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tjs44
Cochise

USA
413 Posts

Posted - 08 Aug 2015 :  6:16:41 PM  Show Profile  Reply with Quote
Have you tried a lazer temp guage on and around you engine and radiator?Get one,see what the water temp is going into the radiator and out of the radiator.Check it at the water X over at the thermo housing and right where it bolts to the head.You can learn a lot without spending a lot.There should be a substantial temp drop from where it goes in to where it comes out of the radiator.Tom
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Brian R
Crazy Horse

USA
1672 Posts

Posted - 11 Aug 2015 :  09:34:33 AM  Show Profile  Reply with Quote
rrconductor: Any update? I am very curious on this.
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rrconductor
Buffalo

USA
59 Posts

Posted - 12 Aug 2015 :  3:16:03 PM  Show Profile  Reply with Quote
Have changed metering rods to 2 stages richer,made some difference,going to change primary jets next and see if there is any changes,just haven`t had time yet.Will keep you posted.
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loosetappet
Sitting Bull

113 Posts

Posted - 15 Aug 2015 :  2:51:53 PM  Show Profile  Reply with Quote
quote:
Originally posted by Blued and Painted

Therefore bypassing the radiator at the rate of a 5/8's garden hose wide open.

The outlet at the back of the head may or may not be restricted. Remove the hose and see if it has a small or large hole. If not restricted you can fabricate a pipe plug with a drilled hole and screw in into the heater hose, then re-connect. A small amount of bypass in needed for circulation during warm up.


The mustangs used to have a problem blowing out heater cores so they restricted the intake hose. Will a restrictor really lower operating temp by causing more flow through the radiator? Just curious if it worked for you.
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cortcomp
Coyote

USA
5338 Posts

Posted - 16 Aug 2015 :  11:01:23 AM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
I do know that the heater nipple that went into the head had a kind of spring that opened up as it got hotter. I'll try and find a pic.

Here we go:

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Blued and Painted
Chief PONTIAC

USA
3409 Posts

Posted - 16 Aug 2015 :  7:07:00 PM  Show Profile  Reply with Quote
Could be. My 670's has one like that.
Is it a deflector or does hi flow compress the spring at hi rpm's.


Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.

Edited by - Blued and Painted on 16 Aug 2015 7:14:23 PM
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cortcomp
Coyote

USA
5338 Posts

Posted - 16 Aug 2015 :  9:25:26 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
I think as it gets hot it expands, pushing it out the bottom of the nipple and letting more flow through, as colder, contracts up into the nipple and lets less flow though. If you push it all the way flat with your finger, almost the center hole in the spring coil is all that allows coolant through.
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rrconductor
Buffalo

USA
59 Posts

Posted - 04 Oct 2015 :  11:21:41 AM  Show Profile  Reply with Quote
Sorry I haven`t gotten back to you guy`s with an update,been very busy.I finally decided to try a different approach.I changed radiator out with a new 2 row 1.25 tubes with a dual fan and shroud from Portell Radiator near me,put the carb back to original settings,put in a 180 thermostat and checked the timing again.Took it out on the hottest day we have had all year in first part of September (99 degrees and humidity off the chart).The temp with the a/c on from the time I left my garage never got over 210 running 75mph for over 2 hours and never got over 190-195 cruising around at speeds less than 50 mph.I am very happy with those numbers.As of now when I take the car out with the cooler outside temps the gauge stays right at 185,so it seems right now everything is good.Thanks for all the interest and help,Allen
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