Overheating 454....any ideas?

454 cooling problems!
Bottom line is Im restoring a 73 Nova SS that was setup as a
1/4 mile car.....I have already changed things up from the original config to address cooling.

Current engine specs:
- 454 bored 30 over
- Compression 12:1

- Cam: Intake duration at .006 lift is 300 and intake duration at .050 lift is 240 lift at cam is .330 - lift at valve is .560 - intake centerline at 110 and lobe sep. angle at 112

- 373 rear gear
- MSD ignition

- Holly 850
- Edelbrock intake
- Hooker headers
- 3" Flowmasters

- Griffin 31x19.5 alum radiator (50/50)
- 16" Pusher fan on front of rad. (17cfm)
- Mechanical flexfan pulling (no clutch)
- Replaced thermostat w/160 (also tried just restricted)
- Replaced gauge cluster and sensors
- Water pump pumps great!

PROBLEM:
Car runs fine at speed 190dg at 45mph, 200-205dg at low speeds. And generally climbs up to 210-212 at long stoplights.....
then comes back down again with speed.
HOWEVER,....it does continue to get hotter and hotter at idle....
if I got stuck in traffic I would be in DEEP trouble as the gauge will get to 230 at about 4 minutes of idle...then I shut her off.
I am running 93 octane and an octane booster.

ISSUE: 1ST SHOP that messed with her set the timing waaaay back. (dont ask me why)

NEW race mechanic wants to do following:
1) Set timing where it SHOULD BE
2) Lock out distributer
3) Install 'starter saver' for easy starting with locked timing
4) Fill radiator with water and Water Wetter...no antifreeze (I
am in Florida)

5) I then run 3-5 gallons racing fuel with 11-12 gal 93 octane premium.
Racing fuel has lead,.....he also mentioned that helps with the cooling.

He said the car will then not get increasingly hotter,....it will reach a point...but not continue to climb indefinately.


Any opinions on this situation,......Im not looking for a daily driver out of it.....but jesus...there has to be a reason it just gets hotter and hotter and hotter......and I feel the cooling system is pretty much maxed out...

thanks!

First off, the higher octane fuel will have little effect except will allow you to run the timing where it sounds like he wants to go. That can help some on cooling. The lead comment I won't even address, but I am shaking my head.

Now for a real fix. Get rid of the pusher fan, and since you didn't mention any other form of fan I guess that's the only one. There's a clue in your description. Notice that it ran hotter at lower speed than higher speed. That's because the pusher fan is BLOCKING air flow. The high paid engineers that build these cars originally always try to have the fan on the back of the radiator if they can. Also, using the OEM's for guidance, a shroud around the fan (either mechanical or electric) draws ALL the cooling air through the ENTIRE core. Make sure there are no gaps around the outside of the radiator where it fits to the core support. And if the car originally had a rubber strip across the top of the core support to seal to the hood when it's closed, replace that if it's missing.

BTW, thanks for giving a thorough, well thought out question and information. It makes it a lot easier than the guy who pops up with "My car runs hot, what do I do".

Hey Streets for us poor old Arizona boys could you define what "HOT" is in NY :toocool:

Yes, the timing does affect the temp.

Yes, I firmly believe the shroud helps that much. The reason the pusher
helped your situation is that you are compensating for two other problems.
First the fan. When you say "flex fan" I picture one of those flimsy,
aluminum blade (shaped something like an elongated tear drop) fans that were
popular 20 years ago. They're junk!! 17" sounds like a good size, notice
that the factory fans are more of a "square" or rectangle shape, and have
some flexibility. These are much more effective. Second, your fan is too
far back to be effective. It should be about 3/4" to 1" back from the core,
not 3". For the shroud to work with the fan effectively, the fan pitch
should be 1/2 to 2/3 into the shround. If the shroud you are getting from
Griffin doesn't have it, you might want to make provision for high speed
cooling. You might have seen on OEM shrouds where there are "windows" cut
in the shroud with rubber flaps over them. At idle the pulling motion of
the fan keeps these flaps closed allowing the fan to pull air through the
full core. At high speed (freeway say) there is enough ram effect from the
air coming through the grille that it "blows" the flaps open to allow more
flow through the shroud.

Whether or not you have other problems is hard to say from here. But with
all the stuff you've described so far I would suggest fixing those issues
and seeing where you sit then before trying more diagnosis. Process of
elimination of the most obvious you know.

Bob,...
It is not a teardrop antique fan....it is a typical 17-18" 6 blade
'flex fan', aftermarket.....it had slightly curved, flexible, rectangular blades mounted to a black anododized frame....however the shroud scenario you mention is far from my current setup...
the distance from blade to radiator is apprx 2.5-3". The distance from blade tip to shroud is apprx 4-5 inch. The amount of coverage of blade from shroud is about right,...but the shroud itself covers only about 80% of the radiator and is not flush to it....there is a 1/2 gap down the left side......

All this will be rectified on monday with the arrival of the proper shroud from Griffin for my radiator.....

I would assume the mechanical fan alone should be sufficient at idel to pull a towel towards the grill (mine does not at all). Ofcourse, with the electric fan on it will suck a 4lb beach towel to the grill and hold it there :-)......(still rising heat though :-(

Just something to think about, How many pounds is your radiator cap? Something that small might of been over looked

One other thing about the shroud I forgot. The hole for the blade should clear by 1/2", so an 18" hole for a 17" blade for example.

Bob,....thx on that size info. It will all help monday night when I install the shroud......

Awsum....not 100% sure on the cap....but I do not have any overflow problems....I am not 'overheating' yet.....the temp does just keep rising at idle though......I shut her down around 230...I do not want to experience overheating.....I just want to know the 'ceiling' when she will stay at a certain temp without rising anymore......BUT I will check on the cap.....or get a new one....
What psi should it be?????

Email between Mike and I:

Hi Again.

1. You do not necessarily need a clutch on a fixed fan, however it in addition to the reasons I mentioned in the post (i.e. HP loss, and noise), it is also easier on the water pump pulley especially at high engine RPM, where any imbalance in the fan is magnified. Additionally, fans designed to run with a clutch generally have a steeper pitch than fans designed to run direct. This results in their being able to pull more air when the clutch is locked than a normal direct drive fan.

2. Absolutely. Unless you have a fan I haven't seen before (I read your post were your explained the fan you have, and I know the fan your referring to) the aftermarket units flatten out at a lot lower RPM (even a little at Idle) reducing their effectiveness. The Ford fans have a little steeper pitch, and are made a little stiffer, which is why I would use one of those over the aftermarket type, if I couldn't run a clutch.

3. A good shroud is CRITICAL, I didn't spend a lot of time addressing this as Bob had already pretty much covered it. All of the cooling system components must work together, a good fan AND fan shroud should make all the difference in the world as far as cooling.

4. The "Tricks" your mechanic mentioned are RACE CAR ONLY things, that are NOT RECOMMENDED for street driven cars. A car that only see a 1/4 mile at a time require different things than car that is used to go up and down the street. My main concern is that he recommended things that will only make a very insignificant impact on the cooling problem. After the timing was set correctly and the car still overheated, he should have quickly diagnosed the likely problem as the fan/fan shroud/electric fan and explained this to you rather than trying all this other stuff. Chances are when this didn't work, you would have still been down to putting a fan and shroud on it. By the way were you going to have him put the shroud on at the same time he did this other stuff. If you were the shroud would be what would make the difference, not the advance limiter and then the starter saver.



PS Als suggestion about checking the radiator cap is a good suggestion and example of that I just said.


Mike

Thanks to all who are offering advice,....I am trying to get everything sorted out as best I can before I take the care to 'new' mechanic on Wednesday.

MAIN PROBLEM: car temp rises steadily at idle. Have not overheated yet.....but I shut her down at 230. Has NO problem running at 25-50mph...stays around 200-205 tops.

Shop 1 (last week): Replace 480? rear gear w/373. New torque converter and installed Griffin 31"x19.5" radiator. They ALSO set the timing waaaay back. I do not know how far....I do not know how to check this :-(

Result:This helped some.
At Idle car would not draw a towel towards vent.

I ADDED 1700cfm 16" pusher fan on front of radiator, added new
gauge cluster and sensor and put in 160degree thermostat (did not have one in there before??). Car also has 18" 6 blade flex fan and crappy ill-fitting shroud.

Result:This helped ALOT and car easily pulls towel at idle and runs much cooler. I feel comfortable driving around evenings as long as I dont sit too long......

I have called a new shop and have an appt for this wednesday.
The new mechanic who has not worked on the car yet wants to set the timing back to 'proper'. He says the backed off timing is causing the heating up. He also wants to lock the distributer and install a 'starter saver' AND drain the radiator and fill with water only and water wetter. He says I must run a racing gas mix to prevent detonation as well (fine with me).
I HAVE NOT HAD the above work done yet.

On MONDAY (2 days before above work is scheduled) I will install the proper shroud, and hopefully a good solid pitched blade as well.

I am still searching to determine if the set back timing is causing the heat......IN ADDITION to the fact I do not have a remotely adequate shroud or good solid pitched fan for that matter.
AND if locking the timing will cause me TROUBLE or not.
PERHAPS I should just have him set back the timing to normal, and NOT lock the advance?????

Again,...thanks to all and anyu further advice will be MUCH, MUCH appreciated!

Jeff Dobrow
"new,....but learning"...
btw - Pic of the troublemaker is in my photo gallery now :-)

16 lb cap will do, Like what was said earlier, timming running lean will cause you to run hot, Just something else to think about, you might have to rejet the carb.

Here's a link on over heating you might enjoy:
www.inccn.net/techforum.htm

Doc,
One more thought I forgot. We're all assuming your gauge is giving you an accurate reading. If it is connected with a single terminal sensor, make sure there is no thread sealant (e.g. teflon tape, or plumbers dope) on the sensor.

I just replaced teh gauge and sensor....and no tape on it. Actually, it appears to be a little better that the previous gauge by about 5 degrees HOWEVER the problem is climbing heat levels...not really about an absolute temperature.

REMEMBER,...the car will continue to climb at an idle,....I do not let it go past 230....but currently I am sure it would just rise and rise and rise.....so whether the gauge is 10 degrees off or not really doesnt matter....what matters is the constant rise in temp.
If I KNEW the car would sit and idle at 230 I would have no complaints,....I know BB's run hotter than most,....but this darn constant rise is the problem!

BOTTOM HOSE is tight as a drum. Good and solid.

All I can hope for is 2 things:

1)New proper shroud that actually fits will help or cure.

2)Setting the timing to its proper place will cure. (pray, pray, pray)

3) Going to 100% water and water wetter in radiator will help.

Something I have not mentioned,....and am not too knowledgable on (yet)....is the seperate trans cooler my car has. It is a blade type,....like a small radiator....and it is mounted in front of the left side of the radiator. It has about 1-2 inches clearance to the radiator.

Is this a bad place for it to be? Is it contributing to a lack of flow?

Where else could it go? I assume it needs to benefit from ram air effect and should somewhere behind the grill of the car? (where the radiator also is).....

Any ideas? or os this fine and dandy....?

My transcooler does NOT attach to my radiator in any way...(as far as I can tell).....

And it is mounted on the far left quadrant (far as It can go) of my grill/radiator area.

Proper shroud arrives today (wish me luck)!

Any tricks involved with installing a new shroud?....

Well, one more thought. Don't accidentally drill through your core when mounting the shroud. Sounds obvious, but.....................life happens.;)

OK...do not drill hole through core,.....do not drill hole through finger either....:-)

Almost ready......a few more questions:

I have figured the best way to do the shroud is as follows:

a) Remove radiator
b) Slide shroud in place over fan
c) Put radiator back in
d) Fasten shroud to radiator

My QUESTIONS are:

1) When I drain the radiator,....some 50/50 will still remain in
the block. When I refill Im going 100% distilled water with water wetter.
Will the 50/50 in the block cause problems? OR HOW DO I DRAIN it as well???

2) My new super-cool shroud will cover the fan blade. It is an 18" hole for a 17" fan which is good,...but it will extend to the back of the blade.....not overlapping,....but covering. WILL THIS CAUSE A
PROBLEM with the suction?.....I know according to earlier advice it should overlap....but their simply is not room for this.

Thanks again guys,....this is basic stuff I know....but i'ts not basic to me! I just don;t wanna pay $75 to have this done,....it should be doable in my garage at home!

Well, most everything has been covered here. A couple of other "tricks" if everyting else fails: I've seen temp reductions by additional oil cooling (up to 40% of engine heat is dispersed by the oil). A good sized remote oil cooler equipped with an electric fan & running a straight 30 or 40 weight oil can be a big help. A remote trans cooler (away from the radiator & equipped with an electric fan) can also help. I run these on the 55. Get as much hot air as possible out from under the hood (convection) by venting or removing the hood completely. There was a fellow in Phoenix that manufactured auxillary radiator cooling units out of copper. These units were long & skinny & could fit under running boards, along frame rails etc. ... they worked great! ...Good luck!

Thanx dyno!
I already have a seperate trans cooler,...it is mounted on the front though......at a worst case scenario I guess it could go along a fedner wall with a fan attached....but that would use alll available space.....(ie no room for oil cooler)....

THe shroud turned out to be a real %$#%$! to install as there is little room between the water pump, pulleys and radiator. I had to knotch out some areas of the shroud to accomodate pulleys...etc...etc.

My only concern and SOMEONE PLEASE tell me how much this affects things is that the shroud totally overlaps the fan by about 2 inches. It does NOT cover 2/3 of the blades....but totally envelopes them by 2 inches or so.....otherwise it is a beautiful tight fight covering the entire core...and tapering up center to just behind the fan blades. The blades have about 3/4 to 1 inch clearance in the shroud.

Prior to this shroud I essentially had no shroud,...just a 3 inch lip that covered about 75% off the core, and had a totally open bottom...virtually worthless.

Doc,
You have a digital camera or a scanner? Like to see what you're dealing with.

BOB, and all.....I have posted pictures in my gallery.....

The shroud is on. Good tight fit around entire core. As I mentioned above.....it does cover the fan. No choice as far
as I could tell.

I took it out for a test run,...midday (HOT!) and in alot of traffic, stop and go it got to 220. It wanted to quickly calm back down once running again. It does seem to run cooler now. The shroud is definately helping.....but I fear it (more driving will be done in a bit)....will still keep rising.

I am banking everything on the fact that the timing is set too far back and this is the underlying source of the 'rising' heat. If the
timing is set proper, and I run race fuel with water/water wetter in my radiator and the temp still climbs I will have NO IDEA what to do next. Probably put her up for sale....and buy something I can drive :-)

It's a little hard to tell from the picture, but you might be able to pull the fan back a little by using a little shorter spacer.

Let us know what happens when the timing is set.

Personally, I would go with a clutch fan if what your doing dosn't cure the problem before I sold the car.

BTW it is a very nice looking car (always did have a soft spot in my heart for sleepers).

thx...it is quite the sleeper. 73 Nova,...no markings at all except for the SS on the front grill,.....and apprx 500hp. Ofcourse, the 235/60's on the back won't let any of it to the ground.

I examined the spacer scenario,....and yes it possibly could go back a little,...but not much due to the pulleys......even with it moved back say 1",....the shroud would still cover the fan.

I guess that issue lays with the fact its a big engine in a small compartment.....?

Well now, those pics help. I'm with Mike on the spacer thing. And yes, you're probably right about the longer engine, or at least BBC's having the long nose pump. Now that I see the trans cooler, I would suggest you move that too. The hottest water is at the top of the rad, and that trans cooler looks like a big one. Not only is it dropping additional heat to the core, it's also blocking air flow. And there's still that front mount fan. Was it running when you did your test? If so, imagine it as a wall when the blade spins. That's a bit of an over statement for effect, but it is blocking flow. The fan being so deep in the shroud is reducing it's effectiveness, so anything you can gain there will help more. It looks like the pitch on those blades, from what I can see of it, is pretty steep. If you can see some oem fans like the clutch units Mike is talking about, I would guess they have a flatter pitch which should allow you to get further back before interfering with the belts/pulleys. It's too late given the mods you had to make, to return it, but it may have been worthwhile to see if the manufacturer has a shallower shroud. I'm real good at hindsight, 20/20 in fact.:)

BTW, if you decide to shed the car, keep those Cal Custom covers, they look to be in pretty good shape.

1) The electric fan reduced the temp by about 15 degrees when I put it on. I see your point,.....but are you sure (in your opinion) it is hindering me?....especially at idle when the heating issue occurs?....doesnt it maintain constant airflow into the radiator and into the puller fan?

2) The trans cooler...where else can it go>? Doesn't it need ram-air effect as well as the radiatior?.....Can I stick it off a fender wall? Should I try and lower it?....Putting it over the bottom part of the radiator? Any suggestions?

3) Yes,....I suppose in hindsight the fan/shroud setup leaves something to be desired,....but man what a pain to put in on.....I will investigate this further if tomorrows work does not pay off.

4) Wouldnt a flatter pitch fan draw less air than a more aggresively pitched fan?

5) BTW - This was the only shroud Griffin said was available for
there 31x19.5 inch generic alum. rad. Thats what the said anyway,....probably could get something custom made...$$$ :-)

Tonite,...lets all pray in unison that tomorrows endeavors pay off:
1) Set timing properly (no locking the advance)
2) Fill radiator with distilled water and water wetter.
3) Run a mix of race gas and 93 pump gas

If this stuff does not work.......ANY IDEAS ON WHERE TO LOOK
NEXT FOR THE PROBLEM????????????????

Dr_Jim, I agree with Bob on the tranny cooler, My old Nova and camaro had the tranny coolers at the bottom of the radiator, Neither had problems with overheating, Then again I wasn't running a BB. But I would look at lowering the tranny cooler to the bottom of the radiator. That and removing the electric fan, then take it out in a non congested area and see what the temp does, Imitate rush hour traffic by stopping and going slow. In the non congested area you can at least pick up speed if it starts going over 230*.
I would check this stuff before spending more money on the fan and shroud.
But definately get the timing set properly, try a lighter mix of antifreeze/water, I would say 30/70 anti/water. I personally don't like running straight water, went 30/70 in the mojave desert in my camaro and never had a problem with over heating except on my runs to Vegas through the hills where they recommend you run your heater to cool it.
I like a little antifreeze in so the water doesn't boil off if it does get too hot. Not sure if it can, but thats my thinking.
Good luck with the car. Hope our thoughts can help you fix it.

Yeah,....lowering the tranny cooler could help. And not a big job to do it either. HOWEVER,...there is a metal frame panel that covers about 4 inches of the core on the left side anyway....it is simply how the car was built,.....and this is a big %^% radiator....the tranny cooler is seperated from the radiator partially by this metal framework.......

As far as the fan goes,....I will re-iterate....I did not originally have an electric pusher fan.....when I ADDED the fan the temp dropped 15 degrees. I fear if I remove it....it will heat up more (like it did when I got it.....). I do NOT mean to be argumentative to those who know so much mroe than I.....however an explanation of why it helped so much,....and now to remove it would go a long way with me. I need logic here. I know it is like a wall in a way....however it is a wall that is sucking in air at 1700CFM and pushing it through the radiator into the mechanical puller fan...so how is this bad?....And doesn't it make sense that if adding it reduced cooling by 15 degrees that removing it would cause temp to rise???

I have been advised by 'many' people to NOT use antifreeze at all....just water and a water wetter.

????????????????????????

Streets.your temp dropped from 235 to 190! Thats what im talkin' bout! :-) (Jeff is hopefully smiling)

The heater core is gone. So that is not an option.

Lowering compression is not an option either....$$$$

Hood off?....nahhhhh :-)

Gonna run race fuel though.....

I've got about 16K total in her including purchase and all my restoration......I'd need to get AT LEAST that back.....
With the way Hollywood is using muscle cars these days in all
the cool movies,......Im sure in 6 months some rich kid will DIE to have a 500hp blacked out Nova....:-)

btw - Has everyone noticed the return of the muscle car in alot of the summer blockbusters? Charlies angels? Bad Boys II?..FF2..etc...etc....even TV commercials. Im tellin ya,....our cars are appreciating as we sit....

Point well taken......

My engine and compartment are too ugly to go topless right now....

As for the tranny cooler.....can it go somewhere else in the engine compartment?.....DOES IT NEED RAM AIR? oR CAN I
put it anywhere it will fit?

As for the trans cooler, lay it down at the bottom of the area in front of the core support, or move it outward (toward passenger side), cut a hole in the core support behind it for flow.

One problem I have with your three step remediation plan is, if one of them "solves the problem" the other two are a waste of time and or money since you won't know which one did it. You end up incorrectly believing it took all three to accomplish your objective.

Be systematic. Resist the "throw a bunch of "stuff" at the wall" syndrome. As for the electric fan, it was a crutch. If you "heal" the problem a crutch becomes a hinderance.

Bob - You are correct.

Due to the fact the work is scheduled..and I did remove the "lock the advance" from the agenda.....I DO want to run water in the radiator,....and you as well as everyone confirmed that the timing should be set correctly.
As far as the race gas goes,.....I assume it is necessary if the timing is set properly due to the nature of the engine (see 1st meddage in thread). But you are right in that I am throwing 3 things at the situation......at this point I am just so frustrated,....I would rather do that than further a systematic approach. And the cost for these 3 things is very negligable.

You are right about the fan,....it is a crutch. If the car does not lean towards overheating after tomorrows work,.....I will try it without the fan. (Even used,...AdvanceAuto said they will take it back if I am not satisfied up to 30 days!....)

Trans cooler: I dont follow you Bob,....should I just move it laterally towards passenger side from where it is at? and perhaps down as well?.....it does need to stay in front of car though correct?....I cannot mount it inside the engince compartment mounted off a fender wall or such right?......

Thanks for all your help,.....and everyone elses,.....tomorrow morning the timing will be set...etc...etc. I will post the results tomorrow!....

pray.

Re; trans cooler............yes, keep it in front of core support. Lower would be better. If you've got room mount it horizontally, I'm thinking of it in it's current position as vertical.

Streets - It will 'run' on the road at about 190-195degrees. Probably 190 if its not 95 out. Its just after sitting at a few lights it wants to climb and climb and climb......after a 4 minute idle in the driveway it can get to 230. I shut it off there,....do not know how much higher it would climb......

As far as the hood goes,....honestly I would not like the look of the car without the hood. Just does not work for me.....

They make relatively inexpensive after-market cowl induction type hoods....which would allow for flow,....or I coud have vents installed in this one......its and idea.....

And BOB,....the cooler is actually horizontal....its about 12x7 inches or so........

YAAAAHOOOO!!!!!

It is fixed!!!!....it is fixed!
The timing was set at 0. It was set proper at 36 and the car idled for 30 minutes at 190. I drove it to work in traffic and it never got over 192. Yeaaaahh!!!


A big thanks to all!!

I will now try a race gas mix and see if that does anything?...

thanks again! I will not have to sell her now!

:3dSMILE:

Return the electric fan.

Bob,
You are a funny guy! :-) And I truly appreciate all your help!
If I can ever return the favor with my expertise in design/marketing let me know!

Yes,...tonite I will remove the fan and take it out for a run.
Assuming the temp stays low......I will return the fan and use the $70 to take the wife out to a celebration dinner.....

Dr Jim, congrats on getting it to work, I am glad all worked out for you.

Well so much for picking up a cheap big block Nova. I'm glad you got the heating resolved.

This thread is likely to die out now, but I thing Bob made a very valid point about taking a systematic approach and doing one thing at a time to diaganose and fix a problem.

The only thing I would add is that when the frustration level builds to the point it must have with you (and believe me I can relate). Sometimes, it is best to walk away from a problem for a while and then take a fresh look later. A lot of time it actually saves time and money.