Thread: Overheating 454....any ideas?

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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?