Overheating issues

[fbodyjunkie]

I have a .040 454 8 to1 compression with BB2 heads, running a F-2 procharger. Right now it's on pump gas just for break in and to drive it around on the street to work the bugs out of it. Has a CSR waterpump, small restricter in it. Also tried with none in it and still same problem. Has 12 an hoses run to a Griffen Aluminum radiator(27x 16x 2 core), 2 12" stagger fans with shrouds. It has an interccoler in front of the radiator and a trans cooler. If I drive it from it being cold, I make it about a mile or mile and a half before seeing 220, any more driving without stopping goes right to 240. Would not think it should creep up that fast or not cool while driving under 3000 rpm's. Has antifreeze in it. Have tried lower timing( running it at 27 to 28 degrees total with this set up), richening the fuel mixture(C&S specialities carb) checking for good flow in the radiator and it has it. It is a new motor and I would have thought it would have ran cooler being low compression. Race gas just keeps it running cooler for a little longer then pump gas. What am I over looking? This was built more as radical street/ drag but the cooling issue would kill it at the drags too. For those that it matters to, the F-2 is set at 22PSI but doesn't do much at the lower rpms and is going through an air to air intercooler. Engine should make around 800-900 on a street tune and 92 octane and 1400 on a race tune and gas .I'm going to look at maybe a dead cylinder tomorrow as it only idles down to 1200rpms but runs smooth. Any suggestions would be greatly appreicated as I've ran out of ideas at the moment. Thanks

[ssym]

I have a similar issue with my SBC with 671. I can run all day until the outside temp hits 85*F. I figure that is the limit of efficiency on my radiator. If you have an infrared thermometer, measure the in and out temp on the radiator with the engine warmed up and running with the fans running.

I have a '66 Chevy II and can't install a bigger radiator without some core support modification.

[fbodyjunkie]

1970 Camaro here, and it looks as if the fans aren't doing squat. It will just continue to heat up the more it's run. They don't seem to move enough air to cool it down. Measured the face of the radiator it's actually 27 X 17. Whats the best fans or setup to put on it to cool it? 2 12" fans aren't near enough to cool it.

[dparker]

1970 Camaro here, and it looks as if the fans aren't doing squat. It will just continue to heat up the more it's run. They don't seem to move enough air to cool it down. Measured the face of the radiator it's actually 27 X 17. Whats the best fans or setup to put on it to cool it? 2 12" fans aren't near enough to cool it.

A good fan and a good fan shroud. You need a shroud that fits the whole surface of the radiator instead of just where the fan is. If you can fatten up your idle it will help it stay alittle cooler also.

[heshtesh]

You did'nt mention if it's boiling over,just built a 406 for a friend was doing the exact same thing heating that quickly. Turns out it was a bad sending unit.

[fbodyjunkie]

Will be picking up a infrered gun to check tomorrow. Tried to richen the idle circuit and retard the timing it slowed down but the temp was cool outside too. It just starts creeping. It hasn't boiled out but has blown out of the overflow once. Once it starts rising it never goes back down. I have tried turning the water pump off and the engine temp does not go up, but after sittng a few minutes at the same temp, lets say190, I can turn the pump on an dit will shoot up to 220 and then come back about 210. Will go up from there. I was thinking maybe I had the water pump wired wrong but it seems to flow right. I have even tried the same with the fans and it will do the same thing. Maybe it is the sender, would suck as it's a new autometer gauge but would be great to be that easy of a fix.

[cepx111]

Question, is it a electrical sender unit or mechanical?
The reason I'm asking the electrical sender may be reading wrong since you said it hasn't boiled over, 240 is pretty warm.
I had one that was off by almost 30 degrees (autometer), compared to a mechanical unit.

Running straight water will make it run quite a bit cooler, also using some of that water wetter stuff will help. Redline makes some $10 a bottle.

Using straight water and water wetter should drop it around 20 degrees and also do like dparker suggested - fully enclose the raditor with a fitted shroud.
You just might need a bigger radiator with that intercooler in front of it those things emit off alot of heat.


Goodluck and let us know what helps.
Cp

[wmeabates]

Like Dparker and CP said a shroud will help if you don't have one.2 12 in. fans are about 230 sq.in. a 17x27 rad core is about 460 sq.in.so your only pulling air over about 1/2 the rad.About retarding the timing that will put more heat in the cooling system most times,on the other hand removeing some mech.addvance and adding some initial timing will let it run cooler at low rpm an still have the total timing at high rpm.Bill.

[fbodyjunkie]

I tried the retard, thinking I maybe too far advanced but it's back to 28 total. The carb is as rich as I can get it and after some instructions from C&S got the idle to 1000 rpm's. The sender is mechanical and seems to be correct accord to the infrared gun I picked up. I'll try and go with a totally enclosed dual fan setup. I have 1 but it's pushers and I haven't got room for it. I have about 3" behind the radiator in most places and a few that is close to 2". If I can convert the pushers to pullers I would use this set up. Talking to a couple of racing friends that has been around the block, I'm told the CSR water pumps aren't good for any street driving as they don't flow enough water. I'm told a mechanical hi flow pump should cure the problem. The only problem with that, is I don't have the drive setup for the supercharger and will have get 1. This thing is driving me nuts and broke. I like the looks and the fit of everything with my current setup. I hope there's way to keep it and keep the car cool. Thanks for all the input guys.

[kwkracing]

Do not use pusher fans. They actually block air flow acting as a big shield in front of the radiator, air looks for the path of least resistance which would be around your radiator and not threw it. I went threw this samw prob with my blown sbc

[ksk454]

I'm a tad late to the party, but I took interest in this post. I have a very similiar setup.

I have a GenVI 502, running 9.75:1 compression. Meziere WP300U water pump (55gph model). I have a Northern Racing radiator that measures 31x19. Timing is 38 total, 1050 dominator carb, 89 jets, stock bleeds. dual 12" puller fans, no shroud. Nothing in front of the radiator at all.

I've pulled out the thermostat completely with no success. As long as the engine is running it continues to build heat with no stopping. Since it's drag only, I make a pass then shut it down to cool if off, which it will do alright. Where I run into problems is back to back runs when that happens. If I start at 190 for the first pass, by the time I get back to make my second run, I'm already over 220. I'm not comfortable running over that temp, so I end up scratching. I've got a head scratcher. Going to try bigger fans and shroud to see if that helps. If it doesn't, going to tear down motor to see if something internal is causing the problem.

Any suggestions are greatly appreciated.

[CamBirdRacing]

I have that problem every time I change engines out. I found out that the new engine (old block) rusts on the inside and after running it, the rust breals loose and plugs the radiator. I will get the radiator cleaned out and it fixes the problem.

[Jordan1984]

I had a over heating problem in my sbc before. Mine was due to a dead cylinder- I wiped the lobes off of the camshaft by not adjusting the valves right and the engine had to work harder, with more timing, to make power. I changed out the cam, added an electric water pump and it solved my problem. Just a shot in the dark, but it may run hotter than stock motor and bore due to the thinner cylinder walls from the .40 over bore.
JMO

[cepx111]

I had a over heating problem in my sbc before. Mine was due to a dead cylinder- I wiped the lobes off of the camshaft by not adjusting the valves right and the engine had to work harder, with more timing, to make power. I changed out the cam, added an electric water pump and it solved my problem. Just a shot in the dark, but it may run hotter than stock motor and bore due to the thinner cylinder walls from the .40 over bore.
JMO


FYI .040 is not thin for a big iron.

Jordan, didnt you notice a dead miss with that cam wiped out?? Or did you think it was just hittin hard.

You just bumped the timing up and poured the coal to it huh...lol
Too funny.

[StrokersGraphics]

this is somthing i have seen several times, you must restrict the flow at the thermostat housing. i just gut a thermostat put it in.

NOW!! my real question is what pound radiator cap are you running? you need at least 18lbs. i run 22-24 lbs on my radiator. what happens is if you don't run a large enough cap the rad fluid evaporates and/or lets the fluid pass the cap and fill your overflow catch can.

if this does not work you might want to take the heads off and see if you have a blown headgasket.