any thoughts, my bbc gets hot @ idle

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06-14-2009, 07:23 PM
hottrodd57

any thoughts, my bbc gets hot @ idle

have a 39 chevy coupe with a 1970 454 bbc, high flow aluminum short water pump, walker corba z radiator, a 16" 3,000 cfm electric fan(puller). headers are ceramic caoted inside @ out, when driving the car is runs 190 degrees or less, it starts slowly gettting hot when i am in alot stop & go traffic or @ car shows following crowds(takes 10-15min @ idle or 5mph less speed to get to 220), as soon as i can get up to 45mph or higher the temp drops down to normal within 3 min. I am guessing the problem is not enough air flow at slow speed, to get the hot air out. any ideas that will work to keep the engine cool a idle? I really don't want to do it, but I thought that wraping the headers would help cut down on the under hood heat, any thought on what i can do to fix the problem? would changing to a aluminum radiator help, I have always had good luck with walker radiators in my other cars? thanks guys
06-14-2009, 07:35 PM
Dave Severson

Does your fan have a shroud???
06-14-2009, 08:06 PM
pat mccarthy

it a bbc it happens do this try a stewert water pump .pick up the water speed try running a vacuum advance dist run a hi flow stat and use purple ice .last thing i would do is look at the radiator
06-14-2009, 08:10 PM
hottrodd57

the only shroud, is the built on one that is made on the elec. fan,I just barly can get the fan in due to the closness of the water pump & the rad. I will try to post a pic of the fan tomorrow, seem like any of the great OEM 2 stage electric fans(tarus & viper) are to big, anyone know of a super high amp & cfm 2 stage 16" fan?
06-14-2009, 08:15 PM
pat mccarthy

you need alot cfm with a bbc i would pick up your water speed i played this game try what i posted it has drop mine 20 in temp
06-14-2009, 08:19 PM
hottrodd57

at idle in gear it is 800rpms, I am using a wiends hi flow water pump, it the stewart pump better., already using purple ice add.
06-14-2009, 08:36 PM
pat mccarthy

Quote:

Originally Posted by hottrodd57

at idle in gear it is 800rpms, I am using a wiends hi flow water pump, it the stewart pump better., already using purple ice add.

well i see you have the hi flow wieand water pump i have one in one car and the stewart in the blower car .try picking up the water speed your car idles in gear 800 that not bad you could look at a black max fan i think that what it was when i put a 548 14to8 in a 28 ford or the spall fans a oem fan out of a grand prix may do the job what dist do you have ? be nice to see less then 220 but it not to bad if it will not go past that your ok
06-14-2009, 08:39 PM
hottrodd57

was just at the stewart website, if the stage 2 3, or 4 would really increase the water flow I would buy one, can you tell a big different in the flow vs the wiends?
06-14-2009, 08:47 PM
pat mccarthy

Quote:

Originally Posted by hottrodd57

was just at the stewart website, if the stage 2 3, or 4 would really increase the water flow I would buy one, can you tell a big different in the flow vs the wiends?

that is not so EZ one pump is in a 10.5 cr 632 donovan gto and the other is on a 50 chevy 548 blown so it hard to say but i would call them and try it i think i have the stage 2 .when all said in done it could be dead air
06-15-2009, 05:22 AM
R Pope

Either the hot air can't get out of the engine room, or it's recirculating under the bumper and getting pulled back through the rad. The first can be fixed by opening up louvers in the fender liners, or temporarily by removing the hood. A BBC is a fat engine, pretty much blocks the normal flow that was enough for an inliner.
If it's the second thing, test for it by just standing in front of the idling car and feeling for hot air blowing out the front end, under the bumper. Maybe some baffling will fix it.
06-15-2009, 05:35 AM
pat mccarthy

if dead air louvering inners may help if the air can not get out taking the hood off may not help it never help on my chevy
06-15-2009, 07:29 AM
jerry clayton

I don't believe you have said---but are you running underdrive pulleys???????????Seems a lot of the electric and cooling problems we see are underdrive pulleys
06-15-2009, 09:48 AM
hottrodd57

no using oem size pulleys, just in aluminum, no heat coming out under the front end, I have somewhat figured that the heat is trapped in the engine bay @ slow speed, and yes the bbc is fat, I had to have headers built to go over the frame rail & dump at the rear of the front fenders then go back under the frame, so I have probably blocked the air flow going around the engine, do you think installing small 7" electric fans in the inner fenders to pull the heat out? or would header wrap work?
06-15-2009, 04:53 PM
pat mccarthy

try a smaller pulley on the water pump .pick up water speed