DragStuff

hey guys, we have a bbc 454 street motor that wants to run around 210-220 degrees. trying to figure out how to lower the temps some. the car is a 64 chevelle with a freshly rebuilt 454, solid roller cam, aluminum heads and a dart intake with 4150 holley 750.
It has a new very large 4 flew radiator, 2 new electric fans 2000 cfm each, a new electric waterpump that is circulating very well.
We have tried it with and without a thermostat. We have tried running the timing from 37 degrees and is currently down to 32 degrees with no change to motor temp. If the car is left to idle for 10 minutes the temp will be around 210 degrees. It only goes up when the car is in motion.
The copper head gaskets can only go on 1 way and all water passages are clear. The water pump wiring is not reversed as per instructions.
Any ideas? We know the carb is on the small side but the plugs arnt indicating a lean mixture. The motor is still tight so maybe that could be some of it. dont know. any help appreciated. thanks, bucket

What gas? I don't run a thermostat but have a plate that fits into the water neck with around a 3/4 to 7/8 hole in it to slow down the flow a little. I used to have a 477 with the block filled so only the heads got water and it would get up to 210 after a 30 mile cruise. How hot does it get? Ever past 220?

71Hellride wrote:What gas? I don't run a thermostat but have a plate that fits into the water neck with around a 3/4 to 7/8 hole in it to slow down the flow a little. I used to have a 477 with the block filled so only the heads got water and it would get up to 210 after a 30 mile cruise. How hot does it get? Ever past 220?

its running on 87 octain. its a flat top motor with open chamber heads. this motor runs 210 after 10 minutes at idle and goes up to 220 going around the block. (approx. 2 miles). no block fill. we havent driven it any further due to temp. thanks

What kind of electric water pump do you have?

That's weird, I was going to suggest timing...My 402 struggles to make it to 180° at 36°, but makes it to 210° very quickly at 38°. How hot are the plugs? (im fishing here). You may play with your IFRs (Idle Feed Restrictors) in the carb you could make them a bit bigger. My carb guy sent me smaller ones when I was running 36° and struggling to get the motor to warm up. Before the IFR change it wouldn't make it above 160°. Now that I found my timing was a bit low, I'm going to try my original IFRs next time at the track. You may give Holley a call, it might just need a little more gas to quench its thirst at idle.

My .02

the water pump is a summit brand.
spoke with quickfuel today. they said the 750 should be fine. They said even on a carb that is too small it would be more likely to run rich at idle due to the vacuum of the motor pulling fuel from other circuits of the carb instead of idle fuel mixture alone.
we have ordered a milodon high flow thermastat and a new water temp guage to see if it will make a diff.
we are still plugging away at it inbetween other projects. thanks

Are you using the correct head gaskets ? Dumb question maybe, but I have heard (somewhere) that you can block water passage and steam holes by using the wrong head gaskets.

My 2c...

Don't know if this will matter or not, but I was informed that if I needed to run a thermostat, to buy one from EMP/ Stewart Components that has the three, 3/16" bypass holes in it.

Is there any chance you got some trapped air in the system?

Bruce

Are fans really blowing? Do they blow enough that it is almost painful to be hind them.
If not.... There is a lot of different between good fans and fans with big numbers.

CDR Performance wrote:Are fans really blowing? Do they blow enough that it is almost painful to be hind them.
If not.... There is a lot of different between good fans and fans with big numbers.

Concur. I bought a big honking Fluidyne radiator and discovered that a Flex-a-lite Black Magic fan could not get air through it. I ended up with a large 6 blade steel fan on the front of the water pump with a pretty tight shroud.

were is the temp sending unit located?
intake or head?
air in the system still!
the temp really isnt that high for a street bbc
how is all this wired?
fans, pump

both fans and waterpump are wired through a relay to +12v.
the temp guage is plumbed into one of the water holes on front of the intake.
the head gaskets are copper gaskets.
If you big block guys were driving down the street and your temp was around 210-215, would you be alarmed or would that be on the high side or normal? my wifes pontiac always runs 210 but has a high temp thermostat for increased fuel milage.

its right their

is the timing locked
what does the plugs look like after you let it set and idle

I tried an electric water pump on a street driven 454 and it would not move enough water to keep it cool ! Put the belt driven moroso alum pump back on an it runs 180 all day ! That is prob why temp is OK when u let it idle for 10 min !

Over a decade ago I street drove a Alum headed, 540 cid, 13-1, 0.7xxx" + cam, with 36 of timing. (9's @148 motor)
C&R, CSI Water pump,and Spal single fan. Tried griffin radiators they got too many holes from road debris.
Maybe 190 sitting in traffic (on grill opening) 170 rolling. No Stat and a 3/4 shim.