hard filled sbc overheats real bad

Old 09-05-2012, 05:38 PM
  #31  
chevyart
Senior Member
MASTER BUILDER
Thread Starter
 
Join Date: Mar 2008
Posts: 173
Default overhesting

thanks zip. i will try that method tomorrow. its a summit electric water pump and it worked fine along with all the other cooling parts when i had the 355 smalll block in there and it was not filled.. thats what is throwing me off so much. the other engine ran at about 195 on the hotest day. my radiator is the next thing to check. its a 69 camaro big block radiator and the fan is an electric one with a plastic shroud. i dont know the cfms, but this setup seems to cool down the engine after a run pretty quickly, but it also get real hot again before i get back to my spot in the pits(240). thanks art
chevyart is offline  
Old 09-05-2012, 06:39 PM
  #32  
roadkill2
Senior Member
RACING JUNKIE
 
Join Date: Jan 2012
Posts: 628
Default Re: overheat

Originally Posted by chevyart
PS biggest thing i dont understand is the car shoots up to 240 during pass and as soon as i let off the gas it goes back pretty quickly to the 200-210 range. cools down to 180 in 5 minutes(i stop and run waterpump and fan) and is back up to 240-250 by the time i arrive in the pits. does this sound like a radiator problem or waterpump problem thanks art
You're apparently really lean. Fatten the damned thing up until it blubbers and drive it the same distance you have to go on the return road . . if the temp stays down, there's your problem . . If it doesn't (again) Check the temp of the bottom radiator hose. If it's over 145 the water's going through the radiator too fast . .

The 496 we were running was full of hardblok to within about an inch of the deck. The back water transfer holes don't exist on a Dart manifold. As I said before, there was no heating issue at all . . and while we tow the car back, it isn't about engine heat, never had a problem when we drove it back, but we tow to keep the converter temp down and it's a lot easier to cool off (the converter) if it gets back to the trailer at about 180 or a little less . . And as I said above, generally, when the car gets back, the Thermostat housing is about 100 . . Can't ask for anything better than that . . And the 582 behaves almost exactly the same way although it's got a unfilled water jacket . .
roadkill2 is offline  
Old 09-05-2012, 09:33 PM
  #33  
trmnatr
Junior Member
SHOW GUEST
 
Join Date: Dec 2007
Posts: 4
Default Re: overheat

Originally Posted by chevyart
thanks trmnatr and roadkill 2. this problem is making me sick and i dont want to hurt my new engine. wazup has really been helpful along the way with his explanations and i am concerned with the whole hard blocked thing. you explained that the water does not move at all below the bottom of the water pump holes. above that line does the water circulate around the sides of the block, or is there no water movement in sides of the block. at all? my engine has holes drilled and tapped to accept a #6an fitting on each side in aprox center of engine , right above the hard block material. (its a 400 block). i guess the holes were drilled either to drain water or possibly circulate water to this area by tapping the sides of the waterpump and pumping cool water over to the area above the hard block all along the sides of the block.. my manifold does not have bungs in the rear to send lines from front to rear of intake, and there are no tapped holes in the heads to accept lines from either waterpump or lines from thermostat housing area i am.thinking strongly about running the lines from waterpump to holes tapped in block as i explained above. is this a waste of time? also, how do i know if my waterpump is performing.. PS biggest thing i dont understand is the car shoots up to 240 during pass and as soon as i let off the gas it goes back pretty quickly to the 200-210 range. cools down to 180 in 5 minutes(i stop and run waterpump and fan) and is back up to 240-250 by the time i arrive in the pits. does this sound like a radiator problem or waterpump problem thanks art
What is your radiator caps pressure rating and is it holding pressure? (You can check it with a Stant radiator pump)
trmnatr is offline  
Old 09-06-2012, 04:57 AM
  #34  
chevyart
Senior Member
MASTER BUILDER
Thread Starter
 
Join Date: Mar 2008
Posts: 173
Default overheating

thanks trmantr. i only had a 7 lb cap on there first time out and i was told to get a higher pessure cap, which i did. its a brand new 16 lb pressure cap and it has the pressure relief valve on it. do you think this cap has enough pressure for my setup. PS no one has commented on my idea to run the 2 hoses from water pump to the sides of my engine block, just above the hard block material. wont this help cooling and circulation? thanks again art
chevyart is offline  
Old 09-06-2012, 05:15 AM
  #35  
wrightway
Senior Member
SENIOR BUILDER
 
Join Date: Feb 2005
Location: LAWTON MI
Posts: 113
Default

Originally Posted by zipper06
fill the radiator up, then pull the top hose off at the radiator, then put a bucket under the hose anf turn the pump on. it will pump until the water gets below the water pump. This should tell you if the water is moving pretty good or the pump is weak.

JMO

Zip.
X2
wrightway is offline  
Old 09-06-2012, 05:36 AM
  #36  
wrightway
Senior Member
SENIOR BUILDER
 
Join Date: Feb 2005
Location: LAWTON MI
Posts: 113
Default Re: overheating

Originally Posted by chevyart
car wont idle down low and when i put it low it shoots up and down.i have to idle it around 2000 to(maybe a tad lower) to drive it around pits and it definitely bumps hard into gear(powerglide)i never addresed that problem and i should have, right away. how does that make an engine overhear or make it have other bad affects? im putting a newer(bigger carb on. and i will look at the plugs from last sunday.. i iknow they werent quite brown enough last week, but i didnt want to go crazy with the jets. this carb has a new center section from proform. i had it on my old motor,(that blew up) and the car ran good with it, but i was more sure of the old carb for startup of newer motor. i will change the carb gasket
Can you borrow a well sorted out carb from someone?
Maybe it just me but i would never run a carb down the track that i can't get to idle correctly.
wrightway is offline  
Old 09-06-2012, 08:24 AM
  #37  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

You're right i never noticed about the high idle, i've never had an engine that wouldn't idle a 1,000 RPM's or less, my 377 idles at 800 or less, the 482 i was tuning a few weeks ago with atacks injection idles at 800 RPM's and that with a .743 lift cam.
:?: have you syncronized the butterflys on this carb that you are running, if you don't have a vacuum leak then it could very well be that you have some butterflys not closing all the way. It happens a lot if you're running a tunnel ram and 2 4 barrels, but i realine you're running a single 4 barrel.
Even my 1471 with buzzard catcher 360" blown alcohol sm/blk idles about a 1,000 RPM's with a lope down too 500 RPM's, but that's the way i tune it. It gets attention like the old funny cars when it lopes up to the starting line like a frog moving forward. I got a vid somewhere if i can find it.

Zip.

I found it. Sound UP

Here's motor right after adjusting the valves, there is some oil on the right header. i'm behind the camera.

http://video.google.com/videoplay?do...3485455&hl=en#
zipper06 is offline  
Old 09-06-2012, 09:31 AM
  #38  
wazup
Senior Member
EXPERT BUILDER
 
Join Date: Dec 2010
Posts: 345
Default

Zip just got to love them blowers. What kinda car is that a vega.

I have been waiting on some of you guys to jump in and try and help Art, just to many things with out being there to look at it.
wazup is offline  
Old 09-06-2012, 09:52 AM
  #39  
wrightway
Senior Member
SENIOR BUILDER
 
Join Date: Feb 2005
Location: LAWTON MI
Posts: 113
Default

Art does the car get faster as the day gets hotter? That's a sure sing of being lean.
Also are you sure the correct base plate gaskit was used when you installed the proform center? Have heard that problem more than once.
wrightway is offline  
Old 09-06-2012, 10:19 AM
  #40  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Originally Posted by wazup
Zip just got to love them blowers. What kinda car is that a vega.

I have been waiting on some of you guys to jump in and try and help Art, just to many things with out being there to look at it.
No Robert, it's in my friends very ugly 1963 Dodge Dart. When i built the engine i already had my 377" in my Malibu, so i just want to try the motor out and he had his motor out so that's how that happened. It ran pretty good until i cracked a cylinder and the block was filled all the way to the deck, but then i was running 30% OD and pushing 40 PSI of boost with a good Littlefield blower. I still have the whole setup but need a good Dart blk to put it back together as a 383 with alum rods.

Zip.
zipper06 is offline  

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service