BUILD THREAD 78 Malibu 350 rocket build kind of
- Thread starter jasonhudsonCIA
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I figured out what it was. I had to go from a .100 jet to a .107 with 70x47 rods to compensate for the spacer and then it was just a little bit over advanced on the timing.
I don't have timing marks anymore so I had to go by ear which sucks but it worked.
I don't have timing marks anymore so I had to go by ear which sucks but it worked.
I'm having a bit of a problem with overheating. I noticed that it slowly overheats not quickly but a "slow burn" and it will maintain the temp heated up to when cruising. My electric fans are working so that's not it. I was thinking it's the way I have the heater hoses routed from the water pump.
Theres 2 ports on the water pump one is a bypass and the other is a heater port I think. I have the 3/4 hose hooked into the water pump and I noticed it was heating up instead of the one coming from the intake. I thought I was supposed to be vice versa but I'm not sure. Im sure it don't help trying to run the heater core backwards.
So any thermodynamics wizards out there have any clue cause I'm kind of stumped. I'm going to try and hook into the radiator port.
Theres 2 ports on the water pump one is a bypass and the other is a heater port I think. I have the 3/4 hose hooked into the water pump and I noticed it was heating up instead of the one coming from the intake. I thought I was supposed to be vice versa but I'm not sure. Im sure it don't help trying to run the heater core backwards.
So any thermodynamics wizards out there have any clue cause I'm kind of stumped. I'm going to try and hook into the radiator port.
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Well decided to change out the radiator for the s10 one I had lying around. No change really it still overheats very slowly. I'm sure it's something simple I'm missing. I don't think the motor is clogged.
Oh yeah I forgot to mention that it will hover around 210 unless I give it some gas or I'm going up a hill.
Oh yeah I forgot to mention that it will hover around 210 unless I give it some gas or I'm going up a hill.
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I believe the 3/4" hose goes to the pump. Mine does. As for overheating, I forget the details of your cooling system: radiator size & type, thermostat temp, fan CFM...
Before doing anything else it might be worth triple checking the airflow through the grille and such. Any blockages or alternate paths for the air would reduce the cooling ability. Have you performed a flush of the system to guarantee there's no corrosion buildup in the coolant passages?
Before doing anything else it might be worth triple checking the airflow through the grille and such. Any blockages or alternate paths for the air would reduce the cooling ability. Have you performed a flush of the system to guarantee there's no corrosion buildup in the coolant passages?
Ok let's see here. I had a 3 row rad aluminum I changed for an 2000 blazer radiator probably inadequate. 180 thermostat it's a motorad I think. The fans are a aftermarket kind 2 800 cfm probably inadequate on those too. I read on summit anything over 302 CI needs 2800 plus. And then the water pump is just a 5 blade impeller nothing fancy just had the extra heater port or whatever.
There is brown in the water now.
As for air flow I'm unsure I noticed the air dam in the front has a split.
Do these g bodies draw air off the road like a Camaro?
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I can't comment on the radiator, the fans are surely part of the issue, and the thermostat actually needs to be higher temp- but the t-stat isn't the issue.
Brown in the water: you running coolant as well or just straight water? Could just be rust, could be part of whatever is potentially causing the problem.
A cracked air dam won't perform perfectly but also wouldn't cause a temp spike like that. Running without an air dam can raise temps roughly 15-20°. In front of the radiator there's supposed to be some flaps that direct air to the radiator instead of letting it blow sideways, they can make about another 20° difference.
Draw air off the road in what manner? Gs don't really scoop it up from the hot pavement if that's the question.
Brown in the water: you running coolant as well or just straight water? Could just be rust, could be part of whatever is potentially causing the problem.
A cracked air dam won't perform perfectly but also wouldn't cause a temp spike like that. Running without an air dam can raise temps roughly 15-20°. In front of the radiator there's supposed to be some flaps that direct air to the radiator instead of letting it blow sideways, they can make about another 20° difference.
Draw air off the road in what manner? Gs don't really scoop it up from the hot pavement if that's the question.
I had issues with my 88 Cutlass running hot with Olds V. I tried multiple aluminum rads, fans, water pumps and thermostats. The GN rad rubber surround made the most difference. As said, the T stat won't make a difference, especially being a 180. The open impeller water pump is a minimal gain going to a closed impeller. That aluminum plastic Blazer radiator should be big enough to cool. Try something like a Dodge Stratus/Plymouth Breeze or Dodge Intrepid fan with a 40 amp relay. I had the Breeze fans on my 88 and now my 70, they really cool down quickly.
When I drove it home today it actually stayed around 180 or 185 just cruising. It didn't creep up to like 190 or 200 till I got to about 20 feet outside my house.
Yeah brown water. I am running coolant I think there's some rust from that cast iron intake or something I can't really remember.
And as for the air dam. I was asking if the air flow was directed from underneath the car like a Camaro. When I had that f body it didn't have an air dam and would run like 210 without it. but I know about the little flaps on the side of the core support that f body had em.
What should the thermostat be like like a 195?
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I couldn't find the gn fan shroud.
What about a Lincoln continental mark 6 or 7 fan? Ive heard of people using those. Not so sure on the cfm. but hey it's gotta be pretty good if it's trying to lift off the ground when testing them. I'll use intrepid fans if they're just as good.
Did they make a closed style water pump like a SBC? I imagine it's less leakage and more of a direct path.
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