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Discussion Starter #21
Is the Vintage Front Runner Kit a single belt? If it is would that not require a "reverse" turn water pump? I would make sure you have the right type pump before changing radiators and such.
It is the single belt with idler. Vintage Airs website just says it is a Stewart Hi-Perf Aluminum Water Pump. It would be Tuesday before I could call them but it is the pump that came with the kit. I cannot find anything on their website that refers to a reverse flow water pump. The replacement part number for the big block is Part #: 72231-BCP on vintage airs website. That is for the short pump. Not sure if his cars got a short or long pump.
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What is the engine rpm @ 55 mph? Make sure you check the timing at that engine speed. I recommend manifold vacuum at the distributor vacuum advance.
 

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I agree Pmotion's statement to "hook the VA can to full manifold vacuum"... but you need to also know how much advance the VA can is providing. Most aftermarket adjustable VA cans can produce 20+ degrees of crank advance at full pull. If you set your initial mechanical timing to 15°, you could have 35° (or more) initial timing once you connect the VA can to a full time vacuum source. And while cruising, your 34° of mechanical timing could be at 54° total timing... or higher.

The best way to control how much advance the VA can is providing at full pull is to add a VA limiter/stop plate to limit the VA can to about 10°- 12° of advance at the crank. Since your friend already has an HEI distributor, this is easy to resolve. Just install an MSD 84281 Limiter Plate.
Below is a photo of the MSD VA limiter plate - Red Arrow (part #84281) that I installed on my HEI to limit the VA to add 11° of advance at full pull.
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Discussion Starter #25
Looks like the plumbing is wrong according to the pictures I see. Look at the last picture in this article. It shows a bypass hose from the intake to the water pump. The picture of the Chevelle shows a temperature sensor(or sender). Could be a factor.

Outlets are limited and we needed the bypass outlet for one of the temp gauges. From what we have read there are ways around running the bypass like drilling the thermostat. He is running the Stewarts thermostat with the holes drilled. Not saying that this isn't the problem and to be honest It is something to try just to see if it will work. Should be as easy as jerking the thermostat out and seeing if it will run hot. Some good reading on the bypass here.
 

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Discussion Starter #26
What is the engine rpm @ 55 mph? Make sure you check the timing at that engine speed. I recommend manifold vacuum at the distributor vacuum advance.
I would have to get in the car to see exactly what the engine RPM is at 55 mph but it has about a 3.08 gear so the rpms wouldn't be much over 2000 if that. I've checked the timing several times in the shop to check how much advance it has initially and total,when the curve starts and when it reaches total timing. I don't want to come across as a know it all and I do need and did ask for opinions but after having a timing light on it eight or ten times I'm having a hard time believing it's a timing issue. With that being said, honestly I don't have clue what the issue is. I've been working on and building engines for literally 40 years and this one has me scratching my head. There is one thing though. I have no doubt that eventually this car will cool going down the road just like it is supposed to. I'm just hoping at this point that it isn't something crazy like somebody pushing the freeze plugs into the engine causing coolant flow problems inside the engine. I guess we've all seen goofy things cause problems.
 

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g2072 . . . . . . . about the water pump . . . . . I (thought) - that - I had read somewhere that your
'water pump drive belt' . . . . if it goes "over the w/p pulley . . . = standard rotation" . . . .
if the drive belt goes "under the w/p pulley . . . = reverse flow pump " .
Hey - I don't know - just adding the question . . . one more too check - off your list .
Then, is there any "numbers on that w/p" - for cross checking (that the correct w/p was shipped) ?
. . . or check any paper work ?
and, adding that w/p 'by-pass hose to intake' should be easy enough . . . . . (might entail removing
some parts to get installed ) , but , in the end game - - may be worth it .

just ideas . . . . your call . . . .

. . . jim
 

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Discussion Starter #28
The guy who owns the car is leaving town for a week or so. They were going to the Shades of the Past show in Pigeon Forge but once it was cancelled they decided to still go just without the cars. He doesn't have the paperwork for any of the parts. He bought the car running and the front runner system was already on it. I haven't been able to find anything about a reverse big block set up from vintage air but Stewarts does show a reverse rotation Wp for a big block. Probably going to replace water pump when replacing the radiator if for no other reason just to make sure the Wp isn't causing a problem. The car had been sitting up before he bought it (may have found out why) and while flushing the radiator there has been a lot of debris. I appreciate the ideas guys A lot of times a different perspective really helps. I know I get to thinking a certain way and when one of the minds are mine two or three minds are a lot better than one.
 

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My car heats up to about 210-215 at highway speeds but never comes back down. Even at idle. I’ve put a new water pump, had the radiator flushed, checked timing, everything I can think of and no help. I feel your pain.
 

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I have a friend with a 1967 Chevelle that has a mild 396 big block in it. It has a champion aluminum radiator in it with two electric fans on it. I have checked to make sure the fans are turning the right way. While the car is going down the road it is wanting to heat up. He usually stops it when it gets in the 215 area. If he stops the car and lets it idle it will cool back down. It has a Vintage air front runner system on it with I'm sure a stewart water pump. The water pump seems to be circulating the water in the radiator fine. I would think the car should be getting plenty enough air going down the road to cool it. It has two gauges on it. A Dakota Digital and a Sniper coolant temp sensor. Both gauges are reading pretty close so I don't think it a gauge issue. My friend has tried several thermostats and flushed the radiator out using several different brands of radiator flush. I've been around cars all my life and what I'm seeing simply doesn't make sense. Most of the time if a car is heating up going down the road it is a air flow issue. On my 1965 Nova I can take the relay's out of my fans and it won't heat up driving at highway speeds. I've actually seen him drive up with the car running close to 220 and let it idle in my driveway until it cools enough to start cycling the fans off and on. At this point I'm thinking it must be a radiator or water pump issue but just looking at them they seem to be fine. It isn't losing water to make me think it's a engine problem and I set the timing myself so I know it's right. Anybody want to venture a guess. Mike Goble?
I just bought two inner springs from InlineTube for only $5.25 each!
#11716 - about 1.5” x 12”
 

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I had read about several persons having a similar issue with cars in autocross and road course events. The cars would cool while sitting. But underway, the air would not exit the engine compartment and basically caused a traffic jam at the radiator. Putting vents in the hood let the air escape, allowing proper circulation through the radiator and cooling. I think ride height had something to do with it also. Does the engine compartment have somewhere for air to go.
 

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"....Does the engine compartment have somewhere for air to go. " That is my thought also. How does it look at the bottom and back of the engine compartment. If they have smoothed it all in with sheetmetal, there may not be enough exhausting of the air from the engine compartment.
 

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Discussion Starter #35
I had read about several persons having a similar issue with cars in autocross and road course events. The cars would cool while sitting. But underway, the air would not exit the engine compartment and basically caused a traffic jam at the radiator. Putting vents in the hood let the air escape, allowing proper circulation through the radiator and cooling. I think ride height had something to do with it also. Does the engine compartment have somewhere for air to go.
The car is fairly low. I really hope this isn't the problem because he doesn't want a cowl hood. We like the flat hood look. Once again it would be easy to make sure this wasn't the problem. Just jerk the hood off and take it for a spin. If there is a difference in cooling we could be on to something. It has factory inner fenders but nothing extra added but the firewall is filled and slick.

I don't see a radiator shroud, a pretty important piece for proper cooling!
It does have a fairly nice shroud with dual fans. It just isn't visible in the picture. We control the fans with a Dakota Digital pac 2750. It has dakota digital gauges in it. That's one of the reasons we aren't running the bypass. It has two sending units and the intake only has room for one since it has heater and AC. So far we haven't found anywhere to install a temp sender in the head or block. that would allow us to put the bypass hose on from water pump to intake. I don't like to run a temp sender out of the water neck unless it's the only place I got. If push comes to shove I can drill and tap another temperature sender hole beside the bypass outlet.
 

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I have a friend with a 1967 Chevelle that has a mild 396 big block in it. It has a champion aluminum radiator in it with two electric fans on it. I have checked to make sure the fans are turning the right way. While the car is going down the road it is wanting to heat up. He usually stops it when it gets in the 215 area. If he stops the car and lets it idle it will cool back down. It has a Vintage air front runner system on it with I'm sure a stewart water pump. The water pump seems to be circulating the water in the radiator fine. I would think the car should be getting plenty enough air going down the road to cool it. It has two gauges on it. A Dakota Digital and a Sniper coolant temp sensor. Both gauges are reading pretty close so I don't think it a gauge issue. My friend has tried several thermostats and flushed the radiator out using several different brands of radiator flush. I've been around cars all my life and what I'm seeing simply doesn't make sense. Most of the time if a car is heating up going down the road it is a air flow issue. On my 1965 Nova I can take the relay's out of my fans and it won't heat up driving at highway speeds. I've actually seen him drive up with the car running close to 220 and let it idle in my driveway until it cools enough to start cycling the fans off and on. At this point I'm thinking it must be a radiator or water pump issue but just looking at them they seem to be fine. It isn't losing water to make me think it's a engine problem and I set the timing myself so I know it's right. Anybody want to venture a guess. Mike Goble?
You should read the Road and Track issue About 1968 Corvette 427, they all ran 230, btw 220 is not really considered hot, I personally would drive that car anywhere. Have a thermostat that like 180 and your cooling system is not capable of keeping it at 180 so the thermostat would stay open all the time after warm up would and let the water go thru the radiator too fast wouldn’t work as well as say a 190 thermostat and if it’s a fresh build on the engine a good 100 mile trip at 60 to 70 mph Will do wanders for it
 

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Have a thermostat that like 180 and your cooling system is not capable of keeping it at 180 so the thermostat would stay open all the time after warm up would and let the water go thru the radiator too fast
The truth is, the faster the water goes through the radiator ( up to the point of damaging the radiator ) the more heat it dissipates. It's physics - the greater the Δt, the greater the heat transfer.
 

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You want fast movement of water through the radiator but want a thermostat to regulate the temperature. If it's slow than the engine is heating up the coolant even more while the coolant in the rad cools down but not enough to lower the overall temperature. EDIT: Mike beat me on that one. He's the smart one on cooling systems.
 

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All really good points . . . . (y)

jim
 
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