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PostPosted: Wed Oct 07, 2026 4:39 pm 
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EFI Slant 6

Joined: Thu Apr 18, 2019 7:57 am
Posts: 481
Location: Lawrenceville, GA
Car Model: 1966 Dodge Dart
Trying to get more fan clearance in my '66 Dart. Currently using a 16" electric Flexalite fan and it struggles to keep temperature under control in stop and go traffic in Atlanta summers. I have found a very thin (2.5") Mercedes clutch fan that appears to clear the radiator but doesn't leave a lot of room. I am running polyurethane motor mounts, but would like to give the fan a bit more space for peace of mind. Are there any good ways to get the engine back about 1/2" to 1" or so in early A's?

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1966 Dodge Dart turbo / EFI project


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PostPosted: Wed Oct 07, 2026 8:41 pm 
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The quick answer is no. The full answer is not without spending a lotttttt more effort-money-time than it's worth. There are much less invasive/brutal ways of achieving what you want. Which one(s) to do depends on the current configuration, specification, and condition of your entire cooling system – radiator, fan shroud, hood-to-rad-support seal, thermostat, coolant type – and answers to questions like "What exactly does 'struggle to keep temperature under control' look like, and how is it being measured?" and "Does this car have air conditioning?".

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PostPosted: Thu Oct 08, 2026 4:34 am 
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Joined: Mon Oct 21, 2002 11:08 am
Posts: 17640
Location: Blacksburg, VA
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Yep, sounds like you have other cooling issues if a 16" will not do it. I have fit elec fans (1-2 depending on size, puller mode) in 64-66 A bodies with 2" deep custom-mounted deep alum radiators without much ado. Maybe radiator mounting needs to be modified?

I think you could move the engine and trans back 0.5" fairly easily. In fact, I should really do this when I put the engine back in my 64 Dart and when I put the 5spd in the 62.

I moved my 68 Dart's engine forward 5/8" by slotting the motor mount brackets on the engine (both engine side and mount side) and welding washers on for strength. Trans X-member will be more work, but should be too bad if you can weld. I did this when I put the A500 trans and 1.1" adapter plate in the 68.

Lou

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PostPosted: Thu Oct 08, 2026 1:12 pm 
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Joined: Wed Oct 23, 2002 7:57 pm
Posts: 9499
Location: Waynesboro, Pa.
Car Model: 65 Valiant 2Dr Post
I put a crossflow aluminum radiator in my Valiant and an electric fan in front of the radiator. It keeps it cool even in 98 degree temps at Bristol and North Wilkesboro. Fan rarely runs at all if the car is moving and this is a high compression race engine. Moving the fan to the front gives you a couple extra inches between the radiator and the water pump.

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PostPosted: Thu Oct 08, 2026 3:55 pm 
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EFI Slant 6

Joined: Thu Apr 18, 2019 7:57 am
Posts: 481
Location: Lawrenceville, GA
Car Model: 1966 Dodge Dart
Quote:
The quick answer is no. The full answer is not without spending a lotttttt more effort-money-time than it's worth. There are much less invasive/brutal ways of achieving what you want. Which one(s) to do depends on the current configuration, specification, and condition of your entire cooling system – radiator, fan shroud, hood-to-rad-support seal, thermostat, coolant type – and answers to questions like "What exactly does 'struggle to keep temperature under control' look like, and how is it being measured?" and "Does this car have air conditioning?".
To answer the questions:

1. Temperature is being measured through my EFI system. I have not tried to do a sensor-specific calibration, but my experience is it's usually accurate to within ~3 degrees.
2. It struggles with keeping cool sitting still except in cold weather. Temperature can creep up to 215-220 and I have not tried sitting still idle for longer to see exactly where it tops out. The temperature will start dropping once it starts moving, which is why I have been thinking more air volume.
3. No air conditioning. There is a large intercooler that precludes using a pusher fan.

Now for the specs.

Radiator: Currently a Suzuki Grand Vitara radiator, about a 17" x 21" aluminum core. Also had issues with a thick circle track radiator that didn't have as much fan room. At the time I bought the current radiator, Champion was out of stock on direct fit radiators, and I was trying to avoid a $800+ part from US Radiator.

Fan: Flex-A-Lite 16" electric. The previous setup had a 12" fan due to clearance issues.

Shroud: None.

Hood to radiator seal: Yes.

Thermostat: 180 degrees, holds this in cold weather.

Coolant type: 50/50 traditional green stuff.

One other thought is I might try to bring down the idle. I am currently running EFI without an IAC valve and set the idle as a compromise for cold starts. This means it's idling around 800-900 RPM with the transmission in drive at operating temperature.

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1966 Dodge Dart turbo / EFI project


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PostPosted: Thu Oct 08, 2026 4:49 pm 
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Quote:
Temperature can creep up to 215-220
This does not mean the car is overheating. If you are thinking along the lines of "I have a 180° thermostat, so the temperature should stay around that figure, and if it goes more than a little higher, that's an overheat"…that's not correct. The thermostat sets the minimum operating temperature, not the maximum.
Quote:
Shroud: None
This puts a limit on how much of the radiator core the fan can force air past.
Quote:
it's idling around 800-900 RPM with the transmission in drive at operating temperature.
That would be unpleasant to live with, and if you're spending a lot of time with your foot on the brake and the transmission in gear, it's gradually going to heat up your transmission fluid more than is nice.

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PostPosted: Fri Oct 09, 2026 4:49 am 
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Joined: Mon Oct 21, 2002 11:08 am
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Location: Blacksburg, VA
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Ahhh, intercooler. That is your space issue, I guess, and maybe limits airflow to rad. You could go to AEM water/MeOH injection and ditch the intercooler?

215-220 at idle may be just fine if it will hold that.

I have used Afco and Griffin and BeCool alum radiators with 2" core depth. What about 2X12" low profile puller fans?

Lou

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PostPosted: Sat Oct 10, 2026 5:16 am 
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EFI Slant 6

Joined: Thu Apr 18, 2019 7:57 am
Posts: 481
Location: Lawrenceville, GA
Car Model: 1966 Dodge Dart
This is one of those cases where I know that the temperatures I'm seeing are not dangerous, but the fact that I don't know where it tops out (and have been a bit too chicken to let it keep going up to see where or if it stops) has me somewhat worried. Atlanta has plenty of both traffic and hot days, and I would rather have the temperature stop at 215 and know it won't go any further.

I'm not sure of a good way to do a shroud for an electric fan without setting the fan back. I wonder if the Polybushings motor mounts may have somehow moved the engine a half inch forward or so?

At this point I am wondering if I should experiment with the clutch fan, or install an IAC valve so I don't have to set the throttle as a compromise between cold starts and hot idle.

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1966 Dodge Dart turbo / EFI project


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PostPosted: Sat Oct 10, 2026 11:48 am 
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By all means, install an IAC! I have some new self-contained Bosch ones (hose inlet/hose outlet) if you want easy-peasy-lemon-squeezy (send me a DM)

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Too many people who were born on third base actually believe they've hit a triple.

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PostPosted: Sat Oct 10, 2026 12:01 pm 
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EFI Slant 6

Joined: Thu Apr 18, 2019 7:57 am
Posts: 481
Location: Lawrenceville, GA
Car Model: 1966 Dodge Dart
Thanks, I think I have one lying around somewhere.

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Matt Cramer
1966 Dodge Dart turbo / EFI project


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PostPosted: Sat Oct 10, 2026 1:18 pm 
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Joined: Wed Oct 23, 2002 7:57 pm
Posts: 9499
Location: Waynesboro, Pa.
Car Model: 65 Valiant 2Dr Post
Your transmission mount should be holding the engine pretty close the proper location.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!
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12.70 @ 104.6
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