Couple of radiator surround and radiator protection questions

[JohnK]

I'm buttoning up some details on the front end of the car before I get the body back from paint, and have a few questions:

1) I'm planning to install Mike Everson's (Replicaparts) radiator surround panel. Those of you that have installed one of these - did it require any trimming or did it fit well out of the box? I'm planning to powder coat mine but don't have the body on the chassis at the moment to test fit it.

2) Ideally, I'd like to PC the radiator surround and rivet it in place, and have it ready to go when the body is painted. This way the body can just be slipped on with the surround in place. Will this work, or does the radiator surround need to go on after the body is on the chassis?

3) I'm also debating various options for radiator protection. One option is the Nomex honeycomb material that several others have used. When mocking it up against the radiator, it stands proud of the radiator side tanks, but not by much. Do I need to trim the radiator surround to account for the extra thickness of the Nomex material, or is there enough "squish" in the bulb seal on the radiator surround to accomodate the thickness of the Nomex material?

FWIW - I will also be installing the Breeze upper radiator shroud, and have already installed the Breeze upper and lower radiator mounts and set the radiator to the recommended 58* for the Replicaparts surround.

Thanks,
John

[Ed Mc]

John

I used the radiator surround and the Nomex protection on my build. I also powder coated the surround black and painted the Nomex material and radiator tanks black to match so everything you see through the opening is black. The radiator surround did need to be trimmed, so I made a cardboard template then cut the surround after it was powder coated. I trimmed the Nomex to fit between the radiator tanks, added four clips at the top, also used the Breeze upper and lower mounts, to the top mount. The surround holds the bottom of the Nomex in place as well as the tanks on the side. Two years of driving and it has not moved. Easy to remove to clean as well

Ed

[JohnK]

Thanks Ed, I appreciate it. It sounds like I should hold off on powder coating and installing the radiator surround until after I get the body on the chassis for the final time.

-John

[Ed Mc]

You will not be able to determine the final figment until the body is on. The surround rolls up fairly easily so not a big deal sliding into place with the body on

[Fman]

John, Are you referring to the ME nose cone piece? If yes, that can definitely be installed after the body is on, I found if you loosen the lower breeze radiator cross mount it will slightly drop the radiator and open up some more space for the nose piece. Mine did not require any trimming. I removed my upper breeze radiator gap cover, I found it was preventing air flow from entering the engine compartment when driving. When I removed it my under hood temps dropped 20 degrees (monitored it on my EFI tablet).

This is how my nose piece ended up fitting...

https://thefactoryfiveforum.com/attachment.php?attachmentid=165419&d=1649822516

You can see where I had the Breeze radiator cover installed and how much airflow it was blocking when the car is moving...

https://thefactoryfiveforum.com/attachment.php?attachmentid=163915&d=1647266654

[JohnK]

Hey Travis. Yes, that's the piece I'm referring to. Thanks - that's very helpful!

[CraigS]

The radiator surround is a really nice piece. Mine was on my MkII so not sure how much would be different in a MkIV but I would fit it and coat after the body is back on.

[BEAR-AvHistory]

https://thefactoryfiveforum.com/attachment.php?attachmentid=105223&d=1554744288

Last piece was a Nomex honeycomb sprayed black to keep rocks off the radiator.

[Scott L]

I added some radiator protection, so I had to trim mine. This should definitely be fitted after the body goes on. Make a cardboard template from Mikes part, and trim for a perfect fit. The bulb seal hides any rough edges. Mine is a tight press fit, no screws or rivets required for me. Looks great!.

173600

[facultyofmusic]

John, Are you referring to the ME nose cone piece? If yes, that can definitely be installed after the body is on, I found if you loosen the lower breeze radiator cross mount it will slightly drop the radiator and open up some more space for the nose piece. Mine did not require any trimming. I removed my upper breeze radiator gap cover, I found it was preventing air flow from entering the engine compartment when driving. When I removed it my under hood temps dropped 20 degrees (monitored it on my EFI tablet).

This is how my nose piece ended up fitting...

https://thefactoryfiveforum.com/attachment.php?attachmentid=165419&d=1649822516

You can see where I had the Breeze radiator cover installed and how much airflow it was blocking when the car is moving...

https://thefactoryfiveforum.com/attachment.php?attachmentid=163915&d=1647266654

Hey Travis, I'm confused by the removal of the "gap cover". Are you referring to the radiator cowl? and if so, it's SUPPOSED to force more air to go through the radiator right?

[JohnK]

I think what Travis is saying is that with the Breeze upper shroud piece in place, all the air is being forced through the radiator (exactly as intended) but the consequence is that all the air flowing into the engine compartment is hot air that's come through the radiator first. It sounds like removing the Breeze upper shroud is allowing some fresh air to bypass the radiator and flow into the engine bay, thereby somewhat reducing under-hood temps.

[facultyofmusic]

Ahh, I think my missing piece here is not understanding why high under-hood temp is undesirable. Is it bad due to rising intake temps?

[JohnK]

I'm guessing there's a marginal impact on intake air density and therefore HP. Initially I think I'm going to opt to install the Breeze upper shroud as I'd rather prioritize maximizing airflow through the radiator over HP, but it's easy enough to remove down the road if necessary.

[Windsor]

Ahh, I think my missing piece here is not understanding why high under-hood temp is undesirable. Is it bad due to rising intake temps?

flexible and plastic bits age faster with higher temps. Some get mushy (e.g. rubber hoses) and some get brittle (wire sheathing, injector plug housings).

As an example, 1993 RX-7s had horrible under-hood temps and wiring harness couplers turned brittle in five-to-ten years when normally it takes more than 25.

You can mitigate some of it by using silicone for hoses and wire sheathing, but you can't do that everywhere.

[BEAR-AvHistory]

You can always pipe in cool air for the intake through the oil cooler opening. Advantage of 100% air flow through the radiator is a cooler running engine. Even without a shroud have never exceeded 205*F sitting in traffic during the NC summer.

[JohnK]

The stainless steel perforated screen (https://thefactoryfiveforum.com/showthread.php?31167-Greek-Guys-Garage-Roadster-Build-9509-(Radiator-protection-screen)&p=505567&viewfull=1#post505567) that I ultimately ended up choosing for the radiator protection has an open area of 64%, so I lose some airflow in exchange for radiator protection. Forcing 100% of the air coming into the snout through the radiator hopefully compensates to some extent for the restriction that the screen creates. The coyote runs pretty cool to begin with, so I'm not overly concerned about overheating, even with the radiator screen in place.

[Fman]

I'm guessing there's a marginal impact on intake air density and therefore HP. Initially I think I'm going to opt to install the Breeze upper shroud as I'd rather prioritize maximizing airflow through the radiator over HP, but it's easy enough to remove down the road if necessary.

I have noticed no engine temperature differences with the upper shroud removed. I don't drive much in the heat but on a low 90 degree day I still run at 185 all day long even in traffic. I would bet your Coyote will be totally fine without it but as you mentioned you can always remove it later on if desired. It definitely does look much better with the hood open and the Breeze upper shroud installed rather than the large gap.

[Fman]

Ahh, I think my missing piece here is not understanding why high under-hood temp is undesirable. Is it bad due to rising intake temps?

Cooler air is denser (more oxygen molecules for better combustion) than hot air and always make engines run better, especially a push rod engine. I feel like removing that upper shroud really did allow noticeably more airflow to enter the engine compartment when car is moving. A cooler engine compartment also leads to a cooler foot box.