What is the Question?

Did you have a question in particular? For aerodynamic reasons you want it as high as possible without compromising your cowl clearance.

Hans
 
Set up per SJ.

No questions in particular. Just looking for suggestions or comments to get it right.

I have the plenum as high as I could get it. Was trying to get it up so the top plug wires would workout! Didn't think about the airflow at that point.

Thanks
 
It Seems Very Low

When I look at this pic it looks very low:
RV-4%20Plenum%20046.jpg


When you say you put it as high as possible, what was your limiting factor?

I am concerned that you have it too low to cool that back cylinder. I would fly it first before making any changes at this stage, but it looks really low to me.

Hans
 
Too Low.

I'm going to the shop now.

I'm going to guage it compared to the prints from SJ.

Thanks for looking. I'll be back.
 
James Plenum on RV-4

Here is a picture of a Sam James Plenum on an RV-4 for reference
2nvt4si.jpg


Note the pad of silicone on the right side due to the occasional bump of the cowl.
t5ht3n.jpg


s41l5t.jpg
 
Too Low.

Hans, This picture is of my setup. However Andy has a better shot of the front of his plenum!
dof58sJh1jkBgaNkmsE61g


Looking at both sides of the rear of the plenum, at the #4 Cyl it sits lower. If you pull up on the plenum at the #4 cyl. it would make the plenum go down at the #2 Cyl. As I installed it I just made sure it missed the top cowling. After putting the cowl back on today to check, it could have been another 1/2" higher without hitting.

I think I'll take your advise and fly it before moving anything.

Thanks for looking.
Thanks for the pic. Andy.
 
Sorry to jump in on your thread but the title caught my attention.

Ryan Dean & I were at a fly-in in Winter Haven, FL yesterday when a man approached him about his RV4. Ryan stated that he especially liked another RV4 with the Sam James cowl that was just across from us.
The gentlemen said "I'm Sam James".
We had an interesting discussion on the features & functionality of his enhancements.
 
Just finishing mine

I have a lot more than 50 hours in my plenum installation, but I'd be happy to share the results. Take a look at some photos here:

http://picasaweb.google.com/lh/sredir?uname=106910711433382157244&target=ALBUM&id=5539603400121630305&authkey=Gv1sRgCNHyxbzd6NCC_wE&feat=email

Highlights:

1) I wanted my plenum to meet the following criteria: excellent seal all around, perfect alignment with cowl inlets, and no silicone goop sealing the plenum in place (so I can remove it easily). To achieve these objectives, I had to remold about 3/4 of the perimeter of the plenum. This included hacking off the inlet ports and relocating them to align with the cowl openings. The rest of the perimeter mods were to get a perfect fit with the modified Van's baffle kit.

2) If you use a 4" FP prop extension with the James cowl, clearance over the engine gets very limited, so it's critical to carefully fit the plenum, particularly at the rear edge over the cylinders. It took a while to find the best compromise between spark plug clearance, airflow, and cowl clearance.

3) After 3 revisions on the oil cooler mount, I decided not to attach it to the #4 baffle. Instead, it's secured to the engine mount, with a flexible supply duct made from Van's rubber baffle material material (See photos). I had trouble finding room for the oil cooler that allowed sufficient airflow and sufficient room for the oil lines.
 
Sam James

I've talked with him on the phone a couple times. I bet he's interesting in person.

I heard different opinions on the fit and function of the SJ products. I have to say the cowl was pretty simple to install, my first by the way!
 
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