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  #41  
Old 02-29-2016, 04:17 PM
bluebrear bluebrear is offline
 
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Jim,
How much did the temps drop, if I may ask? Just to know if I should cut the dams back. By the way, I saw a picture of a builder who had foamed the open sides of the upper cowl dams. Once smoothed, it seems like it would reduce some turbulence there.
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  #42  
Old 02-29-2016, 04:35 PM
vic syracuse vic syracuse is offline
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Quote:
Originally Posted by Jesse View Post
That's scary. That's an NPT thread port. Most CHT probes are strait threads, aren't they?
Yep! Was amazing to me! Been flying that way for over 120 hours, and even had a prebuy done (by someone else).

Vic
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  #43  
Old 03-01-2016, 06:46 AM
PaulR PaulR is offline
 
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Originally Posted by Jimzim View Post
Yep, I just used my Dremel to cut the ramp out, smoothed things up a bit, shortened it about an inch and a half as I recal, then glassed it back in. They say you should be able to make a fist and shove in through between the ramp and the cylinder. I'm there now. It was easy.
Jim
Jim,
How much did this lower your CHT's if I might ask. I'm about to do this myself but pondering the benefit.
Thanks
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  #44  
Old 03-01-2016, 12:42 PM
alpinelakespilot2000 alpinelakespilot2000 is offline
 
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Originally Posted by PaulR View Post
Jim,
How much did this lower your CHT's if I might ask. I'm about to do this myself but pondering the benefit.
Thanks
I too am interested. I can get a full fist+ in between my port inlet and #2 but can't get even a fist between my starboard inlet and #1. It looks like I could probably move my ramp about .75-1" forward before it starts sloping upward. Is that the idea? Get it angling upwards as soon as possible after the inlet?
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  #45  
Old 03-02-2016, 06:44 AM
PaulR PaulR is offline
 
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Quote:
Originally Posted by alpinelakespilot2000 View Post
I too am interested. I can get a full fist+ in between my port inlet and #2 but can't get even a fist between my starboard inlet and #1. It looks like I could probably move my ramp about .75-1" forward before it starts sloping upward. Is that the idea? Get it angling upwards as soon as possible after the inlet?
Mine is the same way Steve. DanH and I have looked at it and believe that moving it forward as far as practical would certainly help. In my case, I believe I can trim some off the aft end of the inlet itself to gain a little more room. I don't remember whether I had trimmed any of the aft end off or not when I originally built it. But as it is right now there is NO way to get a fist in there. I have a buddy with an 8A and a 360 and there is a tremendous amount of room on it and he has really cool CHT's.
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  #46  
Old 03-02-2016, 07:23 AM
Jimzim Jimzim is offline
 
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I originally had only about an inch or maybe a bit more on my starboard side. I simply cut the ramp out, trimmed about an inch or maybe an inch and a quarter off the front end of the ramp, then epoxied it back in place, filled and smoothed things out, and that was it. Now I can just get my fist through the gap. So now my port and starboard ramps have similar gaps to their respective cylinders. The temp on #1 was my problem, and it dropped dramatically. Again, I don't claim to have any expertise in this area, but it worked for me. In any case, it was easy to do, didn't affect the paint finish on the outside of the cowl, and can certainly be undone easily. There is some talk of a small cooling drag penalty, but I could detect no performance change in speed.
Jim
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  #47  
Old 03-02-2016, 07:34 AM
Jimzim Jimzim is offline
 
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The improvement in my case was dramatic. My #1 cylinder temp was hitting 440 on initial climb out. I now never see more than 415 at the same point in the departure. I think the tightly cowled 7 will always tend to the warm side, but I can live with what I see now. In cruise and after leaning LOP, all 4 run below 380 at 2400 rpm. By the way, I am running an aero sport power 0-360 with 8.5 Pistons, dual pmags and an Ellison TBI, all of which I love.
Good luck, hope this helps...
Jim
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  #48  
Old 03-02-2016, 07:44 AM
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DanH DanH is offline
 
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Quote:
Originally Posted by Jimzim View Post
The temp on #1 was my problem, and it dropped dramatically..... There is some talk of a small cooling drag penalty, but I could detect no performance change in speed.
Interesting question. Did you notice a temperature drop for other cylinders? That would probably be the best indicator of an increase in mass flow.

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  #49  
Old 03-02-2016, 08:34 AM
gordon1540 gordon1540 is offline
 
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Default hot engine

Bluebread

I have almost the same tempts, have fought it for 6 months, have a o320 E2D 150 hp.

Give me a call maybe finally found problem.

Gordon
386 963 5357
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  #50  
Old 03-02-2016, 10:32 AM
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RVbySDI RVbySDI is offline
 
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Originally Posted by gordon1540 View Post
Bluebread

I have almost the same tempts, have fought it for 6 months, have a o320 E2D 150 hp.

Give me a call maybe finally found problem.

Gordon
386 963 5357
Why not post your findings here so all can benefit from your experience?
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