When installing louvers on the cowl do most install them on the bottom of the cowl or on the side of the cowl, is there any advantage in either place
Tim
May I ask why you are installing louvers ? do you have temp problems ?
we changed the oil filter housing as we could see the vernatherm was not setting with a full ring around the seat, we changed the vernatherm at the time also it help a little but at lower alt and slower air speed the oil temps rise 220 to 230 at higher alt and full air speed the temps stay 185 hope the louvers help, i will keep you postedIs this a new or overhauled engine? The reason I ask is that an IA friend of mine chased high oil temps on a low time overhauled Lycoming, installed on a RV-6, for two months doing everything possible to provide more air flow through the cooler. Finally, he discovered that the vernatherm was not seating completely and routing the oil to the cooler. He also found that not all vernatherms are created equal, they all seem to expand to different lengths at 200F (boiling water, thermometer, and caliper). He ordered 4 new units and installed the one with the longest expansion (that exceeded the original) and returned the other 3, problem solved. I hope this might be of help. Dan
i got mine from Alex http://www.rvtraining.com/html/atp/When did you get the Louvers from ? Does Vans sell them ?
So I can put them on the side OR the bottom. I think the bottom would look better as my cowls are already painted.
Allan, what models of RV is your new product designed to fit??
...If you guys with heat issues on climb-out can wait about a month, we will be in production of another product that will solve this issue. It won't be ugly, it will install very easily, won't require re-painting, won't bankrupt your budget and best of all, will not slow your airplane down. We have seen louvers really have a dramatic detrimental effect on speed as the exit air velocity is reduced, causing considerable drag. Our new product (currently in end stage testing) will not do this so you get the best of both worlds. We are seeing on long, hard climbs, cyl. temp reductions of 40 to 60 degrees and oil temps reduced 25 to 35 degrees. We have been working on and improving this product for almost a year and are now tooling it for production. If you can wait just a little longer, you won't be disappointed. Thanks, Allan...
Any update on this???
Fair go Mike, he said about a month....not a week
Installed the louvers on the bottom of the cowl it lowered the oil temps and cyclinder temps, I also disconnected the map line going to the p-mags to keep them advancing the timing at lower manifold pressure, I have only done a couple a flights with these changes the oil temps are staying around 180 to 195 so far so good,we have been fighting oil temps when the out side temp starting creeping up
in the 80s, we have sealed all bafflings, change to a larger oil cooler fire wall mounted, up at altitude at cruise the temps stay in line, but down low with warm temps and slower speeds oil temps go up, cyclinder temps are alway good up high or down low 310 to 350.. after looking into we installed the vetterman exhaust with mufflers and looking into the cowl the mufflers are pretty large and block the air flow from the oil cooler to the exit of the cowl.
with the louvers hope to have a air flow for the oil cooler ( I hope)
Tim
Over all the the oil temps dropped around 20-25 degrees i never really had a problem at cruise and the throttle wide open.. on the map i just capped off the map line and on the p-mag left the map dissconnected so when i reduce the throttle it does not advance the timing it stays set. I have a sneaky feeling this was my heat problem all along, it was advancing the ignition and heating things up when reducing the throttleTim,
I am glad you posted that....and I like what I see. I see too much advance being a problem for a lot of people, and no HP gain. It does help when LOP, but none of the EI's on the market get my mouth watering. So how much did this help? I assume you plugged the lead from the head?
Louvres on the sides should work even better. Think about the Thorpe cowls. Liquidaire Baffles........ they work for a reason. Areas of negative pressure.
...If you guys with heat issues on climb-out can wait about a month, we will be in production of another product that will solve this issue.
...If you guys with heat issues on climb-out can wait about a month, we will be in production of another product that will solve this issue. It won't be ugly, it will install very easily, won't require re-painting, won't bankrupt your budget and best of all, will not slow your airplane down. We have seen louvers really have a dramatic detrimental effect on speed as the exit air velocity is reduced, causing considerable drag. Our new product (currently in end stage testing) will not do this so you get the best of both worlds. We are seeing on long, hard climbs, cyl. temp reductions of 40 to 60 degrees and oil temps reduced 25 to 35 degrees. We have been working on and improving this product for almost a year and are now tooling it for production. If you can wait just a little longer, you won't be disappointed. Thanks, Allan...
Out of at least 100 sets of louvers that we have sold, I have not heard one customer say that they lost speed.
From Raymer, Dc = M (Vi - Vo)...cooling drag is mass x velocity loss, freestream (Vi) less outlet velocity (Vo).