Mike Nass Alien cowls 3mph gain!!!!!

[Huntfishnc]

Rocketman I am wondering the exact same thing. I have personally spoke to a couple of guys on BBC who say they are running the Mike Nass alien cowling with no ECU re-flash on a 250XS and have had no issues running lean. They have checked the plugs several times after running, but I feel a little scared to take that chance. I even asked Mike Nass himself via email and he replied back with the following: I have never heard of it... If the Eco, can't adjust for better air, there is a problem... What if someone ran with cover off... Would it blow up?... I doubt it. I also asked Joe and he said it would run leaner and could be bad. I guess if you can afford the alien cowl it might be wise to flash the ECU as well just to be safe.

Mike also told me you do get denser drier air, so with this available, the re-flash can take advantage of it and collectively makes more power.

[rocketmanjp]

I am not a speed freak, I'm just a mechanically inclined fisherman & want my motor to perform at it's best & be very reliable. I read all of DBR's blogs (many, many pages) as he was testing and developing his mods. The biggest thing that stuck with me was that the stock fuel curve has lots of lean spots in it (scary hot egt readings per DBR) at several mid-range rpm levels. DBR's remap cleans all of this up. Being that most of my running is in the mid range (4800-5500), this is what made me pull the trigger on the DBR mods. In other words, the DBR remap makes the engine more reliable than stock.

[Huntfishnc]

My original thinking was to just purchase the Alien Cowl because I love the mean look, but I am definitely going to get the DBR remap now.

[hyperflow]

I was told that id blow up my motor if i ran a alien cowl. But i talked to mercury tech when i was having my motor problems and said running it at WOT with no cowling what so ever wouldn't blow up my motor, that the ECU adj itself for the amount of air. I now have close to 100hr at every rpm range and have zero issues with stock programming and have yet to get DBR program that out performed the stock programming.

DBR is working on new programming that im testing, but as of right now stock is faster.

[cbailey]

Alltrimmedout has a 250xs with a stock Ecu that's running an alien cowling and hasn't had any problems either. If I remember correctly, he has been around 90 with a stratos/ 250xs without trouble.

[Huntfishnc]

Thanks for all the feedback and great information. Glad to hear it's possible to run it bone stock without issues.

[22520XD]

I am also running a alien cowling on my 300xs with stock programming and only thing that i am seeing is it make.my motor run a little rich because the map sensor is adapting to the extra air other than that i not having any problems. My motor has 168 hours on it.

[trapp201pro]

The alien cowl with the air box does give you more direct cool air flow the engine,the flash on the ECU may not show a lot of performance gains but it does take out some imperfections,such as lean spots at different RPM ranges that are in the stock ECU.My engine runs just a little bit richer with the ECU flash. For the amount of money that most of us spend on our boats and fishing,$900.00 for the flash is cheap if it helps an$18,000.00 engine live longer.Mercury has to run as lean as possible to meet EPA regulations,if you remember when they first came out they were called OPTI POPS.The first 1 that I had I ran as hard as you can run 1 for 10 years(250XS) It would still be running today If I had of been smart enough to have installed a set of smart craft gauges.

[Corne]

Did the engines with stock mapping still running strong? Think to do the same on my stock 300xs like the alien cowling with air plenum but afraid to lean it down

[hyperflow]

Did the engines with stock mapping still running strong? Think to do the same on my stock 300xs like the alien cowling with air plenum but afraid to lean it down

It will not lean down.

[Cgates2193]

How do you have the 300xs setup? Prop, shaft height and setback...Just bought an XRS with 300 XS with the DBR upgrades and trying to figure out where to start. Any info would be greatly appreciated!

[Corne]

So no problems with to high exhaust temperatures? Dont want a shorter life for my 300xs just want the cowl for the looks and fix the water ignestion issue

[Corne]

Found this on the website of dbr Screenshot_20180616-230531.jpg

[Tim Powell]

I would not run a cowl without a remapped ECU. These engines have no way to adjust for the extra air, they run a speed density program that is set to X amount of air for X amount of fuel....they are not MAF engines.

[hyperflow]

I would not run a cowl without a remapped ECU. These engines have no way to adjust for the extra air, they run a speed density program that is set to X amount of air for X amount of fuel....they are not MAF engines.

I checked my plugs multiple times. Was never even close to lean. Mercury will tell you it’s fine to run the engine at WOT no cowling at all. My dbr I have rich spots where it makes the motor miss, stock does not.

300xs/250xs are fine to run with a alien cowling.

[Corne]

So its still a discussion point. Don't want DBR remap just because I am located in The Netherlands (Europe) so have to miss it a long time if I send it to the USA and appox 900 dollar extra ex tax. And iam not looking for more hp just for a reliable engine and fix the water sucking @ 100+ mph (boat runs 109 mph)

[hyperflow]

So its still a discussion point. Don't want DBR remap just because I am located in The Netherlands (Europe) so have to miss it a long time if I send it to the USA and appox 900 dollar extra ex tax. And iam not looking for more hp just for a reliable engine and fix the water sucking @ 100+ mph (boat runs 109 mph)

Most are running DBR, I know a hand full of guys that are running alien cowling with stock mapping. They been running a few years with them and so far so good.

[Tim Powell]

What type of distances are you running Hyperflow? I frequently run 100+ miles at a time, at least twice a week from April to November. I did a ton of research on this subject before I modded my engine in 2016.

The guys making short runs would most likey be fine, but the guys making stupid long runs week after week like myself.....it wasnt worth the chance to me.

[hyperflow]

What type of distances are you running Hyperflow? I frequently run 100+ miles at a time, at least twice a week from April to November. I did a ton of research on this subject before I modded my engine in 2016.

The guys making short runs would most likey be fine, but the guys making stupid long runs week after week like myself.....it wasnt worth the chance to me.

I run 2 tournaments a year where i'm running around 100 miles. Most are 40 miles and under, I do approx 15-20 tournaments a year. I have ran it in really cold weather, to the point we gotta push ice off the boat ramp. Checked my plugs, still running on the rich side.

I'm not saying DBR is a bad idea, I'm just saying its not NEEDED to run a alien cowling the motor will not run lean.

[collins4]

Found this on the website of dbr

Of course they are going to say you need to run the flash if they are the one's selling it. Wouldn't you do the same to sell more of your product?