Scotty air - grudging acceptance

[Darel]

OK, had my first decent towing trip with the Scotty installed. Some of you may remember the thread I started last week about not liking it. Well, I guess it's going to stay around for a while. Pulled a 4000-lb+ trailer 3. 5 hours, up and down some very long and steep grades, and maintained highway speeds (70+) pretty much the whole time, except twice when I backed off just to save the transmission, which is not DTTed yet. 75 mph, most conditions, 800 deg. It might have hit 1000 on longer, steeper grades, but the coolant temp was over 200 by this point also. I'm not counting the WOT bursts to pass octogenarians in their Buicks. Pre-Scotty the truck was around 800-900 unloaded just to maintain 70.

This doesn't mean I wasn't glad to shut it off, though. Dear God, that noise is heinous, especially at highway speeds under load when that turbo just starts whistling away. Has anyone tried lining the cowl space with Dynamat to reduce the noise somewhat? I'm not even sure if it's waterproof, but I thought it might be worth a shot, just to save my hearing.

Darel

 

[illflem]

I've just lived with sound of my Scotty but have thought if a guy wanted to quiet it down he could block the area between where the 4. 5" hole enters the vent intake channel and where the vent intake enters the cab. My thought was spray type foam insulation would work well, make forms to contain it where you want out of waxed cardboard. The black plastic screen removes easily. You will notice if you turn your climate control to recirc the noise fades because the vent intake door to the outside is closed. Blocking the area I described will do much the same thing only better. Did you make sure your turbo silencer ring is installed? Scott says don't use his unit without one unless you are a glutton for pain. The Scotty noise isn't so bad with the window down and I've found from Oct-May the extra cold air isn't necessary, my factory airbox goes back in for the time when it's nice having the windows up. Did you move your pyro probe back to post turbo? Your egts seem too low for pre and approaching too high for post.

 

[Oliver88]

I've had my Scotty over a year and love it for towing. Keeps down the EGT's. You are right about the noise. Need to be worked on. I guess we sacrifice the noise to keep down the EGT's. Let me know if you come up with a solution. I think I'm going to change out the K&N for an AFE filter. I think it looks tougher. Just my opinion.

Greg

 

[SlyBones]

Did you actually drill the hole in the firewall and all that?



I have heard some good things about LarryB's SS turbo shield. For $15 and shipping you may want to install one of those, and then try the filter with the shield and w/o the plastic housing.



Give us a report on the noise difference and temps difference. Maybe you could only use the housing for towing and leave it off for daily driving. Depending on how hard it is to install of course.



Just suggestions.

 

[Darel]

Yup, I drilled the hole. Where is this silencer ring? I didn't have any leftover parts (like I usually do ) when I was done. The turbo never made noise before, so I'm guessing it's still in there.

I though about making a little wall like you say, but then I thought the whole point of the intake was to suck huge amounts of air from the cowl, and I didn't want to prevent it from doing that. I'll try the recirc thing, never even thought of that.

BTW, the pyro is still pre-turbo. .

Darel

 

[SlyBones]

The silencer ring is in the inlet to the turbo. Looks like a snap ring, is inside the inlet right in front of the compressor blades.



I think there are 2 things going on with these filter mods. More air and colder air. The experts can enlighten me.



Yes the plastic housing is designed to give colder air by drawing it from outside and not from under the hood. Both the new AFE and K&N setups provide heat shields that shield the hot air from the turbo and engine from the air filter. For older systems you can get a JRE shield from Jannetty Racing. And for the BHAF MoparGuy filters, there is the Mallory Mount to do the same thing. -- In the end the goal is colder air.



LarryB makes a shield that fits on the turbo. Very inexpensive, but does require you to tap 3 holes on the compressor housing. I recently talked with one TDR member who had a JRE shield. Removed the JRE shield and installed Larry's turbo shield. Said it worked just as well or better. Nothing against the JRE shield, just pointing out Larry's shield does work on BOMBed RAMs.



Just an option to try so you can keep the filter you already paid for, lower the noise, still get EGT reductions and not spend a ton more money that you already did.

 

[illflem]

Darel, I talked to Scott about making the cowl wall, he thought it was a good idea. I don't think that it would cut off the intake air much but the unknown is what it might do to your vent air. Maybe experiment with a rag first, just make sure it won't get sucked up into your intake. Hold it with some wire?



The silencer ring is just inside the intake to your turbo, you can see it by removing the hose. It's hard to describe what it looks like without one but if there is a large snap ring missing just inside the turbo the ring is gone. This is situation where a picture comes in handy.

 

[Hammer]

Scotty Air Question

Ok,maybe you users can answer this for me and trust me I'm not looking to start an arguement,but I have a legitmate question,,On the heels of our most recent dyno meet one of the trucks had the Psychotty Air box and filter system on a truck using one of Piers new turbo's,,While she was spinning on the roller under power and big boost it was quite evident it was collapsing around the filter BIG time ,,Now what my question is here(keeping in mind I am shopping for a better air box system),Is this a problem others are having or maybe a isolated incedent???,,Kinda scary when it was seen by the members in attendence,,Collapased air box + severely hampered air flow + big fueling = MAJOR MELTDOWN to me,,Anyone watched theirs while spinning or underload and is this common??

 

[SlyBones]

I dont think the air filter collapsing is isolated. Others have reported this. Both the new AFE and K&N system are designed with deeper pleats to add strength and prevent collapse.

 

[Hammer]

OK,maybe I wasn't clear on this,,It was not the filter inside collapsing,but,the outer air box around the filter being sucked onto the filter that was restricting air flow,,I understand that this could happen with the high boost levels,but,is this normal for this box??,,Just searching.....

 

[illflem]

Hammer, I've heard of the K&N collapsing if it's been dented. The outer plastic housing will supposedly only deform if the opening on the turbo end of the Scotty's housing has been blocked off. Scott warns against doing this, but many folks don't pay attention.



The Scotty was great when it came out but now there are better options in the same price range. The new K&N housing looks good as does the Valiant. There were recent threads about these new housings in the products forum, but as usual a search is useless.

 

[JohnE]

Hammer has brought up a good discussion point.



The Scotty (Psycotty) is designed and installed to take use ram air via cowl induction. The basic principle is to keep the relative air pressure on the outside of the air filter higher than the air pressure leading to the turbo compressor inlet AND higher than the ambient air pressure outside of the aircleaner housing. Sort of like supercharging the turbocharger... .



Let's think this one out loud.

Truck runing on dyno and tied down to rollers

no air flow and therefore <b>no</b> cowl induction.



Sure makes sense to me that a free flowing air filter and high air flow will create a low pressure situation inside a Scotty housing enough to collapse onto the filter cone.



Maybe one should remove the housing and let the filter breath free when running on a dyno?

The AFE, BHAF, and K&amp;N units do this ... by simply opening the hood?





My 2 bits;



-John

 

[Darel]

Dammit, I still have my silencer ring.



Illflem, I tried the recirc thing and no difference. Therefore I doubt it'll be worth my while to wall off the cowl. Thanks for the suggestion, though. Guess I'll just go buy some earplugs.

Darel

 

[LarryB]

Originally posted by SlyBones



LarryB makes a shield that fits on the turbo. Very inexpensive, but does require you to tap 3 holes on the compressor housing. I recently talked with one TDR member who had a JRE shield. Removed the JRE shield and installed Larry's turbo shield. Said it worked just as well or better. Nothing against the JRE shield, just pointing out Larry's shield does work on BOMBed RAMs.

The latest ones shipped include self tapping screws as well as the standard 8-32. These work well and only require drilling but no tapping. Much easier! I have also produced some aluminum shields for those who don't like the shine or want to paint them to match. www.fostertruck.com/dodge



Larry

 

[Pthomas]

bug shield? no cowl induction!!

 

[Hammer]

Good points... ...

-I agree with the blocked off area helping to do this,BUT,the owner had removed the box from the cowl and we all could plainly see it was not blocked or restricted and his filter was not bent or perviously damaged

-Next was the lacking of forced air not allowing the cowl to function and a improper vacum situation,,They address the air flow issue with a extremely large fan in front of the truck(no I do not know how much cfm it flows but its close enough to simulate road conditions and allow the intercooler to function properly)

I agree that removing the outer case would be a good thing to due on a roller spin,but,come on here gang,we all know we can duplicate roller conditions on the highway easily and that brought on my rampant rumblings in my head,,Just made me wonder if anyone else had seen something like this thats all.