Scotty II w/ hole cut turbine whine

[RSnaith]

Originally posted by rubberneck

I just couldn't take it and benched the scotty. I run a Mega cannon now and love the sound of the B1.

Just a quick note for those who can't handle the Scotty in dual inlet mode: The Scotty II in HUSH mode (cowl hole covered up) is as effective at reducing EGTs as an open, oiled element with a heat shield, and its quieter too. You don't need to spend your money twice on another air system (I got lucky. My lady loved the sound of a dual inlet Scotty with a B1 )

 

[RustyJC]

Bob,



I got to thinking last night. Once the flow is straightened, then one needs to look at the turbo compressor inlet. Just like a gas turbine or jet engine, we really need a proper bellmouth to get the air smoothly into the compressor - think "silencer ring" (although that's a darned crude excuse for a bellmouth). I don't know what some of the bigger turbos look like in the turbo inlet area, but they may be prime for some silencing via the bellmouth/silencer ring approach.



Rusty

 

[rweis]

I'll try to take some pic of my B1 inlet. I have to do film, develop it, scan it, and post it (never posted here either), but might be interesting fo others to see.



I TOTALLY agree with RSnaith. The Scotty II in hush mode (the way I am running now) even with the B1 (which is fairly loud), I can just hear it. I have not driven it loaded, this weekend will be the 5er RV test, but will soon find out. With the windows down the road noise drowns out the turbo. The Scotty II in hush mode works REALLY well.



I am not going to "bench" my Scotty II. I'll run it in hush mode and figuer out the B1. The Scotty II is doing what it is suppose to and I am totally pleased with it's filtering, air handling capabilities in hush mode.



There is a link a couple of post above about an inlet flow straightener. It might be on iteration #1 of going public. That might be part of the solution. These things are never totally solved with a single answer. I think it will be a combination of sound padding under the hood (not done yet), maybe a sound barrier 2 or 3 sided enclosure around the turbo (not done yet) , Scotty II in hush (runs GOOD), inlet flow straightener (just comming on the market), not corregated turbo inlet pipe(PVC?), and ???



Rusty has thoughts on the flow straightener concept. Maybe 2 of the new flow straighteners like the top and bottom of a soda can in some sort of frame?



There's some workable combination, just have to find the combination that suits you. Each of us even has different auditory capabilities and one may hear the turbo loud and clear, and another may not hear the turbo at all, and that's another variable.



ATBGO (And The Beat Goes ON)



Bob Weis

 

[rweis]

update



towed 8k tall profile 5er, current power = stock injectors, Scotty II hush mode, KSB1B, ATS manifold, RIP's 4".



boost 8 - 22 # (stock injectors did not generate more than 22# all day), egt (pre) 750 - 950*, 55 - 60 mph, flat (florida), cruise controll most of the day.



as the boost went up the whine became less (higher pitich?, greater air flow?), not objectionable at all without ear plugs. wife even did not mind at all. tried the "Quiet Ear" for about 2 hours and had normal conversation, normal radio, slightly reduced road noise, no whine at all, none.



power

cruise control generally maintained 55 - 60 (ran some at 55, ran some at 60). one hill could not maintain 55 and dropped to 53. KSB1B spool was right there all day. KSB1B spools very nicely. realize that there is probably not enough fuel for sufficient hp with this setup, should be pleanty of air.



just wondered how it would act with stock injectors. not bad, very comfortable, just a tad underpowered for flat florida.



FYI,



Bob Weis



next tow is with DD2's in about 3 weeks

 

[Forrest]

To the top ... anybody have any updates?





thanks

 

[scotty1]

Did not see the latest on here...

Thanks Rod for telling me that folks are still discussing this here.



I have tried several of the things mentioned here to reduce and/or eliminate the noise. No luck so far.



I have the B1KS and under load its not as bad as empty rolling down the highway at 70-80 MPH. Not sure why either.



That cowl is made up of some light cavernous metal. I hate to say this but the cowl appears to be the chamber that makes the noise so apparent and when the engine takes more air, the cowl gets less of the air/noise. I have tried several different kicks at the cat and to no avail.



The idea of straightening the air is great but the cowl is still there.



I think about the possibilities of getting this noise reduced often... so far no luck. :{

 

[illflem]

Turbo Air Guide

The great guys at Diesel Power Products are letting me test one of their TAG units http://www.dieselpowerproducts.com/tag What it does it straighten out the airflow to the turbo.

So far we have run the unit on three 12 valves and one 24 a minimum of 2000 miles each. Most testing has been done pulling 10k plus travel trailers for half of a round trip on the same route. With careful record keeping, known hills and loads there has been no mpg, power gains or lowered egts. There has been about a 1-2 psi drop in cruising boost and quite a large drop in turbo whine. The DPP guys have reported better results with '03s and PSDs. It will only work with turbos designed to accept a silencer ring and takes about five minutes to install. All the folks who have tested it question whether the price justifies the decrease in whine. No one begged to to put it back on nor said they wanted to buy one. If the price came way down maybe.



This device is still being fine tuned, it may be awhile before perfected but has great potential.



#ad




For those who think this may restrict airflow, it only looks that way due to the angle of the picture. Looking at it straight on you can barely see it, the material is very thin.

 

[WadePatton]

For those of us still running itty bitty turbos, does the silencer ring make any difference?



Where's Greg--the Noise Nazi? Somebody send him a Scotty 2 and a holesaw! See what he can do with it.



I don't see how insulating/isolating in the cowl can NOT reduce the noise. But I s'pose I'll find out when I get one.

 

[JGK]

Illflem,



I guy showed up to our dyno day last fall with a TAG someone had given him to try. He did a run or two with it in and a couple with it out. Lost a few ponies with it in. It was filed in the "round file".



We didn't notice if the turbo whine was quieter with it in.



-Jay