I just picked up my '87 SR5 Turbo a week ago in TX. It has a Marlin W56-B manual. The PO had put a tiny exhaust and no cat on it and it was really loud from idle (900 RPM) up to 3K where it became quiet. So the first thing I did was try to quiet it down with a Flowmaster 50 and a new Flowmaster cat (both very affordable via Amazon).

The new setup fit great and idle sounded quiet and almost a little throaty (if that is possible for a 4 CYL). Then I drove it and it still has a loud almost ear piercing pitch from 1-2K but is quiet at idle and from 2k+. And I can finally hear the Turbo working over 2K for the first time.

It's loudest when I first launch and when I shift a little low in the power band (between 1-2K). If I shift perfect from 2nd on and keep it above 2K all the time, I can limit or eliminate the ear piercing noise.

Is is this normal for a 22R-E? Or do I have a backpressure issue somewhere. It has a K&N air intake if that helps. Otherwise it's stock with 112k miles, only 10k since the 22R-E rebuild, and 2K on the tranny (brand new!).

Any ideas? My wife did not hesitate to point it out...again!

(old exhaust in first two pics below and new setup in the 3rd pic)

 

It is a thirty year old 4x4 with little to no sound deadening. At 3000 rpm the tires drown out the exhaust on mine probably the same for you...

Can't help you I've got a twelve inches pipe sticking out the fender my gf says it sound like an airplane.. And the little girl I drove past last week that covered her ears confirmed it..

The turbo should be the biggest source of back pressure. Check ffir exhaust leaks at the manifold.

 

It's actually really quiet at 2-3K RPM (it has 31" street tires...for now, so they are quiet). No leaks at the manifold that I can find. But the drone from 1-2K definitely makes you want to wear ear plugs. It's not a high pitch engine revving sound, but instead a deep low decible one that just plain hurts.

If its normal, just more reason to do a 3.4L Swap...

 

If you can, post a video of the noise.

My 22R (no turbo) is noisy but nowhere near ear piercing. It gets louder as the RPMs increase.

Something is definitely wrong to create a noise like you describe.

 

To look for leaks I put a table spoon or so of automatic transmission fluid in the Plenum and start it up. Have someone to block of the exhaust pipe and look for smoke coming out of the pipe. I dont know the turbo much but on the 22re, They like to leak at the manifold to the head, they "Y" pipe to where it connects to the single pipe likes to crack out a lot.

 

Thanks. The best way I can describe it is the tone is similar to the tone you hear from a UPS/FedEx truck first taking off, but more ear piercing. And it's mostly from 1500 - 2000 RPM.

 

Thanks. It doesn't sound like a leak or exhaust screaming through a small hole. It's a deep tone that is consistent from 1500 - 2000 RPM. And it also backfires when downshifting in that range too if that helps. Most simliar to a high torque UPS size truck first taking off, but worse on the ears.

 

im willing to bet the turbo is shot. take the turbo off and take a look to see if the housing is cracked,

 

Does this help or do I literally have to take the Turbo off to see?

 

youd have to take it apart to see. itd be cracked on the inside between the wastegate and the impeller.

 

Ok. If it was, how much do replacements run and do people usually upgrade instead of replacing with a stock one? I don't know much about Turbo's.

 

You need to drop the exhaust pipe from the bottom of the downpipe, that is the small elbow section in your photo with the oxygen sensor sticking out. Then pull the elbow/downpipe off the back side of the turbo. Below is what you do not want to find.

Radial play, measured at tip of vane at 9 o'clock. Touching , zero clearance!
This one was cracked and the bearings worn bad enough to impact the housing on both ends, compressor and impeller damaged.

The proper housing can be very hard to find, on occasion you can find a batch out of Asia.

The diesel and celica ones are easily found, but these point the exhaust out the fender instead of down.

Cxracing produces a kit with turbo and a new exhaust section that uses the "wrong" housing.

There is an eBay seller, that I forget the name of offhand, who produces a turbo outlet/adapter with a vband that lets you build your own exhaust intermediate pipe and oxygen sensor mount.

Lce produce a kit with an "upgraded" turbo and related parts to replace the CT20 with a Garret.

At any rate untill you remove the heat shields it would be near impossible to locate any gasket leaks. You would want to try and feel for it before it gets blistering hot. It's also worth noting that the exhaust manifold tends to crack on the underside between engine and manifold.

I've mentioned, I think, my stubby exhaust? I can hear the turbine/compressor at idle all they way up until the symphony of parts gets to a dull roar.

It is worth noting it is a low compression turbocharged engine, and sounds a bit "boggish" untill you hit a positive manifold pressure. A cracked turbine housing will increase the turbo lag time, no boost untill much higher in the RPM band. Which might be what you are experiencing.

You can maybe post a video of the issue. Phone audio pretty much sucks but it is generally better than nothing.

 

Also worth noting!
the open element K&N filter increases the noise of the intake.
Extending the exhaust outside the bodyline will also quiet it down, and as a benefit reduce the risk of death from sucking down exhaust fumes...