Wits End Turbo Owners (2 Viewers)

thatcabledude

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alia176

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Can y'all tell me what muffler you're using with the turbo? My Bosal muffler is over ten years old and starting to separate in places so I'd like to replace with a quiet muffler. I figure why not give the turbo a less restrictive exhaust to work with!
 
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Can y'all tell me what muffler you're using with the turbo? My Bosal muffler is over ten years old and starting to separate in places so I'd like to replace with a quiet muffler. I figure why not give the turbo a less restrictive exhaust to work with!
Oem. Nothing will be quieter than oem. Turbo and oem allows me to hear the turbo spool up.

My other 80 nonturbo has a magnaflow exhaust and it drones. Do not like it on the highway at 80mph. Too much noise for me.
 

alia176

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Thank you gents for the feedback. I have a sweet resonator at the end so it took care of the awful drone that the Bosal muffler produces. So, it's OEM and Magnaflow so far. My exhaust is super quiet but I still can't hear the turbo spool up . On the other hand, I'm not hitting 7psi either so that could be the reason. :bang:. I'm hitting 5spi max and wanted to make sure that my old muffler isn't causing unnecessary back pressure. Curious what others are running.
 

NLXTACY

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Thank you gents for the feedback. I have a sweet resonator at the end so it took care of the awful drone that the Bosal muffler produces. So, it's OEM and Magnaflow so far. My exhaust is super quiet but I still can't hear the turbo spool up . On the other hand, I'm not hitting 7psi either so that could be the reason. :bang:. I'm hitting 5spi max and wanted to make sure that my old muffler isn't causing unnecessary back pressure. Curious what others are running.

need to figure out why. Most are seeing 7psi. Mine maxes out at 7psi when I push it.
 

alia176

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need to figure out why. Most are seeing 7psi. Mine maxes out at 7psi when I push it.

I'll do some systematic troubleshooting but so far, I can't seem to pull any of the high mountain passes w/o flogging the crap out of her. Last weekend, it was second gear, spinning around 4,000 rpm in order to barely hold 50mph :bang: At that RPM, I was pulling 1psi of boost. Third gear couldn't hold the hill to save my life.

Things I've checked thus far:
- correct color springs in the wastegate
- all T bolt clamps seem to be tight but no way to really know if I'm having a boost leak in that short pressurized run between compressor output and TBI input.
- no exhaust leak that I can find and all exhaust hardware is tight.
- I'd like to use another pressure gauge just to confirm my Bosch boost gauge is indeed accurate.
- too much backpressure from an aging muffler, maybe? Otherwise, I have 2.5" in/out Magnaflow cat, 2.5" mandrel bent up/over frame then hit the Bosal muffler which I believe is factory size of 2 1/8" but not sure. There is an aftermarket resonator at the tail pipe.

Here's a video I made while driving from my house:
 
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Hmm yeah you are a couple psi short. How steep is that hill? In that video you are pulling the hill at 90mph. How much faster do you want? lol.

I'll do some systematic troubleshooting but so far, I can't seem to pull any of the high mountain passes w/o flogging the crap out of her. Last weekend, it was second gear, spinning around 4,000 rpm in order to barely hold 50mph :bang: At that RPM, I was pulling 1psi of boost. Third gear couldn't hold the hill to save my life.

Things I've checked thus far:
- correct color springs in the wastegate
- all T bolt clamps seem to be tight but no way to really know if I'm having a boost leak in that short pressurized run between compressor output and TBI input.
- no exhaust leak that I can find and all exhaust hardware is tight.
- I'd like to use another pressure gauge just to confirm my Bosch boost gauge is indeed accurate.
- too much backpressure from an aging muffler, maybe? Otherwise, I have 2.5" in/out Magnaflow cat, 2.5" mandrel bent up/over frame then hit the Bosal muffler which I believe is factory size of 2 1/8" but not sure. There is an aftermarket resonator at the tail pipe.

Here's a video I made while driving from my house:
 

alia176

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Hmm yeah you are a couple psi short. How steep is that hill? In that video you are pulling the hill at 90mph. How much faster do you want? lol.

The video is on the frontage road at my house, not the hill from last weekend. I've been over few CO mountain passes, usually over 8,000' and not able to hold them. Going over Vail pass was 2nd gear, 4,500rpm and barely holding speed.
 
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The video is on the frontage road at my house, not the hill from last weekend. I've been over few CO mountain passes, usually over 8,000' and not able to hold them. Going over Vail pass was 2nd gear, 4,500rpm and barely holding speed.
That doesn't sound normal. My Turbo 80 can do 100 no problem and begging for more speed. I've done hill climbs at 80 mph no problem. However, I'm not afraid to step on the skinny peddle all the way down. I drive all my cars and trucks like I stole it. Only way to drive!

Edit: I towed my half cut yota trailer camping about a month or two ago up and down Pacheco pass Hwy 152. Elevation is not super high but it's got some steep parts. A non-turbo 80 can do about 80-90 not towing and 65-70 towing if you're on it. I was probably around 8000lb 80 and 1000lb in the trailer. Pulling at cough 80mph at some stretches to see what she could do. Truck pulled it like I had nothing behind me. I wasn't pushing it hard either, maybe 80% throttle.
 
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alia176

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Timing getting pulled?

I thought about that but would that impact the turbo spooling up? The engine is still spinning like a mofo, which is what the turbo needs to see, regardless of what the ECU is trying to do. Of course, I could be talking out of my arse..... Is the wastegate being told not to exceed 5psi, somehow?
 
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I thought about that but would that impact the turbo spooling up? The engine is still spinning like a mofo, which is what the turbo needs to see, regardless of what the ECU is trying to do. Of course, I could be talking out of my arse..... Is the wastegate being told not to exceed 5psi, somehow?
Mine generally does 5.5psi. The highest I've seen mine is at 6-6.2PSI floored from 0 to 100. I have not seen any higher than that.
Brand new rebuilt engine but on factory cats and factory exhaust. I'm wondering if it's my restrictive exhaust...
 

Zjohnsonua

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I thought about that but would that impact the turbo spooling up? The engine is still spinning like a mofo, which is what the turbo needs to see, regardless of what the ECU is trying to do.

Sort of... The turbo needs a blowdown event caused by load in order to spool up. This is why you can't pin the throttle in park or neutral and watch the boost spike. Asking for power under load will net boost gain until the gate opens, the compressor goes into surge (really bad), you choke the compressor from inadequate air supply, or the backpressure marginalizes the blowdown. Either of the latter two can cause the turbo to puke oil into the compressor side. You might pull the charge plumbing and see if oil is present.
 

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