Wits End Turbo Owners (7 Viewers)

[Wompom]

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...

Same here - 20k old motor, factory 2nd cat, magnaflow first.
Topped out at 6.2 under load, occasional spike at shift (doesn't really count).
I'm not concerned with the lack of .8, but makes me want to try a new 2nd cat/replace the old exhaust/2nd o2.

 

[NLXTACY]

I’m seeing 6.4 regularly and 7 if I really push it uphill. I’m about to put on new cats. Curious to see if there will be any affect.

 

[Zjohnsonua]

It'd be very informative if you could get a pressure reading in the downpipe before you make the change. Gonna need something that measures in inches of water.

 

[spyduh]

Same here - 20k old motor, factory 2nd cat, magnaflow first.
Topped out at 6.2 under load, occasional spike at shift (doesn't really count).
I'm not concerned with the lack of .8, but makes me want to try a new 2nd cat/replace the old exhaust/2nd o2.

same i'm not worried about the .8. It's plenty freaking fast as it is. I'll eventually get new magaflows when my cats burn out. But no need in spending money on something that aint broke and fails smog yet!

edit: one thing I would love is if someone could do a straight "test" pipe and then provide some boost numbers. I wonder if that would free it up and spool up higher.

 

[scottryana]

No need to wonder. It would.

same i'm not worried about the .8. It's plenty freaking fast as it is. I'll eventually get new magaflows when my cats burn out. But no need in spending money on something that aint broke and fails smog yet!

edit: one thing I would love is if someone could do a straight "test" pipe and then provide some boost numbers. I wonder if that would free it up and spool up higher.

 

[Zjohnsonua]

^^ x2. having pressure numbers to go along with boost numbers would be very good to see.

 

[alia176]

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.

I see oil present in the compressor but thought that's coming from the PCV.

 

[alia176]

It'd be very informative if you could get a pressure reading in the downpipe before you make the change. Gonna need something that measures in inches of water.

I can come up with a slack tube manometer if needed. Just measure the pressure inside the pipe vs outside? I was thinking of doing the same on the muffler, before and after but that'd require some doing.

 

[Zjohnsonua]

I see oil present in the compressor but thought that's coming from the PCV.

I can't see where you routed your PCV, but if it's on the compressor intake side then it's likely to be a source. The tell tale is if you pull the comp cover off and see oil spray behind the wheel (it'll look similar to a failed rear main).

I can come up with a slack tube manometer if needed. Just measure the pressure inside the pipe vs outside? I was thinking of doing the same on the muffler, before and after but that'd require some doing.

Yes, after the turbine but before the cat. That's all the turbine sees.

 

[scottryana]

I am not at all worried about backpressure. You are confusing a turbo not being able to make more boost because it has too much back pressure and a system being regulated by Wastegate spring vs back pressure.

this system is not under any stress. The turbo is plenty large for flow. It is simply a little more back pressure in some of these old exhaust systems will cause the wastegate to open earlier since it has no boost controller.

^^ x2. having pressure numbers to go along with boost numbers would be very good to see.

 

[Zjohnsonua]

Thus far there haven't been any performance numbers assigned to any part of the system, just complaints of ill performance. Without knowing what is happening where, I don't think it's safe, or fair for that matter, to assign a failure cause.

 

[scottryana]

what performance numbers are you looking for, there have been many.

Thus far there haven't been any performance numbers assigned to any part of the system, just complaints of ill performance. Without knowing what is happening where, I don't think it's safe, or fair for that matter, to assign a failure cause.

 

[spyduh]

Thus far there haven't been any performance numbers assigned to any part of the system, just complaints of ill performance. Without knowing what is happening where, I don't think it's safe, or fair for that matter, to assign a failure cause.

There hasn't been any complaints about the Turbo that I'm aware of performance. The Turbo hands down lays power down to the wheels. It's night and day difference between the 2. I have 2 80s in my garage now for direct comparison and they are in no way near the same. It's got enough power to get yourself in a stupid situation. Ask the SEMA test driver who rolled the test mule, I bet he'll vouch for the performance of the Turbo. ROFL!

 

[alia176]

There hasn't been any complaints about the Turbo that I'm aware of performance. The Turbo hands down lays power down to the wheels. It's night and day difference between the 2. I have 2 80s in my garage now for direct comparison and they are in no way near the same. It's got enough power to get yourself in a stupid situation. Ask the SEMA test driver who rolled the test mule, I bet he'll vouch for the performance of the Turbo. ROFL!

Are you able to do a short video of the boost gauge vs RPM by any chance? I'd like to know how the system is "supposed" to behave as this is my first turbo rig!

Thx.

 

[Zjohnsonua]

Not saying the turbo is at fault - it works too well in most installs. I'm saying that having those measurements would help owners with lower than expected pressures and/or performance figure out what's going on to get their truck sorted out.

 

[spyduh]

Are you able to do a short video of the boost gauge vs RPM by any chance? I'd like to know how the system is "supposed" to behave as this is my first turbo rig!

Thx.

my boost gauge and speedo are in different locations. I run a delta console. I have some videos. PM me and I'll share them with you.

 

[duggy]

I’m seeing 6.4 regularly and 7 if I really push it uphill. I’m about to put on new cats. Curious to see if there will be any affect.

What cats are you going with? I'm really tired of my cats rubbing on my slider, so once I pull it off, I'm going to address everything on the exhaust

 

[NLXTACY]

What cats are you going with? I'm really tired of my cats rubbing on my slider, so once I pull it off, I'm going to address everything on the exhaust

im limited so using the CARB approved MagnaFlow

 

[alia176]

What cats are you going with? I'm really tired of my cats rubbing on my slider, so once I pull it off, I'm going to address everything on the exhaust

This is related somewhat to the question of which cat. I'm in NM so I opted for a "federal" cat from Magnaflow, even though my hood sticker says CA epa certified. Well, lo and behold, i threw a "catalyst below threshold" on the O2 sensor post cat. This is for informational only and this second O2 sensor isn't used for engine control. But, it was interesting that my ECU is programmed to accept only CA EPA certified Cat I ended up doing the O2 eliminator circuit using a resistor and a cap or some such thing years ago.

 

[Dirty Koala]

A lot of progress has been made on my Air to Water intercooler system.

The expansion tank / Meth tank holds about 3.5 gallons of fluid and uses up all the available space where the ABS pump was back to the firewall. There is still enough room to get my arm in to change the oil filter though. I had an -4AN bung welded in and capped off for future Meth Injection use. The Inlet/outlets are all -10AN.

The original plan was to place the intercooler on top of the valve cover with simple short end tanks made in line with turbo outlet and intake manifold, but hood clearance became an issue. I am sure this could still work if you are using a smaller IC core. The Garrtet core I am using is good for 750hp, so it’s not small.

The new plan was to put it in front of the turbo between the York and valve cover with some more complex end tanks. To accomplish this, the York bracket needed to be cut and dropped 1.5” and a new Heater bypass tube had to be made to take advantage of that created space.

I am definitely taking advantage of every last ounce of space under this hood, but I am really happy with how this is coming together. I still need to run the fluid lines and wire up the pump and heat exchanger fan that is mounted in front of the condenser on the passenger side.