Compound turbo tuning

[juddski88]

I believe so. It's a JZ Mfg 63mm, got them through Brad. I originally wanted Danville and thought they were gone for good until Brad mentioned that JZ is practically a Danville turbo. I'm very curious what's Mark's tuning would be like with this turbo.

So message him and see if he will send you a base file with his vane tables for that turbo....for a fee. Either way, there are certainly ways to make it spool quickly, but it is a compromise. The 10 blade is just a bit laggy with stock injectors no matter how you slice it. Get bigger injectors and you will completed forget you had all this trouble spooling in short order.

 

[Ridin'GMC]

Bigger injectors are the next thing to add on this. Ended up having to put it back together so I could use it to take the family camping. I know my injectors are due for a replacement but its not making low rail pressure.. yet. Now I need to find out how big of an injector can the exergy sportmans can support. Couldn't do the 10mm cp3 as that wasn't in my budget at the time.

 

[Bdsankey]

The JZ VVTs are 10 blade, he (and I) won't touch anything 9 blade until quality is consistently good.

Bigger injectors are the next thing to add on this. Ended up having to put it back together so I could use it to take the family camping. I know my injectors are due for a replacement but its not making low rail pressure.. yet. Now I need to find out how big of an injector can the exergy sportmans can support. Couldn't do the 10mm cp3 as that wasn't in my budget at the time.

A sportsman realistically will handle ~625-650whp worth of fuel demand so a bit small for what that compound setup is capable of for max effort.

A set of 60% or 100% injectors would be ideal with that setup and really wake it up overall.

 

[Ridin'GMC]

The JZ VVTs are 10 blade, he (and I) won't touch anything 9 blade until quality is consistently good.


A sportsman realistically will handle ~625-650whp worth of fuel demand so a bit small for what that compound setup is capable of for max effort.

A set of 60% or 100% injectors would be ideal with that setup and really wake it up overall.

Thanks Brad. 100% is really my goal. Hopefully I'll get it next year.

 

[Dozerboy]

100% are the way to go. 60% are to small for the power your turbos can make.

 

[Ridin'GMC]

So... After a while of going back and forth on the tune trying to get it dialed in, still coming up with the same issue of falling on its face at the top end. Thinking it was the torque limiter, had it raised with the help of member on here, it's still falling on its face at the top end. Now I'm thinking it may be more of a fueling issue, even though the rail pressure is still holding at 24k psi. Is it possible the fuel line may be collapsing, even with a lift pump? Or more likely from injectors returning too much fuel at WOT? I'm suspecting injectors as I reused the original 267k mile injectors. It's not hazing or running rough.

 

[2004LB7]

If you have pressure you have pressure. Look elsewhere

 

[Ridin'GMC]

If you have pressure you have pressure. Look elsewhere

What else would be limiting at the top end. First I thought it was the torque limiter so made some adjustments, and it's a little better but still the same issue. Something is pulling back and I'm unable to figure out by looking at the logs.

 

[Bdsankey]

What are you commanding for vane position at WOT when it starts to fall off?

 

[PureHybrid]

So does the mm3 or even injector pulse show a drastic decrease when you think it's falling off?

 

[2004LB7]

Post the log up

 

[Ridin'GMC]

What are you commanding for vane position at WOT when it starts to fall off?

From watching on my insight gauge it'll drop down from 65-50 to 23% and hold there since that's the set minimum vane position.

So does the mm3 or even injector pulse show a drastic decrease when you think it's falling off?

On my last tune which was my last log before I made adjustments to the torque limiters, it'll drop down to 70mm³ and hold there.

Post the log up

Definitely will do sometime this week when I find time to log it with the current tune it's in now.

 

[Ridin'GMC]

Finally got around to doing a new set of logs. See what you guys think might be the issue. You may notice on the vane position that dropped to the low 10's, I immediately noticed that and found a discrepancy in the vane setting that was easily overlooked by me and corrected that, should be fixed now but haven't tested yet my tune I adjusted to correct the error.

 

[Ridin'GMC]

Figured I'd give an update to the thread. After several tuning changes and noticed the egt were climbing higher each time I drove, I decided to do a boost leak test and found a massive leak at the Y bridge. Wasn't too thrilled as it required me to pull the valley turbo and found oil in the compressor side. Had the turbo sent out to be inspected and I did hurt it.

Upon repairing the y bridge leak, I discovered that the factory seal whether it's a GM or Mahle seal, the seal compound not hard enough to hold the pressure in, even with 4 lower studs and torqued to 100 in-lb. After 30 psi, it would push the seal out in the seal alignment channel and cause a significant leak. That caused to erode the seal each time it leaked and got worse over time. I used anaerobic sealant on the inside next to the seal to correct the issue.

That's all fixed now and it's running much better, however having stock high mileage injectors in, I finally popped the P0087 code on a hard WOT run which is a clear indicator for high return rates. Time to save up for injectors but at least it's good enough to tow my camper, overdue for a family camping trip. Just need to do some simple MAF changes and lower the fuel pressure due to having a hard time holding speed between 75-80 mph, too sensitive on the throttle.

 

[Bdsankey]

Glad to hear it's running well again!

 

[Ridin'GMC]

Ever since I fixed the boost leak, I'm back with the dreaded P0101 even had the same issue before going twins. It only pops up when I start it, MAF g/s is around 45-46 when cold. I adjusted the MAF scaling lower around idle and it's the same. Should I be adjusting the fuel by lowering fuel pressure or pulse to correct this issue or leave it?

Also, would too high of a vane percentage (closed) cause egt to take a while to come down to 400 degrees at idle or park?

Those are the only 2 things I'm dealing with otherwise it runs good, even had to adjust the fuel limiter to control the smoke output at half throttle.

 

[Dozerboy]

Ever since I fixed the boost leak, I'm back with the dreaded P0101 even had the same issue before going twins. It only pops up when I start it, MAF g/s is around 45-46 when cold. I adjusted the MAF scaling lower around idle and it's the same. Should I be adjusting the fuel by lowering fuel pressure or pulse to correct this issue or leave it?

Also, would too high of a vane percentage (closed) cause egt to take a while to come down to 400 degrees at idle or park?

Those are the only 2 things I'm dealing with otherwise it runs good, even had to adjust the fuel limiter to control the smoke output at half throttle.

Can you set that code to not report as often based on duration? Maybe that'll fix it since it's only an issue it starts up.

 

[Ridin'GMC]

Can you set that code to not report as often based on duration? Maybe that'll fix it since it's only an issue it starts up.

I can easily enough, even though it's only on cold start ups. However, this has me interested in why it's popping the code. Too low of MAF scaling on start up? I wish it would have a snap of the parameters when the code pops up to see what caused it to come on. It does run well enough with the injectors on a high return rate. I wouldn't be surprised if the injectors are the cause of popping the code if it's not fueling right.

I found that lowering the vane percentage does help with quicker cool down before shutting down, allowing the exhaust gases to vent out quickly enough without the need to spool the turbo at idle areas.

I gotta save up for new injectors to make the truck happy and that may take a while given to the current ridiculous economy.