How much boost are you pushing with your 1hdt's CT26?

[TuffMudder]

I'm asking specifically about 1hdts with the ct26 turbo.

I'm currently running conservative at 11-12psi, but I'm in the process of getting a 3" exhaust and intercooler. I'm curious how much boost others are getting out of theirs,with or without modification, while still keeping egt's in check.

Thanks

 

[mudgudgeon]

14-15psi is considered to be the safe limit.

Above 15psi, you get loads more turbo noise, but not a lot more power. Gains disappear fast after 15psi, and loads more fuel is needed to push it there.

I ran mine well above that for a while experimenting when there was not a lot of info available on tuning these engines, eventually blew up the turbo at 22psi
If you want more power than you can make with a stock turbo at 15 psi, it's time for a new turbo.

 

[TuffMudder]

I only plan a small bump on mine up to 14psi, i was just curious if others had had success above that

 

[mudgudgeon]

Above that the turbo is beyond its limits, both performanxe wise, and physically.
You can get a bit more from them, but it's less and less efficient, takes more fuel, and adds more heat to the intake air charge to produce little gain.
Very rapidly diminishing rate of return.

Then there's the risk of the compressor wheel exploding. Mine did and the result was a full engine tear down and rebuild

 

[TuffMudder]

Thanks @mudgudgeon

 

[IanB]

I'm currently running 18psi on my stock turbo, dialed back from 22psi when I had a shop tune it (ran it like that for a year before I dove in and did my own tune). My tune runs much better than the shop's tune, and should be safter as well. @mudgudgeon gave good advice above regarding the safe limits of the stock turbo.

Gturbo Grunter Extreme is sitting on the workbench waiting for me to install it.

 

[TuffMudder]

@IanB if you have a grunter going on, I think its important for me to tell you, you're going to need a custom airbox with 4" going in and out either open in the fender or with a 4" snorkel if you really want to get the most out of it. Trust me!

 

[mudgudgeon]

@IanB if you have a grunter going on, I think its important for me to tell you, you're going to need a custom airbox with 4" going in and out either open in the fender or with a 4" snorkel if you really want to get the most out of it. Trust me!

How would you know?
great thing about these forums, everyone has a chance to learn from other people's F ups, success and failures and trust me, I've added my share of lessons for people to not repeat

 

[ZeGerman]

@IanB if you have a grunter going on, I think its important for me to tell you, you're going to need a custom airbox with 4" going in and out either open in the fender or with a 4" snorkel if you really want to get the most out of it. Trust me!

@IanB since by the looks of things you will be needing to sell the Grunter, please PM me. Ill take it

And to stay on point to this thread, I top out at 18PSI. Generally hanging around the 15 PSI range. 8000 miles so far no issues.

 

[Tapage]

I did push mine up to 20 PSI back in the day with no mayor gains as stated here before .. went back to 14, add intercooler ( A to A ) push it up to 16, then jump to the hybrid from supra compressor side and with that mod stays in 18 PSI until replace it .. all the gains and cons, but more important the upper limit ain't never be a straight rule .. it will depends on your fueling / tune and your ambient temps ..

 

[Ringwraith]

@IanB since by the looks of things you will be needing to sell the Grunter, please PM me. Ill take it

And to stay on point to this thread, I top out at 18PSI. Generally hanging around the 15 PSI range. 8000 miles so far no issues.

This is exactly my boost setup. My manual boost controller is set to 18, but I try and keep it around 15 as well. I rarely go over 15 because it doesn't do a whole lot more. I`m running an ebay turbo though, as my OEM one exploded 3 days after buying the truck, and about 1000 miles from home :/ Put almost 20k miles on the ebay turbo though so far and still runs great!

 

[TuffMudder]

Thanks for all of the responses. Makes me much more comfortable with my plan. I'll have a new intercooler and possibly a 3" dump and exhaust (still looking for someone to do it), so my plans to go to (now) 15 psi should allow me to get all I can from the stock turbo without pushing any limits or (I think) significant adverse effect on the durability or reliability of the engine

 

[dan1554]

At 14psi on the stocker, the intercooler would be hot to the touch after a hard incline. After installing a modern turbo, it’s pretty much ambient temperature. Egts are way down. Echoing what everyone else said, I wouldn’t push it much further. Even at 14 there’s a lot to be desired.

 

[TuffMudder]

@dan1554 What turbo are you running?