The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

[AussieHJCruza]

In which case you’d want 6… which is ideal

I don’t see too much of a difference pre/post turbo with one sensor.

Have you ever had a pre and a post at the same time on the same vehicle?

If not, try it, you might be surprised.

 

[mudgudgeon]

In which case you’d want 6… which is ideal

I don’t see too much of a difference pre/post turbo with one sensor.

Do some reading, hear and elsewhere.

EGT post turbo is done for convenience, pure and simple.

There's a large and non-linear difference in readings pre and post turbo.
If you're tuning so conservatively that the fúck up factor is no longer relevant, then install it post turbo. At which point it's a decoration on your dash.

 

[random101]

Have you ever had a pre and a post at the same time on the same vehicle?

If not, try it, you might be surprised.

I assume there would just be a delta that will vary

Do some reading, hear and elsewhere.

EGT post turbo is done for convenience, pure and simple.

There's a large and non-linear difference in readings pre and post turbo.
If you're tuning so conservatively that the fúck up factor is no longer relevant, then install it post turbo. At which point it's a decoration on your dash.

anyone have a good spot to install it on the manifold while I’ve got it out?

Happy to weld in a bung, I guess I’ll need to drill out a whole for the heat shield as well.

Anyone have any photos?

I’d expect some variation in the delta, as the turbo heat soaks and is cooled ect

But as you mentioned post turbo gives me a crude indication. Happy to relocate it…

 

[AussieHJCruza]

Post turbo is a waste of time. The generally accepted 'safe' post-turbo temperature in these parts is 550c. From running both, I can assure you that with a racy tune I ran for a very short time, especially at high load, low rpm situations where the wastegate is closed, I could easily get to 850c+ while the post-turbo reading was showing a reading that would be regarded as 'safe'

 

[DarkHorse1HDT]

I assume there would just be a delta that will vary

anyone have a good spot to install it on the manifold while I’ve got it out?

Happy to weld in a bung, I guess I’ll need to drill out a whole for the heat shield as well.

Anyone have any photos?

I’d expect some variation in the delta, as the turbo heat soaks and is cooled ect

But as you mentioned post turbo gives me a crude indication. Happy to relocate it…

Just above the turbo flange there's a good spot to drill and tap... and yes, needs a larger hole in the heat shield.

 

[random101]

View attachment 3317442

Just above the turbo flange there's a good spot to drill and tap... and yes, needs a larger hole in the heat shield.

No need to weld a bung in? Just tap the thread straight into the manifold?

 

[NRS91]

Just to add to the EGT discussion.
Cummins only provide post turbo spec to not exceed of 500c.
While it wont show the peak EGTs it shows how much heat is soaked into the valves, head and turbo so for cooling down after a run its ideal.

Its also the safest and easiest sensor install as its not risking manifold integrity or swarf into the turbo.

Just some info to add to the discussion.

 

[DarkHorse1HDT]

No need to weld a bung in? Just tap the thread straight into the manifold?

Yup, there's plenty of meat there.

Obviously remove the manifold to do it so you're not raining swarf into the turbo...

 

[AussieHJCruza]

Yup, there's plenty of meat there.

Obviously remove the manifold to do it so you're not raining swarf into the turbo...

Or do it slowly with a well-greased drill and tap and have the engine running as you break through.

 

[mudgudgeon]

No need to weld a bung in? Just tap the thread straight into the manifold?

Yes.

Have a look through my 105 series turbo install thread. Link in my signature line.

There's good photos of install location there. (EDIT - Page 2)

 

[mudgudgeon]

While it wont show the peak EGTs it shows how much heat is soaked into the valves, head and turbo so for cooling down after a run its ideal.

There's no direct relationship.
Cylinder head etc get cooled by oil, pistons get oil spray from underneath, and all of this gets a cool fresh intake charge every cycle.

 

[NRS91]

There's no direct relationship.
Cylinder head etc get cooled by oil, pistons get oil spray from underneath, and all of this gets a cool fresh intake charge every cycle.

True but residual heat in the engine and turbo will keep the EGTs higher once it's heat soaked so post turbo EGT is like an average temp and shows how hot everything is whereas pre turbo shows how hot the fire is.

I'll probably run both in my next build but my above comments come from Cummins engineers who are adamant than post turbo is the only way for engine longevity.

 

[mudgudgeon]

Cummins engineers who are adamant than post turbo is the only way for engine longevity.

Cummins engineers have commercial liability and asses to cover

 

[NRS91]

Cummins engineers have commercial liability and asses to cover

They were on the development side of things but yea the liability and longevity is precisely why I take their advice with decent weighting.

 

[mudgudgeon]

They were on the development side of things but yea the liability and longevity is precisely why I take their advice with decent weighting.

Toyota engines tune these engines extremely conservatively for the same reasons.
There's a lot left on the table.
There's long term evidence that factory tune is unnecessarily conservative.

There's also scientific literature on this stuff if you go digging.
There's loads of info in various places if you choose to dig for it.

Anyway, make your own judgement do what you're comfortable with.

 

[DarkHorse1HDT]

No need to weld a bung in? Just tap the thread straight into the manifold?

@mudgudgeon 's EGT install (post #39 if it doesn't take you straight there.)

Rolling the dice - slow moving turbo HZJ105 project

forum.ih8mud.com

I think I copied it for mine and it worked out well.

 

[random101]

Yup, there's plenty of meat there.

Obviously remove the manifold to do it so you're not raining swarf into the turbo...

I ended up doing it, not sure I’m 100% sure it won’t leak, not sure if I should use a copper washer to flatten it off?

 

[mudgudgeon]

I ended up doing it, not sure I’m 100% sure it won’t leak, not sure if I should use a copper washer to flatten it off?

View attachment 3351657

View attachment 3351658

Did it get tighter as you screwed it in to the manifold?
Most have a tapered thread, if it is a tapered thread they are self sealing

 

[random101]

Did it get tighter as you screwed it in to the manifold?
Most have a tapered thread, if it is a tapered thread they are self sealing

It did, but im not sure how far I went with the taper… should be okay I guess

 

[mudgudgeon]

It did, but im not sure how far I went with the taper… should be okay I guess

If it got tight before it bottomed out, it's probably good