Thread: VNT Turbo Setup??

Originally Posted by mike_ie

Yeah, ideally I'd like to add a lip to the end of each pipe, but don't have the means to do so.

Welder, low current setting, add a bead around the pipe end. Failing that swage the pipe a little using the pointy end of an anvil, or even a closely adjusted small shifting spanner. File the sharp edges that result and you'll be fine.

You don't have enough fuel available for damaging egt's, I was going to Russia in mine prior to making babies

Are you doing the clamps up tight enough, sounds like they are to loose?

Originally Posted by bee utey

Welder, low current setting, add a bead around the pipe end. Failing that swage the pipe a little using the pointy end of an anvil, or even a closely adjusted small shifting spanner. File the sharp edges that result and you'll be fine.

If it holds together for now, it's going on the "things to do when I get home" list :-D I have access to industrial pipe flaring machinery there. Thought about welding a bead round it, but my welding ain't pretty...

Originally Posted by rovercare

You don't have enough fuel available for damaging egt's, I was going to Russia in mine prior to making babies

Are you doing the clamps up tight enough, sounds like they are to loose?

Clamps are all good, and everything seems good now. So, you're saying to wind out the fuel screw some more? :-D

Just had a quick surf looking for other dodgy solutions to pipes blowing off.
A simple one that popped up a few times was just to add 4 small beads/spots of weld at 3,6,9,12 o'clock positions. Supposedly enough to stop hoses blowing off but easier to achieve than welding a full bead.

Steve

Originally Posted by mike_ie

Yeah, was thinking the same thing yesterday when it went pop. Losing all power in a sticky situation certainly a concern of mine.

Yeah, ideally I'd like to add a lip to the end of each pipe, but don't have the means to do so. At the moment a big part of the problem is that the oil I lost through the turbo last week has worked its way into every joint, lubricating them in the process. Everything got a cleandown last night, including the intercooler.

In my experience swaged pipes just make everything awkward to get on and off. Bolt on straps (tig a threaded stub onto each pipe, also serves as a locator for the joiners/boots) are so nice and easy to get on/off and positively locate the pipes too.

Even with good clamps and no straps it's marginal enough that a bit of oil on the sleeve and it'll never stay. If you ever need to do a repair in the dark of night somewhere, there will be oil all over the joints and they won't stay.

With straps the BS stops, forever. Consider putting them on in the future.

Originally Posted by mike_ie

With the VNT vanes fully closed (vacuum actuator on full vacuum), I'm getting 20psi uphill and about 450°C. What values should I be aiming for? Bearing in mind that this will be used for travel, not a weekend hill climbing competition rig

The factory turbo pumps can put out about 140cc/1000 shots. But I'm not convinced the non turbo pumps deliver the same amount.
If you can max out a turbo fuel pump then you will need 25psi boost at 2000rpm ramping up to 33psi at 3,200rpm.

This will burn the 140cc/1000 shots cleanly and deliver peak torque of ~750Nm (consevative figure) at approx 2,100rpm leading to power of ~216kw at approx 3,200rpm.

You'll need a turbo capable of delivering ~35lb/min of air at a PR of around 3.5.
You'll need an intercooler capable of shedding 28kW of heat and keeping outlet temps around 90C. Temp into the intercooler, around 200C.

With 450C at 20psi you have a long way to go. 650C is as conservative as you ever need to be.

Might have to do something about my pipework after all - pretty much had the overtaking-*POP* experience on a highway run earlier. To be fair though I had the fuel screw wound out a bit too much, so it was popping at the 30PSI mark. Wound her back a bit, and everything is holding together.

Thoughts so far... hard to say really. Turbo is kicking in fine, getting a bit of vibration in the drivetrain at speed, not sure what thats about, and for some reason 5th gear seems like it could be a bit taller than it is?? It's hard to describe, as I haven't driven many Isuzu powered Land Rovers so far.

On a separate note, is the 4BD1 power steering pump more powerful or at a higher pressure than the 300tdi equivalent? Steering is as light as a feather by comparison....

Having been driving both a County and a Disco lately, I feel the steering in the County is lighter as well Mike. I've wondered if it's because the steering wheel in the County is quite a lot larger, so it feels easier....