Outer Limits 4x4 Board

Finally got around to fitting the EGT and Boost Gauge to the 1HZ w/ AXT turbo kit.

Boost is 5PSI @ 100km/hr
Max is 9.5psi (+/-0.5) at WOT

EGT sits on 450c at 100KM/Hr, 500 up small inclines.
620 seems to be normal max if you go flat throttle 0 - 120km/hr
I got it to 720 on a big hill on the way to gatton flogging all I could
Haven't tried the Twmba range yet.

No intercooler (yet)
All temps pre-turbo.
Exhaust is 2.5" Mandrel

My thoughts so far are
a) The turbo is too large. Although it drives just fine, I would like to see more boost earlier in the rev range and at cruise. It doesn't hit 10PSI until about 1800RPM. I haven't wound it to redline to test max flow yet. Might also play with the wastegate to see when it starts to crack open. This might give a bit more boost sooner.

b) If more boost means more air, and more air means lower EGT, how can you have too much boost? Would 14PSI be manageable

c) As it takes an absolute flogging to get anywhere near 720c - i think it could do with more fuel. How do I adjust this?

d) is 720c a fair figure for the 1HZ? It seems to be the number recommended here and there, but I would think it would vary somewhat for indirect injection vs direct injection etc.

e) Redline is 4200RPM, but there is nothing past 3000RPM. I know the n/a 1HZ 80 I used to drive onsite you had to flog with revs to get it anywhere. This one seems different, doesn't like revs, acceleration just falls off. Is there adjustment for rate of falloff at high RPM?

Thanx
Paul

I'll try and tackle this bit by bit.

me3@neuralfibre.com wrote: Boost is 5PSI @ 100km/hr
Max is 9.5psi (+/-0.5) at WOT

those are good, safe numbers.

EGT sits on 450c at 100KM/Hr, 500 up small inclines.
620 seems to be normal max
I got it to 720 on a big hill on the way to gatton flogging all I could
Haven't tried the Twmba range yet.

No intercooler (yet)
All temps pre-turbo.

that's all fine.

My thoughts so far are
a) The turbo is too large. Although it drives just fine, I would like to see more boost earlier in the rev range and at cruise. It doesn't hit 10PSI until about 1800RPM. I haven't wound it to redline to test max flow yet. Might also play with the wastegate to see when it starts to crack open. This might give a bit more boost sooner.

the turbo is correctly sized, however there are things you can do to make it come on sooner. that said, 1800 is not a bad rpm to get full boost, if the turbo was too big, it would be higher still. the best things you can do to help the boost come on at lower rpm are fit a freer flowing exhaust, and fit a boost controller; an electronic type is best however these http://cgi.ebay.com.au/Turbotech-manual ... dZViewItem are fantastic and provide remarkably good boost control.

Don't fiddle with the wastegate. just don't.

b) If more boost means more air, and more air means lower EGT, how can you have too much boost? Would 14PSI be manageable

more air means lower EGT only if the air is the same or lower temperature as the air you had before. more compression in the turbo means more heat in the air - hold your thumb over the end of a bike pump and pump it to see how hot air can when you compress it. more boost also means more load on the turbine side of the turbo, which is the equivalent of a greater exhaust restriction, which means more combustion heat is held in the engine. so on face value, more boost = lower EGT's, however it's not quite as simple as that.

c) As it takes an absolute flogging to get anywhere near 720c - i think it could do with more fuel. How do I adjust this?

it could maybe handle a LITTLE more fuel. but only a little. if your injectors are in good shape (ie less than 70,000km since fresh nozzles) then you could wind up the fuel a little bit. there is a screw on the top of the pump, facing the rear, turning it clockwise will increase the fuel. work in 1/16th turn increments, the screw is very sensitive. pick a good, long 3rd gear, full throttle hill where the engine will run at about 3000rpm for at least 1km for your testing. watch your EGT's very carefully and it's also good to have an observer (in a following vehicle or in your vehicle using a mirror) to watch for exhaust smoke. there should be no visible smoke.

d) is 720c a fair figure for the 1HZ? It seems to be the number recommended here and there, but I would think it would vary somewhat for indirect injection vs direct injection etc.

it's a good number. the occasional 750 pre turbo won't hurt it.

e) Redline is 4200RPM, but there is nothing past 3000RPM. I know the n/a 1HZ 80 I used to drive onsite you had to flog with revs to get it anywhere. This one seems different, doesn't like revs, acceleration just falls off. Is there adjustment for rate of falloff at high RPM?

there aren't really any DIY adjustments to the pump for that, however it is more likely due to exhaust restriction. possibly from insufficient fuel, your EGT numbers support a SLIGHT increase in fuel. do you notice the boost dropping off at higher RPM?

I wouldn't be hitting it with 14psi without intercooling; 11 is about the limit without cooling, the power gains above that tend to taper off a bit anyway.

hope that helps some.

cheers
DD

Exhaust is 2.5" mandel with straight through muffler.

Intake is std filter with factory snorkel.

Intercooler is TBA (to be advised) when I get the time to buy one from eBay, Justjap or a water to air.

I drove a Mike Vine intercooled 1HD-T 80 and it had a heap more torque down low. Was an absolute monster on the forst 1/4 throttle, toey as. Almost hard to drive. Unfortunatley top end was nowhere near as good. It would be good to get that "more toey" behaviour.

Paul

me3@neuralfibre.com wrote:Exhaust is 2.5" mandel with straight through muffler.

Intake is std filter with factory snorkel.

Intercooler is TBA (to be advised) when I get the time to buy one from eBay, Justjap or a water to air.

I drove a Mike Vine intercooled 1HD-T 80 and it had a heap more torque down low. Was an absolute monster on the forst 1/4 throttle, toey as. Almost hard to drive. Unfortunatley top end was nowhere near as good. It would be good to get that "more toey" behaviour.

Paul

I'd give it a whack without the snorkle. 1HD-T is famous for driveability even in standard form, but it does lac top end. if yours really feels flat off boost, it could probably do with a touch more fuel. without a boost compensator it's hard to get a good balance between smoke and go. more fuel without the boost compensator also means more soot in the oil.

Forgot to mention smoke

No smoke normal driving or flat throttle (WOT).
Moderate smoke if you flatten it in drive from idle till turbo get going. You'll leave a cloud, but it's not solid soot falling out like some trucks you see. Or a drag tractor...

Driveability is fine, just not the real toey feel this 1HD-T had. Was an auto but felt like a manual in 1st.

Paul

what would be safe egt's after the turbo, mine will hit 500 going up a steepish hill on the Hume holding it flat out, i think it would go over if the hill was longer.

also what are the signs the injector pump is tired and needs a re build?

full boost @ 1800 rpm sound pretty good .. 1HD-T factory settings make full boost ( aka 10 PSI ) at 2000 rpm ...

Your numbers sound pretty good IMOP .. you can make more boost in you add more fuel ( which cost more EGT ) and load .. with no load .. no boost ..

I just installed a turbo on my 1HZ, I have been adjusting fuel and boost to get varying results. If you turn the fuel down too low you will get higher EGT's and moderate boost, if you turn it too high you get smoke, tons of boost and high EGT's.

Too little fuel makes higher EGT's and it makes sense as a leaner fuel /air mix makes things hot. So turn up the fuel in quarter turn increments and the adjust slightly from there. Once you turn up the fuel your boost will come on quicker - you will like it.

Bottom line is you have to give it more fuel after a turbo install.

One other thing - does your truck have a high altitude compensator on the inject pump? Mine does and I think it messes with the fuel - i can only get abot 3400 RPM on it in 4th, can't get that high in 5th

dumbdunce wrote: fit a boost controller; an electronic type is best however these http://cgi.ebay.com.au/Turbotech-manual ... dZViewItem are fantastic and provide remarkably good boost control.

Don't fiddle with the wastegate. just don't.

Why do you say this?
I have had excellent results by cutting, threading and adjusting wastegate actuator rods and much prefer this to electronic boost controllers.
I can change boost from nothing to the max the engine/turbo combo is capable of.

lshobie wrote: Too little fuel makes higher EGT's and it makes sense as a leaner fuel /air mix makes things hot. So turn up the fuel in quarter turn increments and the adjust slightly from there. Once you turn up the fuel your boost will come on quicker - you will like it.

Bottom line is you have to give it more fuel after a turbo install.

This is more a symptom of your turbo being bigger than most. Most of the turbos fitted to diesels will make the usual 10psi or so without any additional fuel, so EGT's will drop markedly.

In your case the higher EGT's were necessary to spool up the turbo which in turn drops the EGT's. This isn't normally necessary.

geez, im gonna follow this thread closely

KiwiBacon wrote:

lshobie wrote: Too little fuel makes higher EGT's and it makes sense as a leaner fuel /air mix makes things hot. So turn up the fuel in quarter turn increments and the adjust slightly from there. Once you turn up the fuel your boost will come on quicker - you will like it.

Bottom line is you have to give it more fuel after a turbo install.

This is more a symptom of your turbo being bigger than most. Most of the turbos fitted to diesels will make the usual 10psi or so without any additional fuel, so EGT's will drop markedly.

In your case the higher EGT's were necessary to spool up the turbo which in turn drops the EGT's. This isn't normally necessary.

When I install my turbo ( K26.8 ) in my 2H ( factory NA ) I need to add plenty of more fuel to get boost .. ( 2.5 turns to the IP ) and before adding the turbo I reach easy 1200 F and climbing in a flat road .. ( means I get enough fuel prior turbo )

But don't think the K26.8 it's really to large for my engine ..

What do you think ...?

OK, I tried the little screw with a locknut on the back of the pump. Worked a treat. 3/16 of a turn gave wonderful driveability. Unfortunately it also gave plenty of off boost smoke. 1/16th is manageble.

The motor is 230 000km old and has had all factory services looking at the service handbook with previous owners. I doubt the injectors have been changed. Turbo was fitted at 6mths old ('98 model). It doesn't normally smoke (much) except for a puff off boost if you floor it. (as opposed to the cloud yesterday)

a) Would new injectors give significant off-boost smoke reduction, letting me wind it up again?

b) Where can I obtain a boost compensator that can be fitted to a 1HZ? (apart from paying a shop $1100+ to fit).

c) Are there any adjustments for high / low RPM fueling, or is that set firm with weights / springs?

With more testing yesterday my original numbers were out a bit.

350C at 100km/Hr Cruise
10PSI at 2200RPM
Boost falls off 2 PSI between 4200 and 4500RPM, presumably because engine is reducing fuelling.

Thanx
Paul

You have now found why it is necessary to fit a boost compensater. It gives you 3 independant adjustments to the fuel delivery.

Off boost smoke is either too much fuel being delivered or not enough air, we have found axt turbos to be on the larger size needed for these engines, other kit turbos work alot better down low.

Injectors may help, but not to the amounts your are wanting. Best to check all things that control air flow ie: air filter condition and valve clearances.

A boost comp is available to purchase seperately, but unless you know how to adjust them and have replaced a top cover on a pump before, I wouldnt recommend fitting it yourself. Thats why you ae paying 1100 ish. The pump is being removed, tested, set up so that you have a good idle speed, good fuel delivery and dont run the risk of running away if something goes wrong.

Andy

How much is a boost compensator?

lshobie wrote: Too little fuel makes higher EGT's and it makes sense as a leaner fuel /air mix makes things hot.

Sorry, you need to stick to petrol engines if that's what you think.

me3@neuralfibre.com wrote:
a) Would new injectors give significant off-boost smoke reduction, letting me wind it up again?

At 230k km, if they haven't been done they will absolutely need doing. (and although it's been serviced by the book, the book doesn't specify an interval on injectors). The pump should also be done for best results, and then you can turn it up. And then don't turn it up too far, it will go bang!

me3@neuralfibre.com wrote: b) Where can I obtain a boost compensator that can be fitted to a 1HZ? (apart from paying a shop $1100+ to fit).

Try calling some turbo fitters, or diesel injection shops that fit turbos, I don't believe the actual price of the part itself to be more than $500.

me3@neuralfibre.com wrote: c) Are there any adjustments for high / low RPM fueling, or is that set firm with weights / springs?

Nope, it's all fixed by the pumps internal specs, that's why you need the BC so the pump has some idea of the air mass going into the engine.

me3@neuralfibre.com wrote: Boost falls off 2 PSI between 4200 and 4500RPM, presumably because engine is reducing fuelling.

That will be the obvious reason, and it's true, however depending on the turbo sizing it could also be running out of puff.

You are getting max boost at perfect rpm range .. ( 1HD-T range ) and your temps looks pretty nice ..

You are getting more smoke than ..

http://www.youtube.com/watch?v=dtyD1kig ... ed&search=

KiwiBacon wrote:

dumbdunce wrote: fit a boost controller; an electronic type is best however these http://cgi.ebay.com.au/Turbotech-manual ... dZViewItem are fantastic and provide remarkably good boost control.

Don't fiddle with the wastegate. just don't.

Why do you say this?
I have had excellent results by cutting, threading and adjusting wastegate actuator rods and much prefer this to electronic boost controllers.
I can change boost from nothing to the max the engine/turbo combo is capable of.

in the past, I would have agreed wholeheartedly, and I have had good results doing exactly that. it does however require some (admittedly fairly basic) skills, a thorough understanding of what you are doing, and some tools that most backyarders won't have, and that will cost more than a boost controller to do once-off. Using a boost controller like the turbotech (I buy them in bulk now ) is faster, easier, and gives more precise boost control, with next to no wastgate creep below the set boost level and no flare or taper at the top end, why would you bother going to the trouble of making your actuator mechanically adjustable? easier to install, easier to adjust, better control, nothing to stuff up, the cost is less than the cost of the time to fiddle with the actuator, to me it's a no brainer.

of course for the bloke who loves to have a fiddle and isn't afraid of potentially destroying a $100ish wastegate actuator, and has the tools and skills, it's an option.

dumbdunce wrote:

KiwiBacon wrote:

dumbdunce wrote: fit a boost controller; an electronic type is best however these http://cgi.ebay.com.au/Turbotech-manual ... dZViewItem are fantastic and provide remarkably good boost control.

Don't fiddle with the wastegate. just don't.

Why do you say this?
I have had excellent results by cutting, threading and adjusting wastegate actuator rods and much prefer this to electronic boost controllers.
I can change boost from nothing to the max the engine/turbo combo is capable of.

in the past, I would have agreed wholeheartedly, and I have had good results doing exactly that. it does however require some (admittedly fairly basic) skills, a thorough understanding of what you are doing, and some tools that most backyarders won't have, and that will cost more than a boost controller to do once-off. Using a boost controller like the turbotech (I buy them in bulk now :D ) is faster, easier, and gives more precise boost control, with next to no wastgate creep below the set boost level and no flare or taper at the top end, why would you bother going to the trouble of making your actuator mechanically adjustable? easier to install, easier to adjust, better control, nothing to stuff up, the cost is less than the cost of the time to fiddle with the actuator, to me it's a no brainer.

of course for the bloke who loves to have a fiddle and isn't afraid of potentially destroying a $100ish wastegate actuator, and has the tools and skills, it's an option.

Slight hijack of my own thread, but I put a lot of thought into this over the years.

a) my wastegate has an adjustment thread on it anyway.

But on a broader scope. Although I have used bleeds and such previously, it seems silly to me to use a device to fool the input signal to the actuator. That's all a bleed is. The Turbotech one is a fixed pressure drop due tothe spring preload on the ball bearing.

A better solution would be this.

Assume actuator diaphragm area for arguments sake is 1sq inch. And you want to hold 10PSI of boost. Also assume that the stroke of the wastegate actuator is 1 inch from closed to fully open.
You need a spring in the actuator that has a rating of 1lb/inch. You then place it under 9.5" of preload. This means it will need 9.5psi on a 1sq inch diagram to crack it. at 10.5psi it will be fully open. Interestingly enough adjusting the rod adjusts the pre-load on the spring. Provided the spring rate is close to correct, creep will be minimal, as it won't start to open until the pre-load is exceeded. I think people get confused as they forget to factor in pre-load.

I think (and haven't tested yet) a simpler and more effective solution than bleed systems would be an additional external spring. It only needs to be very low rate, and quite long. Simply pre-load it to the additional PSI you want x the diaphragm area - presto - additional boost added.

The problem I see with the Turbotech device is not the fixed pressure drop, that's fine, it's the release. As the valve they are using is also a one way valve, they have to dump the air when manifold pressure drops. They do this through a fixed diameter orifice, a rather crude solution, as the device then becomes a mixture of a bleed (flow based) and fixed pressure drop, giving flow based rate changes. A fix would be a second one way valve that retuned the air to the manifold as the relative pressure fell. Otherwise the rates of waste gate closing are a bit vague.

The comments that circulate about creep seem to be generally a bit vague in their information (I'm an old fast fours boy). I know it happens, dropping the wastegate actuator pipe will show how much it is happening on that particular vehicle. The correct solution is preload and spring rate. If you can't screw with the factory one (they are sealed), then simply add an external.

Paul

you've thought about this a lot, I see.

me3@neuralfibre.com wrote: Assume actuator diaphragm area for arguments sake is 1sq inch. And you want to hold 10PSI of boost. Also assume that the stroke of the wastegate actuator is 1 inch from closed to fully open.
You need a spring in the actuator that has a rating of 1lb/inch. You then place it under 9.5" of preload. This means it will need 9.5psi on a 1sq inch diagram to crack it. at 10.5psi it will be fully open. Interestingly enough adjusting the rod adjusts the pre-load on the spring. Provided the spring rate is close to correct, creep will be minimal, as it won't start to open until the pre-load is exceeded. I think people get confused as they forget to factor in pre-load.

you also need to factor in the loads generated on the wastegate itself by the exhaust flow; under most conditions, the exhaust pressure will tend to hold the wategate open, under others the load may be more balanced.

there are also two kinds of preload on your wastegate actuator spring, let's call them internal and external - the internal preload is the amount the spring is compressed when the actuator is removed from the wastegate arm, external is the preload that actually holds the wastegate valve hard against its seat. the pressure on the diaphragm works to overcome BOTH types of preload, and as soon as there is ANY positive pressure on the diaphragm, the preload is effectively reduced, which may allow the wastegate to come off its seat, with the assistance of the exhaust pressure. if you do not have a boost controller, this will ALWAYS happen. This is wastegate creep. it is unavoidable without a boost controller. it is also unavoidable with a bleed type boost controller, although it is much masked.

I think (and haven't tested yet) a simpler and more effective solution than bleed systems would be an additional external spring. It only needs to be very low rate, and quite long. Simply pre-load it to the additional PSI you want x the diaphragm area - presto - additional boost added.

it will work the same as adjusting the actuator arm or spacing the actuator with washers etc.

The problem I see with the Turbotech device is not the fixed pressure drop, that's fine, it's the release. As the valve they are using is also a one way valve, they have to dump the air when manifold pressure drops. They do this through a fixed diameter orifice, a rather crude solution, as the device then becomes a mixture of a bleed (flow based) and fixed pressure drop, giving flow based rate changes. A fix would be a second one way valve that retuned the air to the manifold as the relative pressure fell. Otherwise the rates of waste gate closing are a bit vague.

I had the same fear when I first bought a turbotech and pulled it apart to see how it worked; I think the bottom line is the volume in the actuator is very small and bleeds out very quickly, and the spring in the actuator is also quite strong, so as boost drops, the valve shuts very quickly. consider that the hole in the end of the wastegate where the air gets in is only about 3/16", the flow back out of there is already somewhat attenuated. I'm confident that if I went and put an actuator in the vice and activated it with compressed air at 15psi, I would not be able to discern the difference in closing times with or without a turbotech plugged in.

anecdotally, my 80 (multivalve factory turbo running 15psi), on a 3000rpm gearchange the boost drops to about 6psi in the time it takes to change gears, and builds quickly from there. it builds boost from idle and from mid throttle faster than factory, I can't see any way in which the closing rate of the valve has been negatively effected.

The comments that circulate about creep seem to be generally a bit vague in their information (I'm an old fast fours boy). I know it happens, dropping the wastegate actuator pipe will show how much it is happening on that particular vehicle. The correct solution is preload and spring rate. If you can't screw with the factory one (they are sealed), then simply add an external.

Paul

I hope I have explained wategate creep up there^ ? wastegate creep causes boost to build more slowly than it would if a device were employed to hold the wategate fully shut until a predetermined manifold pressure is reached. it always happens whenever a boost controller is not employed.

there is also boost creep which can also be called flare or taper, where at the top end, boost creeps up (flares) or tapers (drops off). flare is often due to an undersized wastegate, however can happen when the correct sized wastegate is used with too much external preload, limiting the effective stroke of the actuator.

taper most commonly occurs in diesels due to ramping down of fuel delivery at the top of the rpm range; there are several other reasons why this might happen however I don't think they apply in this situation - inlet or exhaust restriction, undersize turbo bypassing/going supersonic, insufficent fuel etc.

is this of any help?
cheers

Brian

Threads like this is why I love this forum ... informed and intelligent thought.

love_mud wrote:Threads like this is why I love this forum ... informed and intelligent thought.

we could all be just spouting poo though, that's why I love this forum - everyone is an instant expert heh heh halerus

dumbdunce wrote:

love_mud wrote:Threads like this is why I love this forum ... informed and intelligent thought.

we could all be just spouting poo though, that's why I love this forum - everyone is an instant expert heh heh halerus

Thats true .. but multiple people would have to be spoutingh similar poo ... and I wold have to be to stupid to not see that not only do the answers make sense .. bit so do the explaniations that abck em up ..



Pls excuse poor typing\grammar .. grog affected fingers ...

Any idae how much a boost compensator costs for a 1HZ - I've been asking around but can't find a price.

Thanks

Any idae how much a boost compensator costs for a 1HZ - I've been asking around but can't find a price.

Thanks

i dont think you can... the boost compensator is a part of the newer 1hz injector pumps

??

Hmm, the older 1HDT injector pumps have a boost comp on them -- they should be able to swap top sections I am pretty sure. The new ones I have no idea - other than the new iHZ's dont have a boost comp as they dont have a turbo.

lshobie wrote:Any idae how much a boost compensator costs for a 1HZ - I've been asking around but can't find a price.

Thanks

srcoll up dude, Andy has answered your question and would be happy for your business.