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4.2 Injector pump for Big HP

Tech Talk for Nissan owners.

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Re: 4.2 Injector pump for Big HP

Post by SuperiorEngineering »

Duramax is not an option for us, i was talking to one of our customers who came out today with his GU , it has a Duramax fitted that cost around the 24K for the engine,box, exhaust, and conversion costs, i am told its upwards of 40k for what he has now , thats way over what i need to spend for what we are trying to achieve.
Although it would be a better long term option.
Mick
Last edited by SuperiorEngineering on Tue May 10, 2011 6:03 pm, edited 1 time in total.
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Re: 4.2 Injector pump for Big HP

Post by OUTLAW565 »

24k for a duramax conversion is ludacris...I can have a duramax and alison landed at my door for under 10k.
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Re: 4.2 Injector pump for Big HP

Post by SuperiorEngineering »

OUTLAW565 wrote:24k for a duramax conversion is ludacris...I can have a duramax and alison landed at my door for under 10k.
yes i certainly was shocked when he said 24k , i am under the impression that was everthing done drive in drive out.
as for the 40 k he stated that is what the guy would estimate he would charge for the same if done now, i cant imagine too many guys would be lining up for that.
any way it is about td4.2 not duramax.
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Re: 4.2 Injector pump for Big HP

Post by vanbox »

I have a duramax and can say the above is part fact and fiction.

I love my motor, but gee this is fascinating reading! As Mick said, its not about what may be the most practical (duramax, LS2 etc) but what can a td do.

I hope this thread doesnt get lost in outers history, I love it!

I wish I had the time/coin to put a duramax in a coopers style race. To get up against these td's you are building.

I have known Kev for a while now and look forward to seeing the outcome!

Ill be spectating more of these styles of racing for sure

cheers

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Re: 4.2 Injector pump for Big HP

Post by 1MadEngineer »

SuperiorEngineering wrote:
OUTLAW565 wrote:24k for a duramax conversion is ludacris...I can have a duramax and alison landed at my door for under 10k.
yes i certainly was shocked when he said 24k , i am under the impression that was everthing done drive in drive out.
as for the 40 k he stated that is what the guy would estimate he would charge for the same if done now, i cant imagine too many guys would be lining up for that.
any way it is about td4.2 not duramax.
mick
I would have thought that the 300+kw TD42 will be every bit of $15k+ once completed, and even then as everyone has stated 'it will be on the ragged edge'. Seems like a lot of false economy to me :? sure it may be $5-7k dearer, but it will make that power (and a HEAP MORE) day in day out, rather than hanging on to the pin of a hand grenade.

If you are just chasing a cheap ass - mega flow pump setup, then run twin pumps! Its easy as to do, and a pressure compensated flow control can bleed off extra flow until demand is needed on the 2nd pump ;)

Otherwise, maybe its time to change to a petrol engine?
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Re: 4.2 Injector pump for Big HP

Post by Mosko111 »

1MadEngineer wrote:
SuperiorEngineering wrote:
OUTLAW565 wrote:24k for a duramax conversion is ludacris...I can have a duramax and alison landed at my door for under 10k.
yes i certainly was shocked when he said 24k , i am under the impression that was everthing done drive in drive out.
as for the 40 k he stated that is what the guy would estimate he would charge for the same if done now, i cant imagine too many guys would be lining up for that.
any way it is about td4.2 not duramax.
mick
I would have thought that the 300+kw TD42 will be every bit of $15k+ once completed, and even then as everyone has stated 'it will be on the ragged edge'. Seems like a lot of false economy to me :? sure it may be $5-7k dearer, but it will make that power (and a HEAP MORE) day in day out, rather than hanging on to the pin of a hand grenade.

If you are just chasing a cheap ass - mega flow pump setup, then run twin pumps! Its easy as to do, and a pressure compensated flow control can bleed off extra flow until demand is needed on the 2nd pump ;)

Otherwise, maybe its time to change to a petrol engine?
Mate i think you will find that some buiseness can set up a td42 for a fair few grand cheaper then your guessed cost.
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Re: 4.2 Injector pump for Big HP

Post by sswaffie »

Duramax would be a great option but i believe the boys are looking at doing
CAMS events aswell and this will be out side cams regulations

4.5 Turbo diesel and 3.5 turbo petrol is all you are aloud for cams or
7.3 NA diesel (yawn) and 6l Na Petrol

I dont believe They are as highly strung if done properly with the correct
amount of boost and a efficient intercooler . The internals are huge !

And mosko Mad engineer is close to the money to achieve the 300+ range
Do some sums , it adds up quite quickly

On another note Has anyone priced Replacment injectors for the Duramaxes?
I believe they are close to the Grand each mark! even maby a bit more

Not taking anything away from the Duramax but they are expensive to repair
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Re: 4.2 Injector pump for Big HP

Post by Northside 4x4 »

Thanks for all the info Kiwi and Dieslex, I do appreciate both of you taking the time to argue out a point from multiple perspectives.
I believe when people are talking about breaking HP barriers etc.. Every bit helps, and that is what I was trying to convey. I will leave it at that for now though so its not an endless back and forth on the same subject.

It will be good to see how the real world figures measure up to the data and calcs, So if anyone has a car with a W-M/I system on that doesnt mind some dyno time let me know and I will happily arrange a data collection afternoon so we can share results and compare to the theoretical data.

I would consider $15K to be a generally good estimate for the amount of work needed for 300+hp
List of Work to be carried out and conservative pricing on it.
Full engine rebuild basically (Remove, Disassemble, Machining, Balancing, Reassembly, refitting etc..) $5-6K
Head Porting $600
Internal Coatings $900
Injector Pump $1500
Turbo $1800
Labour to fit turbo and Inj Pump Inc braided lines, timing, tuning etc.. $750
Recon Injectors $300
Intake and airbox $600
Fabricate Exhaust Manifold & New Dump pipe $800
Intercooler & Inlet manifold $2K+
*this is not a quote, its an estimate value of the parts*

Sure you would have some sponsor discounts etc.. but I think it would still be pushing over 10K minimum.
Thats if nothing breaks to, if something internally lets go on the first round...
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Re: 4.2 Injector pump for Big HP

Post by uzdnabuzd »

Bigger radiator and clutch also...........another 2k
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Re: 4.2 Injector pump for Big HP

Post by moddedgu »

sswaffie wrote:Duramax would be a great option but i believe the boys are looking at doing
CAMS events aswell and this will be out side cams regulations

4.5 Turbo diesel and 3.5 turbo petrol is all you are aloud for cams or
7.3 NA diesel (yawn) and 6l Na Petrol

I dont believe They are as highly strung if done properly with the correct
amount of boost and a efficient intercooler . The internals are huge !

And mosko Mad engineer is close to the money to achieve the 300+ range
Do some sums , it adds up quite quickly

On another note Has anyone priced Replacment injectors for the Duramaxes?
I believe they are close to the Grand each mark! even maby a bit more

Not taking anything away from the Duramax but they are expensive to repair
Shawn You talk about an efficient Intercooler setup! Care to elaborate a bit more on what fits into this category in your view? Also I'm assuming efficiency is determined by intake temperature reduction!

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Re: 4.2 Injector pump for Big HP

Post by sswaffie »

Good cyl head porting will cost close to $300 / cyl
On a cast iron head . You will pay $200/cyl for a alloy head
And man your fuel pump is cheap ! I might have to get you
To do my pumps at that cost!
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Re: 4.2 Injector pump for Big HP

Post by SuperiorEngineering »

All that taken in about duramax , if Myself and kev wanted to change motors we would opt for a a 6 litre blown or twin turbo'd engine for a lot cheaper than a duramax and that is not what we are after, it is about what can be supplied for a TD42 and who can and has made really good usable HP in race applications.

So far by the posts there are a few guys in aus and abroad who have the skills and knowledge to do such a job, something at the start of the post many thought was impossible.
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Re: 4.2 Injector pump for Big HP

Post by Northside 4x4 »

Yep, lots of stuff I have missed as uzdnabuzd has mentioned.

$15K starting to seem like not a bad price already.
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Re: 4.2 Injector pump for Big HP

Post by Northside 4x4 »

sswaffie wrote:Good cyl head porting will cost close to $300 / cyl
On a cast iron head . You will pay $200/cyl for a alloy head
And man your fuel pump is cheap ! I might have to get you
To do my pumps at that cost!
:D I know what they are all worth, but as I said Conservative pricing as Im not here to try and quote on the parts, just give people an indication of how quickly all the bits add up, even if they are priced below trade.
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Re: 4.2 Injector pump for Big HP

Post by peter ayers »

Love the reading guys... My Landcrusier ute ( On & off road mechanical ) has 265hwhp running 23 psi. I raced Shawn in the finals of the hill drags the last two years at expo. Anyone who was there would know how fast that thing of shawns is. I felt like i was standing still when we hit 3rd gear. The year before both of our utes were very close. I think it was 0.01 of a second was between the cars. This year he beat me by over a second!!! I know how much time Shawn has spent on R & D and the results speak for themselves. Congrats on the product you have developed!!!

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Re: 4.2 Injector pump for Big HP

Post by sswaffie »

In reply to intercooler , even though off topic a bit

A good FMIC with good tanks for flow, dumb , simple and works well!
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Re: 4.2 Injector pump for Big HP

Post by Dzltec »

What is Coopers style racing? Why such a high hp, does it require high speed 100% throttle? Im sure all the bolt ons will help, but don't think std internals will cut it for the long term. I think 15k would be a minimum in cost.

As for w/m working, it allowed my 1hdt to gain 30rwkw on a 50/50 mix. Yes it worked well, will be going on my own td42 once rebuilt. It works well as an on/off source of power.

Can someone also explain how they derive the fuel delivery specs for the power. The test plans for the pumps and power outputs they make are a lot different to what is written. ie td42 makes 50cc per 1000 shots at 2000 engine revs. This makes 50-55rwkw. A td42t does 65-70cc from memory and makes 70-80rwkw. I will have to check actual test plans tomorrow to double check.

So how does 150cc make 200rwkw? Assuming there is 30-40kw driveline loss?

Good luck on your endeavours, I think it will be wise to deal with someone nearby ish to sort out the niggles.

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Re: 4.2 Injector pump for Big HP

Post by digsy »

Where has everyone been reading that "as people have been saying they will be highly strung"?? - in referance to Shawn Swaffields motor.
I don't believe his TD4.2's are any more "strung" than any other higher HP motor out there.
Shawn has been racing his now for atleast 2 years in heaps of events (atleast 6 per year) and every event it is double nominated with his Co-Dawg! That's alot of competition miles under it's belt to go around saying that it's "highly strung"...

What WAS said was that it runs some higher EGTs but he monitors that on high speed straights and uses that thing between his ears to control the right foot - this is simply smart racing as the added HP out of corners etc in Coopers Rally is worth the trade off. Again I don't think this makes it "highly strung" just a smart racer...

I reference Shawn directly because it is obviously his car that we are talking about on here at the moment (the rumours definately are a buzz about what it does and doesn't have HP wise... who is worried about a number - check out the way that crazy arse GQ goes.... :shock: )

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Re: 4.2 Injector pump for Big HP

Post by Josh n Kat »

welll that's a good point Digsy, sure in a perfect world you'd set it up so you could hold it flat stick and the thing would never heat up but even in the top level of racing in V8 supercars and F1, they still have overheating issues and work with the car instead of pushing it too hard.

Sorry for the highjack.

Back to the horsepower hunt :popcorn:
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Re: 4.2 Injector pump for Big HP

Post by KiwiBacon »

Josh n Kat wrote:welll that's a good point Digsy, sure in a perfect world you'd set it up so you could hold it flat stick and the thing would never heat up but even in the top level of racing in V8 supercars and F1, they still have overheating issues and work with the car instead of pushing it too hard.
Overheating water and overheating EGT's are quite different things.
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Re: 4.2 Injector pump for Big HP

Post by Josh n Kat »

Yeah for sure kiwi i realise that, was more just reinforcing the point that with a switched on driver, EGT's can be "controlled" to a degree.

What's the best way to get better control of skyrocketting EGT's?
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Re: 4.2 Injector pump for Big HP

Post by CustomTurbos »

Josh n Kat wrote:Yeah for sure kiwi i realise that, was more just reinforcing the point that with a switched on driver, EGT's can be "controlled" to a degree.

What's the best way to get better control of skyrocketting EGT's?

Well the answer is easy to say but harder to do:

"design it right in the beginning"

Ugotnufen might remember what the fixed rpm 3500, 292rwhp on 35" did egt wise when using vnt. That was sustained from ~ 250-292 rwhp for 10 seconds or so. I couldn't see the gauge from where I was standing - he dynoed it. I know the retarder got so hot it needed a break!

EDIT

I just remebered a critical point. When we tried my vnt on the TD42, this was an engine that was 100% stock, never opened from Nissan. Not balanced, nothing (except 4 core laminova).

On top of that, the engine had injested alot of muddy water and the mud in it... to the point that the turbo was buggered and later the engine was pulled apart to find stuffed valve seats etc.

It was during this build that the work was done on the head all the coatings, balance etc.

So what I am saying is, you can save alot of dough by selling your working TD42 and buy a long block from Nissan. Maybe change valve springs to RB30E..... You can get 95% of the peformance and save probably $3K at least. The only caveat I would make is that it *might* be worth opening it up and hone out the liners for a bit more clearance. While your there balance pistons and rods and clean up behind valves and mild port match ONLY. Keep it really simple.

Then go for a well sized turbo and well thought out front mount and well designed fuel ramp of pump to match the "system" you have created.

If you can get 330whp doing all the other stuff, I bet you can get the same peak torque and over 300whp just doing the above.

And furthmore......the 292whp was by no means any limit we found. In fact at the time the numbers were a bit high. If we re-visted it, I have no doubt at all on a dead stock engine with 165cc at 3800rpm I (EDITE "we") could get 330whp without need to lift throttle.

To prove it, I may do it on a 1HZ (with 1HZT pistons/rods) just for kicks! Need to find someone interested in Perth to trial it though and spend the money on stuff other than turbo and controller.......
Last edited by CustomTurbos on Wed May 11, 2011 1:27 pm, edited 1 time in total.
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Re: 4.2 Injector pump for Big HP

Post by KiwiBacon »

Josh n Kat wrote:Yeah for sure kiwi i realise that, was more just reinforcing the point that with a switched on driver, EGT's can be "controlled" to a degree.

What's the best way to get better control of skyrocketting EGT's?
Short story is more boost. Long storey is Graeme's post above, design everything to work together, including more boost.
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Re: 4.2 Injector pump for Big HP

Post by CustomTurbos »

Dzltec wrote:ie td42 makes 50cc per 1000 shots at 2000 engine revs. This makes 50-55rwkw. A td42t does 65-70cc from memory and makes 70-80rwkw. I will have to check actual test plans tomorrow to double check.

So how does 150cc make 200rwkw? Assuming there is 30-40kw driveline loss?

Andy

Three main reason Andy;

the first is that there is a fixed and variable loss on the dyno. Not considering this is why when people get 50% more at the wheels they think they have 50% more at the engine - not true.

the second is that boost with turbo is not free entirely (typically 1/3 of belt driven SC) and when the wastegate opens it costs even more nm's as the revs rise. The earlier the wastegate opens as a % of the operating rpm range, the more power is wasted. This is in the form of worsening EMP vs IMP as revs rise. I never chjecked it, but experience tells me that the vnt would have been around 1:1 and may if we were lucky have been better than 1:1 ie: EMP is actually lower than IMP. This lower ratio improves scavenging dramatically and improves the resulting AFR (due to better VE) for a given boost.

The 3rd reason is that as the BMEP increases in a turbo vs NA engine and AFR and timing are optimised, the BSFC improves because once again there are fixed and variable components to the losses in an engine. However, with 15 or so to 1 AFR, the engines are not efficent and in fact a petrol engine is more efficient by a fair margin so these increases in BMEP are not reflected in an improvement in BSFC, rather the reverse is true
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Re: 4.2 Injector pump for Big HP

Post by CustomTurbos »

KiwiBacon wrote:
Josh n Kat wrote:Yeah for sure kiwi i realise that, was more just reinforcing the point that with a switched on driver, EGT's can be "controlled" to a degree.

What's the best way to get better control of skyrocketting EGT's?
Short story is more boost. Long storey is Graeme's post above, design everything to work together, including more boost.

And when Dougal says more boost, he is making an assumption that people will design the system so that the turbo is well macthed to the engine. ie: EMP:IMP isnt 4:1.....
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Re: 4.2 Injector pump for Big HP

Post by Josh n Kat »

Ah i see.

I was just thinking with a 45psi boost figure the intake air temps would be huge but with a well set up intercooler that is no longer a major factor.
So the unburnt fuel from lower boost then begin causing EGT's up?
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Re: 4.2 Injector pump for Big HP

Post by CustomTurbos »

Josh n Kat wrote:Ah i see.

I was just thinking with a 45psi boost figure the intake air temps would be huge but with a well set up intercooler that is no longer a major factor.
So the unburnt fuel from lower boost then begin causing EGT's up?
EDIT to make a bit clearer. Often when I write I think the readers know what I am thinking - my Wife does this alot (as in thinks I know what she is thinking.....)


Not exactly, no.

For a fixed fuel load/flow, lowering the AFR means there is less air to heat up during combustion. Almost all the fuel burns (ie: is broken down) but not to completion since the reaction has favourite steps and there is not enough AVAILABLE (while it may be above stoichiometric, not enough O can get to the C and to a much lesser extent H, fast enough. H isnt so much a problem because being the smallest atom, it is highly mobile. This is reaction rate kinetcs) oygen present to fully oxidise the fuel. In the absence of freely available oxygen, the more favourable reactions are....favoured.

The first is the creation of the O-H bond (to make H-O-H), this necessitaes the split of the H-C long chain molecule. So, even in very low AFR, you will get H2O forming and alot of soot. But the soot has alot of energy in it too. The next most favourable is C=O which is carbon monoxide and the next is CO + O to O-C-O. This has far less energy but still worthwhile.

Remember a gas has mass therefore needs energy to heat it up, if for example on a 16:1 AFR there is 90% of the available energy (ie: same fuel load, but making alot of CO and C so not 100% of available energy is converted to heat) but 70% of the amount of mass to heat up (compared to 23:1), the temps are going to increase.

A given amount of energy heating a lower mass = less BMEP than heating a higher mass (EDIT: If infinite:1 compression ratio in closed heat system, it is the same), so BSFC drops, also higher temps mean a higher rate of heat transfer into the combustion area, so more is lost to the radiator.

And also very importantly, for a fixed IMP, the higher your EMP is then the higher the pre turbo temp will be.
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Re: 4.2 Injector pump for Big HP

Post by marty »

Dieslex wrote:
Josh n Kat wrote:Ah i see.

I was just thinking with a 45psi boost figure the intake air temps would be huge but with a well set up intercooler that is no longer a major factor.
So the unburnt fuel from lower boost then begin causing EGT's up?
EDIT to make a bit clearer. Often when I write I think the readers know what I am thinking - my Wife does this alot (as in thinks I know what she is thinking.....)


Not exactly, no.

For a fixed fuel load/flow, lowering the AFR means there is less air to heat up during combustion. Almost all the fuel burns (ie: is broken down) but not to completion since the reaction has favourite steps and there is not enough AVAILABLE (while it may be above stoichiometric, not enough O can get to the C and to a much lesser extent H, fast enough. H isnt so much a problem because being the smallest atom, it is highly mobile. This is reaction rate kinetcs) oygen present to fully oxidise the fuel. In the absence of freely available oxygen, the more favourable reactions are....favoured.

The first is the creation of the O-H bond (to make H-O-H), this necessitaes the split of the H-C long chain molecule. So, even in very low AFR, you will get H2O forming and alot of soot. But the soot has alot of energy in it too. The next most favourable is C=O which is carbon monoxide and the next is CO + O to O-C-O. This has far less energy but still worthwhile.

Remember a gas has mass therefore needs energy to heat it up, if for example on a 16:1 AFR there is 90% of the available energy (ie: same fuel load, but making alot of CO and C so not 100% of available energy is converted to heat) but 70% of the amount of mass to heat up (compared to 23:1), the temps are going to increase.

A given amount of energy heating a lower mass = less BMEP than heating a higher mass (EDIT: If infinite:1 compression ratio in closed heat system, it is the same), so BSFC drops, also higher temps mean a higher rate of heat transfer into the combustion area, so more is lost to the radiator.

And also very importantly, for a fixed IMP, the higher your EMP is then the higher the pre turbo temp will be.
My brain is hurting a little.
So are you saying that although the afr is low e.g 16:1, that that doesn't automatically mean excessive egt's? Putting it simply.

Marty
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Re: 4.2 Injector pump for Big HP

Post by KiwiBacon »

marty wrote:My brain is hurting a little.
So are you saying that although the afr is low e.g 16:1, that that doesn't automatically mean excessive egt's? Putting it simply.

Marty
Graeme's translater here. :armsup:

Basically there are two problems with running a diesel very rich, the first is not burning the fuel enough to release the heat it should, which in a little way doesn't increase the EGT's as much as you might expect. The second is not enough air packed in, which can be heated to a higher temp than more air will, this always increases EGT's.

So you get richer and richer it gets hotter and hotter. But eventually you can reach a point where you're injecting soo much fuel that very little burns and temps will drop again. Kind of like a petrol engine, but it'll look like a snow-blower that's just eaten a ton of coal. Just like all those videos of redneck tunes on youtube. :roll:
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Re: 4.2 Injector pump for Big HP

Post by sswaffie »

[quote="Dieslex1 EMP is actually lower than IMP. This lower ratio improves scavenging dramatically and improves the resulting AFR (due to better VE) for a given boost. [/quote]


Can you tell us what you mean by scavenge ,are you refering to valve overlap scavenge ?


We are running a ratio of 1:1 EMP vs IMP A little higher while producing the boost (not much) but once boost is made its 1:1

The therory of leaning AFR to produce more HP (Increse boost and not touch fuel) Spot on the money there!

The problem that we are facing ATM is Boost and to make intercooler efficienty better ,Its hard to get a non VNT to create high boost , be in its efficienty range and spool decient enough its not a pig under 2200 rpm.
Answer - Vnt or compound turbochargers

The problem is making it cost effictive to the customer , fair enough if thats what they want and they are willing to spend the money but its very rare people want to spend 15 k on a td42 as it is. so people still need to keep in mind what is cost effictive for target HP .
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