Why would high egt's crack a block?

Look at all the motors running 250bhp plus.

How many crack a head and block after minimal miles under 15k modified i believe?

I haven't heard of one.

Whats different about this one?

Its running stock injectors on a jabbasport 'secret' map as they don't want people to know how they can push more bhp than everyone else on standard injectors.

I have 2 friends who are running 280bhp or thereabouts on pd130 engines with a lot over 100k miles, both are running uprated injectors and have no issues.

How can a 40k mile engine crack.....

How is it different to every other high bhp engine??

The answer is the injectors / map.

EGTs on mine are within tolerances but then I have had the head breathed on and run large injectors so I guess this means the engine is not stressed in terms of pressure when being asked to supply 300 horses.

 

I love my EGT gauge because it tells me exactly when I may need to back off on a trackday, even if the car still feels like it is giving plenty,  

Running dangerous injection period on the standard injectors at crazy bhp levels.

All good for a few miles but ends in tears

 

You've mentioned this a few time Jase but I am curious how a longer injection period, which is essentially (in my understanding) still injecting fuel as the piston moves down when there is less compression going to lead to cracking a block.

 

I feel that you are adding 2 and 2 and coming up with an answer as the "secret" map is the only link.

But that doesn't really mean that it's actually the reason.

 

You have not seen the injection cycles, map, etc...

 

Admittedly it's not unusual for you to have an opinion though.

A cracked block (to my knowledge) only comes from things getting too hot.   How it gets too hot and what breaks to cause the cracking (eg, broken rod thrown through the side) can be discussed lots as there's lot of possibilities.

 

For me, it's just a shame to see this car in a sorry state now.  I'd be happier putting a stock BLT engine back in, and taking it back to a VGC standard late fabia 1.

You've mentioned this a few time Jase but I am curious how a longer injection period, which is essentially (in my understanding) still injecting fuel as the piston moves down when there is less compression going to lead to cracking a block.

 

?? On a Diesel engine the fuel is injected on the compression stroke as the piston is nearing the top of the bore.

Sorry to hear about your car mate, hope you get it back and running soon

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You've mentioned this a few time Jase but I am curious how a longer injection period, which is essentially (in my understanding) still injecting fuel as the piston moves down when there is less compression going to lead to cracking a block.

I feel that you are adding 2 and 2 and coming up with an answer as the "secret" map is the only link.

But that doesn't really mean that it's actually the reason.

You have not seen the injection cycles, map, etc...

Admittedly it's not unusual for you to have an opinion though.

Im just throwing ideas out there.

Just looking at the facts.

Every other tuner says stock nozzles are maxxed at 220/230bhp

Somehow jabbasport can run 250/260bhp plus on them.

So straight away something doesnt add up.

The car has done 13k miles since the jabbasport visit, and its pretty much blew up??

Coincidence?

Also the OP says the turbo has died too?

Doesn't bode too well really and id imagine it wasn't a cheap visit to jabbasport.

Just throwing ideas out there, its a hell of a coincidence though you have to admit yourself.....

The injection duration is just something i've picked up from other forums, there are a lot of knowledgable guys over on tdiclub that will explain it properly.

But i believe their is a 'safe' injection duration, to get round uprating nozzles you can adjust the injection duration to gain more bhp. But in turn this increses cylinder pressure and engine temps.

Basically too much and boom....

All this is stuff i have read up on and is my understanding anyways

Edited 29 January, 201412 yr by BigJase88

Would love to know if warwick hunt's old jabba one has suffered the same fate

It's still on this forum in the hands of another Briskoda member.

Last I heard it's fine, but I suspect it's had a lot less track use.

?? On a Diesel engine the fuel is injected on the compression stroke as the piston is nearing the top of the bore.

 

Usually yes, but people keep going on about longer injection times.

If you run out of compression stroke... ???

 

I don't know how the map works.

I just figured if you inject for longer and run out of compression stroke, when are you injecting the fuel to make the extra power?

What would the acceptable egt limit be for interests sake?

What would the acceptable egt limit be for interests sake?

I think its about 800 degree's celcius. Was a few years since i looked at my old EGT

Edited 29 January, 201412 yr by BigJase88

Usually yes, but people keep going on about longer injection times.

If you run out of compression stroke... ???

I don't know how the map works.

I just figured if you inject for longer and run out of compression stroke, when are you injecting the fuel to make the extra power?

Lots of info in this thread

http://forums.tdiclub.com/showthread.php?t=298063

Usually yes, but people keep going on about longer injection times.

If you run out of compression stroke... ???

 

I don't know how the map works.

I just figured if you inject for longer and run out of compression stroke, when are you injecting the fuel to make the extra power?

anything injected after the ignition event would be wasted, the injection period is increased by advancing it ahead of tdc so that it's injected whils the piston is rising, obviously if you push it too far you would get pre-ignition, hence why folks run injectors with bigger nozzles, so the net amount of fuel injected is the same but it's done later and in a shorter space of time.

Would love to know if warwick hunt's old jabba one has suffered the same fate           

 

No Jase it hasn't, still going strong; though I would like larger injectors and a map tweak to suit admittedly, if for nothing else to reduce smoke under load. If anyone knows of a reputable firm who can do this, please PM me.

 

Darren, really sorry to read all this, hope you get the car back running well very soon.

Common rail diesel injection works by allowing the ECU to control the ignition point much like advancing the ignition on a petrol engine, however because the flame speed in a diesel is much lower than in a petrol this puts a practical limit on how high a diesel engine can rev compared to a petrol. in practice this creates a 'window' for injection which is fixed in relation to when the ECU starts injecting and when combustion is complete, as Tom says any extra fuel injected after this 'window' shuts is not burnt properly and manifests as black exhaust smoke and is therefore wasted.

 

Lean conditions in turbodiesels lead to very high combustion chamber temps and very high EGT which destroys VNT's, the cracking of blocks and heads is almost always caused by very high temperature differentials which suggests this engine was leaning off too much at high RPM, this is what happens when the injectors cannot keep up with the air mass being shoved in by the turbo which I think is what Big Jase was getting at.

 

Cam wear in a PD can also cause leaning due to the unit injector not being fully actuated, this is dangerous in high states of tune if there is no 'headroom' in the map for reduced injector efficiency.

Would love to know if warwick hunt's old jabba one has suffered the same fate

No Jase it hasn't, still going strong; though I would like larger injectors and a map tweak to suit admittedly, if for nothing else to reduce smoke under load. If anyone knows of a reputable firm who can do this, please PM me.

Darren, really sorry to read all this, hope you get the car back running well very soon.

Darkside developments.

Get some firad nozzles whacked in there!

Some +80% baby's should do you

Would love to know if warwick hunt's old jabba one has suffered the same fate           

 

No Jase it hasn't, still going strong; though I would like larger injectors and a map tweak to suit admittedly, if for nothing else to reduce smoke under load. If anyone knows of a reputable firm who can do this, please PM me.

 

Darren, really sorry to read all this, hope you get the car back running well very soon.

Still waiting for the garage to finish putting it together - it's been 2 weeks since they had the engine and turbo - beginning to wonder what they are doing !! Guess by taking this long they can justify the £2k bill. (maybe I am just being cynical).

Still waiting for the garage to finish putting it together - it's been 2 weeks since they had the engine and turbo - beginning to wonder what they are doing !! Guess by taking this long they can justify the £2k bill. (maybe I am just being cynical).

 

That price is BS mate seriously.

 

If I was in your boat after I got my car back, since you are now I guess past the point of avoiding the ass shafting this place is handing out to you, I would let them know in certain terms face to face that you now know that a decent mechanic could have had that engine and turbo out and replaced within 8 hours easy, I know guys that could have that engine out in 2 to 3 hours and built back up within 4.

 

I would let them know that you have done your research and that you are now aware of this information and that you now know that this job should never of cost you even half of what they are charging, and that you intend to let everyone you know who drives what a dirty little dishonest business they are running and to stay well away.

Edited 10 February, 201412 yr by KillerShark1978

That price is BS mate seriously.

 

If I was in your boat after I got my car back, since you are now I guess past the point of avoiding the ass shafting this place is handing out to you, I would let them know in certain terms face to face that you now know that a decent mechanic could have had that engine and turbo out and replaced within 8 hours easy, I know guys that could have that engine out in 2 to 3 hours and built back up within 4.

 

I would let them know that you have done your research and that you are now aware of this information and that you now know that this job should never of cost you even half of what they are charging, and that you intend to let everyone you know who drives what a dirty little dishonest business they are running and to stay well away.

 

That's not true and it's not fair.

 

There is simply no way to replace the two cracked castings in the time you state, let alone refit everything and get the car running and driving again.

 

I would imagine the garage has outsourced the block and head rebuild since they won't have the facilities to do that kind of work, that means they are almost certainly waiting for it all to come back before they can refit it.

 

That price is also more than fair since a complete recon. bare engine alone is about £1500 outright.

Edited 10 February, 201412 yr by sepulchrave

That's not true and it's not fair.

 

There is simply no way to replace the two cracked castings in the time you state, let alone refit everything and get the car running and driving again.

 

I would imagine the garage has outsourced the block and head rebuild since they won't have the facilities to do that kind of work, that means they are almost certainly waiting for it all to come back before they can refit it.

 

That price is also more than fair since a complete recon. bare engine alone is about £1500 outright.

 

Sorry, but I've got to agree with sepulchrave on this.

 

And IME you always come across some simply job that becomes longer due to x y and z.

I think its a bit much to pay, from what ive read its been two weeks since they have had the engine and turbo and not much has happened.

and wasnt it the person doing all the running around for parts and not the garage.

Only way to really explain the 2k if thats true is for storage of the vehicle.

I think its a bit much to pay, from what ive read its been two weeks since they have had the engine and turbo and not much has happened.

and wasnt it the person doing all the running around for parts and not the garage.

Only way to really explain the 2k if thats true is for storage of the vehicle.

 

My understanding is that the OP sourced a secondhand 'donor' engine and a new turbo and left the rest to the garage to sort out, which means an awful lot of work and an awful lot of parts to bring the 'donor' engine up to spec. for this type of power build.

 

Garages don't get involved in engine building so that will have been outsourced as I stated, engine builders get paid considerably better than garage fitters because the work they do is much more demanding and painstaking.

 

Your 'scrapyard monkey' assessment of the cost is unrealistic and based on nothing other than that 'you feel like' it's too much, frankly the OP is lucky to find a garage prepared to take on a job like this and the price is a fair reflection of the time and trouble the garage will have to take on the job. Most garages would just throw a huge quote at the customer to get him to go away.

 

I have dealt with 'built' racing engines where the price tag was 35-50k for an engine alone, no fitting.

I have already paid for the engine and turbo.

The cost is for putting it back together again. However they did say they had already spent a day stripping the car

They did also state that when they put it back together they would do the cambelt, clutch release bearings etc etc and would rather put new stuff on rather than use the old. Obviously I am no mechanic and rely on their expertise and take it that what they are saying is what is required.

.

Assuming the 2k is for labour and cambelt and odd other bits.

Garage i use i would consider a little over average for pricing at £55 per hour.

day to strip it down 440.

Cambelt lets say around 400 aswell.

Other bits give it 300 a big chunk.

which leaves 860 to put everything back together, so just over 15 hours.

fair enough for the cost but wouldnt even you expect to have it back within two week?

Or am i just being a tight fisted yorkshireman.