bullet proofing a D1 or D2
#41
04-08-2021 | 01:41 PM
Pro Wrench
Joined: Apr 2018
Posts: 1,423
Likes: 399
From: SE PA
Most of the technical points have been covered above but one thing that hasn't been emphasized is that 9 times out of 10 you don't just show up and buy a $1,500 Disco, throw some money at it and double your investment. It certainly can be done, especially depending on the scale, but building a bullet-proof anything typically takes years of know-how, and understanding what works and what doesn't. What to look for and what to watch out for.
The get rich quick scheme that seems to be underlying your motivation here is more likely to cause a lot of anguish and wasted dollars as you learn the ins and outs of these trucks. I don't mean that to sound accusatory but as you've already found out, there's a lot of conflicting information out there and watching all the youtube videos you can find won't account for experience gained the garage and on the road. This forum is the best one I've found when it comes to no-nonsense, real world solutions that work, proven out by guys that have been doing it for years, so that certainly helps flatten the curve. These trucks aren't complicated vehicles so your best bet is to buy a few and start turning wrenches, not clicking links. Until you've experienced this circus for yourself you're no better off than anyone else speculating on a market. There is no bible or one particular methodology that can be applied to the these old trucks with the expectation that you've made it bullet-proof. There are basic tenants which work that pretty much everyone subscribes to, like coolant temps being the single most important factor, but everyone has their own approach to certain aspects which are guided by their own experiences. Quite possibly the best way to create a Disco that sells for $20k is to spend $30k building it.
The get rich quick scheme that seems to be underlying your motivation here is more likely to cause a lot of anguish and wasted dollars as you learn the ins and outs of these trucks. I don't mean that to sound accusatory but as you've already found out, there's a lot of conflicting information out there and watching all the youtube videos you can find won't account for experience gained the garage and on the road. This forum is the best one I've found when it comes to no-nonsense, real world solutions that work, proven out by guys that have been doing it for years, so that certainly helps flatten the curve. These trucks aren't complicated vehicles so your best bet is to buy a few and start turning wrenches, not clicking links. Until you've experienced this circus for yourself you're no better off than anyone else speculating on a market. There is no bible or one particular methodology that can be applied to the these old trucks with the expectation that you've made it bullet-proof. There are basic tenants which work that pretty much everyone subscribes to, like coolant temps being the single most important factor, but everyone has their own approach to certain aspects which are guided by their own experiences. Quite possibly the best way to create a Disco that sells for $20k is to spend $30k building it.
#42
04-08-2021 | 01:47 PM
That doesn't explain the reputation for always eventually going to need a new engine eventually due to a crack in the cylinder and/or head-gasket. One reason to need to "keep coolant" in the car could be if it's boiling away or leaking away through a crack in the cylinder. I have an American V8 now and I never have to add coolant... never. I have to add oil all the time, since it leaks oil, however.
I'm still going with the incompatible antifreeze corroding and weakening the cylinder walls. Then it gets low on coolant since it's being leaked into the hot cylinder boiled away and then detonates due to the heat and the head gasket is part of this whole process of overheating. That explains the common failures, but I'm just guessing. Maybe some cars never used that particular anti-freeze?
I'm still going with the incompatible antifreeze corroding and weakening the cylinder walls. Then it gets low on coolant since it's being leaked into the hot cylinder boiled away and then detonates due to the heat and the head gasket is part of this whole process of overheating. That explains the common failures, but I'm just guessing. Maybe some cars never used that particular anti-freeze?
I've owned well over 20+ Land Rovers with 3.9L to 4.6L V8's ranging from 0 miles on them to nearly 250k. I never once had to replace a LR V8 engine. Keep em cool, keep em maintained, and #1 DO NOT buy a 500.00 project LR & expect it to be flawless. It's 500.00 for a reason... A lot of folks get into LR's by buying someone elses project they abandoned. Then instantly bash the LR vs the 12 previous owners & their poor maintenance. Now sometimes you can buy a 500.00 LR that simply just needs a battery and some gas, but in all my years and many many many LR's I've only come across 3 like that (2 of which I still own and drive with zero issues). Normally with an older LR you get what you pay for. 3k is the lowest I've paid for a super clean 95 D1 100% original and zero rust on it. I however would have dumped 3.6k worth of $$$$$ into it had I not done the engine work on it myself. I had to tear it down and replace the entire #5 piston as somewhere in it's past a tech dropped a bolt into the engine and it destroyed the piston... They just replaced the damaged head, but left the piston. I repaired it & that 3.9L runs flawless now!
I DO NOT trailer my LR's to any off road events & I go 6+ hours each way. I have faith in all my LR's and in the event something does fail (even new vehicles can break down) I am fully prepared to repair it & get back on the road quickly.
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#43
04-08-2021 | 03:06 PM
That doesn't explain the reputation for always eventually going to need a new engine eventually due to a crack in the cylinder and/or head-gasket. One reason to need to "keep coolant" in the car could be if it's boiling away or leaking away through a crack in the cylinder. I have an American V8 now and I never have to add coolant... never. I have to add oil all the time, since it leaks oil, however.
I'm still going with the incompatible antifreeze corroding and weakening the cylinder walls. Then it gets low on coolant since it's being leaked into the hot cylinder boiled away and then detonates due to the heat and the head gasket is part of this whole process of overheating. That explains the common failures, but I'm just guessing. Maybe some cars never used that particular anti-freeze?
I'm still going with the incompatible antifreeze corroding and weakening the cylinder walls. Then it gets low on coolant since it's being leaked into the hot cylinder boiled away and then detonates due to the heat and the head gasket is part of this whole process of overheating. That explains the common failures, but I'm just guessing. Maybe some cars never used that particular anti-freeze?
#44
04-08-2021 | 03:10 PM
Also, the AFR being the same doesn't guarantee there will not be detonation... my current V8 is pinging now on hot days only and only when going up an incline on the highway and only sometimes and now it has about 175,000 miles on it, the pinging is probably because it hasn't had new spark plugs and the air filter changed since at least 113,000 miles when I bought it... adding octane booster turns it into a zippy almost completely different engine (even with the old spark plugs, which I still haven't changed since I don't drive it much.) So a lot of different things can cause detonation despite the computer trying to keep a consistent AFR. Just thinking as I type.
#45
04-08-2021 | 09:45 PM
Thread Starter
|
Three Wheeling
Joined: Apr 2021
Posts: 83
Likes: 1
AFR almost never causes detonation, its the hotspots in the cylinders and high cylinder pressures at low rpm. Hot sports in the cylinder heads are not a problem with aluminum heads (assuming the engine is at 180 degrees) and LR programs the transmission TCU to kick the engine down a gear if you are over 75% throttle and under 3000 rpm. The result is any time the cylinder pressures are high, the engine is spinning 4000 rpm plus and detonation is rare at those rpms unless you have a ton of compression, boost, or temperature.
Detonation is generally caused by excessive heat, excessive cylinder pressure, improper ignition timing, inadequate fuel octane or a combination of these. Of the previous, excessive heat is usually the culprit. As an engine is modified to generate more power, additional heat is produced.
https://www.procharger.com/what-deto...0is%20produced.
https://www.procharger.com/what-deto...0is%20produced.
Detonation is a great thing if you’re taking in a fireworks show or maybe watching MacGyver.
Inside your engine? Not so much.
In fact, it’s probably best if you avoid detonation at all costs where your engine is concerned. Detonation occurs when excessive heat and pressure in the combustion chamber causes the air/fuel mixture to ignite on its own. Instead of a typical single flame kernel within the chamber, this creates multiple flames which collide with explosive force. This causes a sharp, sudden rise in cylinder pressure which subjects engine internals—pistons, rings, bearings, gaskets, etc.—to severe overload and creates a pinging or knocking sound. Worst case scenario: you’re looking at costly, if not catastrophic, engine damage.
Needless to say, it’s not an ideal situation. That’s why, in conjunction with Summit Racing and Fel-Pro, we’ve compiled a list of nine things you can do to avoid a detonation problem.
#1. Up Your Octane
The higher the octane number, the better the fuel’s ability to resist detonation.
Most engines are just fine on standard 87 octane; however, engines with high compression (9.0:1 and over) or forced induction (blowers or turbos) may require 89 or higher octane. Also, applications where the engine sees increased load or stress, such as towing or heavy hauling, may require additional octane levels. Basically, anything that causes higher combustion temperature and pressure or causes the engine to run hotter than normal can lead to detonation.
It may be time to up the octane.
#2. Keep Compression Reasonable
A static compression of 9.0:1 is typically the recommended limit for naturally aspirated street engines (although engines with knock sensors may be able to handle higher compression). For forced induction, a static ratio of 8.0:1 or less may be required depending on the amount of boost. A compression ratio over 10.5:1 can create detonation even with 93 premium gasoline.
The trick is to keep the compression ratio within a reasonable range for pump gas unless your engine is being built to operate on racing fuel. To accomplish this, you may need to use lower-compression pistons, opt for cylinder heads with larger combustion chambers, or try using a copper head gasket shim with the stock gasket to reduce compression. Also, if you’ve bored the engine cylinders or milled the cylinder heads, this increases compression and you may need to make accommodations.
#3. Check Your Timing
Over-advanced ignition timing can cause cylinder pressures to rise too rapidly and eventually lead to detonation. Reset your timing to stock specifications. If that doesn’t work, retard the timing a couple of degrees or try re-calibrating the distributor advance curve to keep detonation under control.
Supercharged AMX#4. Manage Your Boost
Controlling the amount of boost in a forced induction engine is critical.
Too much boost can lead to detonation, so you’ll need to either A) scale back boost, or B) outfit your engine to handle more boost. For example, in a turbocharged application, you’ll need to make sure your wastegate is operating properly to bleed off excess boost pressure. Leaks in vacuum connections, a defective intake manifold pressure sensor, or poorly performing wastegate solenoid control can cause the turbo to deliver too much boost. These things should be remedied. And you may also want to add a better performing intercooler while you’re at it.
For supercharged applications, check out our Blower Basics (Part 2) and Blower Basics (Part 3) stories for guidelines on proper boost levels and how they relate to compression.
#5. Monitor the Mixture
Lean air/fuel mixtures are prone to detonation.
Check your air/fuel mixture and adjust accordingly. A lean condition could be a symptom of a larger problem such as air leaks in vacuum lines or poor-performing gaskets. It could also be caused by dirty fuel injectors, clogged carb jets, or a restricted fuel filter. If your engine is experiencing hesitation or rough idle, you may be dealing with a lean fuel condition and will want to make appropriate adjustments or fixes before detonation occurs.
Engine Detonation
Carbon deposits around valve. (Image courtesy of carsandparts.com)
#6. Blow out the Carbon
Carbon deposits are a common cause of detonation in high-mileage engines.
Essentially, carbon deposits can accumulate in the combustion chamber and on top of pistons until the overall compression of the engine is altered. In addition, the deposits can create an insulating effect that slows heat transfer from the combustion chamber to the cylinder head. If deposits build up enough (and compression goes up enough), detonation can occur.
Like the lean fuel ratio above, carbon deposits could be a sign of another problem: worn valve guides, cylinder wear, broken piston rings, or infrequently changed oil. Check for the root cause of the deposits, fix any issues, and then remove the deposits with a chemical cleaner or via wire brush or scraper (requires removal of heads).
#7. Examine Your Knock Sensor
Many late model engines have a knock sensor which may become defective.
The knock sensor responds to vibrations within a certain frequency range. When the frequencies, which are typically produced by detonation, are detected, the knock sensor tells the vehicle’s computer to momentarily retard the ignition until detonation stops. If defective, this sensor would become ineffective.
If your vehicle’s “check engine” light is on, you may have a bad knock sensor (among other things). You could check the onboard computer system by reading the engine’s trouble code with the right tools. Or you can test the knock sensor by tapping a wrench on the manifold near the sensor and watching for a timing change. If the timing doesn’t retard, the sensor may be bad. You will need to find the proper diagnostic chart in a service manual for your vehicle to determine the cause.
#8. Read Your Spark Plugs
Engine Detonation
(Image courtesy of dynamicefi.com)
Be sure to read our earlier post on how to read spark plugs.
You can tell a lot about your engine’s performance by reading your plugs. For example, if your spark plugs appear yellowish, blistered, or broken, they may be too hot for the application. Try spark plugs with a colder heat range to avoid potential detonation. See our post on spark plug heat range for more tips.
#9. Consider Your Cooling System
If your engine is overheating, it is more likely to suffer spark knock. That’s why you should make sure your cooling system is in good order. Check your coolant level and fill if necessary. Make sure your fan is properly sized for the occasion. And look out for a bad water pump, missing fan shroud, too hot a thermostat, slipping fan clutch—basically anything that can prevent your cooling system from operating efficiently.
https://www.onallcylinders.com/2015/...ne-detonation/
Inside your engine? Not so much.
In fact, it’s probably best if you avoid detonation at all costs where your engine is concerned. Detonation occurs when excessive heat and pressure in the combustion chamber causes the air/fuel mixture to ignite on its own. Instead of a typical single flame kernel within the chamber, this creates multiple flames which collide with explosive force. This causes a sharp, sudden rise in cylinder pressure which subjects engine internals—pistons, rings, bearings, gaskets, etc.—to severe overload and creates a pinging or knocking sound. Worst case scenario: you’re looking at costly, if not catastrophic, engine damage.
Needless to say, it’s not an ideal situation. That’s why, in conjunction with Summit Racing and Fel-Pro, we’ve compiled a list of nine things you can do to avoid a detonation problem.
#1. Up Your Octane
The higher the octane number, the better the fuel’s ability to resist detonation.
Most engines are just fine on standard 87 octane; however, engines with high compression (9.0:1 and over) or forced induction (blowers or turbos) may require 89 or higher octane. Also, applications where the engine sees increased load or stress, such as towing or heavy hauling, may require additional octane levels. Basically, anything that causes higher combustion temperature and pressure or causes the engine to run hotter than normal can lead to detonation.
It may be time to up the octane.
#2. Keep Compression Reasonable
A static compression of 9.0:1 is typically the recommended limit for naturally aspirated street engines (although engines with knock sensors may be able to handle higher compression). For forced induction, a static ratio of 8.0:1 or less may be required depending on the amount of boost. A compression ratio over 10.5:1 can create detonation even with 93 premium gasoline.
The trick is to keep the compression ratio within a reasonable range for pump gas unless your engine is being built to operate on racing fuel. To accomplish this, you may need to use lower-compression pistons, opt for cylinder heads with larger combustion chambers, or try using a copper head gasket shim with the stock gasket to reduce compression. Also, if you’ve bored the engine cylinders or milled the cylinder heads, this increases compression and you may need to make accommodations.
#3. Check Your Timing
Over-advanced ignition timing can cause cylinder pressures to rise too rapidly and eventually lead to detonation. Reset your timing to stock specifications. If that doesn’t work, retard the timing a couple of degrees or try re-calibrating the distributor advance curve to keep detonation under control.
Supercharged AMX#4. Manage Your Boost
Controlling the amount of boost in a forced induction engine is critical.
Too much boost can lead to detonation, so you’ll need to either A) scale back boost, or B) outfit your engine to handle more boost. For example, in a turbocharged application, you’ll need to make sure your wastegate is operating properly to bleed off excess boost pressure. Leaks in vacuum connections, a defective intake manifold pressure sensor, or poorly performing wastegate solenoid control can cause the turbo to deliver too much boost. These things should be remedied. And you may also want to add a better performing intercooler while you’re at it.
For supercharged applications, check out our Blower Basics (Part 2) and Blower Basics (Part 3) stories for guidelines on proper boost levels and how they relate to compression.
#5. Monitor the Mixture
Lean air/fuel mixtures are prone to detonation.
Check your air/fuel mixture and adjust accordingly. A lean condition could be a symptom of a larger problem such as air leaks in vacuum lines or poor-performing gaskets. It could also be caused by dirty fuel injectors, clogged carb jets, or a restricted fuel filter. If your engine is experiencing hesitation or rough idle, you may be dealing with a lean fuel condition and will want to make appropriate adjustments or fixes before detonation occurs.
Engine Detonation
Carbon deposits around valve. (Image courtesy of carsandparts.com)
#6. Blow out the Carbon
Carbon deposits are a common cause of detonation in high-mileage engines.
Essentially, carbon deposits can accumulate in the combustion chamber and on top of pistons until the overall compression of the engine is altered. In addition, the deposits can create an insulating effect that slows heat transfer from the combustion chamber to the cylinder head. If deposits build up enough (and compression goes up enough), detonation can occur.
Like the lean fuel ratio above, carbon deposits could be a sign of another problem: worn valve guides, cylinder wear, broken piston rings, or infrequently changed oil. Check for the root cause of the deposits, fix any issues, and then remove the deposits with a chemical cleaner or via wire brush or scraper (requires removal of heads).
#7. Examine Your Knock Sensor
Many late model engines have a knock sensor which may become defective.
The knock sensor responds to vibrations within a certain frequency range. When the frequencies, which are typically produced by detonation, are detected, the knock sensor tells the vehicle’s computer to momentarily retard the ignition until detonation stops. If defective, this sensor would become ineffective.
If your vehicle’s “check engine” light is on, you may have a bad knock sensor (among other things). You could check the onboard computer system by reading the engine’s trouble code with the right tools. Or you can test the knock sensor by tapping a wrench on the manifold near the sensor and watching for a timing change. If the timing doesn’t retard, the sensor may be bad. You will need to find the proper diagnostic chart in a service manual for your vehicle to determine the cause.
#8. Read Your Spark Plugs
Engine Detonation
(Image courtesy of dynamicefi.com)
Be sure to read our earlier post on how to read spark plugs.
You can tell a lot about your engine’s performance by reading your plugs. For example, if your spark plugs appear yellowish, blistered, or broken, they may be too hot for the application. Try spark plugs with a colder heat range to avoid potential detonation. See our post on spark plug heat range for more tips.
#9. Consider Your Cooling System
If your engine is overheating, it is more likely to suffer spark knock. That’s why you should make sure your cooling system is in good order. Check your coolant level and fill if necessary. Make sure your fan is properly sized for the occasion. And look out for a bad water pump, missing fan shroud, too hot a thermostat, slipping fan clutch—basically anything that can prevent your cooling system from operating efficiently.
https://www.onallcylinders.com/2015/...ne-detonation/
Engine Detonation
Definition & Description
Detonation is spontaneous combustion inside the cylinder AFTER the spark plug fires. It is similar to Pre-Ignition, but it is different.
During normal ignition, the spark plug fires just before the piston reaches TDC. The flame travels across the combustion chamber igniting the Air/Fuel Mixture. This causes a steady increase in cylinder pressure and forces the piston down on the Power Stroke.
When detonation happens, some of the air/fuel ignites before the normal burn can get to it. This causes a brief, but intense, spike in cylinder pressure.
Detonation is also called an "Engine Knock", "Knocking", or "Pinging" because of the sound it makes.
How is it indicated?
Knocking or pinging sound
Drop in Exhaust Gas Temperature (EGT)
Broken piston rings and/or spark plugs
Damage to the piston and/or valves
What causes it?
Detonation can be caused by several factors. A few common causes are:
Over-Advanced Ignition Timing
If Ignition Timing is too far advanced, the spark plug fires too soon. This causes the flame to end early. The remaining fuel can detonate.
Lean Air/Fuel Mixture
A rich Air/Fuel Mixture runs cooler than a lean mixture. A lean mixture can get too hot and detonate.
Too Much Compression
Compression causes heat. If the air/fuel mixture is compressed too much, it can detonate.
Engine Overheating
Low coolant or a bad water pump can cause the engine to overheat. Too much heat can cause the air/fuel in the chamber to detonate.
Low Octane Fuel
Octane Rating is a measure of "knock resistance". Switching to higher grade fuel can help a knocking engine.
How does it affect performance?
An engine is designed to work in a specific way. Because detonation interrupts that design, it robs the engine of power.
Most engines can handle some minor detonation. Modern, fuel injected engines can sense a knock and adjust the Air/Fuel Ratio and Ignition Timing. However, if the detonation is not fixed, it will damage the engine. Just one major detonation event could cause significant damage.
Answer ID 5007 | Published 05/30/2018 12:58 PM | Updated 11/12/2019 02:46 PM
https://help.summitracing.com/app/an...ine-detonation
Definition & Description
Detonation is spontaneous combustion inside the cylinder AFTER the spark plug fires. It is similar to Pre-Ignition, but it is different.
During normal ignition, the spark plug fires just before the piston reaches TDC. The flame travels across the combustion chamber igniting the Air/Fuel Mixture. This causes a steady increase in cylinder pressure and forces the piston down on the Power Stroke.
When detonation happens, some of the air/fuel ignites before the normal burn can get to it. This causes a brief, but intense, spike in cylinder pressure.
Detonation is also called an "Engine Knock", "Knocking", or "Pinging" because of the sound it makes.
How is it indicated?
Knocking or pinging sound
Drop in Exhaust Gas Temperature (EGT)
Broken piston rings and/or spark plugs
Damage to the piston and/or valves
What causes it?
Detonation can be caused by several factors. A few common causes are:
Over-Advanced Ignition Timing
If Ignition Timing is too far advanced, the spark plug fires too soon. This causes the flame to end early. The remaining fuel can detonate.
Lean Air/Fuel Mixture
A rich Air/Fuel Mixture runs cooler than a lean mixture. A lean mixture can get too hot and detonate.
Too Much Compression
Compression causes heat. If the air/fuel mixture is compressed too much, it can detonate.
Engine Overheating
Low coolant or a bad water pump can cause the engine to overheat. Too much heat can cause the air/fuel in the chamber to detonate.
Low Octane Fuel
Octane Rating is a measure of "knock resistance". Switching to higher grade fuel can help a knocking engine.
How does it affect performance?
An engine is designed to work in a specific way. Because detonation interrupts that design, it robs the engine of power.
Most engines can handle some minor detonation. Modern, fuel injected engines can sense a knock and adjust the Air/Fuel Ratio and Ignition Timing. However, if the detonation is not fixed, it will damage the engine. Just one major detonation event could cause significant damage.
Answer ID 5007 | Published 05/30/2018 12:58 PM | Updated 11/12/2019 02:46 PM
https://help.summitracing.com/app/an...ine-detonation
So far I'm still with the corrosive anti-freeze explanation. It's the only explanation that explains all the scenarios experienced in real life. Detonation in a sleeved cylinder won't crack the cylinder walls, in my opinion. Do I know? No, this is just a thought process.
Next I'll be researching more into the F1 winning car that used this engine (without cracking the cylinder heads and without overheating.) I read that they used some titanium in the block, but that's all I know so far.
It still make no sense to me that an engine that is rated as the best engine of all time in the UK and is used in race cars, drag cars, F1 racers, and in other street cars and trucks suddenly started to go back in it's last years and that there is no solution to it.
I've seen RP1's videos and all they SEEM to do is pre-test old blocks to see if they have leaky walls or not then they sleeve them and build a standard engine. You guys call it a top hat, but that kind of sleeve with a lip on top is common in all kinds of cars and trucks.
I saw the page that said the machining was off, due to the machine marks and lack of machine marks in certain places on the block, but if that's so then it's more than the machining, it's the entire mold being off since the machined holes are dead center where the bolts go.
That's where I am now, having fun researching this.
#46
04-08-2021 | 10:08 PM
Pro Wrench
Joined: Apr 2018
Posts: 1,423
Likes: 399
From: SE PA
#47
04-08-2021 | 10:17 PM
Rock Crawling
Joined: Mar 2012
Posts: 363
Likes: 84
The f1 engine had overhead cams and a hell of a timing cover. Its hardly a rover engine. 215 also had a much thicker wall between the liner and coolant passage, and the non rover 215 had cast in place serrated liners.
keep it under 210F and full of clean oil and itll last hundreds of thousands of miles.
keep it under 210F and full of clean oil and itll last hundreds of thousands of miles.
#48
04-09-2021 | 01:06 AM
Thread Starter
|
Three Wheeling
Joined: Apr 2021
Posts: 83
Likes: 1
The f1 engine had overhead cams and a hell of a timing cover. Its hardly a rover engine. 215 also had a much thicker wall between the liner and coolant passage, and the non rover 215 had cast in place serrated liners.
keep it under 210F and full of clean oil and itll last hundreds of thousands of miles.
keep it under 210F and full of clean oil and itll last hundreds of thousands of miles.
I hear you, but you don't need thick walls if you have sleeves (liners)... cylinder walls are unlikely to crack in sleeved blocks. Why would the sleeve itself not crack but the cylinder wall behind the sleeve crack, makes no sense. Cast in place or machined into place shouldn't make a difference. The sleeves slipped because the water came in behind them. The water came in behind them for an unknown reason. RP1, for example, doesn't try to find out why the walls are porous, they just pressure test all the blocks and discard the porous blocks, similar to how I've heard Ranger Rover did with the x-ray scanner. Still nobody found the real reason, the root cause.
I don't think overhead cams has an effect on the cylinder walls, but I don't really know. I don't know anything, just having fun researching this mystery.
If you can get one of these for cheap I think you can do a lot to it without spending more than it's worth (if you do the work yourself which is what I always do) and I'm a big fan of keeping everything stock.
My biggest question is still will that Revel Machines company actually sell a Discovery for $19k. There is a near mint silver 2004 Discovery 2 on CL for sale in the LA area with low mileage, btw. These solid axle Discovery vehicles had some of the best interiors ever seen in a car or truck. I'm not sure the 2021 models still do.
#49
04-09-2021 | 01:17 AM
Thread Starter
|
Three Wheeling
Joined: Apr 2021
Posts: 83
Likes: 1
Read this...
Landrover will deny there is a problem like they did with me seven years ago when mine went.Once you get your new engine fitted then get the E.C.U re-mapped.its now common knowledge that the main reason for pourous blocks is that the mapping on the 4.6 runs too lean through the mid ranges causing exessive heat build up in the cylinders,causing the block issues.Or for those with the problems just starting to occur you can use liquid glass.Ive known it to be applied to about eight P38,s without any come backs.
https://www.pistonheads.com/gassing/topic.asp?t=304296
https://www.pistonheads.com/gassing/topic.asp?t=304296
#50
04-09-2021 | 01:18 AM
Thread Starter
|
Three Wheeling
Joined: Apr 2021
Posts: 83
Likes: 1
And this on the same page:
What is this porous block syndrome? I know of the problem with some blocks and liners coming seperated but not this one.
Its more of a problem in aluminum blocks and heads than cast iron. Basically during the casting process bubbles form in the molten metal and when it cools it leaves a portion of the casting in a sponge like state. If not caught in quality control and put into service these porous blocks or heads can eventually leak or even fail.
https://www.pistonheads.com/gassing/topic.asp?t=304296
Its more of a problem in aluminum blocks and heads than cast iron. Basically during the casting process bubbles form in the molten metal and when it cools it leaves a portion of the casting in a sponge like state. If not caught in quality control and put into service these porous blocks or heads can eventually leak or even fail.
https://www.pistonheads.com/gassing/topic.asp?t=304296