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removing exhaust liners?


lowrider

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That is describing a standard N/A spec engine in several different JDM applications. That a turbo was added (all that turbo stuff is an external bolt on!) to an N/A engine should not be a surprise.

 

No Nissan Turbo Engine came with liners in the exhaust.

 

If the L20ET came with liners, why in the WORLD would they bother with the P90 or the O5L? From a corporate bookeeping standpoint that would make ABSOLUTELY no sense.

 

The ONLY reason a P90 or O5L head exists was for Turbos. Otherwise worldwide the easiest thing to do would be manufacture and stock a single universal head: the one with liners in it.

 

Beware of making assumptions that anything coming out of Japan through a used engine outlet or in a vehicle was the way it came from the "factory" unless you were the one taking delivery in person when it was new!Using your criteria, my Maxima Wagon with the L20E and Y70 Head sitting in the JY in SoCal was a factory fittment as well. Professionals doing work will leave no trace.

 

Remember I worked for an OEM (and still do in a different field...) and there are things that happen before cars are delivered (and in some cases back in a service bay while the customer waits outside due to 'insurance regulations') that would make people shudder. And from all appearances, they look "Factory Stock and Fresh" when they see them up on the rack the first service call after buying them!

 

Ever consider the reason most shops have the 'Due to Insurance Requirements we regret to inform customers that they are not allowed on the workfloor' is more with someone observing an arguable negligent act by a 'competent tradesman' which could result in far more litigation and liability down the road than any simple slip-and-fall? But I digress...

 

What you're saying is entirely feasable, so too is the chance that this was something truely different, just like that E32 4 barrel intake manifold I showed you Tony.

 

What I see with the little ET engine is a block with a boss cast into it for a knock sensor and deeply dished pistons. The sump was the turbo variety too. A lot of extra trouble from the factory to 'mask' a N/A engine and turn it into a turbo version. Heck, even the camshaft, headbolts, camcover and oil pump were turbo spec. And what about that water to oil cooler? (The only other car I saw this on was a picture of an engine bay in New Zealand. I can't remember what car it was, but I remember it was an L20AET.)

 

We had a funny thing happen in the early eighties over here. A shipload of PA10 coupes were sent to these shores by mistake. Some 200 of them I believe. They arrived and we ended up keeping them. Someone must have known they were the wrong shipment but how did that happen? What I'm trying to say here is just because it is known that no L turbo engines came with liners, there is every possibility that some did. Just like the Stanza coupes that weren't meant to be here.

 

I hope this doesn't sound argumentative as it's not meant to be.

 

I just think I have one of those unusual spec. engines in my garage.

 

Looking for 2 litre heads?, I too have an O5L and a spare Y70.... mine would be cheaper than his......! ;):P:)

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People do things...because of ease at the time.

When did you buy this engine/car?

 

If it wasn't 1981 through 1983 straight off the dealer floor, consider the fact that a service replacement head was put on a turbo block.

 

This CAN be done without a subsequent owner knowing, and it is the most logical explanation for it's presence.

 

I have seen P79 heads on turbo cars, I know better than to claim they were put there in manufacturing.

 

Same as I know that Y70 L20E was not factory in the Maxima Wagon (engine code said L24E on the California Emissions Sticker...)

 

Same as I know just because TA22 Celicas in Montana came with 2T motors, the presence of a 2TG DOHC engine means it could have migrated down from Canada OR been a swap as only ONE was ever imported to the USA (TA22-00005)

 

Never underestimate the ability of a professional to make it appear as if nothing has ever been touched before.

 

On an L-Engine that's deceptively easy.

 

Now, on the other hand, if you can trot out some Nissan Documents that show experimental engines, some development program, or irrefutably rebut the 'Financial Logic' of the prior post of mine consider the possiblity that the Y70 was a replacement. And making definitive statements like that without proof other than asupposition may provide bad information to someone somewhere down the line.

 

The logical deduction is that sometime early in it's life, a Y70 was more expeditiously available and was swapped to a turbo engine. This would not be untoward, and would not affect the vehicle's ability to pass inspection in Japan. But from the factory? I'm in the 99.99999999999% position that it wasn't, but I leave that 0.00000000001% open for someone with documentation to show it may have happened for one reason or another. But I wouldn't make bets on anybody ever showing up to contradict what Nissan has already stated as fact: No liners from the factory on Turbocharged Engines due to the EGTs involved.

 

If they differentiated oil cooled differentials from non, and oil coolers on engines from non...depending on market and vehicle to increase longevity or simply make things last -- I think they had a handle on what not to put on an engine to decrease longevity and would religiously stick to the plan.

 

Why would your ONE example have it? Doesn't make sense unless someone changed it. And that change logically would occur post-factory. Dealerships do a LOT of gnarly things customers don't know. They DID exchange crankshafts in the 240 you know. Not service engine assemblies, crankshafts -- that takes some work to not leave a trace new, but after 20,000 miles? Not a chance in hell you could tell upon disassembly it was monkeyed with!

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People do things...because of ease at the time.

When did you buy this engine/car?

 

If it wasn't 1981 through 1983 straight off the dealer floor, consider the fact that a service replacement head was put on a turbo block.

 

This CAN be done without a subsequent owner knowing, and it is the most logical explanation for it's presence.

 

I have seen P79 heads on turbo cars, I know better than to claim they were put there in manufacturing.

 

Same as I know that Y70 L20E was not factory in the Maxima Wagon (engine code said L24E on the California Emissions Sticker...)

 

Same as I know just because TA22 Celicas in Montana came with 2T motors, the presence of a 2TG DOHC engine means it could have migrated down from Canada OR been a swap as only ONE was ever imported to the USA (TA22-00005)

 

Never underestimate the ability of a professional to make it appear as if nothing has ever been touched before.

 

On an L-Engine that's deceptively easy.

 

Now, on the other hand, if you can trot out some Nissan Documents that show experimental engines, some development program, or irrefutably rebut the 'Financial Logic' of the prior post of mine consider the possiblity that the Y70 was a replacement. And making definitive statements like that without proof other than asupposition may provide bad information to someone somewhere down the line.

 

The logical deduction is that sometime early in it's life, a Y70 was more expeditiously available and was swapped to a turbo engine. This would not be untoward, and would not affect the vehicle's ability to pass inspection in Japan. But from the factory? I'm in the 99.99999999999% position that it wasn't, but I leave that 0.00000000001% open for someone with documentation to show it may have happened for one reason or another. But I wouldn't make bets on anybody ever showing up to contradict what Nissan has already stated as fact: No liners from the factory on Turbocharged Engines due to the EGTs involved.

 

If they differentiated oil cooled differentials from non, and oil coolers on engines from non...depending on market and vehicle to increase longevity or simply make things last -- I think they had a handle on what not to put on an engine to decrease longevity and would religiously stick to the plan.

 

Why would your ONE example have it? Doesn't make sense unless someone changed it. And that change logically would occur post-factory. Dealerships do a LOT of gnarly things customers don't know. They DID exchange crankshafts in the 240 you know. Not service engine assemblies, crankshafts -- that takes some work to not leave a trace new, but after 20,000 miles? Not a chance in hell you could tell upon disassembly it was monkeyed with!

 

A very convincing argument Tony.

 

Very few owners could ever afford to keep their cars for many years like we do due to taxes and levy's in the mother country.

 

Longevity may not have been something that was of major concern to the engineers when they were selecting heads for some of their JDM turbo engines. They may have known the problems associated with liners and EGT's, but thought what the heck, they pass inspection now and before the liners cause trouble, most of the cars will be off the road anyway. If this becomes an issue, we can afford to deal with one off's as they occur...... mentality.

 

Now that I've planted the seed of doubt, is there anyone who can shut down this idea completely with some concrete evidence to the contrary? I don't really think too many people care either way, but I would like to know for certain what I have is factory or not.

 

Cheers.

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"Longevity may not have been something that was of major concern to the engineers when they were selecting heads for some of their JDM turbo engines. They may have known the problems associated with liners and EGT's, but thought what the heck, they pass inspection now and before the liners cause trouble, most of the cars will be off the road anyway. If this becomes an issue, we can afford to deal with one off's as they occur...... mentality."

 

Planted a seed of doubt? Hardly, but you have convinced me you have a fully-entrenched mindset of a westerner!

 

If this was the case, why have an O5L at all? The reason the non-linered heads exist is due to places where they can not be applied. If you knew the testing that goes into each engine permutation then the additional governmental compliance documentation and testing as well as for the home market type certification and classification you would realize at once what such a thought process came from: total disconnect with the realities of manufacturing within Japan in the automtoive market.

 

Want an example? In the 70's when the emissions laws were changing, one Japanese Manufacturer came into a bit of type compliance issues with US EPA. They produced REAMS of documentation showing the statistical impossiblity that their engines would not comply, such was their rigid regimentation and control processes (this is not Jaguar...or Ford...or GM-H!)

 

What it came down to was someone asked the testing laboratory in the USA 'what kind of fuel are you using, send us a sample.' (This was done in a roundabout way by an American who worked in the service department and had run into a similar issue in the past with vehicles imported from Europe...) The engineers in Japan were AGHAST at the fuel quality in the USA. But more importantly they realized when tested with that kind of fuel, their engines DID INDEED FAIL!

 

The Japanese Solution? Air Freight vats of fresh gasoline WEEKLY to use in their emissions calibration and testing regimens.

 

If the Japanese mindset is that they will airfreight fuel by the planeload to pass an emissions test...do you seriously think they would poo-poo catastrophic engine failure? In 1970 they changed ALL the cranks in the L24 Cars. They STOPPED PRODUCTION.

 

Do you really think with almost 10 years of progression in Quality Control that they would seriously compromise longevity in such a manner? To even suggest it indicates unfamilarity with the process at the least.

 

You are also missing the point on 'inspection'---this is not a 'western style' inspection. This is something where serial numbers and casting numbers are checked against a master list provided by the manufacturer. A Y70 would be listed as an acceptable L20A/E type cylinder head to have installed. So would almost any other head. An E88 would pass. So in that respect it would pass inspection.

 

So would a 2T-G engine insstalled in a Celica where formerly a 2T engine (SOHC Pushrod) would have been, or a 2T-BR (dual carb 2T) because the BLOCK TYPE is still 2T and Toyota wisely chose to certify the block only, and not the head. (Similar to Nissan...)

 

Outside the USA and Japan, where engine emissions was not a big issue.... there were no exhaust liners! They were P90 heads on L28's (Europe) or N42 Heads on L28's (Carburetted downdraught engines in Saloons in Saudi for example...)

 

The presence of Liners in an engine or marketplace occurred where there was a requirement for EMISSIONS COMPLIANCE in N/A engines. The turbocharged engines got ECCS for emissions control instead. And in Japan where emissions requirements were slightly more stringent in some respects, they got both Liners AND an ECCS in N/A cars.

 

But they never got liners in a turbocharged engine.

 

Can you prove why you so doggedly believe this was a factory setup? Did you get a certification paper from Nissan stating so? Were there lead seals and safetywire on removable components like some of the emissions testing machines? Or are you convinced solely due to patina and lack of monkey prints?

 

I can take you to a place in Michigan were (yes, even on Detroit Iron) there were Corvette components (like heads and manifolds) installed into Impalas before the sale (in direct contravention to federal emissions laws probably) and the owners would be in the same boat as you: Thinking they had a 'factory assembled engine' with these special components.

 

If you know what you are doing, use the proper tools, and do it early enough in an engine's lifetime there will NEVER be any suspicion that the head, intake, or for that matter radiator hoses or water pump had ever been changed.

 

That you have the only example in existence, and it goes in the face of what Nissan stated in parts manuals the world over supports the fact that someone changed your head. If they did it to one, they did it to 10,000 and they would have turned up elsewhere before this point in time. Including America where L20ET's were available from mid 82 onwards through Tomic Honda, K. Watanabe & Co, and myriad other JDM importers.

 

Do you seriously think the people with engine blocks that were made of diamond-hard metal would so radically alter a basic foundational engineering tenet as to discard it wholesale on an EXISTING product line in extended development? Seriously, is that what you are contending? Think about that long and hard.

 

That's a pecularily western thought process. And in Japan at that time, that was NOT how things were done! Remember I was there, and right now I'm typing this from Tokyo! What you suggest would be akin to the Prophet Mohammed popping up and saying "Howzabout some delicious pork ribs, forget all that HOGwash from me before! This is my latest prophecy so that overides everything prior! EAT UP! Pork-Akbar!"

 

It just don't happen!

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  • 8 years later...

Hello, 

 

Just thought I would add to this thread even tho it hasn't been active in a long time, but I know that a few people still stumble onto it every now and then. So most of the people building turbo ZX's have managed to find the actual turbo head or complete L28eT, but like me some others aren't so fortunate or wealthy to come across one. With that being said, I think I may have found a fairly simple way to remove these pesky exhaust liners that requires minimal curse words. I wanted to remove my liners and had just seen my friend remove his exhaust silencer out of his rotary and ya know what it looked like an identical process for removing the liners so I stole some of the rotary knowledge. 

 

What you have to do:

Get a die grinder (got an electric one from Harbor Freight $50ish) and some carbide bits (a couple of different shape or a cheap kit on ebay will suffice). Cut as far in as you can with the bits to section off the liners into small pieces and pull them out. If you place your cuts in the right area they are fairly easy to take out of the head. However, if you take them out you must port the head as the casting behind the liners is rather rough and not good for flow. I will link a short video I made on performing such process below. Also, if you wish to just beat them out expect roughly 40+ hours to remove them (tried one liner this way took five hours before I went searching for a new method), but if you do the method I performed then you can expect it to take you roughly three hours in total (no time at all when compared to porting and polishing an entire cylinder head). 

 

 

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  • 2 weeks later...
  • 1 month later...

The p90 is a sweet head, especially if you're doing a turbo engine since it won't require a custom manifold. Plus it flows well and has high quench. I lucked into a complete zx turbo on the cheap. Just had to dig it out of the woods with a backhoe. Haha 

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