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6.5 AMG Blocks that are on the market

great white said:
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great post by the way. feel the same way.

i get a little confused so please set me straight: chinese blocks are junk only because they say 'made in china', right? but if they were engeneered here in the states, they are good? there are some that are pricey, some are good and some not worth looking at? who sells the good ones, who doesn't? the AMG rejects are good, if the price is right, but need machining and it will bring the $ up to what a non-reject would cost? help me out, please. :bigear:[
 
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deejaaa said:
great white said:
..............vehicle...
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great post by the way. feel the same way.

i get a little confused so please set me straight: chinese blocks are junk only because they say 'made in china', right? but if they were engeneered here in the states, they are good? there are some that are pricey, some are good and some not worth looking at? who sells the good ones, who doesn't? the AMG rejects are good, if the price is right, but need machining and it will bring the $ up to what a non-reject would cost? help me out, please. :bigear:
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Well, I think what most are getting at here is that the overseas blocks are an unknown quantity.

What people are really talking about here is quality control, or the lack thereof.

Unless you're talking about the original castings, in which case they did exactly what the OE wanted them to do.

keep in mind; other engines crack blocks too. Just not as spectacularly or as commonly as the orignal 6.x design.

We may find out in several years the AMG casting is not much better in that department. There's just not enough time on the design yet to tell. It may very well be that the "china blocks" are better, or worse or a total crap shot. Unfortunately, the only way to know is for a bunch of rebuilds to get out there and log some "hard time".

I will say though that I've seen one optimizer from a factory pull (marine) that had a cracked #8 cylinder (2002 casting).....production run anomoly or......????

Then there's also the fact that non military owners are usually "educated" (IE: coolant temp, egt guages, etc) on what to do to make them live after having one puke it's guts out. I'm willing to bet most "optimizers" in civilian vehicles are going to led a better/easier life than the original engine that probably died a horrible death (unknowingly overheated, etc). The "china blocks" and optimizers may live longer than the orignal just on that fact alone.

I do belive there have been posts from Military techincians about HMMV's spitting out cranks also. Although, those might have been pre-AMG. You'd need one of them to weigh in to know for sure....

Anyways, this is becoming a bit of a hijack so it's probably time to stop...

:)
 
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Sadly though, a Buttload of 6.x engines have had the guts ran out of them and lived to tell about it.

The numbers that have failed are far less than those that have puked.

I know of one China block that's in a DaHoooooley like mine that routinely hauls around a 30 foot fiver and the owner has to throttle positions ON and OFF so that truck gets thrashed hard me thinks.

Time is the only thing that's gonna tell us much.

Missy
 
bison said:
Aha,i just stumbled on to the figures.....,.This is the composition ....

Ni = 0.03 (low low nickel... any iron with higher nickel is usually better.)
Weight/ China 506 block , 244 lb
Stock 506 block , 227 lb (did anybody notice this?... whoa.)
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If people start buying more P400's maybe the price will come down and they will stick around... hint hint.. :hello:

We pay for what we get, eh?
 
I believe the issue with the chinese parts is that if there isn't a vested American standing there watching the whole process, then the chinese will put in what they can get away with and cut corners any place they're able. They're all about "cheap" and if it takes an extra 10 seconds to finish a process correctly and they think they can get away without doing the process for one reason or another, then they're not going to do it. The minute he gets on a plane to come back home, all bets are off. They're very good at posturing for potential clients. My comment was based on that.

The other thing is that once the part(s) is on the boat, it's no longer their baby and they know the logistics of sending back for rework and/or warranty far exceed the cost of just absorbing it as a loss and buying more product.

I'm, in no way, trying to hijack this thread, though. I think it's a great post, and I'm thankful for all the wisdom to be found here. I just want people to beware when getting a foreign made block and dumping a lot of cash into a build, only to find that the base could have been junk. Much like a house where the foundation guy cut all the corners he could and all his errors are buried in the ground, only to show their face later in life.
 
All very true.

Sadly almost everything you buy any more is made in China.

I picked up a bunch of small parts for the DaHooooley build from the Ma General store.

On the OEM GM package is the part # tags with all the batch numbers and such stuff and it says to the effect (Always use genuine GM Parts) Hmmmm in the real fine print on the package it also says MADE IN CHINA

A neighbor of mine bought one of those little Chinese made tractors for her little horsie operation. That thing is the biggest POS I have ever seen.

It looks great, until you get into its innards.

Crude, crude, crude.

The rear ring and pinion failed. The stuff that came out looked horrible with the gears looking like cast iron rather than good steel.

Any more, I dont know what to trust. Not much anyway.


Missy
 
Whats so great about the AMG blocks? I know they are supposed to be stronger. Can you build them up like a dmax or cummins?
 
Michaeljp86 said:
Whats so great about the AMG blocks?
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Different metalurgy that improves the block material stength.

The block are supposed to have thicker main webs, thicker fire deck, steel main caps, etc.

The heads were given a redesign to deal with the cracking issues between valve seats. There was also supposedly a minor bit of cooling passage work to help deal with the valve seat cracking.

Some reading materials:

http://www.enginebuildermag.com/Article/1458/the_optimizer_6500.aspx

http://www.shotpeener.com/library/pdf/2003012.pdf

Michaeljp86 said:
I know they are supposed to be stronger.
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Yup, than an "original" GM design that is....

Michaeljp86 said:
Can you build them up like a dmax or cummins?
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Nope, it's still an IDI 6.5 with all it's design limitations for power production and heat rejection. You can pump it up a bit more than stock levels which is primarily limited by the injection system and the IDI design.

Even so, an AMG block that's not a P400 (rated some where around 440hp/550ftlbs but it's a different short block assembly than the Optimizer) is not going to hold sustained 500+ hp levels before it begins to run into troubles.....
 
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The AMG block (NON P400) that was meant for the Optimizer 6500 production has slightly thicker main webs, a much thicker deck, higher moly content in the cast iron and several other improvements is the best block going.

Again as mentioned, its not a Cummins or a Dmax.

You can easily make 300 HP and keep it alive for a long time.

With good AMG heads the cracking between the valves is not so much an issue either as the castings are heavier and better metalurgy.

Installing a Scat crank or if your well $$$$$$ a forged unit from AMG/GEP is the way to go.

With a super power chip, add a better turbo with an after cooler and maybe a water mist system, you can take these into the 350 HP range IF you are careful and watch the gauges and the coolant temps.

HEAT kills these things and fast.

A top flight cooling system along with a really good after-cooler can help a bunch

If you want 600 +++ HP then a Dmax is where your going to find it.

The P400 has the full bottom end girdle assembly that incorporates all 5 main caps into one huge casting. This along with the forged crank will keep them together well.

Still the limit is the ability of the engine to breath and not choke on the exhaust gasses.

The turbo is the limiting factor. The stock type turbo housings have a serious flow issue and they choke on the exhaust as it leaves the turbo and the drive side pressure heads through the roof seriously raising the EGT's

With a huge cooling system (BOAT) these engines can produce 400HP easily. In a pickup/Burban the limit is about 300 hp as the ability of the cooling system to reject the heat is just not there.

With a DS4 injection system, a good power chip, 4 inch exhaust and everything right up to snuff an honest 300HP is very doable with a 6.5 and see it live a good long time.

Also required is a keen eye on the boost gauge and the pyro.

Boost levels of around 12-14 PSI and EGT's of no more than 1000F Pre turbo or around 900RF Post turbo.

Run the engine with care and it will live a LOOOOOOOOOOOONG time at this power level.

Now if you don't want to watch the gauges, but instead run the crap out of it. Its a crap shoot.


Missy
 
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great white said:
Different metalurgy that improves the block material stength.

The block are supposed to have thicker main webs, thicker fire deck, steel main caps, etc.

The heads were given a redesign to deal with the cracking issues between valve seats. There was also supposedly a minor bit of cooling passage work to help deal with the valve seat cracking.Some reading materials:

http://www.enginebuildermag.com/Article/1458/the_optimizer_6500.aspx

http://www.shotpeener.com/library/pdf/2003012.pdf



Yup, than an "original" GM design that is....



Nope, it's still an IDI 6.5 with all it's design limitations for power production and heat rejection. You can pump it up a bit more than stock levels which is primarily limited by the injection system and the IDI design.

Even so, an AMG block that's not a P400 (rated some where around 440hp/550ftlbs but it's a different short block assembly than the Optimizer) is not going to hold sustained 500+ hp levels before it begins to run into troubles.....
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Boy you guys believe a lot because they say so.Without proof (show me the Nickel!)Chemical composition of the OEM and AMG block),thicker main webs(there is no friggin room without reworking the crank) a couple thou aint make a diff.:rolleyes5:
 
bison said:
Boy you guys believe a lot because they say so.Without proof (show me the Nickel!)Chemical composition of the OEM and AMG block),thicker main webs(there is no friggin room without reworking the crank) a couple thou aint make a diff.:rolleyes5:
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I thought back when these hit ebay that they did use a different crank.
 
There are several differences...

I have both a GM "506" casting / long block and my "optimizer 6500.. which is a Navistar / International 506 casting" (that I have been putting together for my truck, and have many pics of in my thread).
There is quite a difference in the 2 blocks and I can tell you this. I wouldn't even consider using a junk GM block or a Chinese "mystery metal" block. Hell the difference could be felt hoisting long block vs. long block AMG / GM from a cherry picker, as in you could tell the AMG block was slightly heavier. Like I already have said, Ted's has many Optimizer blocks and heads, if they come off those for rebuildable cores.. it would be foolish to even consider anything else be it GM or asian descent.

As was stated, the heads are definitely beefier, the fire deck of the block is beefier, the mains are beefier, nodular iron crank, forged rods, larger "diamond" pre-cups that reduce the compression to 20.3 : 1.. Over all a way better block / heads then any GM 6.2 or 6.5

The next best thing would be the P400, unless.... Dart were to cast a 6.5 block and some DI heads... maybe a lil wishful thinking there.

I am gonna try to push the limits a bit once mine is done and running, first with an HX35 and then with a HE351VE
 
I'm happy with the original Detroit Diesel design and the inherent limitations (thanks to GM). It keeps things in perspective and keeps me out of trouble. ;)

It is what it is folks.
 
OK Guys here is the real deal.

There were two direct inject engines built some years ago.

AMG is working on a common rail set of heads and will be testing them on one of the original blocks.

SOOOOOOOOOO, don't be supprised if a direct inject engine becomes available.

The sources tell me that this setup is slated to be installed on the P400 sometime in the future in order to get a leg up on the emissions garbage.

So basically, a P400 with direct inject pistons and common rail heads.

What sort of controls will be needed to run the thing?????? For sure your not going to use your standard 6.5 ECM and goodies to run it.

These engines will likely be used in some future vehicle Production. (HMMWV maybe)

Now, the crank webs in the AMG engine will allow the GM cranks, Scat cranks, or AMG Forged units.

The clearance between the crank wheels and the main webs is TIGHT, REEEEEEEEEEEEEEEEEAL tight at around .040" (40 thou)

You damned well better have proper main thrust or its gonna get UGLY.

Missy
 
great white said:
Because it would require a completely new injection system, new fuel system, new engine management system, new pistons, etc etc etc......

Be cheaper to just swap in a duramax/cummins and be done with it.

Whats the reason for a indirect injection? I cant really thing of any reason other then to keep the injector out of the heat when the fuel burns.

Or, just by a Duramax truck.....
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Missy Good Wench said:
OK Guys here is the real deal.

There were two direct inject engines built some years ago.

AMG is working on a common rail set of heads and will be testing them on one of the original blocks.

SOOOOOOOOOO, don't be supprised if a direct inject engine becomes available.

The sources tell me that this setup is slated to be installed on the P400 sometime in the future in order to get a leg up on the emissions garbage.

So basically, a P400 with direct inject pistons and common rail heads.

What sort of controls will be needed to run the thing?????? For sure your not going to use your standard 6.5 ECM and goodies to run it.

These engines will likely be used in some future vehicle Production. (HMMWV maybe)

Now, the crank webs in the AMG engine will allow the GM cranks, Scat cranks, or AMG Forged units.

The clearance between the crank wheels and the main webs is TIGHT, REEEEEEEEEEEEEEEEEAL tight at around .040" (40 thou)

You damned well better have proper main thrust or its gonna get UGLY.

Missy
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How would this direct injected 6.5 compare to a dmax or cummins?
 
Michaeljp86 said:
How would this direct injected 6.5 compare to a dmax or cummins?
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It won't, I don't think. You forget that the IDI nature of the 6.5 isn't the only power-limiting factor. Even with the factory girdle option, I'd guess that it's still going to be weak compared to the bottom end of a cummins or duramax. Have you checked out the bottom end on those two blocks and then compared it to a 6.5?
 
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