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question re: custom forged crankshafts and cylinder liners...


Mack

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so, who makes nice custom crankshafts? I was looking at scat and they charge about $1100 for a forged crankshaft for chevy smallblocks, so I would imagine L6 would be comparable, yes? I am contemplating a custom stroke cranky....

 

also, whata bout cylinder liners? who sells em? looking for liners for an LD28 block... evil ideas about in this post....

 

Mack

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so' date=' who makes nice custom crankshafts? I was looking at scat and they charge about $1100 for a forged crankshaft for chevy smallblocks, so I would imagine L6 would be comparable, yes? I am contemplating a custom stroke cranky....

 

also, whata bout cylinder liners? who sells em? looking for liners for an LD28 block... evil ideas about in this post....

 

Mack[/quote']

 

Scat will do a Z Car crank. It will be a billet unit. Price runs about $1700-2200 depending on how far you want to develop the part. (knife edging, etc.)

 

Moldex is another place that did them in the old days. Pricing is about the same.

 

Crower did list a stroker billet unit a few years back. You might give their tech department a call to see if they have some old stock left, or the machine program to make a new run.

 

As far as a forged unit goes you will be looking at remanufactered stock units.

 

Liners should be listed in a machinsts catalog for boring stuff. If you want to do something exotic like that maybe you should look into how far the diesel block can be bored. It has a real tall deck and could take a 85-86mm stroke. Maybe a bit more. Look at the stroke for the L20b - LZ blocks as those have 20mm more deck height.

 

At some point the head air flow restriction will catch up to your cylinder volume.

 

Alan

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DrSideWays, get outta my head! lol, the deisel block is exactly what I was thinking about using, seeing as how I bought the whole block for the cranka while back. I was contemplating building a Long Rod stroker motor.

 

I was looking at a 90mm x 90mm motor. it would work out to be about 3.45L. The Diesel block is the only way you could mantain a decent rod/stroke ratio. I figure I could use 4 cyl rods, like Z20S or L20B and I wouldnt be too bad off. the deisel block already has liners, so it would just be a matter of taking the old one out and pressing a new one in. Tony D is always talking about having a ride in L series 3.3 and 3.5 motors, so it got me thinking. I wonder if you could have a stock deisel crank re-worked that far tho....

 

Mack

 

P.s. on the head part, Ive got a few tricks up my sleeve.... :D A freind of mines father owns a machine shop, with a flow bench, he has ported a few P90's to flow about 205cfm intake and about 155cfm exhaust @ 25 in of water.

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...the deisel block already has liners, so it would just be a matter of taking the old one out and pressing a new one in.

 

What makes you think the LD28 (diesel) block has cylinder liners?

 

 

I have disassembled five LD28 engines (to get the crank) and I have never seen any liners.

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I did not mean for my post to start an argument, Mack.

 

I was referring to the early LD28 engine used in the 1981-84 Maxima, not the later ones used in several (mainly international) applications and not the “industrial” version shown in the above web site.

 

I do not think you have be an expert diesel mechanic in order to make a simple observation about these engines.

 

Cylinder liners are (or were) available for the early LD28 block but these are for service reconditioning of a worn block.

 

I conclude that sometime during the long production run of the LD28 engine Nissan probably started installing cylinder liners at the factory.

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Liners or no liners, somebody should kill a block to see how far it can be bored. At 84.5mm it would seem to be a stretch to make it out to 90mm. Even with a liner it would have to have some of the block to slide into.

 

It could well be that the bore castings could take a large bore like a LZ configuration in a gas application. The best way would be to get a block and have at it.

 

I have seen a turbo LD28 in a Z Car. It seems to be a tight fit for the hood. You can slot the engine mounts at the block and let it slide down a bit for clearance.

 

It sure would make for a nice torque motor. With a 5 1/4" clutch setup and FI you could get some revs out of it.

 

Get one and do some research.

 

Alan

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Guest MCTomTom

I know a guy who took a crank out of an old diesel maxima, fast as hell, but if you would want to look for a similar kit, there is a kit on motorsportauto.com which gives you stroker crank, pistons, rings, and pins for about $1800 I think. Pretty good deal for all the stuff it gives you.

 

MCTT

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I know a guy who took a crank out of an old diesel maxima' date=' fast as hell, but if you would want to look for a similar kit, there is a kit on motorsportauto.com which gives you stroker crank, pistons, rings, and pins for about $1800 I think. Pretty good deal for all the stuff it gives you.

 

MCTT[/quote']

 

naw.... your kidding.... :-D

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Guest Keith240

.. Hey guys - new to this list, I am...

 

I have an LD28 diesel in my 280Z right now. It's an nice fit, but it also is a stock diesel LD28 ... so it still fits like it should in a Z car - I'm aware of the slight hight difference with the gas engine head mentioned previously. I also have a complete 1983 Diesel Maxima car for parts, and am planning on using this engine in my current 240 project. The LD28 block, crank, rods - and - VG30 DETT pistons - w/ a P90 head - I'm willing to try this new combo. in my project 240Z. I haven't started on it just yet as the diesel car is still in the wild and I need to pull the engine/trans, plus it's snowing right now. I see that the LD28 rod/stroke ratio is a perfect 1.8/1 as it comes from the factory. So, I want to try to mix VG30 pistons with the LD parts, and as such, I'll find out in a few months just how far you can safely bore the LD block. If I'm correct then the pin hight of the VG pistons and the rod length of the LD will work together with the LD crank, and I'll double check that math on Monday and report back. I've been wrong before ( and admit it ahead of time ) so please don't hold it against me if I am. I have several DETT pistons in hand and want to use these if possible instead of going to CV products to buy the more conventional forged KA24DE pistons to use with L24 rods - and end up with the not so nice 1.6/1 rod/stroke ratio.

 

Any comments or suggestions are welcome - I'm looking for advice as well as willing to share my findings with you.

 

Keith 240

 

finished '71 510

project '72 240Z

finished '77 LD powered 280Z ( 40 mpg! )

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actually, you;lll have to use a different rod if your planning on using the LD28 block and a VG piston. the LD rod is 140mm center to center, the piston has something like a 44mm compression height. best combo Ive run acroos would be KA24E pistons on a Z22E( I think ) rod and an LD28 block/crank. the LD28 block has a deck height of 227.5mm vs the L28E blocks beck height of 207.9mm.

 

McAdam

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Guys, realize that the LD engine used later has DRY liners. This means you aren't cutting into the water jackets. I would bet an LD could be bored SIGNIFICANTLY and run on the block iron just fine.

As for the "Diesel Liners" used in the HKS 3.5 and 3.3 conversions, I never said I clarified from the Japanese guy that they were from a Nissan.

In the day, it wasn't uncommon to cut to the water jacket, and push in a diesel liner to an L20A to make the bore similar to an L24, and with the L24 crank you had a nice little 300HP sleeper that has "L20A" for Japanese Inspection and anyone who might like to match race you...

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  • 4 years later...

I know the triumph motors we rebuild come with liners and you can't find them anymore from triumph or moss so when we do crazy stuff or when they need replacing we find ourselves taking a trip to a tractor shop. >_>

 

Then again those motors are tractor engines but I mean, its a source of liners yah?

 

I don't see why you wouldn't use an F54 block, bore it out until you hit water and then sleeve it. With a shop discount, I may snab a junk yard block and do that! They say 3mm thickness of material is the limit to being safe on the cylinders so if you bore that thing out and get real nutso, use the F54 block to avoid height and conversion issues. My you have a sexy combination.

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The IH isn't an LD28, but an SD series motor. The crank wouldn't work in an L series motor. Also, this thread is pretty old but it is good to see I'm not the only one who has schemed and plotted the 90 x 90 idea.

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Thinking on it some more, the real limit for boring would be the cylinder stud spacing. And don't the LD's have larger studs than the Petrol Engines? Tehcnically that would mean the bore of an LD would be limited slightly moreso compared to a Petrol Engine with the smaller head stud diameter.

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Ok, you cannot bore out all the cylinders and install sleeves in all of the bores. The only way you can do this, is if you weld the sleeves to the top of the block, and to the lower end of the block. If you dont, there is no strength left in the block, and it will flex and break. Rule of thumb, is you cant sleeve to bores next to eachother without welding. And no, you cant just break out your mig welder and weld them in, lol.

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