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NAGTROC,

We just finished the teardown of the VR38. At this point, we have the motor down to its bare bones. As soon as Jon gets a chance, he'll upload the remaining pictures of the shortblock rotating assembly removed from the block and I'll post them up. A lot more pictures yet to come!

As soon as we have the VR38 up on the Sunnen, I'll update the thread with all of the machining pictures. Then on to assembly of Glenns godzilla!

Enjoy the pictures of your venerable VR38 in its rawest form
























































Finishing the Crankshaft profile balance







Puuuuuuuuuuuuuuuuuuuuurfect!



















 

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wow.. chains for all the gears up there.. Haven't seen that in a while.. Look forward to seeing what you come up with for the build. I might be next
... This going to be a sleeveing, pistons and rods build?
 

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More pics added. More to come.

wow.. chains for all the gears up there.. Haven't seen that in a while.. Look forward to seeing what you come up with for the build. I might be next
... This going to be a sleeveing, pistons and rods build?
Nissan does love timing chains. We'll be using Carillo rods. Pistons are being evaluated and will be custom. Not 100% committed to anything else just yet. Still looking into other components. If you'd like, we can machine your block while were set-up for this one!
 

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Thanks for the pics AAM!
What is the HP goal for this block?
 

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Iirc mines is working on some cams. So is annother tuner in japan I forget the name. Also jun auto is working on some items due soon. I have yet to email them to get the scoop.

I think that the iron liners that were sprayed on should be removed and resprayed with a better alternative as suggested by the cosworth engine builder who created this engine "wink". He also suggested not a good idea to bore them larger due to the likely hood of water leaking through cracks because its too thin to begin with.
 

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Iirc mines is working on some cams. So is annother tuner in japan I forget the name. Also jun auto is working on some items due soon. I have yet to email them to get the scoop.

I think that the iron liners that were sprayed on should be removed and resprayed with a better alternative as suggested by the cosworth engine builder who created this engine "wink". He also suggested not a good idea to bore them larger due to the likely hood of water leaking through cracks because its too thin to begin with.
so sleeve it and then coat it with something better? or just sleeve it and call it a day
 

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Sleeving with iron liners is the way. You will not coat those bores with iron/material as good as stock. That is an extremely controlled process, prone to mistakes and misapplication; and giving a REAL thickness of iron...by that time, you would just sleeve it. I don't know of people doing "aftermarket plasma iron spray jobs"...
Darton makes iron sleeves for VR35/the 350Z engine...the VR38 is different, aluminum and thin bored, but it is ~inevitable that someone will do it and sleeves become available...
 

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Sleeving with iron liners is the way. You will not coat those bores with iron/material as good as stock. That is an extremely controlled process, prone to mistakes and misapplication; and giving a REAL thickness of iron...by that time, you would just sleeve it. I don't know of people doing "aftermarket plasma iron spray jobs"...
Darton makes iron sleeves for VR35/the 350Z engine...the VR38 is different, aluminum and thin bored, but it is ~inevitable that someone will do it and sleeves become available...
The OEM plasma coating is marginal at best. The limits have been found.

There are other coating materials out there better suited for the application.

Liners and sleeves aren't the only option.
 

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Xwing please refer to the link I posted.
Here is a direct quote. The context isn't there so u may need to read previous comments...

MeLLoN Stu, where did you get you information from? Are you a qualified mechanical engineer?

Nikasil spray coating which is on bikes, F1, etc is what you are describing, and is a trademarked electrodeposited oleophilic nickel matrix silicium carbide coating for engine components, mainly piston engine cylinder liners. It was introduced by Mahle in 1967. It is basically bullet proof expect when in the presence of high sulphur fuel (>350ppm), as the sulphur has a higher affinity for silicon than nickel - Jag and BMW suffered this in certain high suplhur markets, but most 1st world markets are now down at <50ppm sulphur level. We recommended to Nissan to go this route, but it does have some environmental issues during manufacturing, and people are still nervous after what happened to Jag and BMW.

There are virtually no applications that use plasma coating in racing or otherwise as Nikasil is so easy to do and is extremely robust. The GTR uses a plamsa sprayed iron coating, almost certainly applied using the Ford PTWA process (at least the blocks we did were). If it is applied using this process then it is probably the first ever application using the PTWA method in production (there are other methods such as Plasma from Sulzer Metco, but most still consider it not robust enough yet). Cleanliness of the parent bore before application of the iron is absolutely key, and it does not bond well if there are any problems. Also, when pushed too hard it will peel small strips of iron off (the coating is pretty damn thin), normally at the top ring reversal point, or higher if the edge of the crown contacts the bore.

"Plasma coating generally has a much lower coefficient of friction compared to cast iron".....probably not much different as it is also iron, "and has substantially better wear characteristics", not really again as is the same stuff expect thinner, "so I'll be interested to see what the piston rings are composed of"...the same ring pack and piston coatings are used as a standatd engine. Actually, for the GTR, the rings had a very tough time so the top ring has a better than PDV coating (can't remember is name, but could find out), with a positive twist too! The plasma spray effectively gives parent bore which is mainly done to improve heat transfer characteristics and save weight.

We had failures during development but we did bore them out and re-sleeve with iron liners (2mm thick). However, our blocks were originally designed to take 2mm iron liners, and thus the aluminium thickness to the water jacket was 6.5mm nominally when parent bore....with the liners fitted this obviously becomes 4.5mm of AL and 2mm of iron between the outside of the cylinder and the water jacket. For a fully optimised parent bore solution (to improve heat transfer) the water jacket should be moved in 2mm so it becomes 4.5mm from the outside of the cylinder to the water jacket....this means that fitting liners would be pretty much impossible without damaging the water jacket in some way (pressing the liners in would probably crack the wall that is left between liner and water jacket, leading to internal water leaks....the water will find it's way out).

Distance between cylinders (bore spacing) is not a problem even though it has siamesed bores (no water between bores), although there is probably a cross drilling between bores. Parent bore does enable engine to be made smaller, but for a 60 deg V6 the benefits are marginal as the engine geometry is always governed by the fact that you need a flying web on the crankshaft between opposite cylinders to maintain even firing.
 

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Great pics of Godzilla's heart! Looking forward to the post-heart surgery pics.
 

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i just drove Georges car and dont want to steal his thunder but it was one of the most increadable cars i have ever drive in... WOW!!!
After he puts about 1000 miles on it he will be back and start posting... its frickin insane
 

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The OEM plasma coating is marginal at best. The limits have been found.

There are other coating materials out there better suited for the application.

Liners and sleeves aren't the only option.
However, since there are probably a millions of cars out there with sleeved motors without any type of coating and no ill effects, the whole "keep it simple stupid" comes to mind. I am sure that is what Xwing is getting at. I am sure you know things can, and often do, go wrong when get into a build of this caliber, so there is somthing to be said for eliminating potential snafus.
 

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Better get your orders in for bearings and engine overhaul kits. Nissan is tight as clamshell about those parts.
 

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However, since there are probably a millions of cars out there with sleeved motors without any type of coating and no ill effects, the whole "keep it simple stupid" comes to mind. I am sure that is what Xwing is getting at. I am sure you know things can, and often do, go wrong when get into a build of this caliber, so there is somthing to be said for eliminating potential snafus.
I agree. Keeping it simple is the best solution. Especially for a motor which has not had any catastrophic damage or wear from mileage. Sleeves will be available in the future - this is something I know first hand. However, just like with any other motor, sleeving is a very specialized process - a process which benefits from specialized machines and someone with A LOT of experience. Sleeving is something we pride our selves in - however, in this particular case, sleeving is not the simplest nor most efficient route.

Without cylinder wall wear or catastrophic engine failure, we don't see the need to cut and re-sleeve the closed deck vr38 (On an open deck block I understand and see the reasons). In this particular case, we will be using a couple of tools for our CNC SV-10 hone developed for ever-so-slightly cutting and resurfacing ceramic liners (as well as other materials) like that found on the GT-R. After the cut & hone is complete, we will take measurements and order pistons. They'll be an odd size - but perfectly suited for the cylinders.

(edit: being a little more specific)
 

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I agree. Keeping it simple is the best solution. Especially for a motor which has not had any catastrophic damage or wear from mileage. Sleeves will be available in the future - this is something I know first hand. However, just like with any other motor, sleeving is a very specialized process - a process which benefits from specialized machines and someone with A LOT of experience. Sleeving is something we pride our selves in - however, in this particular case, sleeving is not the simplest nor most efficient route.

Without cylinder wall wear or catastrophic engine failure, we don't see the need to cut and re-sleeve the closed deck vr38 (On an open deck block I understand and see the reasons). In this particular case, we will be using a couple of tools for our CNC SV-10 hone developed for ever-so-slightly cutting and resurfacing ceramic liners (as well as other materials) like that found on the GT-R. After the cut & hone is complete, we will take measurements and order pistons. They'll be an odd size - but perfectly suited for the cylinders.

(edit: being a little more specific)
so your saying thats suffice enough to just do that then drop a set of custom sized forged pistons in and call it a day? No liner needed, just get rid of the plasma coating and what not?
 
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