'70 Nova LSX swap LY6/TH400

[TheBandit]

Okay stupid question, but would an engraver be an acceptable alternative to a scribe?

[entropy]

Originally Posted by TheBandit

Okay stupid question, but would an engraver be an acceptable alternative to a scribe?

In my opinion anything that disturbs the surface of a PMR INCLUDING a scribe is a No-No! Use ink or paint.

Been doing some research on these things and all the hype is good but when you go beyond the glossy magazines things get a bit less positive.
I will grant that PM has come a long way but it still holds true that much like stressed CF one flaw can revert it to its prior state. That scenario I have witnessed PooF a pile of powder where a part had been!

I would not worry about marking rod and cap because there is, other then at assembly, virtually no time that cap should be off a cracked rod. Yes, you do need some type of rod vice to keep things aligned and you never want to misalign these silly things; however you do not need to retorque these off the crank so you are good without the vice.
Basically this (PM) is another one of those developments that takes cost out of the engine without really improving the final product; PM has improved but really needs more development years before PMR is an improvement over the part they replace in any sense other then reduced cost to the manufacturer.

Seriously I would just felt-pen the piston tops; I would in this case just put the R&C back togeather finger tight on the bench and clean the rust then immediately reassemble. When I resembled, I would pop the bearing shell out, clean the rod and bearing with BrakeClean make sure there was no contaminates between them, do the same with the cap and then lube with Redline assembly lube. Follow the factory spec on bolt prep and torquing, using the stock original bolts unless GM says otherwise.

E

[TheBandit]

Okay e, you've convinced me. I've just got to be very careful not to lose the markings I put on these.

The teardown continues. First I used a very small amount of brake clean, a nylon brush and towels to clean the piston tops, bringing companion cylinders to TDC prior to cleaning. Then I marked each piston top with black sharpie.



Next I rotated the engine over on the stand and one by-one removed the piston-rod assemblies. After loosening a pair of rod bolts, I tapped on their ends to separate the caps from the rods. In this picture you can see one of the unique fracture interfaces.



Because there was no ridge whatsoever at the tops of the bores, I was able to push the pistons out by hand and catch them on the other side.



Below is what a typical rod journal looked like just after cap removal. They were all wet with an oil-water-rust mixture, but for the most part the journals looked good where the rod bearings contacted. But there are lines of rust going around between the two rods on each journal. None of the bearings or journals show signs of scuffing or scratching.



I did make several concerning observations going through this. Please let me know what you think. First, the #7 rod had a considerable amount of rust on the thrust surface.



Next, I found two rod bearings with some black discoloration like this one. I'm not sure if it's pitted or just discolored.



Finally, there was some concerning rust on either side of the bottom of this cylinder bore.





Here's what things looked like with all the pistons out.



I carefully laid all the piston-rod assemblies into this plastic container, adding some backup markings on the bottoms of the pistons with sharpie. These all need to be cleaned and de-rusted.



That's as far as I got tonight. Back in the bag!



This is the first crank I've spun over without pistons & rods attached. It sure turns buttery smooth without all that friction. Kinda neat taking this thing apart, but I'm not looking forward to the cleaning process.

What do you guys think?

[entropy]

...if it was mine I would take it to a shop, have it cleaned, honed, polished, new bearings/rings...

[sniperperformance]

Originally Posted by TheBandit

Okay stupid question, but would an engraver be an acceptable alternative to a scribe?

this is what i do for a living. the answer is yes. you want to lightly engrave them. just enough to see. if you write on them with anything chances are there righting will come while cleaned. then your in a world of hurt beings how they use fracture cap technology on them. you will never get them right again.

[sniperperformance]

Originally Posted by entropy

...if it was mine I would take it to a shop, have it cleaned, honed, polished, new bearings/rings...

x2 im with E

[JaysinSpaceman]

Looking at what you got there I would have to agree with E, light polish on the crank and a very light hone in the cylinders.

I find it hard to believe that you got that much water in the engine washing it. From the rust between the rod bearing and crank I would say that it was either run or at the very least turned over several times after it had the water in it. Turned over enough to pump the water into the bearings. The reason I say this is because I have taken apart engines that sat with rain water in them for years and there wasn't any rust between the crank and bearings because the surface tension of the oil holds the water out. Do you know if it was spun at all after your wash job? If not it probably had water in it before you got it.

Jaysin

[TheBandit]

I have spun it over by hand a few times since washing, but not much. Prior to washing, I turned it over with the starter to do a compression check. It was around 180psi on all cylinders. I did not notice any water in the oil when I drained the little bit that remained from when the engine arrived.

Thanks for the continued advise.

[TheBandit]

Originally Posted by entropy

...if it was mine I would take it to a shop, have it cleaned, honed, polished, new bearings/rings...

I need to find a trustworthy machine shop around here. Having the bottom end apart has me thinking about build possibilities. What's a few grand here and there to put a smile on my face? I've priced out a stroker rotating assembly: Callies Compstar forged 4" stroke crank, Callies compstar forged H beam rods w/ ARP 2000s, and Wiseco pistons with rings and pins would set me back about $2,500 including a set of bearings and balancing. That would give me a nice bump in cubes (364 vs 402) and compression (9.6 vs 10.6)

I'm not sure what it would cost to hone the mains if I put ARP studs in. Also not sure what it would cost to get the block cleaned, R&R cam bearings, hone the bores, and perhaps resurface the decks. Any ideas?

I put a shopping cart together and including all the stroker parts, gaskets, ARP head bolts, ARP main studs, LS7 lifters, I'm up to about $3,100 in parts alone. Ouch.

[entropy]

...just call Turnkey (or =) order the complete package drop it in turn the key...

I've built a few high output engines over the years and there is just no way most people are going to compete $/HP with a brand specific build house.
Be sure to tell them it has to run on 89

[TheBandit]

I've thought about that route too. Still have a lot of homework to do. I'm also thinking about staying with the stock crank and upgrading rods and pistons. Not worth a ton of power but good peace of mind. Or I can do the bare minimum and end up where I started. So depressing.

[entropy]

Originally Posted by TheBandit

I've thought about that route too. Still have a lot of homework to do. I'm also thinking about staying with the stock crank and upgrading rods and pistons. Not worth a ton of power but good peace of mind. Or I can do the bare minimum and end up where I started. So depressing.

Kant have that!
I'll post a fresh engine story over in the lounge here in a few...

[TheBandit]

Okay, I'm looking forward to it!

Found this article with some quoted costs for machine work: http://www.carcraft.com/techarticles...d/viewall.html

Clean and Magnaflux $88.00
Bore and torque plate hone $224.00
Deck block $150.00
Balance rotating assembly $198.00
Install cam bearings $44.00

They didn't hone the mains on that build. Total cost for above: $704. I don't think it matters how I crunch these numbers - my wife is not going to like this idea!

[JaysinSpaceman]

As for the main tunnel hone, if you are just going to ARP bolts and not swapping to main studs there really isn't a reason to hone the main tunnel. As a side note, unless a block really needs line honing the main tunnel it is the last thing you really want to do and here's why... Since they don't make main bearings with a larger OD you have to grind the main caps and then remove material from both the cap and block to make the hole round and the right size again. And in doing this you effectively move the crank up in the block, not by much but I can always tell when a block has been line honed because a brand new timing chain will go on feeling loose with slack like a used one. This will give you greater slack in the timing chain and therefore less control over cam timing.

Jaysin

[TheBandit]

Thanks Jaysin, that's a good point. ARP doesn't make main bolts from LSxs (I don't think?), only studs. The factory fasteners are stamped 10.9. I'm not really sure ARPs are necessary here - I think they're more important on the rods than anywhere else, but I'd still like to know what it would cost to put them in. The studs by themselves are over $200.

[sniperperformance]

i know im new on this forum. but this is in my field of expertise as fabing is in yours. the crank can handle 800-1000hp depending on your tune/tuner. the rods if you have the cash i would replace for sure as they are the main weak link in all ls based engines.

the pistons would be my next thing to replace the sides skirts are known to ware heavy even though alot of them have a anti friction coating on them. of couse replace all the bolts you can with ARP bolts as the torque to yeild bolts are a pain and need to be replaced everytime you have to remove them.

ARP dose make main bolts for ls engine but you have to call them. in my twin turbo ls engine i used studs everywhere but i dont think your going to push the numbers i am.

k1 tech rods are good rod and very affordable i used them in mine and have hit them with more than 7000rpms and 28psi of boost and i know they will take more. they run about $500 - $600 for a billit h-beam rod with good ARP2000 rod bolts. the price is for a set.

alittle word of advise. if you are going to upgrade the rods and pistons i would order 6.125 legth rod and pistons to match. and your rod ratio will be better along with a much more durable rotating assembly after balancing.

hope this helps

most basic machining runs from $450-$650 unitl you get into main line honing decking or blue printing. honestly as long as you stick with main bolts you dont need the main line honed. and vould avoid it if you can. decking is always a good idea.

[entropy]

Originally Posted by sniperperformance

i know im new on this forum. but this is in my field of expertise as fabing is in yours.

Since you are more versed in the LS then I, what would "you" say is the power/RPM limit to the PMR as delivered from the factory?

Admittedly I have little hands on with this Ford derived engine design


Can we hijack this thread

[sniperperformance]

Originally Posted by entropy

Since you are more versed in the LS then I, what would "you" say is the power/RPM limit to the PMR as delivered from the factory?

Admittedly I have little hands on with this Ford derived engine design


Can we hijack this thread

well the rods are the 1st to hold you back and i wouldn't test them past 600hp. or 6200rpm. im more of a durability guy. when i build something i want it to run problem free 10 years from now. powder rods after enough heat cycles tend to grow weak. which lower the hp rating. so above anything else i would say those have to go. ford guy huh E, i have alittle exsperiance in those to 5 years worth at rousch racing. i a big power sports fan in my book there all good when modified lol.

[entropy]

Originally Posted by sniperperformance

well the rods are the 1st to hold you back and i wouldn't test them past 600hp. or 6200rpm. im more of a durability guy. when i build something i want it to run problem free 10 years from now. powder rods after enough heat cycles tend to grow weak. which lower the hp rating. so above anything else i would say those have to go. ford guy huh E, i have alittle exsperiance in those to 5 years worth at rousch racing. i a big power sports fan in my book there all good when modified lol.

Endurance is also where I come from a few years back though most would not know the name, one of the shop sponsored was a TwinTurbo Gen5 made silly power levels and for literally hours at a time, boats and aircraft, particularly the latter are not allowed to fail.
As for brand... I've built more GM then any other and I agree they are all ok, and if we can make them faster so much the better!
It is just so easy to raz the Goat Mechanic fans.

[sniperperformance]

Originally Posted by entropy

Endurance is also where I come from a few years back though most would not know the name, one of the shop sponsored was a TwinTurbo Gen5 made silly power levels and for literally hours at a time, boats and aircraft, particularly the latter are not allowed to fail.
As for brand... I've built more GM then any other and I agree they are all ok, and if we can make them faster so much the better!
It is just so easy to raz the Goat Mechanic fans.

i agree. i tend not to tell my hp numbers in my car becouse alot of people think its all fiction. but these turbo's brung a whole new game to the world of power. i 1st started out with a factory LQ4 block and cnc ported 317 heads and made 1034hp at 16psi boost. then started lifting my heads so i then went to a LSX block and sce head gaskets, with the built ring. and haven't had any issues since.

i had to help him out everyone been really kool to me on this site.