'70 Nova LSX swap LY6/TH400

[TheBandit]

Originally Posted by entropy

Long ago after i quit building star ship quantum drives
Things are so much easier in zero-G

I have no clue what you're talking about!

Originally Posted by entropy

Manely I have seen made it into recyclable material. Maybe they have improved!
The Eagle stuff while I expected the same; consistently delivered way beyond its supposed capability.
That is all.

That is interesting to hear. Eagle stuff is a lot cheaper.

Through the course of the last 12 hours I've just about done a 180. I'm ready to do the bare minimum to get this back together with fresh bearings and rings. If it doesn't work out (i.e. rod through the block or what-have-you), then I'll rethink and restrategize.

[entropy]

Originally Posted by TheBandit

I have no clue what you're talking about!

You should, but: Think of it as me not taking myself seriously.

Originally Posted by TheBandit

Through the course of the last 12 hours I've just about done a 180. I'm ready to do the bare minimum to get this back together with fresh bearings and rings. If it doesn't work out (i.e. rod through the block or what-have-you), then I'll rethink and restrategize.

I see you listed the design criteria for the outcome of the build, have you ever sat down and built to the design criteria on paper, then drilled it down to every nut and bolt? (I learned to buy fasteners by the box, the box saves time planning)
Most projects don't get completed or completed in a reasonable amount of time because there is a failure to execute to a realistic hard plan. Look at the number of Race cars that fail to make the big race, I can think of a dozen in U4 that didn't make KOH for example. So, is a mildly warmed up LS in the plan or is a refreshed stock one? Seems to me one is and one is not, and I completely understand daydreaming and it can be a productive tool or diversion. It can also lead off into quagmires of time and money that were never in the plan, delay completion, bust the budget, cause "what if" syndrome, the list goes on...
From the sounds of it you are not hung for the $$ so just pull the trigger on the options in your plan and get this thing on the road. From what I am reading that is going to make your spouse the happiest (better be in the plan) other then scrapping the entire money pit.

Of all the things I learned building star ship quantum drives, the plan its the most important, and the execution of that plan makes for sweet outcomes.
It's a Zen thing

[JaysinSpaceman]

Originally Posted by entropy

Most projects don't get completed or completed in a reasonable amount of time because there is a failure to execute to a realistic hard plan. Look at the number of Race cars that fail to make the big race, I can think of a dozen in U4 that didn't make KOH for example. So, is a mildly warmed up LS in the plan or is a refreshed stock one? Seems to me one is and one is not, and I completely understand daydreaming and it can be a productive tool or diversion. It can also lead off into quagmires of time and money that were never in the plan, delay completion, bust the budget, cause "what if" syndrome, the list goes on...

Bandit,

This is essentially what you said to me in my Toyota build thread. Scope Creep. The engine having problems wasn't in the plan, true, but neither was the whole rods, pistons, rebuilding the lower end, etc... so if it were me in your shoes I would get the motor back together with the least hassle (this doesn't necessarily mean the least $) and try to keep the whole thing more or less on your original plan. I see that as being the best way to accomplish your original goal in the least amount of time.

My $.02
Jaysin

[AngryBee]

Forgive me if I'm reading this incorrectly, but what's an extra $300 in the scheme of things for piece of mind? I'm not a piston man, but to me anything that will make the build stronger and less prone to failure in harsh conditions would be a good thing.

Tone

[TheBandit]

Alright, after waffling over this for a while, I've committed to a direction. I'm planning on reusing the stock rotating assembly with new bearings and rings, after a good clean, polish & light hone. I am trying to take a dose of my own advice and limit my scope just as Jaysin suggested (thanks for the nudge, btw). The original plan wasn't to upgrade any internals. I need to stick to that plan as best I can to conserve cash for other parts of the car.

Got an itch over the weekend and ordered a whole bunch of stuff from Summit.



Inside the box:
- ARP 134-3610 head bolts for 2004+ LSxs (all short)
- ARP 234-2503 balancer bolt for LSxs (except LS7s)
- Comp Cams 104 engine assembly lube
- Comp Cams 4758-2 checker springs
- Clevite CB663P rod bearings (x8, they are sold individually) std
- Clevite MS2199P main bearing set std
- GM 12499225 LS7 lifters (set)
- GM 12610046 MLS head gaskets (x2)

I also got a valve spring height micrometer, fixed 4.000 piston ring compressor, torque angle gage, and some plastigage . All in all about $600 in damage and some assumptions that the crank will not need to be ground and I can reuse my pistons.

I guess when you put enough of their kids through college, they send you a free hat. That was nice surprise, so here I am wearing it.



Now that these parts are here, I feel a bit more motivated to clean the rotating assembly and get the parts to the machine shop.

[TheBandit]

I finally managed to get started on parts cleaning. A few years ago the local hardware store was clearing out their inventory of Evaporust. I bought a gallon thinking I was probably wasting my money, but may as well have it around to try. I finally found a use for it - my rusty connecting rods!





Evaporust is a non-toxic, non corrosive, bio degradable waterbased product that to my surprise, works as advertised. It is what's called a "selective chelation" which bonds to iron molecules, pulling the iron from iron oxide, but isn't strong enough to pull the iron out of steel. There are a number of home-made rust removal solutions that work in the same manner, but this stuff is ready made and has a few other ingredients to help the process along (for example, surfactant to penetrate oils).

I cleaned the connecting rod above using brake cleaner, then let it soak overnight submerged in the Evaporust. The next day I rinsed it with a garden hose, immediately compressed air dried it, then sprayed it with WD40 to prevent any new rust. The results can be seen below comparing one rod I've cleaned and one I haven't.





Note, in the photo below there is a line below the small end of the cleaned rod. This is where I had left the small end exposed above the Evaporust bath, but later submerged the whole thing. I believe it to be cosmetic only.





I couldn't be happier with the results, so now I am going one by one cleaning the rods in this manner while being careful not to mix any of them up.

I wish a had a giant tank of this stuff I could lower the engine block into. Hopefully the machine shop can help with that problem!

[JaysinSpaceman]

Looks good Bandit. Just take your time and do it right "once". I've never used that Evap-o-rust before but it looks like it does the trick.

Interestingly enough you and your bandit emblem bear a striking resemblance.

Jaysin

[CarterKraft]

wow nice work on the rust removal, that stuff works great gonna have to remeber that stuff.

I would get the loupe out though and make sure that line on the small end is a surface film only as you know that would be a terrible place for a stress riser.

[TheBandit]

Originally Posted by JaysinSpaceman

Interestingly enough you and your bandit emblem bear a striking resemblance.

Originally Posted by CarterKraft

I would get the loupe out though and make sure that line on the small end is a surface film only as you know that would be a terrible place for a stress riser.

What is "loupe"? That line was right at the surface of the bath. At first I wasn't sure if I wanted to dunk the bushing into the stuff, but after reading up on how the rust remover worked, it I decided to go ahead. I'm confident it is merely a film/deposit and wont cause a stress riser. Of course if the no 8 rod gives up down the road, I will look back on this and wonder!

[CarterKraft]

its a poor mans microscope don't really need one I suppose I was just suggesting to study the line really close to make sure it's just a surface coating. that would be such a perfect riser it would be a awesome failure.

[TheBandit]

Gotcha! In the context I thought you were talking about some kind of cleaning agent or tool for removing the film/deposit.

I have access to a couple nice x-ray machines and an array of microscopes at work. Might be kinda fun to look at a rod or two.

[CarterKraft]

Nice!

In the past I would just move right past cosmetic items like that but after taking a failure analysis course several years back and seeing what a tiny little nothing turns into under maximum stress I started trying to pay closer attention to those things.

Of course on the engines I work on 90% of the time we impact the mains with a 3/4" gun, so for me to pay closer attention is probably a good thing.

[TheBandit]

I recently got a C6 Corvette drive by wire throttle pedal that an LS1tech forum friend sent me and decided to try mocking it up. I had seen where someone used one of the mounting screws around the steering colum as a convenient place to bolt this up on a 1st gen Camaro, so I cleared the plastics and insulation surrounding the area and gave the same mounting screw a try on my Nova. Turns out, it positions it fairly well.







You can see above where the pedal is mocked up with the lower bolt hole attaching to an existing location on the firewall next to the steering colum. This position isn't without problems. The firewall is not flat in the area to the right or above, so the mounting plate doesn't sit flat. The pedal is remarkably close to the original position though and is comfortable to operate. It reaches a mechanical stop built into the pedal about 1/2" before contact with the carpet. I think I may use this location, but I will need to come up with a more robust mounting.

Something that surprised me about the C6 pedal is that the pad is nearly identical in size and design to the original Nova pedal. In fact, I can not tell the plastic portion apart. I am going to try swapping the chrome bezel over because I think it will fit

[TheBandit]

I've also been working on cleaning up the original pistons. I decided to try soaking them in a mixture of Simple Green and water. *EDIT* DO NOT DO THIS. I LATER DISCOVERED SIMPLE GREEN EATS AWAY AT THE ALUMINUM AND THESE PISTONS WERE JUNKED*



They aren't cleaning up as quickly as the rods, but after about two weeks of soaking and brushing them every few days with a brass bristle brush, they are looking close to new again. Here is a cleaned piston next to one that hasn't been soaked or brushed yet (except for some cleaning I did to the top when it was in the shortblock still). All the pistons had a lot of carbon buildup around the top ring, both above and below it, which was very difficult to remove.













A few notes on these LY6 pistons. As you can see they are dished with two valve reliefs. The floating pins are retained with simple circular clips that I removed easily with a flat head screwdriver. The areas on either side of the top ring appear to be anodized (something I read are a feature on LS3 pistons). The skirts are coating. Unlike what I read about LS3 pistons, there are no cross drilled holes for washing oil from the cylinder walls down back through the piston.

After pulling them from the Simple Green solution, they started forming little chalk like spots which I think are oxidation. So I brushed that stuff back off and sprayed them with WD-40 which seems to keep it from happening.

And I started taking the heads apart in prep for cleanup and new springs. I'm thinking about taking them with me to the machine shop to have them cleaned, though I might just try the same Simple Green soak I'm doing on the pistons. I'm using a mechanical spring compressor I found in a clearance bin at Sears. It is self locking, but seems to twist a bit under load. I'm a bit worried it wont be up to the task of installing the new double springs.



The factory one piece valve seals plus seats came off easily with a twist and pull.



A long time ago I learned this trick for storing valves; just punch some holes into a box using a screwdriver and push them into place. A slight interferance holds them nicely.

[TheBandit]

I managed to finish disassembly on both heads tonight. They are now bare & ready for cleaning.



I decided to try my hand at checking valve spring height, so I pulled out my new Proform valvespring height micrometer and gave it on a shot on the #1 cylinder valves.



The height micrometer is very easy to use. The body is made of two halves that expand apart when rotated. You assemble it into the head in place of the valvespring, expanding it until the valve is fully seated. Graduations on the side tell you the height.

One thing I am a bit concerned with about this height micrometer is there's a step down at the top with an ID only about 1/16" smaller than the OD of the valve spring retainer. It felt like the retainer sort of self centered on this ID, which makes me think the retainer is sitting on the chamfered edged. This is how it's sitting in the above photo where I measured a height of about 1.8025in.

So next I tried offsetting the micrometer so at least half of it would be fully underneat the retainer. That's how it's sitting in the photo below where I measured a height of about 1.7975 - about a 0.005in difference.



I'm not entirely sure which of these numbers to trust, but I'm inclined to believe neither are anything to be concerned about. What do you think?

Here is the exhaust valve on the same cylinder with the micrometer centered on the retainer. I measured a height here of about 1.810.



Considering the spring rate of 469lb/in, a 0.010in difference in installed height would be a 4.7lb difference in seat pressure or about 3% of the closed pressure and 1% of the open pressure. This seems like it would be negligeable to me, but what do you think? I'm not really sure at what point I should start thinking about shims.

[entropy]

I doubt that the factory holds 0.005.
Check what shim thicknesses are available for these heads and don't worry about anything less then the thinnest shim that is recommended in single use.

[TheBandit]

It looks like the thinnest shims sold for these is 0.015in. I've read a typical acceptance range is around 0.025in from nominal. Something else I came across was recommending shimming the springs to 0.060in from coil bind (installed hieght = bind height + max lift + 0.060) - basically targeting the maximum seat pressures for a given spring while leaving 0.060 bind clearance. It seems to me like if the cam profile was designed around nominal spring pressures, I should shoot for those and just stick to the 1.800+/-0.025 range. Just sorta thinking out loud. What have you done in the past e?

I read something about Simple Green being bad to use on aluminum. That is a bit worrisome since I have my pistons soaking in the stuff. Here's what the Simple Green site says:

aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green All-Purpose Cleaner can accelerate the corrosion process. Therefore, contact times for unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green® product residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation.

10 mins.. hmm... my pistons have been soaking in Simple Green for as much as two weeks now. I wonder if I've done any serious damange. They don't look any different (except for being clean), but this would explain the chaulky oxidation I was seeing.

[JaysinSpaceman]

I would doubt that you have caused them any harm unless they came out with a white gritty coating (this would be excessive aluminum oxide) or have signs of pitting. Aluminum's natural oxide coating acts to protect it and unless this surface coating has been breached by the soaking I would doubt it would hurt the structure of the material.

Before I saw your last post I had wanted to tell you that I recently fount one of the single best carbon and cooked oil cleaners while cleaning the diesel carbon buildup out of a VW Tdi intake. Much better then Simple Green (at least for this use). It's called Super Clean and it comes in a purple bottle, I think it's made by Castrol. It is great stuff.

I hope that the pistons come out ok. Let us know what you find.

Jaysin

[entropy]

Originally Posted by TheBandit

It looks like the thinnest shims sold for these is 0.015in. I've read a typical acceptance range is around 0.025in from nominal. Something else I came across was recommending shimming the springs to 0.060in from coil bind (installed hieght = bind height + max lift + 0.060) - basically targeting the maximum seat pressures for a given spring while leaving 0.060 bind clearance. It seems to me like if the cam profile was designed around nominal spring pressures, I should shoot for those and just stick to the 1.800+/-0.025 range. Just sorta thinking out loud. What have you done in the past e?

The LS has an adjustable valve train (If memory serves) and I believe the setting is 1-revolution from zero lash, in which case I would shim as necessary to get the correct Intsl-Ht and I would not sweat an error in that number under 0.015 which is you say the minimum shim. The thing that would be worth checking is the valve train geometry BUT as you have not changed anything just cleaned stuff it should be the same as GM built in the first place. I would check the max lift available while in there just because........

Originally Posted by TheBandit

I read something about ....
10 mins..
hmm...
my pistons have been soaking
I wonder if I've done any serious damange.
They don't look any different
but this would explain the chaulky oxidation

There are two places that You now get to inspect: The wrist Pin Bores and the ring grooves, you need to measure them.
In addition I would seriously look over the entire piston for ANY pitting.
I do hope that you just relearned to read the side of the bottle of the chemical you intend to (mis)use.
A better choice would he Stoddard solvent (paint thinner) and a stiff Natural Bristle brush and getting 100% of the carbon off the top of the piston is largely a waste of time, just clean the OD and the ring grooves. Blow dry immediately (or rinse in Tri-Clor) and bag em.

E

[TheBandit]

Originally Posted by entropy

The LS has an adjustable valve train (If memory serves) and I believe the setting is 1-revolution from zero lash, in which case I would shim as necessary to get the correct Intsl-Ht and I would not sweat an error in that number under 0.015 which is you say the minimum shim. The thing that would be worth checking is the valve train geometry BUT as you have not changed anything just cleaned stuff it should be the same as GM built in the first place. I would check the max lift available while in there just because........

The LS uses a non adjustable valvetrain. Lifters preload can be altered with different length pushrods. I will be checking the lifter preload with an adjustable pushrod when the time comes. For installed spring height I am mostly concerned with pressures and bind clearance.

Originally Posted by entropy

There are two places that You now get to inspect: The wrist Pin Bores and the ring grooves, you need to measure them.
In addition I would seriously look over the entire piston for ANY pitting.
I do hope that you just relearned to read the side of the bottle of the chemical you intend to (mis)use.
A better choice would he Stoddard solvent (paint thinner) and a stiff Natural Bristle brush and getting 100% of the carbon off the top of the piston is largely a waste of time, just clean the OD and the ring grooves. Blow dry immediately (or rinse in Tri-Clor) and bag em.

Thanks for the advice. I'll inspect them for pitting and see if the bores / grooves show damage.

Jaysin - I checked Super Clean and it also says to avoid prolonged contact with aluminum.