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Well I guess this is getting rebuilt. I was just gonna do a cam and new gaskets but these bearings look bad, and it had low oil pressure at idle.

Hopefully the cylinders are round and won't need to be bored over. LT1, 90k.

-- Joe

https://cimg5.ibsrv.net/gimg/www.thi...aa9218a1f5.jpg
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Check for taper and ridge. If there really isn't any (doubt there would be), leave the cylinders alone. Don't hone them. DO line hone the mains to a standard bearing set, polish the crank, and size the rods. And of course get the cam line fixed up and new bearings installed there.

GD

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I don't have the equipment to line hone the mains. If it has to go to a machine shop, I'd probably just buy a new block. The last block I had machined cost me like $1,200.. I could have bought a splayed cap sportsman block for about that.
The bottom of the cyls have hone cross hatch. I'll try to take the heads off and get the rotating assembly out of it tomorrow for inspection.

-- Joe

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Where can you buy a sportsman block for 1200.00 ?????????

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https://cimg1.ibsrv.net/gimg/www.thi...7b91aef92c.png

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What deck height ? not even sonic tested. Plate honed with bolts or studs ETC. what did they use it all makes a difference in the end.

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I'm wondering why you wouldn't simply replace what is arguably the second worst fuel injection engine (pistons/optispark) in history with a cheap LS variant.
I'd even take a roller cam TPI engine over an LT1 any day. Optispark? Is there some reason you are keeping the original engine? Just want an original block?

I get a couple 5.3L for free recently, and they support 500-600horsepower. So it is hard for me to imagine rebuilding (anything) when free 500hp engines are available.

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I've been doing a lot with LT1's the last few years. Nothing wrong with Optispark. I know everyone gets their panties in a bunch when they fail, but I've changed many SBC distributors too.

LT1's already have decent heads and intakes. A cam swap, small blower, etc and they are very reliable and can make lots of power.

But besides that, you can convert the opti to a basic cam sensor, and add a crank trigger to the timing cover and run a megasquirt to control them too.

The reverse flow cooling takes a LOT of heat out of the chamber, which lets you run more compression on crap fuel, which means more power.

LSx engines have their flaws too. Just ask anyone who had a knock sensor fail, what a nightmare it is to change those.

I had a 5.3 in the shop for the longest time too. I was gonna stick it in something, but didn't wanna spend the money on a special oil pan, headers, intake manifold, etc just to play with it. Not so free anymore.

-- Joe

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I'm sure it's fine.

Chevy bowtie blocks are under $1100, dart SHP blocks are like $1500. They are all cheap. The local machine shops charge too much.

-- Joe

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I buy quite a few Bowtie blocks there not under 1100.00 dollars I can tel you that. I sell the Dart SHP block all machined for 1875.00

This is what done to the blocks
Machine work that is done to all Dart and Bowtie blocks, machined as follows –– Main housing bores chamfered
– Freeze plug holes and rear cam hole are chamfered
– Line honed to at least the middle of the spec or high side if needed
– Decked to your dimension
– Bore to your spec
– Plate honed using the same gasket and hardware that will be used in the end build
– Lifter bores checked and honed to the lifters that will be used in the end build
– Top of lifter bores chamfered
– Bottom of the cylinders chamfered
– Tap oil galley holes deeper
– Stroker clearance pan rail only
– Chamfer Distributor hole for O rings
– Cleaned ready to go

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I thought the pistons were good for 400hp and that was pretty much a max for those oem units

hah you couldn't give me a megasquirt to run a V8 on these days. OEM ecu from 02+ has a LOT more options (more complex which can be a bad thing) but they are cheap $30

I mean, you could just run the engine 10-15* cooler.... nobody is having LS cooling issues with moderate power (500-1000) that I've seen...

This I don't understand. I just put knock sensors in my 5.3 to get it ready to go into the car (last year I guess) and it was pretty simple. The intake practically jumps off the motor and I keep reusing the gaskets from 02' just fine with 15psi of boost so thats no problem. I've had a brand new set of intake gaskets sitting by but never needed them. Then there is that cover 'plate' which is a couple bolts to get off... no big deal again, then reach in and knock sensors are right there?

So THIS is the real reason why it might be a 'bad' idea. Or rather why the LT1 might be 'better'. Yeah its alot of nonsense to get the LS swap done I guess. But I figure this way... once its done... its done, you never have to buy those parts again. None of that stuff ever wears out (pan headers intake generally dont 'wear out') and in the event you change your mind they are all highly sought after, viable used parts you could sell easily IMO.

Just playing Devil's advocate! I know you whatever you do will be great :D

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Your name is vaguely familiar. Are you Carl ?

-- Joe

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Yes Sir

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No, they are hyper pistons. You can make 500+ hp, but yes, if you detonate they will break like any other hyper piston.

Currently ms2_extra and MS3 have more options in regards to supported ignitions, fueling strategies, I/O modes, boost control, launch control, etc. Being open source it's easy to modify and add or change behavior. The OEM stuff has more options in regards to emissions control, diagnostics, and interface to body control/stability control modules.

That's not the same thing. You can run higher compression + spark advance on a reverse flow engine because it pulls more heat out of the chamber. LS engines have taller intake ports and can make more power. There is pros and cons to both. LT1 engines "just fit", LS engines need special oil pans and intakes to fit most hot rod/fbody/etc applications.

Yup, it's a PITA buried under the intake. When they seize up in there it's all kinds of fun!

They changed the design on the later motors, like my 2012 6.0 have them on the side of the block.

For something like a cheap C4 or Thirdgen street car, an LT1 is a fantastic platform. For you guys like like the stock ECM's, the $EE mask is flash tunable and has enough options. These engines are dirt cheap and they fit without issue, all your SBC stuff bolts to them.

You can make way more power with an LSx but you'll have a higher investment, so that might not be the best bet for a cheap car. If my big power 412" blown SBC in my Formula every fails, I'll probably replace it with a build LT1 with AFR heads.

-- Joe

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Your the CNC blocks guy.

You are cheaper than machine shops around here. I'm not driving 3 hours to Gorham ME or whatever you are to save money though lol.

Let's say I shipped this LT1 out to be hot tanked, sonic tested, bored, line honed, and the little "fixes" it would cost me like $1200.. These machine shops get like $110 an hour.

I asked them last year to cut a crank for me. They wanted like $300 to grind a freaking SBC crank .020 under... I can buy a crank with bearings for half that on ebay.

-- Joe

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695.00

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That's a smokin deal. I paid my local guy about $1200 for all that block work. It's good work, but his prices are high. I think it's due to his "historic" downtown location. Taxes and utilities in the next county over are out of control.

Carl - can you do a 1956 Buick Nailhead (322) if the need should arise?

GD

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Does your shop use a CNC Machine to blue print blocks ??

I don't have the programs for that block.

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No I think for the most part they use old school manual machining equipment. Quality stuff - Sunnen, etc. And they definitely know how to use their machines. But not CNC, no.

GD

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Program?

You can't manually machine blocks ??

-- Joe

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The plate that goes between the block and machine is 1200.00

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Of course you can. But that's not what Carl does. He uses a CNC machine made especially for engines. Such as:

http://www.centroidcnc.com/cnc_engin...k_machine.html

I don't know if he has manual machines or not. Maybe he does and does not wish to do that type of work. Some shops have this technology, and some shops don't. You can do the job either way, but there are some things that aren't feasible without a CNC machine (too labor intensive to do manually), and the trade off is that you don't have the ability to use the machine for any old random engine without the proper hardware and software (programs) designed specifically for that type of engine.

GD

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I've never seen a CNC block machine. All the shops I grew up in had manual equipment.

I had to order a digital bore gauge, mine is missing. When it comes in I'll measure the cylinder and decide if it needs to be bored or not. I'm hoping I can just hone it.

It's one of those deals where if I have to bore it and get new pistons, might as well get new rods and crank too. Next thing I know I have thousands invested in a C4...

-- Joe


https://cimg5.ibsrv.net/gimg/www.thi...b518728c3e.jpg
https://cimg6.ibsrv.net/gimg/www.thi...4fd671c76c.jpg
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I Love pictures! Thanks for taking the time to share, I know time isn't free

I don't get to do any machine work or have blocks checked. But I do notice the same side-loading marks in 4-cylinders from the pistons I guess "wiggling around" at the dwell I think.
I'm curious if in your experience those marks are usually cosmetic, or if their indication of something that could be, or needs to be addressed, or just in general what you think about that.

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I think that the bearings showed strange wear, and the cylinder wear is not uneven yet the motor wasn't making any noise.I think that there was a lubrication issue, and I think some overheating at one point.

The rod caps look a little strange too. Again, it wasn't making any noise but the way the bearings fit in and there was some discoloration on the big end.

I'm assuming it's out of round, and will need to be bored over. Probably will go .030 over.

Maybe just do new rods. Crank looks good, though I should probably make sure it's perfectly round.

Machine shop wants $400 to hot tank, bore and hone the block. This is assuming the main line is straight and it doesn't need any additional machining.

I still want to check it though, if for some reason the cylinders ARE in spec I'll just put it back together with new rings and gaskets.

-- Joe

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Check with torque plate or head installed and measure up from the bottom. If the block is going to be bored make sure they don't bore off unsquared decks and plate hone with same hardware and gasket being used in the end build with a good hone or its a waste of time..

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I like LT1's.

I don't want to take a chance, I'm hoping that the cylinders can be honed but I think they need to be bored. This some weird marks and stuff in the bore. It ran great, other than the oil pressure being low when hot at idle but..

Anyhow, I'll probably use some H597DCP-30 pistons and some scat bushed I beam rods. As long as the crank polishes up OK, I guess it's not a huge deal to bore it it over.

What were you using for cam on the LT1 ? I was looking at the LT4 hot cam or the CC-305, either with 1.6 rockers (have them). This is a 6 spd car though with 3.45 gears so I don't want something too radical.

Heads + intake will be stock.

-- Joe

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I would just run those bore's as is. I mean you can measure and all that but without a bore plate to torque the bores... given I can see cross-hatching in the cylinders I doubt you will get any useful information from it. It may show some variations but you will have no idea if those variations would still be there once the torque plate (or head) was installed.

As I have said - unless you are going to BORE it with a torque plate. Don't even bother to hone it. Cast iron (normal) rings will seat just fine on their own. No honing required. I haven't honed an engine for ring replacement (excepting as the last step to a proper bore and plateau hone with a torque plate) for 20 years. Glad I stopped believing in that wives tale.... the engine will make better, more consistent compression and less wear materials and honing stone materials will get into the engine oil and foul it leading to bearing wear.

That's all assuming there's not too much taper or out of round. But honing it with a dingle ball isn't going to fix any of that....

My rule is - bore it or don't touch it.

GD

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A lot of that depends on what the ring manufacturer says. I usually do what the engineer that designed the rings says to do. As an engineer myself, I lose my mind when someone fails to follow directions for my own products. I hate to do it to another engineer.

There is no cross hatch in the wear area of the bore. It's below where the ring stopped.

-- Joe

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looks like that engine sucked a lot of dust-pretty heavy top of bore wear for only 90k-looks like one of those oiled cotton gauze type air filters was in use...LT1 engines are cool:distinctive sound,gear drive water pump,and distributor mounted like on an early Ford flathead :)

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The problem really is that the wives tale of honing for ring seating is so heavily ingrained and the fact that the guy on the other end of the phone can't see the bore tends to make them suggest a "light hone". Not because it's unnecessary, but because if they don't and the engine burns oil (for whatever reason - even if it's not related to rings), they will get blamed for it. Also a "light hone" isn't going to do anything useful, but also is unlikely to hurt anything in the short term - making inevitable damage due to accelerated wear basically impossible to blame on their recommendation to hone or not.

Chevrolet Power was recommending against honing back in the 80's "unless absolutely necessary".

In your second picture, looking at the cylinder off to the right you can see honing marks well into the ring wear area.

Measure it with a bore plate. That's the only way you will know..... if it needs to be bored over. Like I said if it's bad enough that it "needs honing" then it's not good enough to run without boring.

GD

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Here's some reading on the subject that talks about this mysterious "glaze":

http://www.snowvalley.20m.com/bikes/dnthone.htm

GD

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Yeah I've seen all the literature for and against. Half of that is perpetuated "common sense" that was made obsolete by improved ring manufacturing nearly 40 years ago. It does still apply to some very old designs, and to chrome rings, etc. It is not a one-size-fits-all situation though, and modern fuel injected engines don't typically wear out the bores like carbs did. My Vortec cylinders looked excellent at 177k miles. Better than that LT1 pictured even.

Also the ring manufacturers publish the honing criterion for machinists that are final honing to size after a rebore. So they need to publish the proper grit and required surface finish. That Wiseco article is perpetuating bull$hit. They aren't even a ring manufacturer. They make pistons. Which gives them some cred but not entirely enough IMO. Also it's mostly in reference to bikes which I have no experience with but the previous article I posted specifically was talking about then with exact opposite recommendation...... funny. The Hastings one lists a single grit - which I highly doubt would be suitable for all rings, of all thicknesses, in all applications - cast iron, chrome, and plasma-moly. There are a lot of variables..... also 220 seems impossibly rough honestly. That will tear the hell out of the rings. I bet they will seat alright - right before they overheat and lose their tension. I guess the old school THICK rings would probably survive. My guess would be with a loss of compression and a reduced lifespan.

My experience - especially with modern thin ring packs used on aftermarket pistons - is that honing (dingle ball, rough finish style) will produce too rough of a finish, does not control cross hatch angle, and does not address taper, out of round, ring ridges, etc.... leading to ring overheating and subsequent loss of ring tension. This leads to massive oil consumption and is then blamed on the rings "not seating". Which is exactly the opposite of what happened. They seated too much.

If you hone a cylinder with too much taper from ring wear the rings will flutter from the rapid expansion and contraction required by the tapered bore. So that's a waste of time.

The reality is that normal cast iron rings are EXTREMELY soft and will easily seat on a bore that is suitable for running. If there's not enough taper or out of round to require a bore job, then normal cast iron rings will seat almost immediately.

https://cimg8.ibsrv.net/gimg/www.thi...a607e5fc53.jpg

Thats from Chevrolet Power back in the 80's. As you can see they reccomend a rigid hone in an automatic machine, and a surface finish of 500 grit. VERY fine. And not to do it at all if you can help it. Also important to note the quote here: "Present day piston rings are lapped during their manufacture and no longer require a rough bore finish for good seating".

I really believe that the manufacturers are just telling people what they want to hear because they know no back-yard re-builder is going to believe them if they tell them the truth. I used to work on industrial equipment and for a period of time after changing to sealed bearings Baldor electric motors pulled the Zerk fittings out of all their standard duty motors. This led to such a high call volume at their tech support center they put the damn fittings back, with the instructions that they only put in 1-2 pumps of grease annually. The grease went into an antechamber next to the bearing - which was sealed and could not accept grease anyway. They did this SOLELY to stop the tech support calls. So no one is going to convince me that manufacturers always have the "right" answers to these questions. They have the answers that produce the best customer satisfaction - be they right or wrong.

Honestly - if it worked I would do it. It's not as if it's difficult or expensive (dingle balls hones are cheap in the scheme of things) - even to have the machine shop power hone them..... But I have had to fix too many botched "rebuilds" by other shops and give customers the "bad news" about their oil consumption on their recent rebuild too many times. Several of my direct competitors like to dingle-ball their rebuilds and they burn oil like no other. I actually had one of these shops tell a customer who called to inquire if his recent rebuild was "honed or not" (he was very unhappy with his 1 quart every 500 mile rebuild) that they could do an oil change for him and that they have special oil that it "won't burn". WTF does that even mean?

GD

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What's interesting, is the GM literature for servicing the newer stuff (mostly non v8 but still) says to not hone, but they are running different types of rings.

Anyhow. I'm gonna bore it .030 or .040 over. Right now I'm just trying to decide if I want to run it around 10.8:1 naturally aspirated, or 9.5:1 and toss a small self contained blower on it.

It is NOT a track car. It's a street car with air conditioning that I like to drive to work, the beach, etc. So I don't want surging cams, overheating, or any of that ****.

But I'm on the fence about running a hotter cam and trying to make 400+ chp, or running a nearly stock cam and like 6psi.

-- Joe

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True, and doesn't have the packaging issues that a C4 has (air inlet over the exhaust).

Trying to find dyno charts of combos with stock LT1 heads are difficult. It seems a lot of people do the LT4 hot cam, or they do head + cam package.

A friend recommended the CC-305, but has no dyno data.

-- Joe

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Both. You want some cam duration to reduce the low/midrange peak VE spike that the stock cam generates to avoid pinging at high load and low rpm.

It won't run shitty with 212 or 220's @ .050 from a mild roller, you'd barely notice.

And boost is always better :D

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Ok. So here is what we are doing folks.

Block is being bored to 4.031"
Deck will be 9.000"

I'm running a steel 3.48" stroke crank, 5.7" rods, and a 1.550" piston so that will put it .010" in the hole.

I'm running 10128374 heads, which supposedly are 54cc (need to CC them)

So with a .039" 4.166" bore gasket and my compression should be 11:1

-- Joe

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Not sure what advantage the final bore to 4.031 is gonna do for you? You still need to hone it after boring. Is your piston oversized? Special rings?

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Because that is what the piston manufacturer wants the finished bore to be.

-- Joe

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Going back and forth in my head about the cam.

The CC305 cam, assuming my chambers end up being what I think they are, will be 11:1 compression and 8.6 DCR.

If I run the CC503 cam, 11.1 compression would be 8.75 DCR. That would probably be tough with pump gas.

Buuut. If I polish my chambers to 56cc, my static compression drops to 10.8 and DCR 8.5 with the CC503 cam. The 503 in theory will make more power than the 305. Both appear to have a crappy idle lol.

Also changes my spring requirements. The CC305 can get away with 105lbs on the seat (although i'd set them up at 1.775 like stock, so it would be like 112lbs). The CC503 appears to want like 125lbs on seat.

I'm running 1.6 rockers with either combo, so max lift is .545".

Heads are being ported to a 1.050" CS.

-- Joe

-- Joe

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