Quaraxkad's '92 Cutlass L67 Swap finally begins!

[Turbocharged400sbc]

ive never seen an SII l36 rod shatter like the Powdered Metal SII L26

the cast rods will bend but they also arent as necked down at the piston as much as the PM L26 rods

l32 and l67 rods are probably not far from each other as far as strength but ive seen all too often how brittle PM parts can be

the PM rods are cheaper to make and machine....thats the only reason gm switched to em....thanks beancounters

[Galaxie500XL]

Wondering aloud here...I wonder if the piston failure was caused due to detonation/misfire from that coil with all the rust on the top? Was that the cylinder that was fed by that coil?

Theory: Engine was running like crap, but the previous owner ignored that, and flayed away at the thing.

[Quaraxkad]

Wondering aloud here...I wonder if the piston failure was caused due to detonation/misfire from that coil with all the rust on the top? Was that the cylinder that was fed by that coil?

Theory: Engine was running like crap, but the previous owner ignored that, and flayed away at the thing.

I was about to say yes... But then I remembered that the block was upside-down. Cylinder 2 had the bad coilpack, but cylinder 1 is the exploded piston. To double-check that I just went out and pulled the spark plugs. All but #3 and #5 are damaged, #1 is the worst, more pics tonight. So I'm thinking there might be more damage to the heads. My current plan for today is to pull the SC and heads when I get home. If they are salvageable I'm keeping them, returning the block for a refund (I'll have them charge me for the parts I keep) and will then start the search for another shortblock. There are a LOT of L36s at the yard, so I'll find one of those with low miles that looks good. Preferably from a rear-end collision vehicle...

[Turbocharged400sbc]

i <3 burn victims

i have a ~80-120k l32 on my garage floor from a roached 04 compG. 125$ for the whole thing (mainly cause ive put the junkyard guy's kids through college by now)

wear long sleeves and throw away the shirt after....the fiberglass from the burned glass reinforced plastics... itches like a mofo

[no1kicker]

I know a complete L26 or L32 is not a simple drop-in swap into a Cutlass, but are the bottom ends interchangeable with the L67? If it's just swapping parts, I can do it, but if it requires any kind of fabrication I can't get into that.

All the L67 stuff will bolt up to an L26 shortblock. You will have a bit higher compression due to the pistons. Lots of GTP guys have done this, probably due to the L26 being cheap and more available. Check on car-part.com for prices, there is one in my area from an 09 Buick with 38k for $350, and other similar deals. You need everything but the shortblock from an L67. SC, heads, LIM, tensioner, crank pulley, and probably a few other things. Search for "top swap" on here and other sites.

[Quaraxkad]

Good news, maybe! I pulled off the SC and the heads today. The heads look like they're alright at first glance There is a lot of debris, but I didn't feel any damage. I'll do a thorough cleaning tomorrow, and take a closer look at them and the SC.

The block is mostly disassembled. I think the only thing I forgot to pull off that I will need is the crank pulley.


Here's the bad cylinder


A pair of grooves worn into the cylinder wall

All the L67 stuff will bolt up to an L26 shortblock. You will have a bit higher compression due to the pistons. Lots of GTP guys have done this, probably due to the L26 being cheap and more available. Check on car-part.com for prices, there is one in my area from an 09 Buick with 38k for $350, and other similar deals. You need everything but the shortblock from an L67. SC, heads, LIM, tensioner, crank pulley, and probably a few other things. Search for "top swap" on here and other sites.

I was familiar with the topswap, but I was under the impression that was to swap a SII S/C onto a SII N/A block or a SIII S/C onto a SIII block. I didn't know the two shortblocks were interchangeable. I hadn't researched that route because I had always planned on starting with an L67.

All the engines at the yards around here using car-part.com are $600 minimum, usually closer to $800. I just checked L26 and L32, same thing.

[pshojo]

The whole time I thought the new rods were better. They would be little lighter ? For most daily driver apps should be fine. The supercharged piston SIII ate ceramic coated.

[Quaraxkad]

The whole time I thought the new rods were better. They would be little lighter ? For most daily driver apps should be fine. The supercharged piston SIII ate ceramic coated.

I thought they were better too. Forged parts are typically much stronger and lighter weight than cast.

[runt]

I thought they were better too. Forged parts are typically much stronger and lighter weight than cast.

Forged, yes. If they are in fact a powered metal pressed part they probably aren't. The technology in P/M has some a long way but it's not nearly as reliable as a cast or forged part.

[Quaraxkad]

Forged, yes. If they are in fact a powered metal pressed part they probably aren't. The technology in P/M has some a long way but it's not nearly as reliable as a cast or forged part.

Many references I have seen say they are Powder Forged. I'm not familiar with all of the machining terms, I figured forged is forged. Either way, I'll be looking for another SII block after I return this one, I know there are a lot of them available here.

[Turbocharged400sbc]

The whole time I thought the new rods were better. They would be little lighter ? For most daily driver apps should be fine. The supercharged piston SIII ate ceramic coated.

they are more consistent...its a near net weight "forging" so they no longer have to weight and machine each rod to get it close to the target weight (=/- 2-5 grams each on some motors) that saves time and labor and tooling for each rod...the bean counters love that shit...gearheads dont
for a stock 240/260hp motor its plenty strong...but we arent happy with "plenty"

the pistons are not ceramic coated...they are anodized like all sii pistons but with the addition of a graphite skirt coating to reduce friction against the cyl thrust wall which is quite high due to the high rod angularity....this and other changes such as 3.05 fdr allowed gm to get the na 3800 certified as a SULEV (super ultra low emissions vehicle)

I thought they were better too. Forged parts are typically much stronger and lighter weight than cast.

forged parts are stronger...these are only forged is the shitiest sense of the word since the powder mix is put into a mold then "pressed/forged into shape...then that part is heated to the point the powder forms bonds with the powder around it.
homogenization of the mixture is fairly good but like castings occlusions can still happen which weaken the parts.
since PM rods are pressed into shape they all have the same dimensions and have reduced machining but the real proof that they arent anything other than an acceptable strength dirt cheap part is that PM rods use fractured caps. the bigend/rod boltholes/threads are machined then the cap is cracked off the rod creating a 2 piece rod and cap MUCH faster than maching two (much more ductile) castings and machining them, then bolting together, then machining and honing the big end

not let me emphasize this.....they CRACKED the cap off the rod.....they didnt cut it, they BREAK it...they dont and cant do this with cast rods since they arent as brittle....fuck you beancounters

Forged, yes. If they are in fact a powered metal pressed part they probably aren't. The technology in P/M has some a long way but it's not nearly as reliable as a cast or forged part.

x2 rearend/differential gears are now made via PM tech and ive actually seen them shatter....but its much cheape rthan machining and hobbing a gear like in "the olden days" where the gears would be intact but friction welded to the crosspin or the cast iron carrier...but hey...it only has to last till its out of warranty

Many references I have seen say they are Powder Forged. I'm not familiar with all of the machining terms, I figured forged is forged. Either way, I'll be looking for another SII block after I return this one, I know there are a lot of them available here.

thats sorta what they want you to think and you can see its working...the term is "near net weight forged powdered metal" forged in this term is interchangable with "pressed/molded" as if they are a god damned cookie.
you wont find any PM tech inside any serious engine build....cause saving money and ensuring reliability/strength are at complete odds

[Quaraxkad]

they are more consistent...its a near net weight "forging" so they no longer have to weight and machine each rod to get it close to the target weight (=/- 2-5 grams each on some motors) that saves time and labor and tooling for each rod...the bean counters love that shit...gearheads dont
for a stock 240/260hp motor its plenty strong...but we arent happy with "plenty"

the pistons are not ceramic coated...they are anodized like all sii pistons but with the addition of a graphite skirt coating to reduce friction against the cyl thrust wall which is quite high due to the high rod angularity....this and other changes such as 3.05 fdr allowed gm to get the na 3800 certified as a SULEV (super ultra low emissions vehicle)
...
forged parts are stronger...these are only forged is the shitiest sense of the word since the powder mix is put into a mold then "pressed/forged into shape...then that part is heated to the point the powder forms bonds with the powder around it.
homogenization of the mixture is fairly good but like castings occlusions can still happen which weaken the parts.
since PM rods are pressed into shape they all have the same dimensions and have reduced machining but the real proof that they arent anything other than an acceptable strength dirt cheap part is that PM rods use fractured caps. the bigend/rod boltholes/threads are machined then the cap is cracked off the rod creating a 2 piece rod and cap MUCH faster than maching two (much more ductile) castings and machining them, then bolting together, then machining and honing the big end

not let me emphasize this.....they CRACKED the cap off the rod.....they didnt cut it, they BREAK it...they dont and cant do this with cast rods since they arent as brittle....fuck you beancounters
...
x2 rearend/differential gears are now made via PM tech and ive actually seen them shatter....but its much cheape rthan machining and hobbing a gear like in "the olden days" where the gears would be intact but friction welded to the crosspin or the cast iron carrier...but hey...it only has to last till its out of warranty
...
thats sorta what they want you to think and you can see its working...the term is "near net weight forged powdered metal" forged in this term is interchangable with "pressed/molded" as if they are a god damned cookie.
you wont find any PM tech inside any serious engine build....cause saving money and ensuring reliability/strength are at complete odds

Good info, thanks! What about the strength of the pistons? I found an article (http://www.enginebuildermag.com/Arti...ck_engine.aspx) that says there are 5 different pistons used throughout the whole 3800 range. It looks like there are only two used on all SII and SIII, and those are the N/A pistons and the S/C pistons. Are they only different in that they are for different compression ratios, or is the S/C version supposed to be stronger?

[Turbocharged400sbc]

SC piston is stronger in the upper ring land area since the rods are .1inch shorter than the NA rods it allows for the piston compression height to be .1" taller which means they are able to move the top ring down by .1" so there's more meat in the upper ring land so with the extra dish for lower compression the piston is still strong

dont knock and both should be more than durable enough for a sc motor

[wbodieseasytocomeby]

was the gauges a direct plug in from the analog ones

[94 olds vert]

was the gauges a direct plug in from the analog ones

No in order to put one of those in some wires need to be moved around in the harness.