S/C vs. N/A differences (series 1)
 

I know there are a few internal differences. Since I am going all out on the rebuild of the S/C motor, and replacing many internal parts along the way, I am in need of this information. I can find many S1 N/A's around here, and 1 in particular since it only has 80k on the clock. So far, I only know that the pistons and connecting rods are different. The crankshaft is the same. In particular, I want to know if the camshaft is the same, but any other parts that are different please post. Maybe once a complete list is done, maybe post it in tech info.

As far I know other then the block n/a is bascilly compelte different

Not *completley* different, but the major components were upgraded internally due to the higher stress levels. It's obvious that the intake manifolds are different, and the accessory drive, but I am looking for the not-so-obvious. The FSM gives different directions for connecting rod-piston separation between the 2 engines, which tells me those are different in design. From my research, the crankshafts are identical (which doesn't make sense, other than GM overbuilt the crankshaft). The heads are the same between the 2 models too, though the springs and valves may or may not be (again, more research is needed for that). For now I am going to assume the cams are different, but I am hoping to have a definitive answer while at work today. EDIT: Autozone lists the same camshaft for both applications.

Here's the list as I know it:

Pistons (pistons and rods use a sleeved/bushing wrist pin, rather than floating like the L27)
Rods
drive axles (much beefier)
harmonic balancer (don't re-use your original 93 balancer. Get a new one)
fuel pump (new also. This and the HB are long past due)
LIM (duh)
accessory brackets
wiring harness
PCM

This is off the top of my head. I've probably overlooked one or two little things.

Moving to General Chat.

Ooops...I guess I should have stated "long block" differences :? Basically, the rotating mass (w/exception of the crank and cam) is the only difference between the L27 and L67. Remember, only discussing internals, no accessories.

My balancer looked good from what I could tell, but will replace it when this Frankenmotor is running. Same with the fuel pump...will prob go with a Walbro unit.

Thanks for the input guys...I will have pics of the teardown up soon, already have the radiator-side head off, should have more comming off tonight or tomorrow.

I posted the other 'non rotating' stuff simply because someone else in the distant future may dig this topic up for a different purpose than you are needing it for.

eventually im gona put and SC'd drivetrain in mine...after this one runs it's course...but that would just mean swaping them out...so....but i did have a question...would you/should you stiffen the body or something...or are there any other mods needed to go from N/A to SC'd?

Ya need any help? I also have an engine hoist if you want to pull the entire motor out

The frame and subframe are identical. But the L67 powered cars USUALLY have FE2 suspension.

I already have a full-fledged SSEi, but my problem, as clm2112 found, pickings are extremely slim on l67's here, and when one is located, it's either been pillaged beyond salvage, burned, or already taken. Same with those transmissions. Another option is to buy a remanned motor, but those aren't cheap. So, the only logical thing to do is rebuild what ya got. Since my son will be here this week, funds are now pretty limited, but I still want to get this car going. I won't give up on her...already gone pretty far with her as it is. Since the L67 and L27 share alot of the same parts, it only makes sense from a budget standpoint to seek out a low-mileage L27 to source parts from, or better yet, transfer L67-spec parts to it. I found one here at the u-pull-it w/ less than 90k on it that had been t-boned, and everything inside the motor looks near-new. Just transfer my L67 pistons and rods and it should be good to go!

I may very well need that hoist when I go get that motor. A local shop is doing me a huge favor by letting me do half the work for this buildup, and the other half of the work has been done via trade on some car audio equipment I am not using, so parts is all I need to come up with.