so I got a basket case 400ci project someone started(I know I'm inheriting their problems etc but the price was right) for my '86 Camaro so I'm trying to ID some of the stuff I got and thought you guys could help I already positively IDed the 2 blocks as 400s. I have a set of pistons (with mixed rings some have them all some have none ughh) marked L2489 .030 on the face and TRW stamped under the skirt They are flat top just with machined out areas for valves I'm not too worried about this and haven't started looking yet they seem to just be 30 over pistons for that block but if anyone knows off the top of their head it would be useful before i start looking =) EDIT:>> Identified as TRW forged pistons for making a 406 with 5.7 inch 350 connecting rods I have good i believe stock 350 connecting connecting rods and I think original 400 connecting rods (not too concerned with that yet) The stumper for me that I'm working on is the crank I have it was sent out to get balanced and cleaned and was returned in a box with no paper work and thats how I got it. It says GM on it and the casting number I got from it is 3482442 Ive been looking from google for awhile now and haven't found anything at a couple places like this http://www.nastyz28.com/sbcmenu.html#crank it seems to skip over that number. does anyone know where to look for this information??? is it maybe different because its a pontiac crank or something? any ideas?

The L2489-30 is a Speed Pro forged piston to make a 406 with 5.7" rods.
http://www.jegs.com/i/Sealed+Power/8...0002/-1/744660

Recheck the crank casting number. There's a 3932442 with a 3.48 stroke. The 400 crankshaft will have 3951529. There were no other 400 cranks cast. Measure the mains. 400 cranks are larger.

Sounds like you need a 400 crank. The factory ones are cast so now is a good time to buy a forged crank.

http://www.mortec.com/cranks.htm

look here i did but did find anything

I couldn't find ANYTHING about that casting number, its stumping me i cant find it in any lists online or in my chevy books...Its in a box from 'speedway motors' all of this stuff belonged to guy building a race car it was everything to assemble a spare engine is it possible it could be like a non production crank, maybe goodwrench or something thats a newer casting for the 400 block? its basicly a whole rotating assembly and block i have im just trying to id it so i know what im working with =/ thanks guys

Also its important to note whatever the crank is its been machined (i assume to re balance and of course make it work with 350 5.7" rods because thats what those pistons are supposed to use) i haven't started measuring it yet but i have sent out an email to the company whose name is on the box the crank is in, no word back yet

Since it's been machined, it may have been re-ground to a different stroke. It probably did start with a 3.48 stroke, but the only way to know what it is now is to measure the journals, and stroke. Doesn't sound right for your application.

Turns out its actually a crank for a 350 (which I will use later with a 327 block I have because I don't want to give up the stroke) I'm assuming the guy was using this so he could stay in a certain bracket for drag racing or something???

Anyway...I need a 400 crank for 5.7 350 rods...
so my plan is try to find a donor motor, if not buy a new crank and go from there...

I was wondering does anyone know if the summit cams are any good? they seem very reasonably priced at $90
http://store.summitracing.com/partde...&view=1&N=700+

Also I was wondering about if there are any special head considerations on something this block? I have a spare set of 350 heads somewhere I was thinking Id put on to start Id think being sbc it would be just a direct bolt on...but any special considerations for heads on the 400?

Use a 400 head gasket as a template and drill the steam holes into the head.

One more thing to keep in mind.. When you install this motor you will have to check the clearence on the oil pan if you are still running the factory style y pipe.... (ask me how i know ) I just completed this swap at the beginning of the year and i used the 350 crank ( i like free reving motors and i always wanted a 377) you can pm me with any you may come up with.

BTW the oil pan you need is from a second gen z28 to clear the y pipe

400 block+350 crank =377?
a lot of guys use those to rev to the moon. that may be the way your motor is setup, in which the crank would work with everything you have.
few local guys have them on solid roller setups and they are real screamers.