Hey Guys,

Im looking around for a 350 motor for my camaro and came across a 1986 350 out of a suburban for 250 dollars complete. My question is, is that a good motor to start my build? Not having any of the casting numbers yet, does it sound like a motor i should go for?

Thanks

 

How much do you plan to use, and what are you going to replace?
If you're just getting it for the block itself, then you're fine, can't really go wrong, as long as it's not cracked, and preferably has never been overheated.

If you are planning on keeping the crank, rods, heads, etc... Then that's where the question gets interesting.
Find out what heads are on it, I really have no guesses, I think it's before the famed TBI swirl heads came out, so that leaves me guessing 993 or something. Either way not a high performance head.

The block, crank, and rods will probably be all you want to reuse. New heads, pistons (overbore), cam and intake manifold will be needed if you're going for some power.

 

^^^^


Even if you can only salvage the block its not too bad of a deal. If you can still use the crank/rods and slugs its definately not a bad deal.

But in any case the thing should be sent out and cleaned up at least (if not bored, decked and align honed ect..) and have it magnafluxed. Nothing would suck more than throwing that motor together only to make it half a block and find out you have a split block!

 

{edit: correction to the block RMS type. An '86 should be a 1 pc RMS)

You should probably look for a newer engine. The reason is that the '86 engine will be a non-roller. The heads won't be all that good and will have the original style bolt angle (for the intake).

Check the sticky's on top of the TBI board. There is one about an inexpensive upgrade by Fast355. Has good info on which engine to get.

RBob.

 

thx for the replies, i still don't know much about the engine. I will want to use as much as I can because im on a really strict budget except for cam, pistons, and maybe heads. I will be doing most of the work at my school shop so I will get discounts on machining and parts. I have many tools to my disposal.

From what I know, it is the 4 bbl carb model, so i'm pretty sure it doesnt have the dreaded swirl ports. I am looking to make around 275 hp at the wheels, so if the heads do turn out to be low compression heads, will a little porting and polishing help out with the flow and a thinner gasket maybe?

Any Ideas Appreciated!


Thanks

 

Ok, similar build to mine (and everyone elses...). low budget, keep it cheap, reasonable power output, etc.

I'd really try to find a roller motor, if you can. Post 1988 suburban, truck, caprice, etc. Just make sure it's setup for a roller motor. You get more power and reliability when you put in a nicer cam that way.

Heads - Find out what casting # they are. If the engine isn't too bad, you might be able to hone and re-ring it, and keep the pistons. I kinda doubt it though. Do the math on your compression ratio, some 416/081 heads can be ported up real nice, and work great on a 350, 'specially if it sports dished pistons still. They're virtually free, and you get the fun of porting them!

New heads are going to run you $1000 at the very minimum, so that's why i'd recommend that cash going into a good cam, and other parts, and just porting decent stock castings.

 

K So I haven't had any response from the seller about casting numbers but i did come across something else. There is a 1998 vortec shortblock for sale. I was wondering, if I could get some 081 heads on there from a 305 tpi motor would that be a good combo? The shortblock has a spun bearing but everything else is there.

 

yea, that would work great.
But if it's got a spun bearing, you know that doesn't just mean "needs a set of bearings" right? Chances are most of the bottom end is toast. I'm not sure if the heat can warp the block, but a line hone might be needed... Crank is definately toast.

 

alrite sounds good, one more question. What are some ways that i could bring down the compression so its not too high cus I still want to run on pump gas. I used one of the engine compression calculators and came up with around 11:1 compression, if i run a .05 inch head gasket, flatop pistons (Im not sure what kind of pistons the 5.7 vortec has) and the 58cc combustion chamber of the heads.

 

K well i found out that the motor has a spun rod bearing, so will that need a totally new crank? How much would one go for? Everything else is in good shape.

I am getting mixed opinions about this motor. My teacher is telling me that these motors aren't that strong. He told me that these motors have a flaw somewhere(don't remember the exact part but it has something with castle in it) aren't that strong compared to the older blocks. Now I respect his opinion because he knows his stuff, so I am asking everyone here for your opinion.


Thanks Once Again!

 

It probably wont need a new crank, most likely just cleaned up then oversized bearings.

But machining costs may vary and its more than likely it would be cheaper to find another crank!

 

Being a roller block, do those take different cranks than the non-roller blocks or are they just all the same?

 

the roller block will take a 1piece RMS crank, they're sometimes a few buck more. Summit or ohio crankshaft has new ones for ~$200. But yea, you might be able to just get it machined ($100).

No idea where he got the idea new blocks aren't as well made as old ones. New metallurgy (casting) techniques only improve things

Castle? China walls? Main webs? I can't think of anything that has the word "castle" in it...

You're not doing the math right if you're getting 11:1 CR. But either way, you will be on the high side, opening up the chambers on the heads (die grinder), will drop down the cr a bit. I opened up my "58cc" heads to 64cc's.
After decking my block a bit, i'm at 10:1 CR on the dot.

 

The only "flawed" blocks i have heard about were the blocks MFG'd in mexico...

But i though they only MFG'd the crate engines down there...

 

thx for the replies!!

I think i'm all set thanks to you guys. If I have nemore questions ill post them. Thx once again, i appreciate it. TIME TO BUILD ME A MOTOR !


Chris