PDA

View Full Version : 96+ Vortec 350 teardown suprise



94Blackbird
03-20-2012, 11:35 PM
Ok, so here's what happened. I bought a junkyard vortec 350 to get the rotating assembly to do a budget boost friendly build. I finally got around to tearing down the shortblock, and when I pulled the oil pan, instead of the stock rotating assembly, I found GMK stamped rods with the balance pads on the bottom of the rod caps, with the piston order stamped on the bottom. Not hard to identify, that info is plentiful.

The Block and heads that were on the motor are from a 96+ vehicle, there is no mistaking the intake manifold and the timing cover with the cam sensor in it. Besides the fact that I checked the vehicle itself to ensure that it was indeed the correct generation vehicle. so it appears to have been rebuilt at one point.


And here is the crux of my post, and more of a question of curiosity rather than hoping for that one in a million find.

I can't definitively I.D. the camshaft that was in the motor. On the timing gear end is stamped 305 following the curved of the camshaft. On the bellhousing end, is stamped 1264, next line is 3 23, next line is 9049. Also, on the other side on the bellhousing end of the camshaft is a K and a 0 stamped into it.

I don't have access to a set of micrometers, and I don't want to pay to have that work done. I don't need the cam to be anything, I'm just curious if anyone has any info that may help me here since the rest of the internet has thus far proved quite useless in my quest for the answer.

Thanks in advance!

david068513
03-24-2012, 02:07 AM
try calling a cam company and giving them at info

94Blackbird
03-24-2012, 10:37 AM
try calling a cam company and giving them at info

Thanks for the thought, but I'm pretty sure it's stock. I found the cam that came from the Iron head LT1 I'm rebuilding, and it looks identical, so I'm going to leave it at that lol

joelster
03-24-2012, 11:43 AM
A little mic from Harbor Freight will set you back $10. It isn't the most accurate thing in the world but it will easily tell you the lobe lift.

94Blackbird
04-22-2012, 05:22 PM
Got it solved, pretty sure it's a stock cam. Friend of mine has dial calipers and the numbers came out very, very close to a stock cam

shadowbandit
04-22-2012, 07:29 PM
I know this may be a dumb question but a96-97 vortex 350 has a forged bottom end? And fits into a lt1?

94Blackbird
04-22-2012, 08:24 PM
I know this may be a dumb question but a96-97 vortex 350 has a forged bottom end? And fits into a lt1?


vortec 350's use PM rods and cast cranks, along with dished hypers. Someone rebuilt the motor I pulled from the junkyard, and either used older forged rods or they spent alot of money on GMPP pieces. I still haven't positively id'd the con rods, but I know they are not stock as I have a stock set of vortec rods laying around.

zraffz
04-22-2012, 08:25 PM
I know this may be a dumb question but a96-97 vortex 350 has a forged bottom end? And fits into a lt1?

No the vortec doesn't have a forged bottom end. They are interchangeable between LT1/Vortec 350 though. He uses the vortec rotating assembly to lower his compression and not have to pay to have it rebalanced.

94Blackbird
04-22-2012, 08:42 PM
No the vortec doesn't have a forged bottom end. They are interchangeable between LT1/Vortec 350 though. He uses the vortec rotating assembly to lower his compression and not have to pay to have it rebalanced.


Yup, exactly. Though I got lucky with the motor I pulled, it had recently been rebuilt and has rods that are not stock

shadowbandit
04-22-2012, 10:18 PM
How does a vortex bottom end have less compression I'm new to this hole boost thing

94Blackbird
04-22-2012, 10:21 PM
LTx pistons are flat top with about a 4.5 cc valve relief. Vortec pistons have a 13 cc dish.

Iron head LT1's are 10:1 compression, where as Vortec 350's are right around 9:1 or so
Iron LT1 heads and Vortec heads are essentially the same (the vortec heads are actually patterned after the Iron LT1 heads, including the 64cc combustion chamber). They got the lower compression for the standard flow cooled motors buy using dished pistons.

zraffz
04-23-2012, 05:25 PM
Isn't the LT1's stock chamber 58cc?

94Blackbird
04-24-2012, 07:36 AM
Isn't the LT1's stock chamber 58cc?

You are correct if we were talking about the Aluminum heads that came on firebirds, camaros and corvettes. The Iron heads that came on caprice's and Impala's are different and have 64cc chambers.

zraffz
04-25-2012, 04:41 PM
You are correct if we were talking about the Aluminum heads that came on firebirds, camaros and corvettes. The Iron heads that came on caprice's and Impala's are different and have 64cc chambers.

Never mind.. stupid question. Knew that and know why you are going that route.