Iron Vortec head info on YouTube

[biker]

I ordered them from Summit, there are the 062’s. I pulled the rocker arm studs using washers & a nut. Bought one of those rocker stud alinement tools for screw in studs. Somehow I got a couple of studs not inline with the others, leaning towards the valve a dergree or two. So be aware if you use the same alinement tool. First Let Me Say I’m not a professional at porting!!! but I did a boatload of homework before I started. I didn’t have a air grinder at the time so I used my rotozip. A Dremel tool takes to long & won’t have the reach you’ll need. Ended up buying an air grinder and a couple of 1/4 x 6” rotary files & a few 1/4 x 2 1/2” files. I’ve seen those porting kits that are rolls of sand paper. There good for polishing not for a full port job. Rotary files cut or grind cast iron pretty fast so you have to be careful. You can’t be forceful, heavy handed etc. Just light touches moving side to side. The roof or top of the runners don’t need any work. The short side bend & the floor or bottom of the runners require most of the grinding & on Vortec’s you don’t need to remove very much. Don’t polish the runners, leave them a rough surface. You can polish the chambers. I did use the Dremel for this, used some thick rubber disc with grit infused in the rubber, worked great.
Enough of that, porting.
Engine is a 350 bored 40 over, sadly it’s a 2 bolt main with ARP bolts. I was using the original 1978 crankshaft but worried about it’s age and bought a new Eagle cast crank. Wasn’t planning on spinning a 2 bolt main block really fast. 6” SCAT rods which let me use lighter DSS forged pistons. Howard’s roller cam, 266/270 Dur@050 213/217 lift .485/495 110 LC I wanted a cam that started sooner in the rpm range. It comes on cam about 3300 rpm’s, hits pretty hard but it does fall off about 5800 rpm’s. That’s about 130 mph in 4th gear, good enough for me. Lunati roller lifters. 750 Eddy carb on a Eddy Performer intake for Vortec heads 2116. An a regular no frills HEI distributor. 700r4 transmission & 3.42‘s in the rear.

Thanks man! That's a huge help. If I touch the ports at all, I will go easy as you say. I have a good set of carbide burrs that I use for general fab stuff, but they will go thru cast like butter.
Sounds like you have a great combo. Absolutely nothing wrong with a 2 bolt. I'm using the complete stock vortec 350 bottom end on this one and it's a 2 bolt.

 

[VORTECPRO]

I ordered them from Summit, there are the 062’s. I pulled the rocker arm studs using washers & a nut. Bought one of those rocker stud alinement tools for screw in studs. Somehow I got a couple of studs not inline with the others, leaning towards the valve a dergree or two. So be aware if you use the same alinement tool. First Let Me Say I’m not a professional at porting!!! but I did a boatload of homework before I started. I didn’t have a air grinder at the time so I used my rotozip. A Dremel tool takes to long & won’t have the reach you’ll need. Ended up buying an air grinder and a couple of 1/4 x 6” rotary files & a few 1/4 x 2 1/2” files. I’ve seen those porting kits that are rolls of sand paper. There good for polishing not for a full port job. Rotary files cut or grind cast iron pretty fast so you have to be careful. You can’t be forceful, heavy handed etc. Just light touches moving side to side. The roof or top of the runners don’t need any work. The short side bend & the floor or bottom of the runners require most of the grinding & on Vortec’s you don’t need to remove very much. Don’t polish the runners, leave them a rough surface. You can polish the chambers. I did use the Dremel for this, used some thick rubber disc with grit infused in the rubber, worked great.
Enough of that, porting.
Engine is a 350 bored 40 over, sadly it’s a 2 bolt main with ARP bolts. I was using the original 1978 crankshaft but worried about it’s age and bought a new Eagle cast crank. Wasn’t planning on spinning a 2 bolt main block really fast. 6” SCAT rods which let me use lighter DSS forged pistons. Howard’s roller cam, 266/270 Dur@050 213/217 lift .485/495 110 LC I wanted a cam that started sooner in the rpm range. It comes on cam about 3300 rpm’s, hits pretty hard but it does fall off about 5800 rpm’s. That’s about 130 mph in 4th gear, good enough for me. Lunati roller lifters. 750 Eddy carb on a Eddy Performer intake for Vortec heads 2116. An a regular no frills HEI distributor. 700r4 transmission & 3.42‘s in the rear.

I run my 2 bolt 7000 RPM often, you should be fine if everything is well prepped. I've seen the piss cutter videos, until I see some track testing its not that interesting to me.

 

[biker]

I run my 2 bolt 7000 RPM often, you should be fine if everything is well prepped. I've seen the piss cutter videos, until I see some track testing its not that interesting to me.

Thanks man. The one I'm putting together now will not be spinning to 7000 rpm. Just looking to have a healthy roller cam small block for my old caprice cop car. 700R4, would like to stick withbthe stock converter.

 

[1980RS]

Some pics of my Vortec’s.
One thing I found is the chambers on mine where 62cc. I didn’t want to go to far on grinding out material. I cleaned up under the valve seats & streamlined the valve guides on the intakes. Cleaned up casting flash in the runners an ruff up the runner walls & took off some material on the short side turns.Cleaned up the exhaust valve guides & smoothed the chambers & port matched the heads to the intake. Polished the back side of all the valves. Comp Cam retainers for LS1 beehive springs & Comp Cam self aligning 1.5 roller tip rockers & new thick walled pushrods. Wished I could of had these flowed but didn’t. I did dimple the chamber walls a bit but decided not to go any farther.

On your intake port roof always becarful to not take out the ski junp at the top of the port when grinding. I have read it may ruin the port. Other then the bowl area I did on my 062's I did not touch the port opening at all, they still went 250 cfm on the flow bench.

 

[Jcanfixall]

Vortec Cylinder Heads: The Definitive Guide

Guys, Dave "Dirt" Reynolds has suggested that we devote some space on the message board to Vortec heads. Cylinder heads are arguably the most important link in the "power chain", so it is certainly worth its own dedicated area for discussion.

nastyz28.com

 

[2ndGenCrazy]

Just my humble (not so) opinion on these heads.
If you remove the swirl ramp, you no longer have a Vortec head.
The swirl is why they named it after a flow vortex.
You might as well port a 60's casting.
I worked at GM during the development of the tumble and swirl characteristics for stock head castings.
The port and chamber are designed to work in unison with one another.

 

[G72Zed]

Just my humble (not so) opinion on these heads.
If you remove the swirl ramp, you no longer have a Vortec head.
The swirl is why they named it after a flow vortex.
You might as well port a 60's casting.
I worked at GM during the development of the tumble and swirl characteristics for stock head castings.
The port and chamber are designed to work in unison with one another.

Thanks for sharing your opinion 2ndGenCrazy.

It's amazing what the proper "shape" can do for performance, both port and chamber vs the all so hyper focus raw "CFM - Flow" numbers.

Any other insight/data you could share ?? or allowed too ?

 

[2ndGenCrazy]

Thanks for sharing your opinion 2ndGenCrazy.

It's amazing what the proper "shape" can do for performance, both port and chamber vs the all so hyper focus raw "CFM - Flow" numbers.

Any other insight/data you could share ?? or allowed too ?

We could chat about mixture motion and a convoluted flame front if you like.

 

[G72Zed]

As Frasier Crane would say "I'm listening".......

Did GM ever produce or think about the chambers in 40-45cc design ??

 

[1980RS]

Just my humble (not so) opinion on these heads.
If you remove the swirl ramp, you no longer have a Vortec head.
The swirl is why they named it after a flow vortex.
You might as well port a 60's casting.
I worked at GM during the development of the tumble and swirl characteristics for stock head castings.
The port and chamber are designed to work in unison with one another.

There is no swirl ramp on the SBC Vortec head, only on the L-29 BBC head which I took out on the advice of a head porter who worked under Joe Mondello. Must not have ruined them too badly, my car ran [email protected] with limited testing that day. If there is a swirl ramp on the SBC 062/906 could you please show me. Thanks.