Have I ruined my vortecs

[Rstyshackleford]

Hey fellas new to site couldn’t quite figure out the search. Been searching for porting tips on vortecs thought I I’d found what I needed and started with the intake and exhaust. With further research now I’m starting to 2nd guess myself.
Just wondering if someone could tell me if I’m on right track or need to start lookin for new heads
Btw std valve sizing going on a 350 with comp cams xr269hr-12 with a first intake and chip

Thanks in advance for any help for a beginner

[JoePorting]

Just go with a slightly larger intake valve and the larger intake valve valve job will clean that up. I wouldn't worry about the exhaust side. But when you port heads, don't cut into the valve job angles. Just cut to the lowest valve job angle.

[mag2555]

Just get a 3 angle valve job done, as the factory valve job is undersized by near .045" ( the valve is 1.94" and the stock seat OD is 1.890"). and you will be ok once the seats are freshend up.
The valve job will sink the valves by about .022" even if new valves are used, so you will need to mill the heads some to retain the same level of compression.

After these things get done and you go back to porting be sure to cut some narrow long strips of duct tape to set in place and protect the valve job area when your working.

You sound like your a true novist at porting so don't not revmove any more then .015" or material anywhere , just blend in Changes in form / shape lightly!

These heads flow great for what they are up 450" lift and as such it's really easy for a novist porter to screw them up and drop air flow numbers.

[Rstyshackleford]

Thanks fellas for the info. I’ll lug them to a machine shop. I measured at the taper of my untouched head and it measures 1.644 to 1.647. My handy work is at roughly 1.700. Should of put that in original post. I called them and he has a couple untouched vortecs there wondering if I should buy one instead of throwing good money after bad?

[mag2555]

If you can to get your rework flow tested to see if how you did then that might not be a bad idea if you can pick up other used ones cheaper then the costs of the valve job and a flow testbor 2 on your current heads.

[1980RS]

Hey fellas new to site couldn’t quite figure out the search. Been searching for porting tips on vortecs thought I I’d found what I needed and started with the intake and exhaust. With further research now I’m starting to 2nd guess myself.
Just wondering if someone could tell me if I’m on right track or need to start lookin for new heads
Btw std valve sizing going on a 350 with comp cams xr269hr-12 with a first intake and chip

Thanks in advance for any help for a beginner

Looks like that would clean up with a stone on the 60°

[Rstyshackleford]

Yeah I called around no one up here has flow bench. The fella who tapped rocker stud holes can do the valve job no problem. I guess my only question now is from your guys experience with these heads do anyone think I have hurt flow with the mods down by the seat, bowl area? I was planning on leaving intakes rough and polishing out the exhausts.

[mag2555]

Can't really tell from your photo's, but blending out the 60 degree bottom cut will always hurt airflow numbers up to around .300" lift since your reducing the Venturi effect at those lifts.

[cardo0]

D. Vizard details porting vortec heads w/pics in his book "how to build performance sbc on a budet". Book is less than 20 bucks.

[RevTheory]

D. Vizard details porting vortec heads w/pics in his book "how to build performance sbc on a budet". Book is less than 20 bucks.

[Rstyshackleford]

Thanks for all the help everyone . I’ll be looking for that book for sure!!

[gmrocket]

Hard to see the exhaust seat .

Intake seat isn’t hit, and it’s really wide so you have lots of metal left to fix it up

[gmrocket]

xxx

[Rstyshackleford]

I’m not much of a photographer but I was careful not to hit any seats just a little aggressive on the last angle not sure what it’s called the throat or backcut? I assumed the velocity on these heads were created by the ramp and pinch point at the start of bowl

[mag2555]

There's two different velocity high points in any head because there are two distinct flow patterns in every head.
At some point in every head the flow pattern changes from the air at low lifts ( up to about .300" at times) going around the valve and taking the path of least resistance thru the runner to get to the back of the valve, and then once above .300" lift the volume of air passing thru the running is forced to start following the shape of the basic runner and bowl to make its way out into the chamber.

So you have a low lift peak VALVE velocity point and then a higher lift peak PORT velocity point to deal with.

In the factory Vortec heads they finessed the design to get a nice level of low lift flow and high lift flow while getting a good flow balance between ports with this casting.

A novist porter without proper guidance will have a hard time improving on these under .350" lift flow numbers even if the head gets fitted with a 2.02" valve.