I was just looking at my new 2003 TPIS catalog, and I noticed under their machine shop services section that they can drill Vortec heads for a standard manifold. Has anyone heard of this, is it possible? Doesn't the Vortec heads have raised ports?

**** that modifying the heads for the intake bull****. Do what EVERYONE else has been doing since the sonsabitches at gm decided in 87 that they could **** over aftermarket companies and grind out the middle four intake bolt holes on the manifold to make them fit...the manifold doesn't leak, it's attached strong, and it's a ****load cheaper...

Yes you can redrill trhe vortec heads with the pre 86 intake bolt pattern.

Yes the vortec ports are raised and shaped different.

So a normal sbc manifold will not fit right.

There are many vortec style manifolds available at reasonable prices, why f***k with the bolt pattern.

www.professional-products.com

There are 3 vortec manifolds available from trhis Co. alone.

How well it seals and how well the ports line up are gonna depend on the intake manifold you're using. I've seen some work ok with the re-drill and others that leave very little room for the gasket to seal at the top of the ports.
It's safer to just get a vortec intake, but it can work if the manifold has the material up top.
-Rich-

Rich is right. It depends on the intake manifold you want to use with the vortec heads. The limiting factor is the material up top on the intake flange.
Here's a picture of a standard SBC intake on a set of vortec heads (fastburn). I do not know what the intake maker was.

We used to redrill the vortec heads to fit Victor Jr 4 bbl intakes on my local dirt track, but now they have the vortec manifolds ( both 4 bbl and 2 bbl), so we don't have to do it anymore.
Why do it? After the cost of the machine work and the cost of the standard intake you can buy a vortec intake.
Whatever floats your boat, just my opinion. :rockon:

Bumping an old post up. Found this in search and needed to ask another question. I hope no one minds me doing this.

I have a Eldebrock Tpi base that someone modified to fit a Felpro 1206 intake gasket. It has material welded on to the ends. Would this be a good enough seal for the Vortec heads? I am considering buying a set from Jim Pace that has been drilled for earlier manifolds.

Vortec heads have raised ports. You need to use a raised port
vortec style intake to get the advantage of the vortec design.

SDPC sells a vortec TPI intake.

TPIS sells a Mini Ram EFI intake MiniramIII

GMPP sells a Ramjet EFI (vortec) intake.

The stock 96/2000 Vortec 5.7 L-31 truck EFI intake manifold has some potential too.

Use one of these for a vortec EFI project or get different heads.

F-BIRD'88,
No sense going with the intakes named above when I can probably use what I have with some performance. I was considering the Vortecs to save me some work. I am planning a mild 350 build up. While we're on the subject, I wanted to ask you a question. I've followed your posts on the 305 heads potential. I was wondering if a set of 601 castings have enough material to port them out to a Fel pro 1206 gasket size?

I bought a set awhile back from Performance Chevy in Az. They are 601 castings with 1.94/1/50 valves, three angle valve job and a stage one port (as they call it) Supposedly this is a bowl blend. They are cut for screw in guideplates and have .510 springs. I was going to attempt a port job following the posts you and Sitting Bull have made. I also have the book by the Vizard guy. It's a little complicated for a first timer but I am learning more as I do more research. I was hoping to port these out the best I can.

One concern I have is the heads only have 10k or less miles on them since I got them. I've seen people post how after they are done porting them, they send them off to the machine shop for the larger valves. Since I already have the larger valves, do I need to send them off for anything else? I guess I would have to be very careful around the valve seats when doing the porting.

Any help would be greatly appreciated. Thanks

As long as you don't hit a seat, you'll be fine.

You can port them to a 1206 gasket if you want. If your manifold is not that big just go to a 1205 gasket.
Making the port entrance that big will only favour a more radical motor
with lots of cam lift and a single plane intake.
But that still leaves you a lot of room to port for a street motor.
Can't tell you exactly what the potential of the 601's are. I've never ported or flowed them, But Sitting Bull seems very happy with his. They are a little different than the HO/TPI heads.
They don't look to have as nice a bowl contour to me.
A flowbench would tell the tale.

Can't see how butchering up a set of vortecs will help ya.
The conventional ports on a normal intake will not match a vortec
raised port. You could carve and epoxy the intake up to get a port match but you'll have tons of time in it.

Not really worth it. Just buy a good set of other heads.
Like a set of Dart SS (165cc) or protopline pro torkers. And give them a little tweeking.

Or do up a factory head. the factory 305/350 TPI heads (cast iron and aluminum) have lots of potential for improvement.

Vortecs are nice heads but really need to be matched with the Vortec intakes.

I might give them a shot. The only reason I considered the Vortecs is this is a 400 dollar intake (tpi) and the guy who had it before me had it on Brodix heads. He had seams welded to the outside to fit over the larger Brodix ports. That's why it's a 1206 size. I wouldn't want the head ports being smaller than the intake.

Company Name Manufacturer part number
Edelbrock Performer #2116
Edelbrock Performer RPM #7116
Edelbrock Performer RPM air-gap #7516
Edelbrock Performer Polished #21161
Edelbrock Performer RPM Polished #75161
Edelbrock Performer RPM air-gap Polished #75011
Edelbrock Victor Jr. Sportsman 2V #2912
Edelbrock Super Victor #2913

"Edelbrock
" Performer Multi-Point EFI #3505
"Edelbrock
" Performer Multi-Point EFI #3506
Edelbrock Performer RPM PRO-flow #3507
Holley WEIAND Stealth for port injection 9901-106
Holley WEIAND Stealth for port injection 9901-110
GMPP Cast iron q-jet 14097499
GMPP LT4 intake manifold adapted for vortec intakes but requires heads to be tapped for standard SBC 12550630
GMPP Ramjet intake 12489371
GMPP GM High Rise 12366573
GMPP TBI w/egr ready 12496821
GM OEM EFI 96+ 5.7L trucks
Hardin Marine Sport Series "SS" polished 620-52020
Hardin Marine Sport Series "SS" 620-52021
Power plus Cyclone 52007
Power plus Cyclone polished 52006
CFM-tech Cast iron high rise #400-VM
CFM-tech Cast iron high rise modified for more hp #400-VMP
CFM-tech Cast iron high rise #200-VM
CFM-tech Cast iron high rise #200-VMP
CFM-tech Aluminum high rise #ALI-970
CFM-tech Q-jet iron #CAI-960
SDPC TPI base TPI vortec base 12498060
Street & Performance inc RAM-PORT
Holley They have too many part numbers to list since they sell with injectors, for boast, hp range etc. Very complicated so just call them up and they can tell you what they've got.