85_sc

Can a lt1 intake be used on vortec heads if it can it would be alot cheaper that the scoggin dickey intake base.

John Millican

iTrader: (1)

No, the ports don't line up at all. Not even close.

This information is in my FAQ on my website too!

jmd

iTrader: (4)

The Vortec ports are raised from Gen I SBC head ports about a tenth of an inch. The Vortec heads are based on the LT1 heads.

As far as the bolt pattern, the LT1 intake has all 12 bolts at the same angle as the middle 4 on an 87-up intake.

Ports would be good, bolt angles & locations would be way wrong. Then again so would an LT1 intake on an L98, but the tide of lemurs keeps flowing.

John Millican

iTrader: (1)

Again, the ports are not even close. Here's a cutaway picture of a carbed SBC intake on a (Fastburn) Vortec head.
Fastburn heads were drilled for both patterns.

I'd give credit to the picture taker but I don't know who took it.

turtle

I'd have to take john's word on it gosh darn it. he's the one modifying lt1 intakes to fit sbc engines and hoping to make a little of course. now if he could with a reasonable amount of effort make an lt1 to fit vortec heads i am sure he would and has taken a look at it since vortecs are a very hot head on engine build ups these days.

jmd

iTrader: (4)

John, that would be valid if the LT1 ports were not raised at all compared to a Gen I SBC.

Steve91Z28 L98

The LT1 intake will not line up at all with the Vortec ports. You will also have a major vacuum leak as shown in the picture John posted. If you want, you can go the route I took and use an LT4 intake. You will have to get the Vortec heads drilled for a standard bolt pattern to make it bolt up though. The Vortec bolt holes are way too high up to work. I used the Fastburn heads which already come with the standard bolt pattern. You can again see the differences in the bolt holes in the earlier posted pic. The ports on the LT4 intake match up almost perfectly to the Vortec/Fastburn ports using a Felpro 1255 gasket. I had to do some very minor port matching to the top of the LT4 ports to make it perfect. I only had to remove about 1/8" off the top. Other than that, the rest of the modifications are exactly like the LT1 intake swap.

I've always wondered though, if you are going to get the Vortec heads drilled already, why not see if you can have the LT1/LT4 bolt pattern drilled in them. That way you wouldn't have to modify the bolt holes on the intake. I would definitely do some test fitting before I actually had the intake drilled but it should make the swap go a whole lot smoother. I'm still waiting to see if someone attempts this.

I'm extremely happy with how mine turned out. The motor will now pull very strongly to 6500+ rpms. I'm still trying to get the tuning dialed in and then I'll be off to my first dyno and track runs.

Steve91Z28 L98

By the way, in that picture John posted, that is the FelPro 1255 gasket. As you can see it is thicker than a standard gasket which I believe helps the ports be so close. The LT4 intake/heads combination was designed with raised ports just like the Vortec/Fastburn. Obviously GM knew what they were doing seeing how the LT4 was such a strong motor and designing the Vortecs with the same idea in mind. And we all know what those heads are capable of out of the box.