Target Master Motor

[toolboxchev]

I have a chance to pick up one of these in the Roller Cam version. Does anyone know if these were drilled for the mechanical fuel pump?

It came out of a 98 Tahoe/Burb application. Spoke to the gentleman today and there is no VIN code on the pass deck.

[Ziegelsteinfaust]

The Vortec roller engines are hit or miss with the fuel pump rod hole drilled. Atleast from the factory in the handful I have had my hands on.

I got a 97 vintage 305 Vortec for my C20, and it did not have the hole drilled. You could see where the hole should be, but the engine was a runner. So I left it alone, and used a electric pump.

My friend's Suburban blew its factory-installed engine, and when we pulled it part. It had the hole drilled. Well the block got trashed, and we went looking for a rebuild able long block. Well the replacement was drilled too, and I took it to JMS for him. I asked them, and they said quite a few have it drilled already.

The story I heard is there is no rhyme or reason to the hole being there. The hole is for old engines set ups, and they must of been thrown in when they just needed them for new style production.

In my engine pile I have a brand F 4.6 aluminum 2V I found in a 2003 F150. I mean I found it in there myself, and bought it. Supposedly it was a Explorer only engine, but I got my in a F150.

If you do want to use a fuel pump rod if the hole is there. You can not use a old school rod. It supposedly has to be roller cam compatible.

[truckster]

If there's a block off plate, it's drilled and tapped. If you use a mechanical fuel pump with a roller rocker you'll need a pushrod with a bronze tip. That's the setup I have.

[Captainfab]

I have about 6 L31 Vortec 350's and none are machined for a mechanical fuel pump. I have seen a few '95 and earlier blocks that have the provisions for the factory roller cam and have the machine work done for a mechanical fuel pump.. Keep in mind that not all factory roller cams have the mechanical fuel pump lobe. The L31 cam does not.

[toolboxchev]

Last 2 bolt roller block I got a hold of had the block off plate. It was out of an 88 Camaro, yet hole there and not bored out.

I got rid of that 2 bolt block for obvious reasons.

[toolboxchev]

Originally Posted by Captainfab

I have about 6 L31 Vortec 350's and none are machined for a mechanical fuel pump. I have seen a few '95 and earlier blocks that have the provisions for the factory roller cam and have the machine work done for a mechanical fuel pump.. Keep in mind that not all factory roller cams have the mechanical fuel pump lobe. The L31 cam does not.

Thanks for that point on the L31, been thinking going that route. If I really make the plunge I am going with a ZZ4 short block assembly.