Roller cam conversion Q's

[ElCaminoBill]

I'm looking to do a roller cam conversion. I have both a 350 and 305 from 89 trucks work with.

Besides the lifters, connectors, spider and cam, what do I need to install it?

I'm old school. Only dealt with flat tappet so far.

Please bring me up to speed on the tab in the timing cover to prevent the cam from walking.

Do you know of any roller cams with a mechanical fuel pump pushrod lobe? I'm looking to go pretty mild.

What about valve springs and rocker studs? Any mods needed there?

I seem to recall that the holes for the spider are drilled but not tapped. Is that correct?

Thanks for your help.

 

[mean78malibu]

When I went roller, I got the cam, springs, reinforced timing cover, and lifters. The reinforced timing cover has a steel tab welded on the outside so it has more holding strength to keep the cam from walking. My flat tappet had a cam walk button on it too, but i upgraded the cover with the roller. The springs are a necessity because of the higher lift usually, and that have more seat pressure. I did not go mild when I did the changeover though :roll: . Also, there are offset and nonoffset style roller lifters, I used the 'straight up' crower severe duty ones for my older small block.

One more thing, I switched to a bronze distributor gear with the roller cam.

 

[ScotSea]

If it is a block already set up to be a roller cam block, it is pretty easy. OEM uses a thrust plate that fits between the cam and the timing gear to locate the cam in position. Here is a picture of the plate from the Chevy High Performance magazine website.

http://www.chevyhiperformance.com/techarticles/148_0307_converting_hydraulic_roller_cam/photo_13.html

The whole article is not too bad to read either.

As far as cams that have the fuel pump lobe, I have a couple of stock TPI roller cams here, and they have the lobe, and the ZZ4 cam that sits here also has the fuel pump lobe.

Scot

 

[ElCaminoBill]

When I went roller, I got the cam, springs, reinforced timing cover, and lifters. The reinforced timing cover has a steel tab welded on the outside so it has more holding strength to keep the cam from walking. My flat tappet had a cam walk button on it too, but i upgraded the cover with the roller. The springs are a necessity because of the higher lift usually, and that have more seat pressure. I did not go mild when I did the changeover though :roll: . Also, there are offset and nonoffset style roller lifters, I used the 'straight up' crower severe duty ones for my older small block.

One more thing, I switched to a bronze distributor gear with the roller cam.

Is the reinforced timing cover a factory piece or aftermarket?

The lifters I will use are GM.

Oh yeah, the bronze dist. gear. Nor sure if my Mallory HEI has one.

Thanks!

 

[ElCaminoBill]

If it is a block already set up to be a roller cam block, it is pretty easy. OEM uses a thrust plate that fits between the cam and the timing gear to locate the cam in position. Here is a picture of the plate from the Chevy High Performance magazine website.

http://www.chevyhiperformance.com/techarticles/148_0307_converting_hydraulic_roller_cam/photo_13.html

The whole article is not too bad to read either.

As far as cams that have the fuel pump lobe, I have a couple of stock TPI roller cams here, and they have the lobe, and the ZZ4 cam that sits here also has the fuel pump lobe.

Scot

Good info, Thanks!

Looking over the info leads me to think that I'll need both the trust plat and roller-cam button along with a HD timing cover. Is that correct?

 

[mean78malibu]

I am not sure about the thrust plate, but my timing cover is an aftermarket piece. Not sure myself, I was a flat tappet guy before I had this motor built.

 

[ScotSea]

Good info, Thanks!

Looking over the info leads me to think that I'll need both the trust plat and roller-cam button along with a HD timing cover. Is that correct?

No, the OEM block just uses the thrust plate between the timing gear and the block. It controls movement both directions. No need for the button. If you are using a non-roller block you need the button.

Scot

 

[ElCaminoBill]

Scot,

Thanks for the clarification.

Bill