You guys know the drill...

It starts with something like...I think I'll replace my water pump...well, the timing set is right there, might as well replace that...if I'm gonna do that might as well replace the thermostat...gotta pull the plenum, might as well change some gaskets...hey! there's the cam...might as well...you know...water pump to overhaul; that whole chestnut.

So, I'm talking with a friend (Mr. Goodwrench) of mine and he says "go roller". I like his thinking. And he's done the conversion on his truck and I like it! Has anyone here converted a L98 to a HYD roller cam? This sounds like so much fun I can't wait to get started. A 52 mm TB sounds like a good idea too. We don't have vehicle inspection here anymore so it's back to the good ol' days...dual exhaust!

Anyways...any thoughts? Bear in mind I got this Vette for me to play with so suggestions of buying an engine or paying someone else or typing just to see your fingers move can move along. :seeya

 

With a non-roller block I might put in an agressive flat tappet cam, have the heads worked and the push rod holes enlarged and then go with 1.7:1 RRs to get some additional valve intensity.

 

Yeah...but that's you.

I won't know for sure until I pull the intake and look at the lifter bosses. But according to my friend, that works for a local GM dealership that's done this conversion, it's little more than a drop in. He did his conversion on his truck block with no machine work, just lotsa parts. The throttle response is right now! GM is all about assembly line and one size fits all...we've all found wires for options that aren't on our cars, and bolt holes and such for things that aren't there either...wouldn't surprise me to find that the lifter bosses are ready.

 

Well it they are then all you would need is the spiders to bolt in that hold the lifters from rotating.

 

That's what I'm hoping for. The rest should be cake from there. Push rods, self centering rockers and I'm gold.

Whaddaya think...30, 40 even 50 hp gain? Losing all that friction will be significant by itself.

 

It is easy to change to a roller like your friend say's just takes the right parts.
You don't have the thrust plate like the later blocks so you need to stop the cam from walking most use a aluminum button in front of the cam this is the cheap way but the stock timming cover will move from the pressure and allow the cam to move also. I installed a torington bearing behind the cam gear and then used a cast aluminum timming cover with a bearing built onto an adjusting screw this allows you to adjust the free play on the cam. you have to use special roller lifters with the bar on them to keep them from turning. With a roller cam you cam run a much more aggressive profile cam and still maintain good idle. GM and Ford both use these in production engines because they are vastly superior to the flat tappet cam. This subject came up recently some think the roller is not worth the money but all major manufactures disagree because they use them. If you are trying to build something cheap the flat tappet is less but if you want performance and can afford it the roller is the way to go. Also consider the roller rockers
Much less friction. Look at it this way would you rather push a car with wheels on it or drag it with out the wheels. It's all about friction.

 

I haven't heard a bad thing about roller cams. Same duration - sharper angles = more airflow without killing the idle. All it takes is money.