im getting ready to order parts for my buildup. i have the generic 350 and im going to convert it to a roller cam. what is the difference between solid roller and hydraulic roller. which would be better for the street? im going to get the retro conversion kit pushrods button and waterpump. i dont know if im going to keep my heads or get some 416's either way all i have to do to the heads is change springs for the conversion right? they will get new valves and screw in studs while they are there and a home p&p job.

 

Retrofit rollers are hardly worth if for the street, whether solid or hydraulic.

The difference is the the same as the difference between solid and hydraulic flat tappets. Solids are "solid", providing no cushion between the cam lobe and the pushrod/rocker - they are set up with a "gap" or "lash" between the rocker and valve stem when the cam is positioned so the lifter is on the heel (zero lift) of the lobe so the valve is assured to close completely. Hydraulic lifters "self adjust" with zero lash to allow the valve to close completely. The lifters tend to be heavier than solids, and will "pump up" and keep the valve open at high RPMs. Therefore, solids are typically used for higher reving engines.

For street use, hydraulics are preferred because solids require frequent adjustment. However, I have run a solid lifter cam on the street in the past (for about 2 years).

A good hydraulic flat tappet cam is what you should be looking for.

 

thanks 57. ill get the hydraulic flat tappet and save $500.

 

Which would be stupid.

Comp cams was nice enough to post dyno runs of their camshafts, both roller and flat tapet versions with everything else being equal. The roller setup is much more desired.

Theres a lot of places to cut cornors and save money. Cam is not one of them.
I'd throw the block away and start fresh before I'd go flat tapet..

Good news for you, many folks have modified the older blocks to accept OEM roller lifters. Its a very very simple mod.

-- Joe

 

Retrofitting hydraulic lifters is the expensive, and it's hardly worth it for a generic street build-up. For around $200, you can get a great flat-tappet cam, lifters, and timing set. A retrofit cam is going to be around $250, lifter around $250, and you'll need new pushrods.

If the block is set up for factory rollers, that's a different story (assuming you already have a set of lifters).

 

Roller tappets can be reused. If you scan eBay you may be able to find something, if you don't have any problems with that.

 

He should be able to get the pushrods, and lifters out of any of the 50 million 305 TBI motors sitting in the junkyard, or on ebay.

A custom grind cam from many "startup" grinders is $180 for roller. Check ebay.

Not to mention, he might find a use cam in the specs he wants for around $100

-- Joe

 

For a roller block yes. But if you are starting with a flat tappet, why waste the money of retro setup, when you can just get a good flat tappet cam and go from there.

 

my posts always stir things up.

 

See, I don't understand this thinking. You spend a few bucks collecting the parts, you make a modification to the block and your done.

Internal engine modifications always pay off on the end. Roller camshafts have numerous benefits.

-- Joe

 

If I were you, i'd do a little more research on this. There are folks on here who have done the modification to the block. Its easy.

-- Joe