[fastest95stang]

what is the difference between a flat tappet lifter and a hydrolic roller lifter.i want to put this comp cams cam kit in my 89 lx but i want to make sure it will work...it says it is a flat tappet lifter style and says it will work with my car but i was just wondering the differences between the 2...also what is the highest lift that a stock 5.0 will except...this kit has a lift of .512/.512...will that work????plz help

[murdock2112]

Im not sure about the difference cause ive only ever used roller cams but, I think that its just has to do with the lifter. and yours being an 87 your car already has roller lifters. As for the lift I have an F-303 cam that has .512 lift and I havent had any problems. Sorry I couldnt be more help.

[wayne94mustang]

roller lifters rob way less power since they roll over the cam instead of rubbing on it

[fastest95stang]

ok well i think i figured it out...so anyway i am looking at the ford racing roller lifters for around 104.00 and i was wondering if anyone could tell me if these are a direct replacement for the ones that are in there now??...i mean just drop them in...???...i also plan on getting a comp cams roller cam shaft also...i was looking on summits site and they said that minor block work to solve clearencing issues could be possible with these lifters...so again do i have to worry about doing any of that stuff??

[roughneck9725]

a flat tappet cam has no roller under the lifter. It rides on the lobe directly. The opening ramps on the lobes cannot be as aggressive on a flat tappet or the tappet will gouge the cam lobe. Because of this, a roller profile is generally more aggressive and will produce more power even with the same "advertised" numbers. Also, there is the benefit of less friction due to the rollers. A cam button has to be used with a roller cam (HO 5.0's have one factory if they have a roller cam) to keep the cam from walking. A flat tappet keeps the cam in the block by have a slight angle on the lobes that the tappets ride on, which continuously keep it pushed in. Hope this helps a little.