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Flat tappet to roller tappet Q

1074 Views 7 Replies 6 Participants Last post by  Stinger
I just changed my oil today and read aprx 30 pages by the good Dr. on the topic to be sure I picked up the correct oil. It seems to me there are some issues with flat tappets, my question is would it be worth swapping in roller tappets? Is this possible? I try to stay out of the motor and tranny as much as possible, but I am kicking around the idea of picking up a 4.0 block and building up a stroker in the garage over the winter. I dont know if tappets can be swaped. Also is the 4.0 solid flat tappets or hyd flat tappets?
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We have hydraulic flat tappets in the 4L

I've got a lifter tick and was considering a switch to rollers in the future. Very few choices to convert- none of them cheap- 1400 in parts.

505 performance has a few kits, dont know anything about them.

A custom grind from Comp Cams or Crane, they both have retro-fit hydraulic roller lifters for AMC V-8 which are the same part numbers in flat tappet, probably have to check oiling feeds and such to see if they will work.
Interested to see if anyone else has done or is contemplating a switch.
SteveVB said:
We have hydraulic flat tappets in the 4L

I've got a lifter tick and was considering a switch to rollers in the future. Very few choices to convert- none of them cheap- 1400 in parts.

505 performance has a few kits, dont know anything about them.

A custom grind from Comp Cams or Crane, they both have retro-fit hydraulic roller lifters for AMC V-8 which are the same part numbers in flat tappet, probably have to check oiling feeds and such to see if they will work.
Interested to see if anyone else has done or is contemplating a switch.

Me too. This sounds interesting.
When I was looking at performance upgrades Doc suggested that changing the cam out was probably the best upgrade we could do on the late model 4.0L. I wonder how much a full roller valvetrain would be worth in the power department?
Hesco is about your best source for info and parts with the internals of a 4.0 engine.
It's a toss up to me. Change to rollers and void the warranty, keep the flats and hassle with the warranty.
What is this "warranty" word I have been hearing lately? I am sorry I don't speak spanish
Rockunlimited2 said:
What is this "warranty" word I have been hearing lately? I am sorry I don't speak spanish
:rotflmao: :rotflmao: :rotflmao:
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