flat tappet.
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Originally Posted By: toyota62
http://z.about.com/d/autorepair/1/0/s/S/42124617.gif
is this flat tappet?
My guess is that`s a roller cam,right?
http://z.about.com/d/autorepair/1/0/s/S/42124617.gif
is this flat tappet?
My guess is that`s a roller cam,right?
Originally Posted By: c3po
I think that they are roller cams, I am sure that GM went to rollers in 1987, and I would think that Toyota did too.
I would Google Flat Tappet Cams and you will find out all of the info you need.
Close. The Buick V6 was still using flat tappets in '87 but went roller the following year in FWD form.
I think that they are roller cams, I am sure that GM went to rollers in 1987, and I would think that Toyota did too.
I would Google Flat Tappet Cams and you will find out all of the info you need.
Close. The Buick V6 was still using flat tappets in '87 but went roller the following year in FWD form.
You can't really tell by looking at the cam as they're both cam shaped lol.
The roller cams usually have a more aggressive ramp so the nose of the lobe will look a little flatter. Still can't always tell by eyeballing it.
Obviously the lifter is what you want to look at. The flat tappet (or lifter) has a flat bottom (the portion that rides on the cam) and the roller lifters have a roller built in. For this reason the roller lifter must be kept from rotating while a flat tappet lifter is supposed to rotate in it's bore. There will be extra hardware to keep the roller lifters straight in the bore.
The roller cams usually have a more aggressive ramp so the nose of the lobe will look a little flatter. Still can't always tell by eyeballing it.
Obviously the lifter is what you want to look at. The flat tappet (or lifter) has a flat bottom (the portion that rides on the cam) and the roller lifters have a roller built in. For this reason the roller lifter must be kept from rotating while a flat tappet lifter is supposed to rotate in it's bore. There will be extra hardware to keep the roller lifters straight in the bore.
The diagram shows what would be called a "flat tappet" because it has no roller between the cam and lifter.
the lifter on the right is "flat" while the one on the left is a "roller"
the lifter on the right is "flat" while the one on the left is a "roller"
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Originally Posted By: tom slick
The diagram shows what would be called a "flat tappet" because it has no roller between the cam and lifter.
the lifter on the right is "flat" while the one on the left is a "roller"
And note the flat spot near the top where the hardware attaches to keep it from rotating. Nice illustration.
The diagram shows what would be called a "flat tappet" because it has no roller between the cam and lifter.
the lifter on the right is "flat" while the one on the left is a "roller"
And note the flat spot near the top where the hardware attaches to keep it from rotating. Nice illustration.
Actually the "flat" part is just a little domed ,so the cam lobe, will turn it slightly in the lifter bore as the engine runs.
It is the high performance factory and aftermarket cams/lifters that can need extra help with break in.
In a valvetrain, you have a roller or a flat tappet, whether overhead cam or pushod.
In a valvetrain, you have a roller or a flat tappet, whether overhead cam or pushod.
Toyota's ARE NOT roller valvetrains. They are flat tappet shim over bucket or bucket/lifter type without roller lifters.
The valve springs will be wimpy soft pressures enough to control the valve from bouncing and floating.
In my old pushrod motor in my 1965 beetle (11's in the 1/4 mile)I use chevy springs. Aprox 150lbs seat pressure and aprox 380 lbs at the nose of the cam on full lift. Using tool steel lifters requires NO breakin on a virgin engine.
For over head cams you have NOTHING to worry about.
In my old pushrod motor in my 1965 beetle (11's in the 1/4 mile)I use chevy springs. Aprox 150lbs seat pressure and aprox 380 lbs at the nose of the cam on full lift. Using tool steel lifters requires NO breakin on a virgin engine.
For over head cams you have NOTHING to worry about.
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