HOLY CAM!

IDIoit

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It should be said that if your going to install the typ 4 cam you have to check your clearances, piston to valve and preload on your lifters.
Awhile back I had posted abt. a tick in my motor and the consensus was a bad lifter.
What I found was zero preload on my lifters, that was my tick, I had a feeling I should pull the heads...................

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all the pistons had valve imprints.

This obviously could have been a disaster if I kept running it.

My motor falls within factory specs. so don't assume you can just slide this cam in and run with it, your going to have to do a bit more work.
I'm not an isolated case, they're are others that had the exact same problem.

compression, and springs need to always be addressed when installing a bigger cam.
to do it right, would be to use machinist clay on the top of the pistons completely assembled, and rotated to find piston to valve clearance.

its not the cam that's incorrect, its the install.
 

77f250diesel

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Your absolutely correct !
My point was that clearance needs to be checked, not who's fault it was.
 

IDIoit

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i was tryin to find a polite way of saying if you kiss your valves, get ready for the machine shop to make love to you..lol
wasn't tryin to point fingers..:D

and for you automatic freaks, stall converter could play a part as well
 

jetfly12

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What are the steps in the install to ensure that you will have valve clearance?
Or what reasons why it won't clear and what has to be done to prevent contact?
 

Dsl_Dog_Treat

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IMHO, running high rpms and floating valves may have been a contributor there as our IDI lifters are hydraulic. That's a first to see a typ4 cam having valve to piston contact.
 

IDIoit

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What are the steps in the install to ensure that you will have valve clearance?
Or what reasons why it won't clear and what has to be done to prevent contact?

you need to understand that different engines have different deck heights, piston protrusion, and valve recess.
this all plays a part in how much you can open a valve. cam timing is not adjustable like a gasser on these engines.
these are all vital pieces to the puzzle.
you should also have the correct spring rating on your valve springs, or you will float a valve.
and a floating valve is more susceptible to hitting a piston through its travels.

i wish it was as simple as slapping a cam in. but it just simply isn't that.
valves and pistons need to be measured, and good springs need to be had.
another good idea is cutting the pistions .010 smaller for a piece of mind, and run more boost :D
 

77f250diesel

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IMHO, running high rpms and floating valves may have been a contributor there as our IDI lifters are hydraulic. That's a first to see a typ4 cam having valve to piston contact.

In my case, highly unlikely.
Along with the cam, new lifters and 910 springs shimmed.
Those imprints are more than a "kiss", their more like a slap and I find no reason to twist the motor past 2300-2400 rpm.

It's not a 1st., do a search for motor ticking, rebuilt motor ticking and you'll find others with the same problems.
Also, keep in mind I came to the conclusion that the ticking I was hearing was the zero preload on the lifters, so how many people are out there who made the same mistake I did, not checking clearances, who's valves are kissing the pistons ?

Come to your own conclusion, I posted so others can avoid this mistake.
 
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IDIoit

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i do hope people read this and take the necessary precautions.
77F250, you are completely correct, youre not the first, and you certainly wont be the last.
altho i would like to think everyone and their mother will read this and do their homework.
its basic machining fellas, not rocket science.

if you sit down, have all of your information, and do the homework.
you will be just fine.
the absolute crappy part of all of this is: the cam profile is more top secret than Hillarys deleted e-mails.
you need to get the cam and profile it for yourself.
it is proprietary. and IMO is not for a novice.

the major point of this post is:

WHEN DONE CORRECTLY, THIS CAM F'ING ROCKS!
compared to the stock cam.
if i do another IDI, i may try a different grind,
 

jetfly12

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you need to understand that different engines have different deck heights, piston protrusion, and valve recess.
this all plays a part in how much you can open a valve. cam timing is not adjustable like a gasser on these engines.
these are all vital pieces to the puzzle.
you should also have the correct spring rating on your valve springs, or you will float a valve.
and a floating valve is more susceptible to hitting a piston through its travels.

i wish it was as simple as slapping a cam in. but it just simply isn't that.
valves and pistons need to be measured, and good springs need to be had.
another good idea is cutting the pistions .010 smaller for a piece of mind, and run more boost :D

All make sense! I am wanting to do the cam and the thing holding me back is I don't want to deal with cam bearings, how many here reuse the bearings? Sounds like you can't slide by reusing the hydraulic lifters, where does one picks some new ones at?
Thank you
 

icanfixall

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The hydraulic lifters used in our idi engines can be found is many other engines.. Like nearly every power stroke or Hummer engine. Even some gasser engines use the same lifter. Because our lifters are a hydraulic roller lifter we normally do not need to change lifters when a cam is replaced. They really are not expensive but you can reuse them and not have cam issues. nothing is rubbing the cam. just a roller rolling on the cam.
 

icanfixall

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It should be said that if your going to install the typ 4 cam you have to check your clearances, piston to valve and preload on your lifters.
Awhile back I had posted abt. a tick in my motor and the consensus was a bad lifter.
What I found was zero preload on my lifters, that was my tick, I had a feeling I should pull the heads...................

You must be registered for see images attach


all the pistons had valve imprints.

This obviously could have been a disaster if I kept running it.

My motor falls within factory specs. so don't assume you can just slide this cam in and run with it, your going to have to do a bit more work.
I'm not an isolated case, they're are others that had the exact same problem.

SAd to see this happening but I need to ask about falling in the factory specs. What was the valve recess in the heads. What is the head thickness. Was a valve job done. What was the piston protrusion from the cylinders. and finally what was the tested valve spring pressure. We use the same valve spring in both the intake and the exhaust valves and they are something like 110 lbs closed. Its plenty of work to get all the questions answered but doing so keeps contact from happening. I see just one valve contacting the pistons. If valve work was done to the heads what was the installed height of these valves that contacted the pistons.
 

jetfly12

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In my case, highly unlikely.
Along with the cam, new lifters and 910 springs shimmed.
Those imprints are more than a "kiss", their more like a slap and I find no reason to twist the motor past 2300-2400 rpm.

It's not a 1st., do a search for motor ticking, rebuilt motor ticking and you'll find others with the same problems.
Also, keep in mind I came to the conclusion that the ticking I was hearing was the zero preload on the lifters, so how many people are out there who made the same mistake I did, not checking clearances, who's valves are kissing the pistons ?

Come to your own conclusion, I posted so others can avoid this mistake.

The hydraulic lifters used in our idi engines can be found is many other engines.. Like nearly every power stroke or Hummer engine. Even some gasser engines use the same lifter. Because our lifters are a hydraulic roller lifter we normally do not need to change lifters when a cam is replaced. They really are not expensive but you can reuse them and not have cam issues. nothing is rubbing the cam. just a roller rolling on the cam.

good to know! thank you. I want the cam, as i intend to tow often. Over I70 in colorado!
 

FORDF250HDXLT

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so now that the engine isn't still set at 3 BTDC,the cam still hauls ars over stock at 8 +/- 2 BTDC too hey?
 

FORDF250HDXLT

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so since i don't think the T-cam has any higher lift,im trying to figure out why someone would end up with interference.do you get a cam card with the cam showing to offset the teeth by a degree to help with valve interference timing issues? if not,one has to think,those who ran into issues would have run into the same problem had they used an oem cam no?:dunno
 

IDIoit

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so since i don't think the T-cam has any higher lift,im trying to figure out why someone would end up with interference.do you get a cam card with the cam showing to offset the teeth by a degree to help with valve interference timing issues? if not,one has to think,those who ran into issues would have run into the same problem had they used an oem cam no?:dunno

a cam card does not come with this cam.
and i do believe it does have more lift.
its been a while since i measured it, and i cant remember.
but lets say for arguments sake, that the lift is identical.
the duration and the separation of the lobes are indeed different.
which puts the valve in places a stock cam would not during its rotation.
 
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