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Discussion Starter · #1 ·
I have installed an E-303 cam in a 1998 ford explorer 5.0 engine. I am putting the engine in a 1990 mustang gt. I put a dial indicator on the pushrod and am only getting 298 lift. the cam is suppose to do a 498 lift with 1.6 rocker arms. Any help with this?
 

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If you are putting the dial indicator on the pushrod, then you are measuring lobe lift, not gross valve lift.

Using the old calculator, lobe lift on an E-303 should be somewhere around .311, give or take. Your measurement is not too far off, but not exact.

Make sure that the dial indicator is as straight as possible on the end of the lifter, aligned as well as you can. Also ensure that you have everything nice and tight so you don't get any movement and error in the readings.

Also, if you are not using a solid lifter (you can reverse the guts in a hydraulic and turn it into a solid) then you will have some error as well since the plunger will move. Hence the term hydraulic. :D
 

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Discussion Starter · #3 ·
so how do I know if I'm getting the correct lift. It calls for 498 lift on the intake and exhaust with a 1.6 rocker arm. Thats what I have. What do i need to check or do?
 

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1990saleen said:
so how do I know if I'm getting the correct lift. It calls for 498 lift on the intake and exhaust with a 1.6 rocker arm. Thats what I have. What do i need to check or do?
The odds of a mass-produced cam like the E-303 being off are probably not that great, so the odds are that there is a small amount of error in your measurements. But, like I said, the amount you are off is not that great. Looks to me like you are only around a tenth of an inch off or so.

I'd start with getting an old roller lifter, swapping the guts inside of it around, and measuring again. More than likely, you will be closer that way. Pic below.

 

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The lift specified on a cam is the VALVE opening/lift. Remember that the rocker increases the lift at the valve due to the ratio being greater than 1:1....either1.6 or 1.7 rockers. Put your dial indicator or the valve and measure the valve lift when the lifter is at .050 lifter rise...it should be what is advertised.
 

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FYI ( forgot to mention in my earlier response above ):
Your LIFTER measurement of .298 multiplied by your 1.6 rocker ratio equals approx .477, so you're close. As JCM3 indicates, recheck your dial indicator measurements and you'll likely find you're cam is producing the lift specified.
 
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