The Leaky Head Thread
------------------------------INTAKE--------------------EXHAUST
----------------------Open---Close----Lift----Open----Close----Lift
Vendor Spec's: 1-BTDC 33-ABDC .353" 46-BBDC 2-ATDC .353"
Measurement: 1-BTDC 36 ABDC .353" 44-BBDC 2-ATDC .345
Bruno is going to call the vendor on Monday to see what they say, whether or not we need to change the cam timing. But, I doubt it.
Last edited by ctubutis; Mar 23, 2013 at 06:00 PM. Reason: fixed spacing for the table
Here s a link to the corral where I posted the cam readings that we took yesterday and I did get a response from Ed Curtis . You might want to read it to see if you make heads or tails out of it. Let me know if you cant view the thread and I will copy and paste it here :
Trying to Degree Ed Curtis Cam - Ford Mustang Forums : Corral.net Mustang Forum
The only thing he posted that applied was:
The .050" number should be the same as the cam card. If not... they should be off the same amount from each side and that's when you make adjustments on the timing chain.
Our numbers seem to say that the intake lobe is 3˚ wider than advertised and that the exhaust lobe is 2˚ narrower than advertised as well as being slightly shorter (.008"). That would mean that the intake lobe center is 1.5˚ retarded and the exhaust lobe center is 1˚retarded. (But someone needs to check my math.) I don't know what that means or does to the performance.
Goody_Seven says to advance the cam 2˚, but that would seem to be more than what is needed to compensate. Michael Yount may have given the best advice - a link to emailing FlowTechInduction.
Anyway, the shop will be open and the lights on - make yourselves at home. I'll see you after church.
In his defense, he probably deals with people who have no clue what they are doing so assumes the mistake is on their part, in the setup. But the fact that we got the intake opening, exhaust closing, and the intake max lift to be exactly what the spec's call for tells me that our setup is good. And, we got those #'s two times in a row. IOW, if half of the measurements are spot-on and if they are exactly the same two times in a row the setup is good. If we had gotten good #'s on the intake but bad #'s on the exhaust I would have said our exhaust setup was bad. Or vice versa. But nailing #'s on both lobes says the setup was good.
Perhaps he is used to customers griping when they don't even know how to set up, or take the readings in the first place.
Perhaps it is just his pat -and diplomatic- answer on the forums.
IDK...
But I'd think the lack of lift and duration on the exhaust side is only going to hurt, where the Ford port is disadvantaged already.
I know nothing about those heads you have installed.
Have you checked only the #1 cylinder?
A couple of degrees is not going to be evident from a casual visual examination of the cam itself.
Ford Trucks for Ford Truck Enthusiasts
We did only check #1. And, since the heads on well and truly on now checking another cylinder wouldn't be as easy.
Jim - Please check my reasoning and math. Do you agree that the intake lobe appears to be wider and the exhaust narrower than the spec's? And that the intake is retarded 1.5˚ and the exhaust 1˚? Any other observations? Would you advance the cam 1˚? (I think it should stay where it is, but I really don't know.) What are the advantages and disadvantages?
Trying to Degree Ed Curtis Cam - Ford Mustang Forums : Corral.net Mustang Forum
Gary. I have an old push rod we can modify to stick in the hole if we want to check it again with the head on.
Yes. I meant I know nothing about the numbers for the WPS heads.
The cam being reduced on the exhaust lobe might not be such a disadvantage in this case.
You can use almost anything as a pushrod, or even indicate off the top of the rocker arm if you like, it's not as if it is going to make a lot of difference other than the rocker moving sideways.
If the opening event is right I would leave it where it is.
And, I want to ask a question of this august group - is exhaust valve closing timing always stated in terms of After Bottom Dead Center? I ask because the spec's on the cam say the exhaust valve closes at "-2˚ ABDC". So, unless all cam exhaust spec's are stated in reference to ABDC it looks to me like a double-negative. Why not 2˚ BBDC?
Last edited by Gary Lewis; Mar 25, 2013 at 05:27 PM. Reason: Fixing stupidity. JASON, not James. Duh!
Jason and I tried to get the Bronco back together today. We spent most of the day today torqueing the intake manifold. We did get the pushrods, rockers and valve lash set today. The front cover went on and then I realized that I didn't put the little oil pan gasket niblets back on.So I decided that since the oil pan gasket has a leak in the rear that I would leave the front cover like it is and just drop the pan and re seal it next weekend.
We did get the water pump on as well, sand blasted the extremely fouled plugs and painted misc. parts too. I think next weekend will be the last of the work days as far as planning to have it back together then.
To say that there was enough RTV would be a bit of an understatement. And, it wasn't only on the front and rear webs that the goo was used. Remember, this is a high-dollar build, what with roller rockers and lifters, special cam, aftermarket heads, ARP fasteners for both the heads and the intake, high flow water pump, etc. Except for the intake manifold, which is well used and has significant corrosion around the water passages. So, lots of goo was used around them to ensure no water leaks.







