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Head Questions part 2

  • Thread starter Thread starter ky_kneedragger
  • Start date Start date Mar 16, 2008

ky_kneedragger

Member
Jan 7, 2008
58
0
6
ky
Mar 16, 2008
#1
  • Mar 16, 2008
  • #1
Well i finally pulled the head from my '00 gt and thought i had a bent valve,turns out it had a small piece of metal holding it open!!! It all started when i bought a set of comp cams ( #xe278ah ) i dove into it all without much research and have had problems ever since. when i pulled the timing cover i noticed that my chains had worn through the guides and into the tensioner, so i replaced that **** and put it all back together. When i fired it up it had a bad rattle so I had a mechanic from a ford dealer stock and listen to it. He told me it was outta time,so i took it all back apart and read several different guides on timing it! After i done that it still had a rattle and a noise that sounded like a sewing machine,which rep from comp cams said was normal for them.so i drove it around for a while ( easy )and ended up gettin' called out by a slomaro.

By that time all the noises went away and i drove it for a day or 2 and then it developed a miss followed by a rattle ( sounded like a pushrod motor with a loose rocker arm )and after a few seconds the miss went away along with the noise!!! then it started doing that on a regular basis no matter how i was driving it,i figured it was a weak lifter getting compressed then pumping back up so i replaced all of them.after i got it together again i drove it about a mile then the same **** happened except this time the rattle went away but the miss didn't!!!!well i figured it was my springs,so i tried to put air into the cylinder so i could change the springs and on the # 5 cylinder the exhaust valve was stuck open and the rocker was laying in the bottom of the head???? I assumed i had a bent valve, Wrong!!! i pulled the head off tonight and thats when i found the metal holding it open.and i notice that all the pistons on the driver's side had hit the valves at some point. A could the factory springs have caused this or was it from when it was outta time???

I'm sorry for writing so much but i figured it was the best way to get the right answers. If anyone has any idea's of what my next move should be please let me know!!!i thought about just checking the valve and making sure it wasn't hurt and just put it all back together with my new springs...: crapola:SNSign:
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
4
39
UCSD/La Jolla
Mar 16, 2008
#2
  • Mar 16, 2008
  • #2
you should have told us this from the get-go. Firstly 278ah's are stage III cams and REQUIRE aftermarket springs. Most even recommend aftermarket heads due to their rpm flow range. Even with the right springs you need to degree these cams, not just time them to the crank. EVEN then these cams have been known to have PTV (piston to valve) contact problems in some peoples cars. If you can take pictures im sure we can tell you what you need to scrap
 

ky_kneedragger

Member
Jan 7, 2008
58
0
6
ky
Mar 16, 2008
#3
  • Mar 16, 2008
  • #3
well the guy i got them from said he ran these in stock heads and bottom end.i have comp cams springs,i was in the process of putting these in..too late no i guess,but uh i think maybe the last time i timed it that it was maybe still out b/c i figure that the noise i heard b4 was the valves hitting and after they made a place in the pistons is why it all finally got quiet..I'm gonna go with a lil bit thicker head gaskets whenever i put it back together..I'll try to get some pics of it and post them on here...like I said the pistons have a few pits in them from pieces of metal blowing around the cylinders..i have another set of heads that i got from a 5.4 the other day...I might just go ahead and put those back on it due to shortage in funds..
 

ky_kneedragger

Member
Jan 7, 2008
58
0
6
ky
Mar 16, 2008
#4
  • Mar 16, 2008
  • #4
CobraRed_96_GT said:
you should have told us this from the get-go. Firstly 278ah's are stage III cams and REQUIRE aftermarket springs. Most even recommend aftermarket heads due to their rpm flow range. Even with the right springs you need to degree these cams, not just time them to the crank. EVEN then these cams have been known to have PTV (piston to valve) contact problems in some peoples cars. If you can take pictures im sure we can tell you what you need to scrap
Click to expand...
also would i have to get adjustable cam gears to degree the cams??
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
4
39
UCSD/La Jolla
Mar 16, 2008
#5
  • Mar 16, 2008
  • #5
ky_kneedragger said:
also would i have to get adjustable cam gears to degree the cams??
Click to expand...

not required i dont think, although stock sprockets weaver 5 degrees or so
 

mogs01gt

Founding Member
Jul 22, 2002
3,113
30
119
Ohio
Mar 18, 2008
#6
  • Mar 18, 2008
  • #6
You need valve reliefs to run those cams or you timing was off. I think both happened.
 

ky_kneedragger

Member
Jan 7, 2008
58
0
6
ky
Mar 18, 2008
#7
  • Mar 18, 2008
  • #7
mogs01gt said:
You need valve reliefs to run those cams or you timing was off. I think both happened.
Click to expand...
after i got looking at it and thinking bout the money i have wasted so far!!!! i'm gonna do some cutting on the pistons and make room for the valves, the car ran too good and started great for it to have been out of time. i done some cutting on a 5.0 i had b/c i was worried about valve clearance due to heads being shaved so much the intake valve was sticking out past the combustion chamber!!!but anyway i've ordered the ford racing head changing kit for 117.00 from summit!!i wish i had some bbk LT headers put on b4 i reinstalled the heads but i dont have that much money left...
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
4
39
UCSD/La Jolla
Mar 18, 2008
#8
  • Mar 18, 2008
  • #8
or sell/trade those 278's for cams you can actually benefit from and you wont have those clearance problems to begin with. Not sure you need valve reliefs anyways, just risky on these engines. You need a tune either way
 

mogs01gt

Founding Member
Jul 22, 2002
3,113
30
119
Ohio
Mar 18, 2008
#9
  • Mar 18, 2008
  • #9
ky_kneedragger said:
after i got looking at it and thinking bout the money i have wasted so far!!!! i'm gonna do some cutting on the pistons and make room for the valves, the car ran too good and started great for it to have been out of time. i done some cutting on a 5.0 i had b/c i was worried about valve clearance due to heads being shaved so much the intake valve was sticking out past the combustion chamber!!!but anyway i've ordered the ford racing head changing kit for 117.00 from summit!!i wish i had some bbk LT headers put on b4 i reinstalled the heads but i dont have that much money left...
Click to expand...
If it ran well, you probably had them advanced too far.
 
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