Problems, problems, problems......
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Compression test
Did a compression test this afternon just to see what it produced. Good pressure on all. Is this about normal for a 95,000 mile motor?
#1- 210
3- 210
5- 200
7- 200
#2- 220
4- 225
6- 235
8- 225
#1- 210
3- 210
5- 200
7- 200
#2- 220
4- 225
6- 235
8- 225
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,008
From: Texas
Did you check the wires and plugs? Your dyno graph has "ignition problem" written all over it.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
The plugs...........not to good. Most were really dark but not like oil dark just didn't appear to be burning right. A couple were light on one side and darker on the other.
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
I know you did it right, but when the camshaft gears are installed, it should look like this. Notice where the pin is. The gears on the cam and crank have the dot aligned with each other.
When you put your Opti on, you have to really really try to get the dowel pin into the other holes within the back of the Opti. I am not saying it isnt possible, especially if the dowel pin is a little smaller than normal due to machining, but not very likely. Retrace your steps on the Opti and see if she is plugged in right, plug wires on correct and also check that your injectors are plugged into correct injector. OBD2 cars usually give a code if they are plugged in wrong.
Also, what do the exhaust headers look like when running at night with no lights on? Are they cherry red anywhere?
When you put your Opti on, you have to really really try to get the dowel pin into the other holes within the back of the Opti. I am not saying it isnt possible, especially if the dowel pin is a little smaller than normal due to machining, but not very likely. Retrace your steps on the Opti and see if she is plugged in right, plug wires on correct and also check that your injectors are plugged into correct injector. OBD2 cars usually give a code if they are plugged in wrong.
Also, what do the exhaust headers look like when running at night with no lights on? Are they cherry red anywhere?
Pro
Joined: Aug 2004
Posts: 549
Likes: 13
From: Richmond VA
I would use a laser thermometer to check the header tubes when running. If all temps are close it is not your plug wire setup. If one or more are off then you know those are the ones not running correctly. If all are close to the same look at PCM and tune via some datalogs first.
Last year I had to do this to find which 2 wires were flipped, motor was hot so did not want to trace the wires.
Last year I had to do this to find which 2 wires were flipped, motor was hot so did not want to trace the wires.
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Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I know you did it right, but when the camshaft gears are installed, it should look like this. Notice where the pin is. The gears on the cam and crank have the dot aligned with each other.
When you put your Opti on, you have to really really try to get the dowel pin into the other holes within the back of the Opti. I am not saying it isn't possible, especially if the dowel pin is a little smaller than normal due to machining, but not very likely. Retrace your steps on the Opti and see if she is plugged in right, plug wires on correct and also check that your injectors are plugged into correct injector. OBD2 cars usually give a code if they are plugged in wrong.
Also, what do the exhaust headers look like when running at night with no lights on? Are they cherry red anywhere?
When you put your Opti on, you have to really really try to get the dowel pin into the other holes within the back of the Opti. I am not saying it isn't possible, especially if the dowel pin is a little smaller than normal due to machining, but not very likely. Retrace your steps on the Opti and see if she is plugged in right, plug wires on correct and also check that your injectors are plugged into correct injector. OBD2 cars usually give a code if they are plugged in wrong.
Also, what do the exhaust headers look like when running at night with no lights on? Are they cherry red anywhere?
I know the dots are correct but I swear I thought that pin was on the other side. I probably turned the crank though after I installed the chain. That wouldn't matter would it? The FSM says to have #1 at TDC when installing the opti. Of coarse I read that after I put it on. I didn't think it mattered. I'm positive I got the pin in the correct slot. I've read to many opti threads not to do that. I'll look at the headers tonight. I have another PCM coming probably tomorrow with my tune and a corrected AFR. If that doesn't fix it I guess it's time to start taking things back off.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I would use a laser thermometer to check the header tubes when running. If all temps are close it is not your plug wire setup. If one or more are off then you know those are the ones not running correctly. If all are close to the same look at PCM and tune via some datalogs first.
Last year I had to do this to find which 2 wires were flipped, motor was hot so did not want to trace the wires.
Last year I had to do this to find which 2 wires were flipped, motor was hot so did not want to trace the wires.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Thanks again Steve
I know the dots are correct but I swear I thought that pin was on the other side. I probably turned the crank though after I installed the chain. That wouldn't matter would it? The FSM says to have #1 at TDC when installing the opti. Of coarse I read that after I put it on. I didn't think it mattered. I'm positive I got the pin in the correct slot. I've read to many opti threads not to do that. I'll look at the headers tonight. I have another PCM coming probably tomorrow with my tune and a corrected AFR. If that doesn't fix it I guess it's time to start taking things back off.
I know the dots are correct but I swear I thought that pin was on the other side. I probably turned the crank though after I installed the chain. That wouldn't matter would it? The FSM says to have #1 at TDC when installing the opti. Of coarse I read that after I put it on. I didn't think it mattered. I'm positive I got the pin in the correct slot. I've read to many opti threads not to do that. I'll look at the headers tonight. I have another PCM coming probably tomorrow with my tune and a corrected AFR. If that doesn't fix it I guess it's time to start taking things back off.
I am concerned about the pushrods. I have used Comp Cams lifters and now GMPP, and never had to get custom length pushrods, with Fel Pro and GMPP head gaskets as I have done this engine a few times. Do yo have pics of your heads with valve covers off to see the geometry and studs etc etc
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
I thought I did it correctly.
As for the push rods. Aren't the stock rods 7.2? That is what I have in there now but hardened Trick Flow's and they are damn close to the center of the stem. A whole lot better than the 7.1 that was suggested I use if not measuring. I don't think I have a photo that would be close enough to tell anything about the valve train.
As for the push rods. Aren't the stock rods 7.2? That is what I have in there now but hardened Trick Flow's and they are damn close to the center of the stem. A whole lot better than the 7.1 that was suggested I use if not measuring. I don't think I have a photo that would be close enough to tell anything about the valve train.
Thread Starter
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
Could these be to strong?
Could the lifters be collapsing? They have started to tick a little. Would a heaver oil help this if they are?
Got the new PCM yesterday with my tune in it and adjusted AFR. Seems a little better but still not right. It was recommended that I use Autolite 104's for plugs gapped at .030. I did that and the idle is awful but accelerates nicely it seems. I'm going to re gap them to .050 and see if that helps the idle any.
Got the new PCM yesterday with my tune in it and adjusted AFR. Seems a little better but still not right. It was recommended that I use Autolite 104's for plugs gapped at .030. I did that and the idle is awful but accelerates nicely it seems. I'm going to re gap them to .050 and see if that helps the idle any.
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Could the lifters be collapsing? They have started to tick a little. Would a heaver oil help this if they are?
Got the new PCM yesterday with my tune in it and adjusted AFR. Seems a little better but still not right. It was recommended that I use Autolite 104's for plugs gapped at .030. I did that and the idle is awful but accelerates nicely it seems. I'm going to re gap them to .050 and see if that helps the idle any.
Got the new PCM yesterday with my tune in it and adjusted AFR. Seems a little better but still not right. It was recommended that I use Autolite 104's for plugs gapped at .030. I did that and the idle is awful but accelerates nicely it seems. I'm going to re gap them to .050 and see if that helps the idle any.
That is quite a bit of seat pressure. What is your installed valve spring height?
If it is less than 1.800, you could have 170 pounds on the seat.
If you did not measure the distance from the top of the valve sping seat to the bottom of the retainer (installed height) you need to pull one apart and do so. Also, find someone with a spring tester, and verify the spring pressure is what it is supposed to be both at the installed height, and open height.
I have a hunch you are beating your valvetrain to death with those springs. Verifying open and closed pressures will confirm or deny that.