|
|
|
Re: Valvetrain issues
[Re: clovis]
#2901312
03/21/21 11:49 AM
03/21/21 11:49 AM
|
Joined: Jan 2003
Posts: 14,498
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,498
So. Burlington, Vt.
|
Have you measured the lift at the valve, with zero lash to see what the effective rocker ratio is now?
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
Re: Valvetrain issues
[Re: clovis]
#2901315
03/21/21 11:54 AM
03/21/21 11:54 AM
|
Joined: Aug 2011
Posts: 2,860
Pattison Texas
CSK
master
|
master
Joined: Aug 2011
Posts: 2,860
Pattison Texas
|
Springs are all installed, most came in about 1.81-1.83 and that puts them between 150-155 on the seat.
Went ahead and milled the hold downs and got everything shimmed and spaced. I installed the new shaft spacers and mocked up a pair of rockers to measure the scrub and see how everything lined up. With the shaft spacer (+.150) the rocker tip is fairly centered on the valve, the adjusters are about 1.5 threads out and looks like it will allow oil to reach inside the pushrod cup. The scrub, the best I can measure is coming in between .035-.037, so a significant improvement over my previous .135 and not too far off the theoretical ideal of .031.
The only thing that seems strange is the pattern on the exhaust valve is not all the way across. I measured several times and each time it would be the same partial pattern. I am only rolling it over 720* by hand to get the pattern and I am running about .025 rocker clearance. I checked a few time to ensure the rocker was centered over the valve, so I am unsure what the cause is.
Everything is better with pictures
Spin the valve 180 deg & see if it changes, the valve tip might be faced at an angle,
1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5
|
|
|
Re: Valvetrain issues
[Re: CSK]
#2901448
03/21/21 09:43 PM
03/21/21 09:43 PM
|
Joined: Mar 2008
Posts: 553
Kentucky
clovis
OP
mopar
|
OP
mopar
Joined: Mar 2008
Posts: 553
Kentucky
|
CSK, good call on turning the valve that seemed to do the trick. I did try another rocker before turning the valve but it didn’t change the one sided valve mark.
Fast, I got a chance this afternoon to measure the lift. I got .583 with no lash, so that would put the ratio at 1.606.
At this point, I am going to put the rockers back on and move to the next project - installing an AFR gauge.
I appreciate everyone’s help.
'75 Plymouth Duster
Phase I 451 906/590/2-660 10.75/126
Phase II 451 Stage VI/590/1050 9.82/135
Phase III 383 906/Victor-Pump gas 11.30/119
"For by grace you have been saved through faith. And this is not your own doing; it is the gift of God,"
|
|
|
Re: Valvetrain issues
[Re: clovis]
#2901537
03/22/21 10:35 AM
03/22/21 10:35 AM
|
Joined: Jan 2003
Posts: 14,498
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,498
So. Burlington, Vt.
|
I think you’ll find it revs much easier/higher than it did before.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
|
|
|
|
