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Been building this car for 10 years, now finally ready to tune and drive it. Than this happens before hitting the road. Never did head removal, springs before but being retired I have time to get it right.
Any idea what it is?
Slightest touch of the gas peddle the knock gets louder. Other problem is that I'm 1,500 miles away from my tuner and he doesn't remember what model springs he installed 10 years ago. So I have to figure out how to correctly measure them.
That dosen't sound like a rod knocking it's sounds valvetrain related to me. I'd probably drain the oil and inspect the oil filter first and from there I'd remove the valve covers and check the pushrods. What all has been done to the engine?
That dosen't sound like a rod knocking it's sounds valvetrain related to me. I'd probably drain the oil and inspect the oil filter first and from there I'd remove the valve covers and check the pushrods. Push rods are straight and like new. Rocker are perfect, At glance the double springs look good but that doesn't mean the small on the inside is not broken. Next I'll do a compression test before removing heads.
What all has been done to the engine?
This is installed in the 68 catalina:
C5R block
Callies dragon slayer 4.0" crank
Comp star rods (made by Callies)
Weseco pistons -8 cc
ETP 225cc heads , ported to 232cc by WCCH 2.12 intake 1,94 exhaust valves, .700" lift valve springs
Cam 255/257 .624/.624 lift on 111 +4
Super Victor intake
105mm TB with custom elbow
Stock rockers
LS7 lifters
ported oil pump
dual roller timing chain
That dosen't sound like a rod knocking it's sounds valvetrain related to me. I'd probably drain the oil and inspect the oil filter first and from there I'd remove the valve covers and check the pushrods. What all has been done to the engine?
Originally Posted by LS1Formulation
Did you check all those rockers thoroughly? You may have lost some needle bearings which would account for the noise.
If you're lucky you'd see needle bearings on the top of the head under the cover before they make it in the pan. Many people will ditch those caged needle bearings and install a bushing style trunnion and CHE makes the best one if you ever decide to upgrade. Those LS lifters are very forgiving and don't quote me on this but they operate in the .070 preload range. Many people use the OEM style lifters and those plastic trays that hold them but I'll always use link bar style lifters for a performance engine. BTW I noticed the PR length was 8.15 on your pushrods did you verify PR length?
I installed tinuion lifter kit from CHE precisions, changed the plugs, cleaned the injectors. It idles smooth but knock is still there when giving it a litter gas. I did notice the AFR gauge increases passed 15 while steping on the pedal.
I double check the AFR settings, I lowered the idle advance down by 3 degrees and the knock was still there. so I put the back to where they were set. I'm trying not to pull the heads and then find out it was a tuning issue. Yes I know how else do we learn. Being over 60 it's not as easy as it used to be. I'm new to this computer tuning stuff. Give me a carburetor any day. History: This motor is 15 years old, I've had it for 13 years and never ran down the street, only started over from time to time to keep everything working. Now the car is running, I put 76 miles on this motor that knocks only while accelerating. But don't want to kill it. My tuner is 1500 miles away, thanks to me retiring in FL. Any good tuner is 3 hours on the other side of town. I'm leaning on changing the LS7 lifters.
Many possible causes for knocking. Headers had a small leak, possible sucking air back into the chamber. All the carbon on the pistons and heads may do it also.
New rockers should be here tomorrow. I have some major cleaning to do.
Do I need to replace that style of head bolts?
Those look like ARP studs to me which are reusable. Just make sure they're in hand tight and use ARP fastener lube on the washers and nuts to reach proper torque.
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LS3 motor knocks getting louder 
Than this happens before hitting the road. 
Never did head removal, springs before but being retired I have time to get it right.
