engine has a miss

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Dec 27, 2008 | 05:51 PM

#21

dougbfresh

Le Mans Master

Joined: Nov 2005

Posts: 6,993

Likes: 25

If you have the intake and valley cover off, why can't you get to the lifters?????????? Your question is weirdly worded-not sure what you asking exactly.

Dec 27, 2008 | 06:16 PM

#22

jaybar

Thread Starter

Racer

Joined: Jun 2007

Posts: 468

Likes: 15

From: Jupiter FL

Quote:

Originally Posted by dougbfresh

If you have the intake and valley cover off, why can't you get to the lifters?????????? Your question is weirdly worded-not sure what you asking exactly.

I am asking a number of things.
1. Yellow springs worth installing over after market.
2. When doing a leak down test how much time do I allow for each cylinder to get a reading or is it instantaneous?
3. I looked it up in the shop manual and I see that the lifters in their guides are installed in a slot in the block which is covered by the head. So I am assuming I will not be able to see the cam and lifters through the "top". I would love to be wrong on that one.

Dec 27, 2008 | 06:51 PM

#23

dougbfresh

Le Mans Master

Joined: Nov 2005

Posts: 6,993

Likes: 25

If your not changing cam/heads, stock springs are fine, leakdown is more about differences between cylinders (unless you get fast leakdown in all cylinders), your really checking leaks past the rings and valves. Watching and listening are important, leaks thoug the valves will make noise in the intake/exhaust. Leaks past rings will make noise in the crankcase. Compression and leakdown tests together give you a better picture of engine health.

Your correct on the lifters, the head has to come off I believe.

Last edited by dougbfresh; Dec 27, 2008 at 06:55 PM.

Dec 29, 2008 | 09:28 PM

#24

jaybar

Thread Starter

Racer

Joined: Jun 2007

Posts: 468

Likes: 15

From: Jupiter FL

Well, I did not know if you could see the lifters and cam with the valley cover removed. I searched several sites and finally came up with a picture of the lifter galley, or valley as it called on an LSx. It seems most of the cam and lifters can not be seen. It looks like maybe the #1, #7,and #8 can be partially seen, but I could not tell from the camera angle to what extent they could be evaluated. So I am going to save myself the trouble of removing the manifold and valley cover.

I borrowed a leak down tester (single gage) from a friend and will try it out over the coming 4 day weekend.

Last edited by jaybar; Dec 29, 2008 at 09:30 PM.

Dec 30, 2008 | 12:45 PM

#25

Fasthotrod

Melting Slicks

Joined: Mar 2004

Posts: 2,149

Likes: 6

From: NCCO Oklahoma

You have to pull the heads to replace the lifters.

We just did a set in my friend's 2005 C6 LS2. (Along with a few other mods... rockers, cam, supercharger, intercooler, etc...

)

http://forums.corvetteforum.com/1568125284-post891.html

http://forums.corvetteforum.com/1568200685-post122.html

http://forums.corvetteforum.com/1568238736-post249.html

If it was me and I was this far into the motor, I would replace the lifters, pushrods and springs.

LS1. LS2. LS6, LS7 lifters: $130
http://www.lingenfelter.com/store/12499225.html

Comp Cams LS1, LS2 stock length pushrods: $110
http://speed-eng.com/store/comp-chro...en-p-7601.html

LS6 valve springs: $53
http://www.lingenfelter.com/store/12499224.html

New spring retainers would be a good idea while you are at it...

At this point, you aren't too far off from a cam swap...

Good luck.

Mark

Feb 24, 2009 | 01:04 PM

#26

jaybar

Thread Starter

Racer

Joined: Jun 2007

Posts: 468

Likes: 15

From: Jupiter FL

The last two months have been busy. The following thread is my write up on the installation of the items suggested in this thread.

check out
http://forums.corvetteforum.com/c5-t...cker-arms.html

Thanks to all who have made suggestion and given advice.

Jay B

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