Stuck halfway through cam swap, help
Stuck halfway through cam swap, help Ok, So I am replacing cam, oil pump, chain, lifters (ls7), ECT. I have the timing cover off, old cam out, and new cam (ms4) already installed. I have the heads off, removed my old lifters, but I am now stuck on what to do.
I bought stock gaskets, and using stock rockers, and heads.
I bought new springs and 7.375" pushrods.
Of course I could put all my parts together, bolt everything up and just hope for the best but I would like to properly measure pushrod length and piston to valve clearance before I go any further. Neither of which am I too familiar with.
As of right now, lifters are NOT installed.
Cam is inside car, and I put the plate with the 4 bolts back together, nothing else has been touched.
Anyone know which direction I should move to next, and anyone know of good write ups on how to check pushrod length and piston to valve clearance? Do I need to find proper pushrod length first? ECT. any help would be great.
I bought stock gaskets, and using stock rockers, and heads.
I bought new springs and 7.375" pushrods.
Of course I could put all my parts together, bolt everything up and just hope for the best but I would like to properly measure pushrod length and piston to valve clearance before I go any further. Neither of which am I too familiar with.
As of right now, lifters are NOT installed.
Cam is inside car, and I put the plate with the 4 bolts back together, nothing else has been touched.
Anyone know which direction I should move to next, and anyone know of good write ups on how to check pushrod length and piston to valve clearance? Do I need to find proper pushrod length first? ECT. any help would be great.
TECH Senior Member
Joined: Mar 2004
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From: BFE
Joined: Aug 2007
Posts: 24,241
Likes: 89
From: Turnin' Wrenches Infractions: 005
I would "lightly" install the heads with the old gaskets (already compressed), and get a pushrod checking tool with a checker spring to keep the lifters from collapsing. Get your PTV/PR measurements and if all is good do a final assembly and double check a final time before you button everything up for good.
Its been quite some time, but as far as the pushrod length goes, the checker I purchased was pretty self explanatory.
As for the PTV clearance, that was a long process to learn on my own, but figured it out after purchasing another new cam (smaller) because I kept getting contact with the MS4 due to improper checking (torquing the rocker bolt instead of leaving hand tight).
But I used checker springs which I bought from jegs as well as welded lifters for peace of mind when I checked and clearances were more than enough once I finally figured out what I was doing.
Car ended up spinning a rod bearing on the dyno during tuning but everything went good on a brand new short block from Thompson motorsports.
As for the PTV clearance, that was a long process to learn on my own, but figured it out after purchasing another new cam (smaller) because I kept getting contact with the MS4 due to improper checking (torquing the rocker bolt instead of leaving hand tight).
But I used checker springs which I bought from jegs as well as welded lifters for peace of mind when I checked and clearances were more than enough once I finally figured out what I was doing.
Car ended up spinning a rod bearing on the dyno during tuning but everything went good on a brand new short block from Thompson motorsports.
