ThunderboltZ28

Are the GM LS7 lifters direct replacement for the stock lifters? Or would I have to change anything?

kinglt-1

iTrader: (26)

yes they are a direct replacement!

Elliott's94Z

iTrader: (12)

What he said...I'm running them on my current set up.

ThunderboltZ28

Do I have to prime these lifters? I've heard from some that they come preprimed and priming them is just useless. Any truth to that?

robsquikz28

iTrader: (246)

yes sir x3

MDR

iTrader: (1)

I just installed the LS7 lifters in my car with the new cam and rockers. One thing to note is that the cup is .120 shallower on the LS7 lifters than the stock LT1 lifters. This is the first time I have changed lifters in my car, but I do know that my pushrods ended up being .150 shorter (7.050") than stock with LS7 lifters, CC503, and ProMag rockers. Comp recommends a 7.200" with the STOCK lifters, CC503, and ProMags. Maybe someone else has a definitive on plunger travel between the two and how preload affects the difference in cup height?

JB_97ws6TA

iTrader: (6)

I am also curious how these things stack up against aftermarket lifterrs such as Lunati or Comp??

Big bird55

iTrader: (1)

so do you have to get a longer pushrod. if so how big im about to have to put lifters in my car also would they hold up to the comp cams 306 cam?

MDR

iTrader: (1)

Well I know that my good friend is running the LS7 lifters in his extreme LS6 with over .650 lift so I think they will hold up to the CC306 just fine. To make sure you are using the correct length pushrods get a checking tool from Comp ($12) and perform a wipe smear pattern test on the valve stem. I modified an LS1 lifter to make it solid so when turning over the motor I didn't have to worry about the hydraulic lifter collapsing. The LS1 lifter cup is .o6o deeper than the LS7 lifter. I'm running .060 of preload so the final reading of pushrod checker was perfect for my application. When I said shallower in the previous post I mean that the cup sits higher in the lifter body. Hope this helps.

ss.slp.ls1

iTrader: (36)

Yes, they will drop right in. You should clean the lifters with alcohol and soak them in oil.

You should always measure for proper pushrod length, some need to use slightly longer pushrods.

ThunderboltZ28

I have a CC305 cam, Comp Cam 1.6 Pro Magnum roller rockers, and Beehive springs. Do you think my stock pushrods will work with the LS7 lifters?

ss.slp.ls1

iTrader: (36)

Stock length or the actual stock pr's?
No, the stock pr's will not work. You will need hardened pr's. I recommend getting a set of Trickflow chromemoly pr's.
As for length, you will probably be fine with stock length (7.2"), but it is always recommended to measure for proper pushrod length to be absolutely sure.

EDIT: Missed the LS7 lifters...stock length probably won't work for you, you need to pick up an adj. pushrod and either a test spring or a solid lifter and observe the wipe pattern using the sharpie method to find the proper pushrod length you require.

the_merv

iTrader: (88)

I have always seen the LS7 Lifter difference measured in at .050" difference..

ThunderboltZ28

Once I find out which length pushrods I need where would I get them?

ss.slp.ls1

iTrader: (36)

Summit.
Trickflow chromemoly pushrods part # 21407xxx. $86.95

xxx = your pushrod length (example: 7.200" pushrod means part #: 21407200).

OddballLt1

iTrader: (1)

Would Stock length PR's work on a stock cam with 1.6 rockers and LS7 lifters? Im about to set my valvelash, Should I get a PR tool to be safe?

ss.slp.ls1

iTrader: (36)

I would.

H'ville TA

Does anyone know the part number and price for the GM LS7 lifters?

monster81

gm# 12499225

moehorsepower

iTrader: (3)

I believe I paid around $120.00 from Scoggin Dickey Chevy...