are they a direct fit? i have 7/16th studs and pro magnum rockers and am putting in the cc xfi 280 cam. dont want finiky lifters.

does anyone know the part # for them , or the caddy racing lifters?

 

They'll fit . GM part # 12499225
Try Summit.

 

A search should find you plenty of discussion and part numbers, too.

 

I was too lazy to run out to my garage amd look at the numbers. I should have, it would have been faster. I searched and after 15 minutes of reading thru useless junk, I found it. It would be nice to have a sticky for some common part numbers, i.e. lifters, head gaskets, etc. The search tool can be your friend but at times , it's a PITA.

 

but, remember - the cups are not the same, so you will atleast need to check your valvetrain geometry.. might need difrerent pushrods

 

From what I have seen, the LS7 cups are .005" - .010" deeper in the lifter body. In a perfect world you would need .010" or so longer pushrods. In reality, no need to change push rods.

 

unless u never checked it before and your already at the edge of acceptable. its worth a check at very least.

 

It would be nice if one of the people that visit the forum and who have used these lifters would tell us if they had to use 7.25" or 7.3" pushrods instead of the stock 7.2". ISTR it was said that the pushrod cups in the lifters were a down a little deeper than the stock LT1 cups.
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You guys are just too quick at the keyboard!!! I guess I mis-remembered and thought the difference was ~.1" instead of .01"!!!

 

I use them, but my block is decked, and my heads are not stock, and I am using a .026" gasket.. so with all those variables.. it wouldnt do you any good to know that im using 7.050".. but there it is anyway.

 

this is a fresh build. eagle 3.75" 4340 crank, billit 4 bolt cap w studs, 6" h-beams , srp forged flat tops .060 over, 0 decked, .039 gaskets, trick flow 195 heads that have been worked on, xfi 280 cam, full roller rockers, 7/16th studs, ep chain set, lt4 intake , edelbrock t.b., steped headers, 42psi injectors. nitrous single fogger .

plan on makeing sure rocker geometry is right.(that is part of building a motor) the LS7 lifters will be here wendsday(damn holidays), so i will post up what i end up with.

rest of the car is a 94 camaro z-28 . vented opti, msd, catless, 3" cat back, built trans, moser 12 bolt 3.73 , bmr tq arm , frame conectors, lower arms. plus i have a good friend that has a superflow chassie dyno. and all the tunning software.

 

Just to let you all know, I ran into a little problem but it was easily resolved. The individual part # is 17122490. In my "kit", I received 2 boxes with a quantity of 8 lifters, also with this same number on the box. The part number #12499225 is for the qty of 16. Combine 2 boxes of #17122490 = part #12499225. Just wanted to clarify so no one has any doubts.

 

Bought them at a dealership. They fit with no problem. I used 7.2 chromolly (spelling) pushrods when my head and cam kit was done.

 

well i ended up needing a 7.150 pushrod to get the tip to ride on the valve right.

woo hoo its gonna run tomarro. just need to bleed the brakes and put the battery in.

 

I used the LS7 cause they said direct replacement, and they were cheaper. They were not direct replacement. Yeah they fit in the bores, but they are a lot shallower then OEM LT1 lifters.

I used them in conjunction with the .026" Victor Rienz head gaskets and some GMPP 1.6 rrs. My block is not decked, nor were my heads milled. However when I put it all together with 7.2 pushrods it ran like it had a massive cam in it. Not in the good way either. Granted having 6 month old gas in it could have played a part, but not entirely

Knowing something was wrong, I opened it back up and checked the valvetrain geometry. It was all messed up. The rocker tips were way to far over on the valve. I measured for the correct pushrod size, and turns out I needed a 6.881 pushrod for the rocker tip to stay centered on the valve.

I dunno bout you all, but that is a pretty big jump from 7.2 pushrods to me! I'm actually kinda baffled. I haven't tested the new pushrods yet (putting them in this weekend), but I did check one, and the geometry looks right now. Because its such a huge jump in size it has me questioning...we will see this weekend.

 

Something sounds way out of whack for you to need such a different size. I hope you measured at several valves. Seems odd, given that I have read many threads that said they merely swapped them out and they were fine.