Lifter mod FYI

[geldartb]

i did it more to re-torque the cam gear bolt. i already had the top end off and its not much more to do that. i honestly hope it shuts it up a good deal.

this is the last time the side cover will be off. while i was at it i went ahead and got the metal fel-pro gaskets for the lim so that will be set it and forget it too, well until i go the diamond piston route. too bad i couldnt drop the pistons out the bottom.

[3400-95-Modified]

Well here are my pics of the LS1-LS6 lifters I just got off of e-bay. New, not used.

I'll snap some side by side pics with what POS's come out of my car... I'm expecting something to be wrong with some of them... not sure what to expect quite yet though... I've seen the lower spring destroy the check valve completely and then disintegrate before in the race motor, but I don't think mine is that bad yet.

Oh yeah has anyone determined if we can use the internals of the high performance lifters for the LS6's and such to support high rev's?? just curious since we are kinda using LS1-LS6 performance type springs... so yeah the LS6 lifters are definitely an upgrade over our stock ones, but still not necessarily meant for the performance type spring for the LS1/LS6. Oh and I know we use the internals of this lifter, but I've never compared them side by side yet... Are they physically longer? or bigger diameter and that's why we cant use the whole thing?

[34blazer]

see if they will fit then check if the oiling oils to see if they protude from the lifter bores on the heel and at peak lift. iirc the genIV smallblocks still used an .842 lifter bore


*edit* sh*t, it says it right on the box. gen III and IV lol

[3400-95-Modified]

I sent Dave a PM asking if he used the whole check valve assy and the spring, and then the rest of the 3400 internals... since I can't get the check valve off the bottom of that part to get the spring separate from it... its pressed in there good. I do have 4 that I can "break" to see how hard it is to separate if I want, since I did get a V8 kit.

[3400-95-Modified]

Well, compression check shows 175 PSI on every cylinder, engine ice cold, after it has been sitting for 1 week or so... so that's a good sign of solid ring seal, and no head down issues with my motor... So I'll be pulling the top end sometime possibly tomorrow or next week and making sure I get plenty of pics on what I do with my lifters to add to this thread.

[RedBird]

we used the main plunger spring and the check ball spring when doing the lifter mod. everything else from the 3x00 lifter was retained. that cap does come off so you can get to the check ball spring, but yeah they're pressed in there a bit. just pry with a pick and it should pop off

[geldartb]

i used a flathead jewlers screw driver to pop the thing off so i could get the check ball spring out.

[3400-95-Modified]

Yup, grew some balls and grabbed with a pair of needle nose and it came apart. I just hope my stock 3400 ones aren't destroyed if so I gottta pull apart my 3100 at home for some parts.

[3400-95-Modified]

Here are pics of Stock vs LS1-LS6 lifter parts. Stock on right.





I dont have any LT1's to compare it to.

[Keoki1978]

Just wondering if its worth switching parts from one lifter to the other?? I'd think it be better to swap them for lifters specific to LS series engines. If RPM is an issue, I've seen and herd of some comp cams hydralic rollers hitting 7200.

[geldartb]

you cant use the LS or LT series lifters there a quite a bit taller than the 3x00 ones.

[1988GTU]

Could the LS or LT lifters be used with much shorter pushrods or does the oil hole not line up properly?

[bszopi]

If height is an issue with the LSx lifters, then it would not only be an issue of pushrods, but also of the lifter retainer. So even if shorter pushrods were used, you'd have to figure out a way to make the retainer work, which could then introduce possible clearance issues with the lower manifold.

[3400-95-Modified]

as much of a pain in the ass it is to swap out the springs, its really the only option we have to beaf up our lifters.

I just finished all 12 of mine... No physical damage in any one of the lifters, I wish there was something that pointed to a sign of weakness there but there wasn't... I'm just hoping that this is my problem and it fixes it.

Time to re-assemble.

[Keoki1978]

I havent had them in front of me to compare. How much longer are they??