replacing P/C's, possibly Hydraulics?

[guards73/2.0]

I just visited the Formula Vee shop where the guy pulled my motor to tell me just where I botched my topend rebuild ( could have used that tape). Here's the deal
1) machine shop didnt loctite the helicoils ( all 4 leaking)
2) improper deck height measurement led to "cocking" of
heads on jugs, causing blowby and oil leaks in two cylinders.
3) I may have hydraulic lifters ( surprise! explains valve adjustment probs) installed by PO ( he's
going to bench-test to verify, but they look like hydraulics, they have that center band machined in their sides that look like hydraulics I've seen).
4) might have needed Pistons and cylinders ( if needed GEX
has Mahle 2.0 96mm st for 350.00, Pelican is 100.00 higher)

Questions:
Are hydraulics a good thing or is the performance tradeoff too great?
What should I say to the machine shop ( car's been sitting for
20 mo. since work was done, car ran for 10miles ( badly)?
Are the HiPo europistons worth the extra dough if I need them?

[Will98D]

oh boy... can I go first? Hopefully you will still be able to find in the archives a post with about 50 replies that had lots of flames, remarks about engineers, mechanics and auto companies, testing, and various debates about who knows what. However, at the end of the day, most people with Type-IV performance experience said use mechanical lifters only, that hydraulics in a T-IV lead to a diminished engine life.

{Edited} Here, I went back and found it... and it was only 48 replies.

Hydraulic Vs. Solid Lifters?

[guards73/2.0]

My car came with the WebCam and hydro setup. I wasnt aware or this and adjusted my valves and burned a valve seat out and
dropped it (ouch). Now I KNOW I have hydraulic lifters. I'm replacing my pistons and barrels, and since I don't need a compleat O/H yet and you're no supposed to change lifters w/o
changing the cam, I'm kinda stuck with the hydraulic lifters for this go round, anyway.

[Jake Raby]

It has been almost 400 engines since the last hyrdo equipped baby left my shop....I feel so strongly about them that I refuse work for those who require them....

Keep it slid, keep it alive.....and keep adjusting the valves.

[roadtrp204]

Just a note that the Cofap P/C kit you refered to is a dished set while the Mahle is a flat top kit. With the following set variables, this is the difference in compression.

bore 94mm
stroke 71mm
combustion chamber 60cc
deck height 0.035 in
no head gasket
Cofap 15cc dish vs Mahle euro 0cc vs OE us spec 7cc

Cofap 7.1:1
Mahle 8.4:1
OE US 7.7:1

I replaced mine when I dropped a valve seat about ten years ago with a set of Cofaps. Though it still seemed to have decent power it was a bear to tune and for the most part it still ran rich. These are replacement bus pistons.

[guards73/2.0]

I've since swithched to Ciba p/c's from aircooled.net. They are the
euro type with spuncast ( but not forged) and don't have the same inconsitent quality reputation and are even cheaper.