QCKZ28

ok here is a complete (at least that is all i ordered) list of part numbers and descriptions for everything needed to upgrade to 1.6 RR self aligning rockers on stock cam/heads:
1. LT4 valve springs p/n 12495494 (handles up to 0.525 lift)
2. LT4 valve spring keys p/n 12495503
3. LT4 valve spring cap kit (retainers) p/n 12495492
4. K-line 11/32 valve stem seals
5. Proform aluminum 1.6RR self aligning for SBC with centerbolt valves covers 3/8" jegs p/n 778-66915C
6. valve spring compressor p/n KD3271 (screw type) one of many types available.
7. air fitting to keep valves up
8. LT4 valve spring shims (sold individually, you need 16) p/n 10212809

if you use non self aligning RR you will need a set of 8 guideplates. i wrote this post because i see alot of people like my self has been asking questions about upgrading to 1.6RR on stock cam/heads. i found that most of the info was spread out and it took me a lot of time to sort through it all. I HOPE THIS SAVES SOMEONE SOME TIME
and from what i have read it is very much worth the $300-400, people have dynoed 20-25rwhp from this mod alone! i will let everyone know if i can tell a difference when i put them on...oh and if i left something off someone please correct me.

DropZ

This list helped me out, thanks. I already had 1.6 rockers and needed to know what other parts would be necessary, the only thing I changed is I ordered GM valve seals:

(8) 1994-1997 intake valve seal - p/n 10212810
(8) 1994-1997 exhaust valve seal - p/n 12564852

I am also going to be using "Tim's tool" valvespring compressor from LS1tech.com instead of the standard rental/OTC screw-type valvespring compressor

I will update this post with prices once Dal e-mails me and lets me know what everything cost. I am excited, I will have basically a whole new valvetrain because I also got new lifters and pushrods.

BUBBA

You shouldn't need to use the air pressure to hold the valves up if you have the pistons TDC. At least that's the word---valves shouldn't drop into the cyls with pistons at tdc. Saves the hassle. JMHO

Bow94z

wow great thread man....

Just in time, cause i was gonna make this move on ordering things within the next month or so..

how many miles on bottom end?

godspeed1976

Just saw this, perfect timing! Thanks man!

DropZ

I am also upgrading to 3/8" ARP rocker studs, since they're quite cheap. I'll get the part number and price listed tomorrow, in fact I'm going to make my own full list since I'm also using different rockers, Comp Cams Pro Mags.

Paulster2

What happens if you forget to rotate to TDC? Or if you misalign and aren't at TDC? While I believe you are right in your assumption, take the extra time to pressurize the cylinders. It's worth the added insurance of not having to tear the engine apart because you dropped a valve. Just a thought.

godspeed1976

Forgive me for sounding stupid but I thought the valves used the same diameter stem on both intake and exhuast is that correct? or do I need to order 8 of each like you listed?

DropZ

I am not sure, I got those part numbers from Shoebox's site, www.shbox.com. I assume since the original poster used only one type of valve seal, the "K-line 11/32 valve stem seals" that they are indeed the same. I just ordered them separately because that's how Shoebox's site has them listed.

BUBBA

What happens if you forget to rotate to TDC? Or if you misalign and aren't at TDC? While I believe you are right in your assumption, take the extra time to pressurize the cylinders. It's worth the added insurance of not having to tear the engine apart because you dropped a valve. Just a thought.

If you can't remember to rotate to TDC on 8 cyls, then maybe you should let someone else do it. I would think that having to remove all your plugs, screw in a fitting to attach a compressor to hold the valves up, replacing the plugs, etc. is overkill. You should probably bring the the Pistons to TDC when you do an initial adjustment anyway.

BTW, some use the cord method, which involves stuffing cord in each cyl to keep the valves from falling. Just saying that the pressurizing the cyls to change the springs is not the easiest thing to do on an LT1 F-Bod.

It's your mouth, you can haul coal in it if you wanna. Just kidding.

DropZ

Well, here is my final parts list. I don't have prices for all of it yet but will update this post with prices when I get them.

1. LT4 valve springs p/n 12495494 (handles up to 0.525 lift)
2. LT4 valve spring keys p/n 12495503
3. LT4 valve spring cap kit (retainers) p/n 12495492
4. LT4 valve spring shims (sold individually, you need 16) p/n 10212809
5. Comp Cams Pro Magnum 1.6RR 3/8 stud self-aligning, p/n CAM1318-16, $270 + shipping from Combination Motorsports
6. Tim's Tool Valvespring Compressor, e-mail Ramair69gto@sbcglobal.net to order, $30 shipped
7. ARP 3/8" Rocker Arm Studs, 1.75" length, p/n ARP-134-7101, $40 shipped from Summit
8. GM Hydraulic Roller Lifters for 93-95 LT1 F-body, p/n 5234890, $20 each (need 16)
9. Chrome Moly pushrods, unknown brand, stock length 7.200"

Some notes: I got the pushrods, rockers, and lifters used off various F-body boards so I paid far less than the retail prices quoted above. You may want to use p/n 17120735 for lifters as they are a newer design for 96-97 F-body, or go with Comp or an aftermarket brand as the GM stock lifters aren't cheap. All the LT4 springs/locks/retainers/shims were purchased from Dal, I will update their prices when I get them. I decided to go with Tim's Tool valvespring compressor because I have heard the rear-most springs are a PITA and Tim's Tool supposedly makes it pretty easy. ARP Rocker Arm Studs aren't a requirement but they are cheap insurance on a 118K mile motor like mine, the same could be said for the lifters and pushrods.

526 SS 96

Use the compressed air while changing springs. Think of this... if the valves are not on their seats, just how far are you going to have to compress the spring before you can fit the locks on the valve stem? Hopefully it's before the bind point on the spring, and before the retainers hit the valve seal. Make life easy, do it the right way.

1SlowFormula

Umm this doesn't make much sense. The valve will always be on it's seat since the rockers are removed before the springs, causing the spring to push the valves into their seats.

As for the choice between using AIR and not is actually up to the individual and how that are doing it as well as how they plan on setting lash. Some don't have access to an air compressor and if you are doing them one at a time and setting lash as you go the TDC method would be best, if you have access to AIR then go that route...

However, There is a thrid choice too, I didn't use either method... I just pulled the springs and most of the time the valves didn't move and those that did drop some always stopped before getting into the seal and I could use a magnet on them. Think of it this way, the stock valve is ~ 4.965", are between 1.5-2" wide at the cyl end, and are on a 23* angle to the cyl surface. The stock stroke is 3.48 meaning that there is no way the valve will drop into the cyl. even at BDC. Also, most find their stock install height is 1.795" to 1.889" and some have seen as low as 1.631" meaning you normally have about 1.5" or so before the valve goes into the valve seal, so in other words if one drops it's not going far and again when I did mine the ones that dropped never made it far enough a magnet couldn't retrieve it...



BTW, did all you guys that responded with statements like "just in time" and "perfect timing" realize this thread is 3 yrs old??? Searching is always a great tool...

godspeed1976

Yeah I saw that it was old but I was refereing to the revival of it being just in time so that I didnt have to search for it.

That is really good info on dropping valves, and is what I always thought, but was to scared to experiment for myself. Glad you did the math, you just made this install, much easier.

zx1216

Just a FYI the valve drops maybe a half inch before it hits the piston at TDC, if you install new valve seals at the same time like i did they will hold the valve on its seat while you install the springs. I was going to use the air method and said screw it since geting an air hose in there looked like a major PITA. Everyone has their own way of doing things, some find it easier to do one over another, i don't see that there is one "right" way though.