I did a search on this and didn't have any luck. I am going to be putting this cam in a 94 T/A here in a month or so. I have read in the past about dowl pin problems, timing chain problems and so on. The plan is to go with a CSI waterpump and the timing chain set that doesn't cost 500 bucks. Which set is that? Also do I need to plug anything in the timing cover since the waterpump wont be driven off the cam? Is there anything else I should know? I appreicate it.
Jason

 

I used the LT4 extreme duty timing chain set....cost $219. As far as the shaft hole in the cover ...just knock the seal out and put a block plug with some RTV on it in there....I took the cover with me to parts store to find the right size.

 

Without converting to a vented opti you need either the LT4 extreme duty or a stock replacement timing set. I don't know of any other available. If you convert to the vented opti style drive you can use a std sbc timing chain. Personally, i just replaced the chain and reused the timing set itself. I felt i had relatively low milage and was doign this on a budget

If you leave the waterpump drive in place you will not have to do anything to the timing cover. If you want to remove it you will need some type of washer and nut setup to block the hole on the waterpump. You can also put a freeze plug in the opening in the block although i don't think everyone does that. I just left the drive in place so i didn't have to mess with closing up the timing cover and it wasn't interfereing with the CSI.

On a 94 the dowel pin doesn't really do anything and its length isn't critical as long as it's not slapping the inside of the timing cover. You could scrap that mother altogether as long as you have the 3 bolts to the timing gear oriented right. I just hacked mine down about 1.4 inch till it would clear everyhting and left it in for the small amount of balance it would provide.

-brent

 

Since you have a 94, you are stuck with a stock timing chain. On the 93/94 models, the distributor has a splined shaft that fits into the gear of the timing chain. That's the part that gets you. Neither the LT4 / LT4 Extreme Duty nor any of the aftermarket chains (that I know of) fits with the unvented Opti and its drive setup. If you want to go with a Cloyes True dual roller setup, you would have to change to a 95 timing cover. This will allow you to switch to the more reliable vented Opti. The 305 cam will come with the longer dowel pin needed for the drive setup on the vented Opti.

The Cloyes timing chain is significantly cheaper ($80) and stronger than stock. By changing the timing cover, you get to use a cheaper Opti, too.

BRAD

 

I'm bored tonight (whats new) so i'll make the list of other things to know a big one:

Use shoebox's guide

clean clean clean your motor first.

Put a trashbag over your ac condenser when you tilt it up because crap will fall out of it all over your cam if you touch it while putting the new guy in.

On a 94 you don't need a harmonic balancer puller, just a 3 jaw gear puller. Newer LT1s have a slightly different hub/pulley assembly. The puller i bought came with two sets of metric bolts which were to small anyways and i had no trouble with a 3 jaw puller i already had and a longer bolt to reinstall the hub. Lubrication on hub reinstallation was debated and the consensus against me so i guess don't lubricate it

My crank had a hash mark on the front which matched the balancing drill hole on the side of the hub.

Remember once you have the cam out the bottom end goes through an acceptable TDC position every 360deg rotation instead of every 720 since you don't have valve timing established and the fireing order will be OK since the opti is keyed. In other words, once the cam is out the bottom end doesn't care if it was on the intake/ power or compression/exhaust strokes. This is actually probably confusing you more right now, but other people have wasted a lot of time fiddling around with this double checking and making sure they were right and not accomplishing anything.

The oilpan is a PITA, you will need some extensions and swival for that along with removing the oil cooler if you have one. Don't rip that seal.

Check your rockers to make sure they are all SA or nonSA and you didnt' get a mismatched set like me, haha.

After tightening the set screw on your polylock give the whole thing another lil turn to lock it.

Looks like your not a novice by the motor in your sig, so maybe you knew this stuff but it will help someone else.

Most importantly, use the search button because you can find anything and everything on this site

-brent

 

Interesting, i thought the LT4 ED would work...........i was just too cheap to buy it,