1fast432

First off sons 94 z had a leaking water pump,would not start after sitting for any length of time. Figured the optispark was going out. Fixed the water pump and car seemed to be running good and now looks like head gasket went leaking down from head onto block.While I have the topend off should I go ahead and replace the opti or could the hard starting be something else, tps ect..When you take off the harmonic balancer do you use a puller, seams way tight on the hub?Can I remove all the air pump hoses and plug the openings and run the pulley or do you take the pulley off and reroute the belt? Will it run that way at all before we can get a tune on it?Can you get the oil pan off without pulling motor out? Wanted to put in a high volume oil pump.Thinking of putting in a cam and headers on it, how much can you mill the heads with say a .56 lift cam and still have enough valve to piston clearance?He would love to make enough hp to eat his older brothers ls1 trans am. THANKS IN ADVANCE JOHN B!!!!!!!!!!!!

Schweet97Z

iTrader: (35)

Describe what the hard starting is like. Start with the simple, less costly items first when dianossing a problem. How many miles are on the car? If you do decide to change the opti, I would convert to a 95+ vented style. For the crank pulley you should use a puller, it is a press fit. Also there are three bolts that hold it in place. As far as the air pump goes there are no pulleys that run that. Pulling it off would be fine but you will need to get it tuned out as it will throw a check engine light. I would remove the EGR as well. The oil pan will come off but you will have to lift the engine just a hair. Mill the heads .010" and run Impala SS headgaskets and you will be right around 11.0:1 compression

busdude

what all does it take to convert to the 95 and later vented style ?

Schweet97Z

iTrader: (35)

Vented Opti
Timing Cover
Opti Harness
Vent Lines

Or you could run an MSD Cap and Rotor Kit which will convert your current opti.

1fast432

Hey schweet97z, thanks for the reply. Car would crank over fine but would not start. Used some starting fluid and finally got it started. Other day it sat for 48 hrs and wouldn't start then went out next day and started right up. Does the coolant leak penetrate the distributor and has to dry out before it will start again. Both times this happened the coolant was leaking.Is the vented style driven the same as the 94? THANKS JOHN B

Elliott's94Z

iTrader: (12)

If you are going to tear into it that deep I would rec changing the opti out for sure along with a new timing chain as well. If you do change out the cam and heads I would also replace the lifters/pushrods/valve springs and the other little goodies that go along with the swap just to insure everythings fresh and new.

lt1z28camaro

iTrader: (2)

If you plan to do heads and cam, If I were to do it again, I'd drop the motor out of the bottom. The tight space to work on the car got annoying. I've never dropped the motor out, it seems rather simple in comparison to leaving it in and trying to work around everything. Just my .02. And I also would replace the entire ignition system (opti, coil, plugs, plug wires) But I would stick with a gm vented opti, i've heard of too many msd's not workin out.. Good Luck!

Schweet97Z

iTrader: (35)

What do the plugs look like? Any corrosion on them? Coolant can leak into the opti itself and cause corrosion etc. Moisture will do the same. One of the reasons why GM designed the Vented style opti. Both vented and non vented are driven by the cam pin. Just remember there are three key components that make an engine run. Fuel, Spark, and Air. Make sure you have all them and try not to over analyze the situation. Start simple and work your way up to harder more involved taskes.

Harold

AChotrod

iTrader: (17)

My heads are milled .030 and Im running MR G 5716 .026 head gaskets. 11.4-1 compression

1fast432

Hey ACHOTROD, are you still running pump gas? Any spark knock? What duration cam do you run and what kind of piston to valve clearance did you have after milling?THANKS JOHN B

SS RRR

iTrader: (2)

It's possible the opti still has antifireeze trapped inside. If you want to be cheap, use a heat gun or let it sit in a climate controlled room for a few days.
That's just the way it is. Sometimes because of rust it can really make things tricky. The bible for LT1's can be found here (Courtesy of Shoebox):
www.shbox.com
That gives you one way to take the hub off. Here's a tool to reinstall the hub:
http://members.***.net/gmarengo/Misc/Misc.htm
On a OBDI car I'm thinking you may not have trouble codes thrown if you were to simply unplug the AIR pump. As stated it is not pulley driven. The one thing to keep in mind (if the catalytic converter is still on the exhaust) is the AIR pump provides more oxygen to heat up the converter quicker during cold startup.
On a stock stroke engine it has been reported it can be done by lifting the engine off its mounts and loosening the bolts on the k-member.
I'd advise against installing a high volume pump using the stock pan. There have been reports of cavitation and starving due to too much oil being pumped into the top end which ultimately has ruined a few engines. Stock volume with a GM "white" spring is all you need especially if your bearing clearances are at stock tolerance levels.
Dunno. I've always heard it's better to only take what's needed off and make up the difference elsewhere if high compression is desired. If you do a heads/cam swap with reputable parts the stock compression ratio will be plenty to beat (at least) a bolt-on LS1 and perhaps even cam only LS1's. You can achieve a smidge more of compression by using an impala gasket which I think have a .029 thickness. Very popular choice. Whether or not it's an improvement over stock CR is unknown.

lt170chevelle

iTrader: (2)

i wouldnt run a high volume pump either. its not worth sucking the pan dry at high rpms. and yeah with the non vented optis they are **** about any liquid getting on them. mine has fits if it sits for a few days. if you drive it for a bit it will clear up. and +2 on the dropping the motor out.. its very difficult trying to do anything in the cramped engine compartment.

the_merv

iTrader: (88)

These Engine like a good High-Pressure Pump.

SS RRR

iTrader: (2)

Care to explain in a little more detail?

the_merv

iTrader: (88)

Just the nature of it, these Engines like a good High-Pressure Pump, the LSX Engine like a good High-Volume Pump.

SS RRR

iTrader: (2)

There is no "nature of it.." If your bearing tolerances are stock then there is absolutely no need to run a high pressure pump. Not only that, but you then run into higher parasitic losses. High pressure is not always the answer to an oiling system. Here's some good reading material from an experienced engine builder:

http://www.camaroz28.com/forums/show...=oil+presssure