When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Originally Posted by Chimera96
well if the shop says it is external rear balanced...then your stock FW & clutch will work
You will know immediately when you start the car if there is a balance issue.
Did the shop use a donor FW or flexplate to balance it??
He didn't mention a donor FW but he was building a few more LT1s so I assume he knows what he's doing. He's got a pretty big shop and builds and sells engines when he's not doing custom work.
But I was thinking.. why would a machine shop need the flywheel to balance the crank if the rear is externally balanced by the flywheel itself? Shouldn't the front of the engine be neutral balanced by the shop and then you can add any stock weighted flywheel to the rear? Because a lot of people take their blocks to get machined and assembled and I don't think I remember having to take the flywheel to the shop also. But I could be wrong
I imagine you would take the flywheel if you want everything front to rear, zero balanced though
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
I am not a machinist nor do I balance rotating assemblies....with that said it is my understanding that a external rear balanced motor the machine shop bolts on the flexplate or FW when they balance the rotating assembly. Your shop has rebuilt a few LT1's so they should know what they are doing. The stock FW and clutch should work fine
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
The technical nit pickers will insist the LT1 is internally balanced. The weight on the flywheel/pressure plate is only there to compensate for the metal that is removed from the rear of the 1-piece rear main seal crankshaft, so it can be assembled. Some info in this post:
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Was installing the timing cover today and it kept rocking back and forth, not seating properly. So I took a closer look and found this:
So from what I understand based on what I read shoebox, It looks like the long pin sticking out is from a 95-97 cam but the cam sprocket/timing set is for a 94 (which is my car)
Is my assessment correct?
If so, I am thinking there are 2 options:
1) Get the 1994 cam out of my old engine and throw it in there and everything else should work including that timing set.
2) Change over to a 95-97 setup, which I will need to get a 95-97 timing cover, 95-97 timing set, 95-97 timing seals, 95-97 optispark.
Option 1 is cheaper... and if my assessment is correct.
I didn't even notice when I bought it because when you look at the engine straight on, you can't tell how long the pin is. I saw the spline in the picture and assumed it was the same as mine.
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Actually, I'm reading that the cam dowel pin is replaceable so it looks like the only difference between my old cam and the new cam is this dowel pin. I won't have to change out the entire cam.
I'm going to take an angle grinder and shave it off to match the shorter dowel pin length tomorrow.
So I guess from the factory the spline driven models (94 and before) had smaller holes in the actual cam.
But luckily even if the new engine has a larger hole in the cam itself it should still work with my smaller spline driven Opti.
My timing cover has the smaller hole so it looks like the only thing that's different and needs modifying is the dowel pin length is a little too long to clear the timing cover itself.
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Originally Posted by Injuneer
There’s a photo comparison of the hole in the end of the cams in the article I linked.
Yep I saw that. I could still use a 94 spline driven opti with the newer cam with the bigger hole in it right? It's not like the hole is used to driven the opti so as long as it has clearance, shouldn't it not matter? From what I can see, aftermarket cams don't seem to differentiate
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Originally Posted by ridiqls
Yep I saw that. I could still use a 94 spline driven opti with the newer cam with the bigger hole in it right? It's not like the hole is used to driven the opti so as long as it has clearance, shouldn't it not matter? From what I can see, aftermarket cams don't seem to differentiate
Yes, the cam hole size can be bigger. Aftermarket cams are all of the larger hole size, so they can be used on any year and they don't have to manufacture two different cores.
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Originally Posted by shoebox
Yes, the cam hole size can be bigger. Aftermarket cams are all of the larger hole size, so they can be used on any year and they don't have to manufacture two different cores.
Re: Looking to buy a 94 Z28 with head gasket problem, what to look for?
Got the timing cover on, oil pump, drive all that stuff. Torqued down the oil pan but I'm not 100% sure where the stud goes on the oil pan
I see this picture, I have the service manual but it's not clear where #83 stud is supposed to go:
Why is the picture showing the stud on top of the bolt?
I swear from my memory, the #83 stud goes into the 4th hole from the front on the passenger side but I saw this guy's video and he put it in a different location (3rd position from the back, passenger side):
I don't remember there being anything attached to this stud. Anyone can recall off the top of their head the correct position for this stud?
Hoping to get most of the accessories cake in grease cleaned and on the engine and sitting on the K-member by tomorrow so I can have it in the car by the end of the week hopefully. Waiting on the optispark cap and rotor I ordered
10-13-2018, 01:29 PM
