a bunch of OPTI / timing chain BS!
05-07-2008, 07:10 PM
#1
Staging Lane
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a bunch of OPTI / timing chain BS! ok here is what i have, 93 z28, 180k on the clock(might be 60k idk), slack in the timing chain, and a lt4 hot cam kit for a 95+ (longer cam pin, summit sent the wrong one). so i was looking into buying a msd kit (msd dist., 6al, etc..) and swapping the timing chain while im putting the vented opti, msd, elec. waterpump and cam in. well heres a few ?'s i got.
will the 95+ msd kit still plug into and work in the 93 computer?
will the cam with the longer cam pin work with a 93 opti? (if i dont get the msd kit)
do i need the 95+ cam timing gear since im going with the elec. water pump?
i have been searching and answered alot of my ?'s, but these i couldnt find.
will the 95+ msd kit still plug into and work in the 93 computer?
will the cam with the longer cam pin work with a 93 opti? (if i dont get the msd kit)
do i need the 95+ cam timing gear since im going with the elec. water pump?
i have been searching and answered alot of my ?'s, but these i couldnt find.
Last edited by 97bagds10; 05-07-2008 at 07:32 PM.
05-08-2008, 11:41 AM
#2
On The Tree
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Ok, you can use the 95+ dist. with your computer, but youre gonna need a 95+ opti pigtail that goes from the opti to the plug in about midways back on the side of the intake (passenger side) And a 95+ timing cover. Since youre runnin an electric water pump anyway, I would get a double roller timing chain for a gen 1 sbc roller motor. saves you alot of cash. Just leave the WP drive gear off the block (2 torx bolts) and get a freeze out plug to seal the WP drive hole in the timing cover. Thats what i did on my 94. Im not sure if the 93 opti will work on the later model cam or not. Hope this helps you out!
05-08-2008, 10:14 PM
#4
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Your answer is ambiguous. No LT1 ever had a "splined camshaft."
The 1992-1994 LT1 used a splined camshaft timing gear, which used a splined shaft, which plugged into the back of the splined 1992-1994 Optispark. Thus, vehicles with the pre-1995 Optispark are limited to the factory-style cam gear / timing set in order to have a functioning ignition system.
The 1995+ Optispark requires an elongated camshaft dowel pin (.620"~.680"), and an enlarged cam snout opening to accept a stabilizer shaft on the rear of the 1995+ Opti. Since he'll have an LT4 hotcam, that will not be an issue, as the LT4 hotcam is a 1995-style cam. Keep in mind that a 1995 cam CAN be used with a pre-1995 Optispark, so long as the dowel pin is shortened to factory 1992-1994 specs (.310"). The reverse is not necessarily true, due to the cam snout opening, though some claim that is not an issue.
1) Are you looking at complete MSD Optisparks, or just their cap/rotor kits? Assuming the former, the short answer is Yes. Few thoughts though:
MSD makes a kit for both pre- and post- 1995 cars. So, you have the option of getting a kit designed for your 1993, though I would recommend getting the 1995 version for more options in regard to timing sets. Also keep in mind that the MSD Optispark includes a permanently-mounted electrical harness, so that'll be one less thing for you to buy. When converting to a 1995+ Optispark harness, you might need to cut off some alignment nubs inside the factory Opti electrical connector on the intake manifold for them to mesh properly
Again, just make sure you make up your mind before you purchase anything, because the pre-1995 and post-1995 setups require a different set of parts to function properly. If you decide to go with a 1995+ Optispark, you must match the parts. That means getting the 1995+ optispark, timing cover, electrical harness, vacuum lines, etc. -- things that the 1993 wouldn't need.
2) Yes, so long as you shorten the dowel pin to 1993 specs (.310"). I ran the Hotcam on both a 1994, 1995, and a mish-mash/frankenstein 1994+1995 Optispark I made. Just maintain the correct dowel length for whatever you're running.
3) No, with an electric waterpump AND a 1995+ optispark, you can essentially run any 1987+ SBC timing set. It does not need to be LT1 specific. I personally run a Cloyes 9-3145 SBC double-roller.
The 1992-1994 LT1 used a splined camshaft timing gear, which used a splined shaft, which plugged into the back of the splined 1992-1994 Optispark. Thus, vehicles with the pre-1995 Optispark are limited to the factory-style cam gear / timing set in order to have a functioning ignition system.
The 1995+ Optispark requires an elongated camshaft dowel pin (.620"~.680"), and an enlarged cam snout opening to accept a stabilizer shaft on the rear of the 1995+ Opti. Since he'll have an LT4 hotcam, that will not be an issue, as the LT4 hotcam is a 1995-style cam. Keep in mind that a 1995 cam CAN be used with a pre-1995 Optispark, so long as the dowel pin is shortened to factory 1992-1994 specs (.310"). The reverse is not necessarily true, due to the cam snout opening, though some claim that is not an issue.
1)will the 95+ msd kit still plug into and work in the 93 computer?
2)will the cam with the longer cam pin work with a 93 opti? (if i dont get the msd kit)
3)do i need the 95+ cam timing gear since im going with the elec. water pump?
2)will the cam with the longer cam pin work with a 93 opti? (if i dont get the msd kit)
3)do i need the 95+ cam timing gear since im going with the elec. water pump?
MSD makes a kit for both pre- and post- 1995 cars. So, you have the option of getting a kit designed for your 1993, though I would recommend getting the 1995 version for more options in regard to timing sets. Also keep in mind that the MSD Optispark includes a permanently-mounted electrical harness, so that'll be one less thing for you to buy. When converting to a 1995+ Optispark harness, you might need to cut off some alignment nubs inside the factory Opti electrical connector on the intake manifold for them to mesh properly
Again, just make sure you make up your mind before you purchase anything, because the pre-1995 and post-1995 setups require a different set of parts to function properly. If you decide to go with a 1995+ Optispark, you must match the parts. That means getting the 1995+ optispark, timing cover, electrical harness, vacuum lines, etc. -- things that the 1993 wouldn't need.
2) Yes, so long as you shorten the dowel pin to 1993 specs (.310"). I ran the Hotcam on both a 1994, 1995, and a mish-mash/frankenstein 1994+1995 Optispark I made. Just maintain the correct dowel length for whatever you're running.
3) No, with an electric waterpump AND a 1995+ optispark, you can essentially run any 1987+ SBC timing set. It does not need to be LT1 specific. I personally run a Cloyes 9-3145 SBC double-roller.
05-08-2008, 11:39 PM
#5
why dont you just send your hocam kit back and get the right one from summit?? it would make it a ton easier then trying to mis match parts here and there. Send it back get the right one and get the msd cap and rotor kit for your car which has a vent.
