a bunch of OPTI / timing chain BS!
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; May 7, 2008 at 07:32 PM.
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.
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.



