timing chain

[rufrider76]

i am in the middle of a an opti project that has snowballed. i put an electric water pump on and while trying to do it correct wanted to remove the shaft coming thru the timing cover. to do so i need to remove the entire cover and the timing chain. i see that the original is expensive because of the need to drive the water pump shaft. i am removing this so can i use any 350 small block timing chain or do i still need a lt1 specific. i was looking and a good roller set up is around 120.00 but anything for the lt1 is way more.

[fastTa]

The Cloyes double roller timing set can be had for $80. It is part number CL-3145. SBC timing chains are interchangeable with the LT1.

http://www.cmotorsports.com/93-97-fb...ine-timingsets

[rufrider76]

so any small block chevy timing set will work. belt drive, gear drive anything?

[Joe 1320]

While others may work, you don't want a gear drive on an LT-1 if you are retaining the knock sensor circuit. The extra noise will get picked up by the knock sensor and give the computer fits.

[rufrider76]

yeah i was exagreating with the gear drive. but am i wrong when i say i think i read a 10 hp gain with double roller chain set. i do not know why you would bit i swear i read it. all i can guess is less rolling resistance

[rufrider76]

wait a minute. i went to the part store and they had the double roller kit on the wall. it has nothing to drive the optispark. the optispadr sharft comes thru the timing cover and into the timinng chain sprocket./ the normal small block timing set does not have this.

[fastTa]

wait a minute. i went to the part store and they had the double roller kit on the wall. it has nothing to drive the optispark. the optispadr sharft comes thru the timing cover and into the timinng chain sprocket./ the normal small block timing set does not have this.

SBC camshaft sprockets are not made with the provision for the camshaft dowel pin which drives the opti. It can be drilled out however. This is why I suggested the Cloyes double roller setup. It contains the right cam sprocket to work with the LT1 cam and opti but w/o the water pump drive, and it has a standard SBC/LT1 crank sprocket.

Comp Cams also makes the Hi Tech LT1 belt drive, however it is not cheap.

[Joe 1320]

yeah i was exagreating with the gear drive. but am i wrong when i say i think i read a 10 hp gain with double roller chain set. i do not know why you would bit i swear i read it. all i can guess is less rolling resistance

A HP increase is possible, but most of the increase will come from the ability to alter cam timing relative to the stock chain. Yes rollers have less friction, I doubt it is 10Hp worth. As the factory chain stretches, it has the effect of retarding the timing. Good for more upper rpm HP, but at a loss of low rpm power. The ability to advance or retard the cam can shift the powerband up or down depending on your desired results. If the cam is a bit too much, advancing the cam timing can help bring the low end power up a bit.

[rufrider76]

i just went with the stock set up. it lasted this long and i hated not replacing it while it was in my hand

[rufrider76]

oksy need help agian. put car all back together and it would not start. take it apart and pull the optispark. look through the hole and see the sprocket from my timing set has no provisions to drive the optispark. i am correct the xam gear should have the grooves the have missing tooth that the shaft from the optispark lines up with. my gear it is a perfect circle. what gives? it has the gear to drive the water pump!

[fastTa]

oksy need help agian. put car all back together and it would not start. take it apart and pull the optispark. look through the hole and see the sprocket from my timing set has no provisions to drive the optispark. i am correct the xam gear should have the grooves the have missing tooth that the shaft from the optispark lines up with. my gear it is a perfect circle. what gives? it has the gear to drive the water pump!

The opti is driven by the camshaft dowel pin. Not sure what you are referring to as far as the cam sprocket.

[Joe 1320]

are we talking opti or water pump drive?

As Kevin described, there is a dowel pin located on the cam gear that protrudes to interface with the rotor base of the optispark. If you didn't align the dowel pin with the proper channel in the opti, the timing will be far enough off to have a no start condition. If there is no dowel pin, the opti will not have any engagement with the rest of the timing set and there will be a no start.

[Injuneer]

LT1 101:

He has a 94. 93/94 Opti's are not driven off the cam dowel pin. They are driven by a splined shaft that interfaces with the cam sprocket.

[fastTa]

Good to know! I stand corrected.

[rufrider76]

okay sothey must have gave me a 95 timing set. okay so where do i get a good roller set FAST