Hey,

I have a nonvented opti, and i'm doing heads+cam. I am planning on 400+hp after I have completed. I have heard that running a replacement stock timing chain would be a little risky at these power levels. What kind of timing chain can I use? Other than the $600 sets that I have seen, the only other option is a lunati set. Has anyone used this set, or am I totally off the wall with this.

Also, I need new injectors. I am deciding between the 30# SVO injectors(more like a 32#er because of the rated pressure), and the accel or other 30# ers. Anyone have any recommendations?

Thanks in advance,
Rich

 

ill just tell you how i am going to do it and leave it at that. my cam is only going to rev to 6100, so im just gonna put a chain on mine and replace the 70K mile lifters. the Lloyd h/c pkg im getting should make about 400rwhp on motor and hopefully around 500rwhp on nitrous. as far as injectors, im gonna run fms 30s because ive always had good luck w/ them in my mustangs.

 

If you are willing to use an electric w/p,you have a lot of choices.If not,the LT4 is a nice roller chain.For the injectors I recommend the SVO 30's.

 

this is a 94 so I cant use the lt4 chain.

 

Why not?

 

btw, you have 2 choices with the lt4 chain+ sprocket sets. 1- is the hd and 2- the "regular" lt4, which costs a bit less. i went with the regular one and had no prob with 6800 rpm shifts, for 20k miles(dont have the car anymore).

 

from what i've heard the 94 opti is driven by a uniquely designed cam gear, which utilizes a splined shaft mounted on its face, most aftermarket chains are designed for 95+, so they will render my ignition useless.

 

I use the Accel #30's and they work great. I think a new stock timing chain would hold up just fine.

 

Ah, no. The Timing Chain and Optispark drives are two totally seperate units. All LT1/LT4 F-Bodies have cam-driven distributors.

 

Spinner -- what timing set is in your car currently? Have you installed that cam in your sig, or are you just getting ready to? I believe you've been given some faulty information regarding timing sets.

The 1993-1994 opti is driven by a splined shaft fixed to the cam gear. The 1995-1997 opti is driven directly by an elongated cam dowel pin (no splined shaft), and the 95+ cam gear has a larger center opening to accept a 'nub' on the back of the vented opti (which passes thru the timing gear to fit in an enlarged 95+ cam snout opening). Because of this enlarged hole on the cam gear, the 93-94 splined shaft cannot be incorporated on a 95+ timing set for use on a pre-95 vehicle. Thus, you wont have a working ignition system on a pre-95 vehicle.

In short, the 1993-1994 and 1995-1997 optispark drives are different, the cam gears are not the same, and there is no way to incorporate a 1995+ timing set into a pre-95 vehicle without upgrading optisparks and supporting parts (timing cover, etc.). The LT4/HD timing set is made for 1995 and later vehicles.

This is why us pre-95 guys have so much trouble with timing sets -- we have very limited options with the unvented, spline-driven opti. The 93-94-specific Lunati set offered by Summit is one of those few options, which is why this thread was started.


If you have found a way around this, PLEASE let us know!!! Otherwise, I'll assume you've been given bad info.

HTH

 

I guess it should also be stated that we have an internally-driven waterpump (no belt/pulley) -- which is again driven by a unique LT1 cam gear with additional teeth on the back to turn the waterpump driveshaft. Some aftermarket 1995+ timing sets are not LT1-specific and do not have these additional teeth on the back of the cam gear. THAT is why an electric waterpump is needed on 1995+ models with said-type of timing set. A waterpump is somewhat necessary for proper operation of the cooling system.

However, the above information is irrelevant to pre-95 owners, because using a timing set that requires an electric waterpump would also leave us without an operating ignition system. The waterpump would be the least of our worries if the car wont run in the first place. If we didnt have to worry about the optispark or the waterpump, we would ALL be using standard SBC timing sets. AFAIK...


Sooo, 94Formula's question is really directed towards the pre-95 owners (as 95+ owners would not have to worry about this problem, nor the Lunati timing set in question, as it will not work on a 95+ vehicle).

THAT BEING SAID, has anyone used/heard anything new about the Lunati timing set? Results?

 

Thanks for clearing that up Alex. Isn't anyone running a high horsepower pre-95 lt-1? Just need some suggestions.

 

Bottom line: if you have the non-vented opti, you must use a stock cam gear. No other gear will drive the opti.

If you only want to convert to a vented opti, then you can run an LT4 or LT4 ED timing gear set.

If you want to run an SBC type set (like Cloyes double roller), you must convert to vented opti and convert to an electric water pump.

 

That depends, Shoebox. Stock style cam gear, yes, but it doesnt have to be THE stock cam gear. The following link has a $550 aftermarket timing set for the pre-95 Lt1. http://www.dougrippie.com/drm/engine_components.htm

Perhaps there are a few other $$$ sets out there. I wish there was a cheaper solution for a hefty pre-95 set, but I really dont think there is. For the amount of the above set, it might be best to just go ahead and upgrade the opti and go that route...

I wonder if anyone has tried to line up and weld the 93-94 spined shaft to a 95+ cam gear... wouldnt that be a nice solution...

 

I'll concede that (I don't know everything ). I was not aware that anyone made a replacement, but $365 just for the gear? Who is gonna buy that instead of converting to vented? Plus the chain is just like the stock design.