Okay, so I am going to get the LT4 hotcam kit. I have a 94 corvette and I want to replace the timing chain as well. I would like to have a true double roller design (was looking at the LT1/LT4 extreme duty timing set). With the extreme duty timing set it says I have to upgrade (to 95 and up) timing cover, optispark, water pump and a few other things and with those things it will double the price of the LT4 hotcam kit. I don't know if I want to do that.

Can anybody help? Can I use a double roller without changing the opti and h20 pump/timing cover? What brand and what specific timing set? What do I have to change with the new timing set?

Thanks and sorry for all the questions. I just want to get everything sorted out first before I start going crazy ordering.

 

The only upgrade from an original LT1 chain that you can use and maintain your water pump is the GM Extreme Duty LT4 chain. Which will still require you to upgrade to the newer timing cover and opti.

If you want something like a Cloyes True Double Roller then you must use an electric water pump. Only the few GM chains have the provision for the gear driven water pump. So if you really want to upgrade to this type of chain at the very least you will need the timing cover, the opti, the new opti wiring harness, electric water pump, new cam with provision for new style opti (hot cam will work just fine)

Been there done that, explained that many times. That's the short version if you want more info I"ll be happy to provide it, but I'll save the typing if you don't want to hear it.

:cheers:

 

Okay, so if I get the extreme duty timing set, I will need to upgrade all those things.

If I want a cloyes true double roller timing set, do all I have to change is the water pump to an electric? or are you saying that I have to do opti, cover, harness, and electric water pump to get the cloyes double roller?

Here is the thing: I do want to get the LT4 hot cam kit and I want to upgrade the timing set, but it is $230 dollars for the extreme duty timing set, $280 for an opti spark, $70 or so for the cover (from gm). That is $580 when the hot cam kit alone is $475.

Oh and will my stock timing set handle the higher RPMs (in case I will upgrade all that stuff later)?

Any help?

 

Even if you get the Extreme Duty Timing set you will have to upgrade your opti which will in turn require a new timing cover. You will be able to run your standard water pump without any troubles.

If you go with a double roller you will give up your water pump drive so you will have to do the above AND the water pump, no way around it.

The timing chain and the water pump would be money well spend. In my opinion the GM LT4 chain isn't that special. Given the choice betwee the two I would take the double roller (which I did because I already had the electric water pump anyway)

You don't have to do any of it. Your timing stock timing set will work alright. I ran my stock timing set with my hot cam, routinely turning 6300 rpm's and I didn't have the first hint of a problem. How many miles are on the car? If your stock chain is healthy, you don't have to have the upgraded ones.

I will however give you a warning. The Hot Cam will work with either chain / opti configuration. I put the hot cam in with my stock chain and opti originally. The cam has a pin that it uses to align with the timing gear. In later models this pin is longer and actually drives the opti as well. When you install the hot cam with an older opti you simply take a hammer and tap the drive pin further into the cam. Later when I wanted to use a different timing set, which then required me to go with the new opti and timing cover (already had the water pump) I could not extend the pin back to where it needed to be. I had to remove the cam and replace it with a new Hot Cam before it would work. Some people have had luck extending the pin back out, but I sure didn't.

So basically you are looking at stock parts now and stock parts for a long time unless you want to pull the cam all the way back out again later, and possibly have to replace it. That will be a serious headache down the road, and you can throw in an additional $180 in there for a new cam if needed. Or you can bite the bullet now and buy everything you need to get the timing set you want. Then with any luck you would never have to touch it again.

If I had to do it over again I would find a way to do it all at once, the first time. If the budget doesn't allow then I would go with the stock stuff, which would be the absolute easiest thing.

 

Thanks again for all your help.

I believe that I will probably wait and get all the parts to do it at once. That way I can upgrade the optispark (since I hear they have problems...haven't experienced any) and the water pump would be a good thing. I will probably go for the double roller chain since it is working well for you and is slightly cheaper.

Thanks again.