93 GM 1/2 ton 5.7 to 6.0L LS1

[Rebel37]

I am getting ready to start my 5.3 swap into my 1994 silverado. Like you, i have the 1st gen 4L60E. I was told with these trans we need a different flexplate to adapt to the newer engines. I believe it was because of the shorter torque converter bolts.

That is possible, i can't say for certain, though. But in my case, if i do the conversion with both block and trans, that won't be a concern.

[LeadSled96]

Oh, okay. How much of a parasitic loss?
And this probably sounds like a stupid question, but by swapping in the LS, is it possible to convert my OBDI to OBDII system in order to tune it with a programmer?

Probably a 20HP loss depending on set up of course I think you can stifle that a lot with a good stall. You can wire in a OBD2 port to be able to tune it. You will have to remove the old port and bring the proper wires from the PCM to the port but theres only a few wires needed to do it. You can get the port off Ebay pretty cheap.

[Rebel37]

Oh, okay. How can I tell what range stall converter I'll need?

[pl4yboy]

Oh, okay. How can I tell what range stall converter I'll need?

Diameter is more important that stall speed in reducing the loss. Look at a 9.5" converter.

[Rebel37]

Hmm.. okay. Another question, I am debating on doing some upgrades on this motor as well: cam, possibly heads, simple stuff. would it be wise to build the LS first while still runnign my current 5.7 while getting the LS up to par and tehn swap it in? Or would this make it more difficult for the tuner?

[LeadSled96]

Hmm.. okay. Another question, I am debating on doing some upgrades on this motor as well: cam, possibly heads, simple stuff. would it be wise to build the LS first while still runnign my current 5.7 while getting the LS up to par and tehn swap it in? Or would this make it more difficult for the tuner?

I would leave the old motor in and have the LS built prior to install. Its really just preference though. Most tuners have a package to allow you to email them logs so they can dial the base tune in further. as long as you buy the apropriate tuning package you can do it either way with no difference. The only advantage I see is that if you should hit a snag in the build you arent kept from having a running vehicle until you fix the snag ny doing the build out of the truck.

[Rebel37]

Right. And that's kinda where I'm coming from. Plus if I for some reason decide to back out from the install, I've still got a motor/trans I can sell for a good price.

[Rebel37]

Okay. Odometer just hit 200k miles last night and as far as I know, it's still go the original 5.7 and 4L60E trans and still runs great. I don't doubt it'll go another 100k, but I'm hopin to get all my research done my the end of this year and start the swap summer of 2013 if possible.