labrick2006

Ive done lots of research on here and im still abit confused about a few things. I already have the gen lll motor put together with a 58 tooth reluctor pressed on the crank. My question is about the cam and knock sensors. Which cam do i use since this motor is going in a gen lV truck? Do i use the gen lll since its a genlll block or do i use the gen lV cam? Aslo the knock sensors are on the top of the gen lll vs the side of the gen lV. Ive seen the adapter harness but they are for when you are putting a genlV in a gen lll which is the opposite of what im doing.

Mercier

iTrader: (15)

The presence of a rear cam sensor on a gen III cam won't hurt a gen IV but you need to use the gen IV cam, cam gear, front cover, sensor so that you can get the proper front cam sensor signal. 58x crank systems also use 4x cam gear and sensor so I don't see a plug and play upgrade path for gen III rear cam sensor in a 58x setup.

The knock sensors are different enough that you should run the gen IV sensors IMO..find a good place on the sides of the block if you can. I went reverse recently; gen IV engine with Gen III PCM/harness and I used the gen III sensors in the outboard locations(drilled/tapped).

You still might need a little custom tuning to get the knock sensor gain/sensitivity dialed in just right.

labrick2006

I still have the gen lV motor that came out of the truck so i was planing on using the front cover and sensor from it. I just wasnt sure on the cam i would need. For the knock sensors your saying it would be best to drill and tap the gen lll block to accept the gen lV sensors? And thanks for the help

Mercier

iTrader: (15)

If there are holes down there that will work. IIRC, the gen IV uses a smaller bolt than III. From III->IV I had to enlarge a bit and tap. I'm sure a good tuner could make the gen III sensors work but of course they are in a bad spot and end up corroded pretty quickly due to moisture getting in there.

labrick2006

Very true about them getting corroded. Thanks for the help

tech@WS6store

iTrader: (2)

You will have to drill and tap. there are a few bosses on the engine down low to do so...namely along the pan rail. you will need a 4x cam gear. if you get a performance cam will determine if you need a 1 bolt or 4 bolt. if your gen4 had it is better to be rid of it and replace with normal ls2 front cover and 3 bolt 4x cam gear with performance cam.
We can get you any or all of the parts as well as the tech info to make it work. ive done my fair share of both gen4 > gen3 and gen3 > gen4 swaps.