Great info guys ... I'm sure i'm wrong on this .. Why am I thinking the block deck hight is higher on a 3.8 then a 3.5 and the intake will not work .. No...???

It is taller but not by much. There is a upper and lower manifold and I think you can bolt 74 intake right up to the 75 lower. I'm not 100% certain as I've been digesting a lot of information over the last 3 days but I did read one swap thread where all the guy did was swap valve covers and peripherals. It wasn't a great write up. I haven't seen a very thorough write up done, step by step and with pics. After researching V8, Vortec and 6g75 swaps the latter definitely seems the most cost effective and one of the simplest upgrades I've seen. You have to love bolt on's. Heck I would even be tempted to use the 3.8 intake runner as well if I can make it work. They are a thing of beauty and flow much better than the 3.5.

I realize we are talking about the 3.5L SOHC 6G74 engine here, but I was looking at something rather odd the other day that reminded me of this thread. With all this talk about using the bottom end only and using the same cylinder heads, I was thinking about the 3.0L engine and those cylinder heads. It dawned on Clearwater Cylinder heads lists the same cylinder heads for the 3.0L 6G72 engine and the 3.5L 6G74 engine. Here, see for yourself and take a look.



With that being said, couldn't I install the 3.8L 6G75 into my Raider??? If so, that would result in a power increase, a little over +85HP. Guys, am I way off here? I have fist hand experience with the blocks from the 3.0L SOHC & the 3.0L DOHC, but I don't know if that is the same with the 3.8L SOHC.

Interesting thought. Anything is possible right? As long as you have the proper sensors for the ECU I would think it's a no brainer. As far as heads are concerned I don't know why you wouldn't want the 75 heads. They help the thing breath. The valves are much bigger and flow almost as much as a LS1. Of course, I'm just coughing up what I have read but I read it from people much smarter than me. Custom headers and exhaust would really make this engine nice especially if you can fit the 75 manifold. Heck I wouldn't even mind going with a stand alone ECU and toss a MIVEC engine in there but I don't know if I have the patience for it.