So here is a new one. What are thoughts on a 4.3 vortec swap into a 4th gen 3.4 car. No distributor to worry about. Coil packs same as ours... I think it could be done. Do you?

 

Yes it could be done. It will be more work the swaping in a LT1 and you will still need a V8 donor car (frame/trans).Computer would be a nightmare to get right. The 4.3 is a truck motor you will get owned by a 3.8.

 

wow and it used to be a truck motor was the same as a car motor with a little more power. so the 4.3 has more tourque? thats interesting. i use a buick 231 for a pot pump and it has great low rpm power. pump puts out over 200 lbs of water pressure just like a v8 and is smaller. found a 4 barrel manifold for it along with extra heads at a local yard so i could use a cheaper carb and have extra heads. 2 barrel was way big bucks and had to rebuild yearly.

 

As a general rule truck motors are design to run at low RPMs. The heads are designed to speed the airflow up which works below 4500 RPMs. The Cam is designed to match that. The same design that speeds up air at say 3500 RPMs will normally choke a engine out a 5200RPMs. Thats why you can get big block truck heads by the dozen. Unless you do porting and polishing your much better of getting a set of heads off a car.
If you look how GM applies the 4.3, Trucks/Vans and its bigger car you can see it is designed for torque.

 

I had an 87 Astro van with a 4.3 throttle body pushing 350hp at the wheels, theres a pretty decent aftermarket for them, thats why i was asking. Why would i have to go with a v8 subframe? i cant use modified mounts? i got the fab skills to make it happen...

 

I wouldn't do it personally, might be a squeeze depending on the intake manifold setup you have, then you have to worry about the oil pan. It's up to you, if you can do it, and pull it off, hats off to ya for doing something unique no doubt.

 

i'll take some measurements and let y'all know the results.