VN V6 conversion to 304

[rhin135ryan]

I’m 18 and have a v6 vn 3.8L and am leaning towards swapping it with a 304 5L. I am new to this forum, and do apologise if a similar thread has already been made. The main questions I have are;
Which engine would be more reliable, a decently modded v6 engine or a slightly modded v8?
In terms of performance, would a 5L offer more than 3.8L modded? I assume it would but better safe than sorry.

I have heard that the v8’s are made bullet proof but would like the options of people who know these engines better than myself. Engine swap work can be done at home by myself and dad so price isn’t too much of a worry.

Cheers and apologies again if a thread already exists similar to this.

 

[Commo64]

I'd say to just keep the 3.8 mostly stock in your VN as it's already a handful, especially for a new driver like yourself...

 

[someguy360]

Hows your mechanical skills and knowledge?

Theres a lot more to the conversion than simply taking the V6 out and putting the V8 in.

You need to do:
* K frame
* Mounts
* Exhuast
* Wiring loom
* ECU
* Transmission
* Cooling system
* Alternator
* Power steering pump
* all associated bracketry etc (none of the accessories of the V6 is interchangable with the V8)

The best way to do these conversions is to buy a complete donor car thats been wrecked or damaged and swap everything over. You'll spend forever (and a fortune) trying to piece every single nut and bolt together that you need.

 

[the_boozer]

you'll be buying A wrecked v8 to get all the parts required. you'll get bleed dry by tossers buying all the parts you need. Nothing is bullet proof thats another wanker phrase as far as old cars go .

 

[MikeC]

The 304 is close to bullet proof, mine's done about 340, 000Km but as someguy360 said, the changeover not a simple job. Personally I'd drive the V6 until I could afford to buy a 304 outright. That will also give you some experience of how hard it is to get good parts, especially good body parts, for these old cars that are getting increasingly rare.

 

[losh1971]

I have heard that the v8’s are made bullet proof but would like the options of people who know these engines better than myself.

Depends on the size of the bullet.

 

[losh1971]

$5k will buy you a complete donor vehicle. The engine will likely need some repairs as most do. You would need some skill to fix the common problems AKA rear main.

 

[someguy360]

The engine will likely need some repairs as most do. You would need some skill to fix the common problems AKA rear main.

Especially when it's a crank out job on those engines.......urgh rope seals

 

[Commo64]

As others have said, this isn't a cheap conversion and it's not very simple... The 3.8 Buick V6 (Mang mang) is a reliable engine as well, and is known to be a bit of a handful to drive especially in the wet, so make sure to invest in a good set of tyres and drive carefully... I'd just enjoy the 3.8 and then do the 304 conversion once you have the funds and the driving experience...

 

[gtrboyy]

$5k will buy you a complete donor vehicle. The engine will likely need some repairs as most do. You would need some skill to fix the common problems AKA rear main.

I wish!!! Otherwise I'd buy one to keep as a donor car for future project or conversion...pre-covid yes but still hasn't come back down to realistic prices otherwise I'd be buying 2k-3k long blocks to gamble on for 355 rebuilds.

Stock to mild 304 will still be on slow side but will sound awsome when you're out cruising or want to give it the occasional belting...

A lot varies on budget,your skills & what purpose car will be....simplest would be to find complete vn/p setup for plug n play hardest would be vt 304 as many different parts & wiring crap followed by vs for wiring differences but bolts in.