[Buick] Ecotec Plenum on Buick?

[anarklov3r]

Hey guys, just had a random thought. Got a VN wagon that the parents are using (not very often might I ad) and have access to a VX intake manifold and plenum.

Now, i've heard that the ecotecs and buicks indeed use the same block and configuration (apart from a few small differences in electronics and sensors). My thought process is, people are able to replace buicks with ecotecs running the same computer since the blocks are the same, whats stopping me from running a ecotec plenum and intake to hopefully get some more power out of this old engine if thats (mostly) the difference between the two?

I've tried searching and found nothing on this. Does anybody know of anybody who has tried this?

I know this is mostly pointless, but it's more something "why not, I wonder if it will work?" than "zomg cheap mods"

Any input is appreciated!

 

[elmaso]

actually there are many differences between 3800 SII and the ecotec.
one of which is that a ecotec manifold is secured by 12 bolts when a 3800 is held by 10, and depending on the series of VN, the thermostat is at the back of the manifold.

not just a straight swap, a little more though into it, probably could be done, but i haven't seen it.

 

[anarklov3r]

Ah cool thanks. I hadn't put much time in to it to be honest, I guess if I actually looked at the two side by side id find more things that wouldn't work. Just had an idea while I was at work

Thanks for the input!

 

[HoldenOn]

I'm sure it could be done, but would probably be way too much hassle for what it would be worth in the end.

 

[seq4x4]

Put a v8 tb on it.

 

[westerlybreeze]

The Ecotec block has 1" shorter deck height (shorter conrods and different compression height pistons)
Which would mean the inlet manifold could be made to fit with custom wedge spacers.. :unsure:

Hasn't someone fitted Ecotec heads and cam to a Series II block?
Do they bolt on and galleries line up? :hmmm:

Also the two motors require a different tune. I know the Ecotec with an early 808 ecu can have too much ignition advance.

 

[elmaso]

Piston height of the ecotec and 3800 are diffent, so I'm guessing you'd need to do a bit of ####ing about to get it happening.

 

[westerlybreeze]

Piston height of the ecotec and 3800 are diffent, so I'm guessing you'd need to do a bit of ####ing about to get it happening.

The Ecotec pistons protrude only a fraction.. 0.10-0.020" I think, which reduces 'squish' = improving combustion.
Same can be achieved by 'decking' the block. A standard head gasket thickness is 0.064".

So it's more about the head bolts into the block and water/oil galleries lining up.
The Ecotec valve configuration is in a different order to the earlier block. So a Ecotec cam would be required, as well as a custom manifold.

'Why?' you maybe thinking..
The Ecotec heads breath better and there's more aftermarket bits available for them.
The earlier blocks have a 1" taller deck height = 1" longer conrods.. which are better for revving. As well as more room for stroker cranks
The Ecotec has a reduced deck height to shorten the conrods = a lighter rod + faster piston speeds = more mid range power at the expense of side loading the piston causing more wear.

 

[elmaso]

Well you learn something new every day! haha