Is there a performance upper intake, preferably metal, to replace the plastic upper intake on the L36 3800's? I know there's this high velocity insert from ZZP, but that just replaces the runners of the existing plastic upper intake.

 

To the best of my knowledge, there is no off the shelf, bolt on performance upper intake. The only way to improve the performance is what you mentioned about a ZZP HV3 insert.

Now, you did ask about metal, there is an option there, requires a little modding. GM had a Series III L26 3800. You can swap the aluminum upper intake from that on to a Series II engine with minimal issues. I actually did that with my Monte mostly for looks. Here is a thread with a lot of pics:
https://montecarloforum.com/forum/fw...c-heavy-48949/

 

The reason I'm looking into this is because I plan on turbocharging my Monte, and, although my reason is completely unfounded, I don't quite trust a plastic air intake. Also, I've seen the "series" bit regarding the engines, but I'm not quite sure which my engine is.

 

The only real down side to the plastic UIM is the coolant passages that run next to the EGR stove pipe. That tends to be the common fail point. You can address that a few different ways, best being stopping the flow of coolant to the throttle body. Plenty of people have used it with turbo builds.

But I understand, the aluminum is a much more durable material and goes for the long haul! Lot less to worry about. You could also upgrade the plastic valve covers by getting the aluminum ones used on the 3800 powered Camaros and Firebirds of the late 90's.

If you decide to do any of this to pretty up the engine, you can also get a stainless bolt kit for the UIM/LIM from these guys:
https://alloyboltz.com/product-categ...y-v-6-engines/

I sent them the hardware a few years back and they matched it up to a nice kit.

 

If it must be a 'performance' intake, I only see two options:
-Stattama made a sheet metal intake years ago. As far as I know, they don't make it anymore. You could try to call up ZZP and see if they could get more made or you could try and search for a used one (although I don't think they made many as they don't come up for sale often).
-The alternative is to find a performance fab shop and have them make you a sheet metal intake. That could either be a replica of the Stattama one or even a complete one off depending what you're looking for. This isn't a cheap route though, I bet you don't get out of it for less than $1k.


If your only concern is reliability, you shouldn't be concerned at all. A stock L36 manifold has been in the 9s making WAY more boost and power than you probably plan to.

If you think about it, it's not really adding any additional stress unless you run a ton of boost. If a car is idling and manifold pressure is 5 psia, that's a 10 psia delta from ambient. Generalizing a bunch, adding 10 pounds of boost (15 psig / 25 psia) is still a 10 psi delta so the forces are exactly the same, just in a different direction. So say you've got a basic 6 or 7 psi non intercooled kit, the manifold is actually more stressed at idle than it is at WOT (in terms of handling the pressure from boost).

As the factory adds in a safety factor, it can certainly be pushed past 10 psig. Plenty of people have run then to 20+ without issues.


If you absolutely had to have a metal intake, and were ok not getting an aftermarket performance one, there are only a few options that I see depending on your budget and where you plan to route your intercooler's return line (if you plan to run an IC):
-L26 intake
-M90 case blocked off (would require a head/LIM swap)
-Fbody intake (passenger side inlet)
-Australian intake (radiator facing inlet)

Personally, if youre serious about going turbo, I wouldn't waste a dime on any of that stuff and would instead put that towards a fully built trans so you can actually enjoy it.

 

Side note, I have a metal series 3 upper intake manifold I can sell you if you are interested.

 

I'm looking to get a replacement manifold for the 3400 engine. Would the one you're selling fit that ?

 

It wouldnt fit.. 34 and 3800 intake manifolds are very different.

Milzymotorsports still does performance 3400 stuff tho hes kinda expensive.

 

Larry, this would be best as it's own thread not piggy backed on to someone else's.
The 3400 is a completely different engine as mentioned. Typically the aluminum intakes don't go bad, they just need cleaned. If you need a replacement for a 3400, just about any autosalvage yard should be able to assist. One side note, GM had mid generation changes based on what year 3400 (but I believe that was seen more in the Grand Ams than the Montes, but don't quote me there).

If want to post a parts wanted ad, please use the classifieds section of the forum. You will need to be a full member to do so (this requires being a member for 5 days and having 10 posts (which is pretty easy to get to, just chatting in the blogs can help that).
https://montecarloforum.com/forum/fa...cf_full_member