IMO the old saying is still true, no replacement for displacement when it comes to low end torque

Wonder if that's what the new engine mount ordeal is in this 409 situation?
I think that's one of the keys in the new Z06 is special mounts to combat the vibrations.

Fords 2015 GT350 had flat plane also.
If I remember right that engine got nixed for timing chain issues.

I would say yes. Otherwise there is no reason to do it.

But also, at higher engine speeds, the short exhaust runners get closer to the tuning window. I noticed some wake boats have a true SBC cast header with a cat integrated.

Maybe reversion improves too?

Doubt it.

I would bet it is.

Didn't Chevy go to Merc to design the blown 427 that went in to the reintroduced ZR-1 about a decade ago?

Thanks. Brad.
(937)545-8991

No that was the C4 ZR1, DOHC

IGetWet,

But there WAS that collab, then. So I’m not hallucinating.

Thanks. Brad.
(937)545-8991

no

Merc built the C4 LT5 because GM didn’t have a manufacturing line for it at the time.

Merc probably cribbed the blueprints for the qcv4 imo

A 400hp 377/383 is a walk in the park with cheap internals and exhausts.

Soeaking of which, The exhaust pic’d on this 409 looks like your normal sbc merc msnifold riser.

if this 409 ebds up being the newer Vette engine, thst would better explain the price tag, but again, 400hp sbc for +30k ? Come on. Ridiculous.

Why pay $8k for a killer $4k gamer computer that only plays Pong and Asteroids. Great games, but $30 console will produce same results and still play them forever without dying.

Hopefully there is more info they are holding back. This is nutz. Imho again, they are really trying to go mostly outboards. They are oretty much theircslready.

Former C4 ZR-1 owner x 2 here. GM went to Merc for its experience working with aluminum.

To me it seems like a bored and stroked small block (Yes I'm sure it is the block mercury claims to have designed themselves, which sure looks like a smallblock to me), a flat plane crank thrown in, and a Holley throttle body.
Hard to justify that price...especially for 400 hp.

I’d just deal with the catalyst system on the main Mercury branded 8.2L for that price…you can get the brand new dressed 8.2 MerCruiser Big Block with ECM and all for $22,000 with a cable controls option. I think this is solely for those afraid of cats, with how cats run 300k miles in vehicles I’ll take my chances with cats before I spend $30,000 for less power and torque. MerCruiser will also sell you the 8.2L long block for $15,000 and you can skip the cats and use your accessories. Not sure who will be buying this interesting piece…

I would not do any of the above when several companies make new 7.4 and 8.2 engines with DART blocks and forged rotating assemblies for less $$ than anything from the mothership.