1UZ lower manifold (didn't Ed start this thread?)

[mullett]

After much gentle coercion from Rudi (in the form of subtle slights on my sexuality) I've started having a serious think about making a new intake for the 1UZ. I'm sure I read a thread that Ed started a while ago about making a generic lower manifold, but for the life of me I can't find it. What I'm thinking is:

Two seperate manifolds, one for each bank. Runners curl around so that the plenum on each side is sitting over its respective cam covers, with the ITBs plates vertically at the end of the runners, and bellmouths inside the plenum. At a guess this would give me a runner length similar (maybe slightly shorter) than factory, with the bonus that I can increase the runner length if need be, and it avoids too many clearance issues to the bonnet. The big advantage (in my eyes) is that it leaves the two flange plates seperate from each other, avoiding dramas getting them to sit perfectly level and flat with each other.

What I'm really wondering about is:

Runner size (length and diam) At this stage it'll be using factory cams, with a possible upgrade to some mild street cams later.

Suitability of throttle plates: I'd really like to get two silvertop 4AG plates...if I can find them.

Peoples experiences with the intake side of the 1UZ: are the gains there to be had?

-RM

[Duk]

Two seperate manifolds, one for each bank.

I don't think this will work well on a crossplane V8.
It works well on 60* V6's because they alternate firing event: left bank - right bank - left bank - right bank. There is an even 240 crankshaft degrees between induction strokes for each manifold.
With a crossplane crank V8, there isn't equal left bank - right bank firing of the engine and that's why most of them breath from a common plenum chamber.

[CrUZida]

Are there gains to be had?
Depends, are you planning on spending another $5k+ on the rest of the motor (heads, cams, pistons?), or just the manifold?

If its just the manifold, then unlikely. Evidence produced thus far has been minimal gains for a manifold alone.
NEEDS to be used in conjunction with other stuff.

[mullett]

And once again, I'd rep you if I could...seems I've given both of you too much love lately.

I wasn't intending to build the rest of the motor, it'd be cheaper (and bigger gains) to boost it...even if that would be a bit of an angry-dpi move.

-RM

[mullett]

Having done a bit more reading, especially in v-eight.com, and the best idea I've been able to dig up is:



from this thread:

http://v-eight.com/tech_forum/viewtopic.php?f=4&t=1436

I'm considering making up a jig (it'd need to be fairly solid) and fabricating a few. I like the idea of something that can use the standard top manifold, keeps the engine looking stock and should improve flow. I'm looking for ways to optimise the engine with things that i can fabricate rather than buy...Uni's putting a crimp on my $$$

-RM

[CrUZida]

That was Justen's manifold, I think he made 2, with mk2 being better than mk1.
But he sold both.

[mullett]

Yeah, I haven't been able to find a lot of info, but it's a really neat solution, maybe not as good as a dedicated ITBS manifold, but neat and tidy. Do you know much about what he changed for mk2?

*just realised that the reference in the last post wasn't very obvious...updated!*

-RM

[mullett]

I now have a spare 1UZ! Lasercutting and jigging time

-RM