Phssthpok

I'm looking over my spare intake as I ponder how I'm going to go about making the adapter plate for my webber, and I noticed that the mounting surface has divided bored, but unerneath is an open plenum.

Can anyone think of any reason I couldnt just open that up into an oval instead of two circles? (Or any particular reason I wouldn't WANT to?)

jimbo74

lce has an adapter plate... its not too expensive either considering they have the maching tools and experience/research doing it.... http://209.250.27.45/m1webgear/Produ...spx?Class=1340

kyle_22r

i don't think it'd be any real benefit -- the holes are about the same size as the throttle bodies on the carb...

Phssthpok

After looking over the manifolds available aftermarket (and seeing just how simple they are) I think I'm just going to fabricate my own with the proper mounts for the Weber.

I can get any thickness steel I want at work up to and beyond 5/8 for the flange(s), and we're currently receiving some 2"x4"x1/8" wall rectangualr tube that I can use for a plenum. For runners I was thinking about electrical conduit bent to shape (and baked in the forge to remove the galvanizing), but I'm undecided on that for the moment. Theres other pipe available at work but none as lightweight and easy to bend as the conduit. I really like the idea of isolating the water passage/thermostat housing from the #1 & #2 runners.

I just need to decide if I want short straight runners, or longer curved runners.


<giddy> I wanna see what this little 4 banger will do with my engnbldr RV head, 268 cam, and a 32/36 Weber! HMmmm... Header suggestions?

jimbo74

from what i have heard, the stock 22r carbs from the later engines flow better than the early ones and better than the 32/36 .... i think kyle told me this.....

kyle_22r

yeah, from what i've seen, the 22R carbs are rated at 326CFM and the 32/36 is rated at 325. i think the 20R carb is 190 :eek:

i think longer tubes are better for power...i'm not carburetion expert but i think it creates sort of a "ram" effect. maybe look into the design of the old chrysler sonoramic intake?

MDNT TOY

Hello ALL
Short runners for top end hp..
Long runners for more low end and Mid range tq.
C-YA!!

Phssthpok

Yeah, I'm all over the Mopar Sonoramic manifolds. (I'm an old school Mopar freak ) The problem with trying to emulate that set-up, is that ChryCo put a LOT of R&D into finding just the right runner length, and volume for a given RPM range and displacement, and they were DEFINATELY high RPM engines. Even though they were long runners they were also very high volume as well.

I do know that lower volume runners will aid throttle response, and low end torque, and that larger volume runners flow better for high RPM power. I just need to figure out the best compromise and then decide on runner length.... short for throttle response, or longer for better torque.

AHhhh.. what a dance my mind's going to be doing..

jimbo74

just but a new one

Phssthpok

MMm..Lessee here....

New manifold = $175+...and the waterneck heats up the #1 & #2 Runner.

Home-made = FREE (except for my own labor), #1 & #2 runners stay cool, and I can custom tailor the powerband.

jimbo74

yes, but home made means way too much r/d and too much time to screw with it... is it really worth trying to engineer it when all is said and done? maybe..... but there is no way to actually try tons of differnt combos, that will add up in price quick....

Phssthpok

What part of FREE costs me anything?

I can get the materials from work at no charge..

jimbo74

hey if your time isnt worth anything... thats fine..... its up to you, as for me i would buy something that someone else put the r and d into it for.... rather then try to make my own and hope it works right and not have to experiment with a billion differnt sizes t ofind the best one....

Phssthpok

For some people weeding a garden is a chore, while for others it's 'relaxation'.

Me?... I like to tinker!