For the guys out there running "Log" style manifolds on the street, Just how much of a PITA are they? I've seen a bunch of them out there but I've never had the opportunity to drive one or have one in where I could get a feel for them. I'm toying with running one on my Vick and it sure would look cool if it would be tolerable. Mostly worried about fouling plugs or burning valves on a longer run. I can set carbs pretty well so keeping things in balance would not be a problem. Planning on 4 Rochester 2GC's. Pic for general look. Not the exact manifold I have in mind. The second pic is just too damn cool not to share..... 4854940[/ATTACH]
I have a Crower U-fab type 8 deuce manifold on my 392. it took a few years to get everything sorted out, and I still have too high an idle, but it runs fine. It is straight linkage, which took a while and a specific order to set idle of each unit. For a few years I kept a dual throttle return spring on it but do not any more and it is still a heavy pedal. The kool factor makes the trouble worth the while, even though it is all hidden under the hood, cause I know what is there.
I know they are basically dumpers so low end torque will suffer a bit. I remember Homemadehardtop57 on here had one on his sport coupe and it ran well with some of the carbs blocked off. Need to give him a call. Saw those pics pics of your shoebox. Too cool for words!
I know 2 guys that have run that set up, 6x2, both used center carb each bank, other 4 for show, they look good/kool. I'm thinking all 6 is a race deal, check with Russ B, he got it working, post #2
I don't understand the mentality behind having 6x2's or 2x4's or 3x2's & only using part of it ,isn't that kinda like wearing a sock in your shorts or girls wearing falsies ? Maybe putting Hemi valve covers on a SBC or a hollow blower case with a carb inside . Just screams phony ...Sorry
I'm also one that dose not care for faking it. I do love the look. I'll try to make one point; @78,I've had the fun of playing with a lot of carb set ups. I started out with 4bbl in 1959,then got 4x2 n moved next , I built a home made log in the 1960s,sold it off,it had some probs back then I didn't like, went back to a 4 bbl. Some years went by,worked on a few other cars that came in to my shop ,got to play with some combos. I really like the look of some log set ups. But often for running around on the street, probs come from 4 factors; Too much cam,to much CFM*/Carbs* for engine and bad linkage design n set*. Added to intake design* I'll start out talking about intakes,factory cast alum logs were not ever made as a street intake.There design is for the racing,an all the ones I played with,had big hole as a runner going to the cyl head,if head had two ports next to each other> they are built for the intake runner to cover both ports/by one big hole=not divided above the head!! That made the logs with that siamese port. On the street we need to idle,best around 600 rpm,an siamese intake porting combed with big cam an lots of carbs are not very happy together. If added to a autotranny vs standard shift,now we got too many things out of happy! So my home made 4x2 log intake on my Ford"Y" v8 Thunderbird, made by cutting up a old driveshaft,was designed back when I built it to have divided runners from the log down to head. It seems to make idle better then any other set ups I've seen running. The homemade parts show 4 kind of Sq. plates=those weld into the drop tube going from log down to head,so each port has it's own flow after log. In a "Y" Ford the two front cyl on right bank fire right next to each other> cross over at idle steels from other cyl,but not if divided.
2OLD2FAST, You would hate my replica champ car. Everything about that build is phony, like the DOHC "Duesenberg" race engine. Or my tub that runs (great) on the center 2V of a phony 3 x 2. I think to make a log intake streetable one could concentrate on making the plenum volume as small as possible, while maintaining communication between the smallish carbs. I have also found it necessary to modify (lean out) the idle circuits. Sock-less in Frenchtown (even I have my limits)
Hate is a pretty strong word , perhaps disdainful would be more appropriate . You are right that I would not be enamoured of it ..
flathead genius barney navarro found that fuel distribution and pooling was a major problem with log manifolds.
If it is just about performance on the street the best choice is almost always a single four barrel, in my case, a spread bore 650 Holley and a well port matched stock intake. On the other hand, that's no fun, so we try other things that not only look cooler but appeal to our desire for innovation. I feel in my case I'm going to get the car running with a set of 2 GC trips on a typical dual plane intake, which is readily available. Once I have a baseline I can play with some different intakes to try to dial in where I want to be. From the replies above I don't see a lot of guys other than Russ B and Dana having much success, so I know it is possible, just not as easy as one might think. By using sort of trapezoid shaped plenums I can minimize the pooling problems associated with this design and by being very careful with plenum volume and runner lenght I believe I can keep runner velocity and fuel distribution issues at bay. There are many design discussions on the net, primarily from the ricer guys who are very into making fabricated intakes. Good discussion here!
Has Anyone made any "chambers" inside the logs to help? Kind of similar concept to baffles in an exhaust. I'm by no means an Engeneer or anything but seems to me airflow and fluid dynamics could all be modified internally and weld the logs back up to appear to be race purposed and traditional while having better "street able " characteristics............ Of course this could be viewed as fake or cheaters rather than innovative. I'm just wondering out loud here not trying to tell anybody they are wrong or offend people. I guess it's all ball bearings nowadays.
Just for the record, I'n place of the Chevy I built for my Vicky I picked up a few Pontiacs and am building in my late night time after the shop projects a decent '66 389 with some good large valve heads that I've cleaned up a bit, (mild port matching work). This is the HO GTO motor so it has some nice Hipo stuff on it already such as factory windage tray, 7/16" screw in studs, factory guide plates etc. I always wanted something a little different and really can't afford to build a vintage V8 so the Pontiac is the obvious choice. I love the way Alex Idzardis' coupe looked with the 400 in it. My car is really a mid '60's rod and as such the Pontiac fits right in. I'm waiting for my Comp roller cam and valve train to arrive this week so I can move ahead. The new pan and roller rockers are on backorder at the moment. I have the bottom end, rods and pistons together so it's just a matter of parts arriving. I do need a points style distributor yet and I've been working with some guys for the flywheel and clutch I need. I'm using the 3.03 Tremec box discussed in my build thread so this will be a moderate terror to say the least. The old Ponchos were real torque monsters. If they could move a two ton Goat the Vicky should be real interesting.
I think if I was going to run something like that on the street I would treat it like two three duece setups. Idle on the center two carbs and progressively bring in the other ones. Making sure the outers on both sides sealed off at idle. JMO Lippy
I really like 4x2's on the street. I always run all four straight up, plugged power valves on 94's and all idle circuits working. On this one I'd like to run 2GC's as they are a more period correct carb for this car. Working on this car has been making me feel good because I'm almost 70 now and I don't really remember the 50's that much. My fondest memories were the early to mid 1960's. Cars, cruizin, music, it was very different than the earlier stuff. I love the earlier stuff but this one is personal. It will most likely be the last car I build for myself and it will definitley do the job!
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