I've been thinking about building a log manifold setup for my 324ci olds rocket engine and need any advice you guys have. I like the looks of the 6x2, but I'm thinking of going a little "out of the box" traditional. I want to use another rochester 4GC like the one thats on it. 2 log manifolds, 1 4GC for each bank. Does anyone know the CFM of the 4GC? Is there any major pitfalls to overcome when building your own log manifolds? I'm sure I can handle the fabbing of the manifolds, just don't want to have **** that won't run when I'm done! I need info please! Later- John
Considering the number of logs that have been in use, they must work. And considering the engine runs well on 1, and lots of 3-2s around, 2 2s should be fine.
I'm running a crower-u-fab on my yblock in my A coupe with 4 94's, was a ***** to get set up but works really good now, only real problem is i'll fowl the back two plugs on the drivers side after about 500 miles , could fix it by jetting down the one back carb but besides that it gets about 16 miles per gal on the road.
Yeah, I was thinking two 4 barrel 4GC's side by side. So to home build one I just build it and tune the bugs out? I read a writeup on sheetmetal manifolds and it was talking about plenum volume and runner length and pressure pulses and I was getting discouraged. I'm not building a race car, just want her to fire and run up to 4500rpm or so. Oh yeah, and the number one reason, look cool! Maybe someday someone with the know-how will do a tech sticky on the subject. Hey, it might be me! "How to build an OK log" by John....hmmmmm..... Later -John
Potential problems: the plenum diameter has to be pretty big to accommodate that bolt pattern, much larger than the usual 3-4" OD tube. If the volume of each log isn't big enough the ends cyls will be lean. I don't know if the carbs should be in conventional position (primary ahead), or rotated 90° (primaries facing each other), which may provide better distribution. You have a chance here to make a cross-ram by simply mounting the logs on the opposite side and crossing the runners. You can have long tuned length and still fit under a hood. If you make the runners flanged to the plenum bottom you can port them from inside, and take the plenums off to work on the valves. More: http://victorylibrary.com/mopar/log.htm
I never thought about a cross ram, that sounds cool! I think the ports are paralelle to each other though, the runners would have to take evasive action, but it's doable. I'll check out that link, maybe that will shed some light... Thanks- John
Just a quick reference http://victorylibrary.com/mopar/log-c.htm *edit* oops, someone above me got the same link, sorry!
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