My dad and I are working on a '34 Ford pickup. We have a '40 flathead V-8 for it. We have Weiand aluminum heads and a Weiand 4-carb intake for it with 4 Stromberg 81's. What would be a good cam choice for this engine? We want something with a good loping idle, but something that isn't too aggresive for the street.
I'm a big fan of the L-100 (search for info) for a lopey idle and good street preformance. 4 carbs, even 81's, would be a bit much for anything outside of an all-out race motor unless a couple of them were dummies.
I agree, the 4 deuces are over the top for the street. If your block is a '40 you probably haven't taken the displacement too big, probably 256? Put some thought into the whole thing-real compression ratio, valve springs, whether to do deck relieving, porting. Yea, they need a lot of porting help to make power. At least a 4" Merc crank. - Just more options to confuse you! Have fun.
Those 4 carb intakes look plenty cool, but I'd run block-off plates on two of them. Even an all out motor will run well on just two carbs.
There was a discussion a week or two ago about 4 2's on a flathead and I think the thoughts was it is fine. I will see if I can find the post or someone may remember it.
It would probably be time well spent to sell the intake on Ebay and replace it with a 2x2 or a 3x2 with progressive linkage. Thats alot of fuel for this motor. I'm running a 265ci merc flathead and 2 holleys gives me all the fuel I need and more. Just my 2 cents.
Good reading on this post about 4 2's. http://www.jalopyjournal.com/forum/showthread.php?t=164109 Vergil
CFM needs change substantially between 180, 360, and IR manifolds. Most flathead 4-carb ones are close to IR configuration, radically upping numbers needed...and not allowing carbs to be blocked. Apples, oranges, hamsters...
Look over the manifold...most I've seen have only small balancing passages between the carbs. They really are just barely manifolds--it's unlikely distribution would work well. Check out that post on four carbs... most are made so pretty much one barrel feeds one cylinder. I know there are other types out there, like the Evans mentioned, but I have not seen those and don't know layout. I've never tried one--but it really seems possible that a 4-carb might be just right for an engine that is over-carbed with three.
The Weiand I have is basically an IR. There are barely anything you could call a balancing passage. Pretty much one barrel feeds one cylinder. I've already looked into the whole 4x2 deal, and I have my mind made up on running this intake. So, does anyone else have any helpful cam information? Is there a cam quality (longer duration, shorter duration, etc.) that is more suited to multi-carb set-ups?
Lemme know if you want to sell the 4-carb intake - I've got a wanted ad in the classifieds section for one. Your '40 engine should be a 221 - so slightly smaller than the more common 239.