But, I've to ask these three questions:

How would an ECZ-B manifold (which I assume is an upgrade from stock) compare performance and/or feature wise to a Blue Thunder?

Is a Blue Thunder any taller than a stock or ECZ-B manifold... air cleaner clearance a concern?

Is a heat spacer really necessary as a prophylactic to perculation or is it an aid to atomization?

Cheers fellas, and thanks for such a great site... Brian

Carb pad height is about 3/16" higher than stock. 54-56 cars and all trucks have no hood clearance problems. T-Birds are close and won't allow much in the way of spacers

While a certain amount of heat in the intake manifold is good too much is not good. Heat in the intake tract will help the fuel remain atomized as opposed to liquid, this is desirable. Heat insulating carb spacers can be benificial,and most guys use them where space allows.

I have graphs of stock vs Blue Thunder dyno tests but can't post Power Point presentation.

I’ll add that the ECZ-B intake isn’t modern carb friendly from a carb bore perspective.  The sizing of the bores in the ‘B’ intake are smaller than that of many of the newer carbs and will require either a spacer or the bores in the intake itself appropriately enlarged so that the carb can open freely or without restriction.  The new John Mummert intake and the Blue Thunder intake both take the modern carbs without issue.

I’m not far from doing a serious intake manifold test on the 312 dyno mule and that should prove to be interesting.  I have a multitude of modified ‘B’ intakes but in looking around, I have no dead stock ones laying around so I’m looking for one of those now.  I’m pondering exactly what carbs and spacers to test on these manifolds and that simply adds to the complexity of the test.  Would like to borrow a factory Ford 1.08” flat top carb to add to the number of carbs being tested if someone has a good one.

Richard

If you don't find one close to you, I have a stock B manifold you can borrow.

Jan (Cactus).  I came across both a 1.08 and 1.12 4V Ford carbs yesterday and because they are local, I’ll have them today or tomorrow.  This will save shipping stuff around the country at least for now.  If the 1.08 carb I get doesn’t pan out, then I may give a shout back in regards to yours.

John (Hoosier).  Glen has offered up an intake that will fit the bill, but I also have a ’57 Fairlane sitting in the shed that I can pull the intake off of and use.  But I’ll keep yours in mind if all else fails.  I had several stock intakes about a year ago but there was an unexpected demand for them and now they’re gone.

Glen.  Hold off on the intake in the short term as there is one on the ’57 that I can use and another may show up locally anyhow.  I may still be interested in the 1.08 carb you have if the one I get doesn’t work well.

The plan is to do the intake manifold testing mid to late December.  That will give me enough time to get all the parts lined up and ready to go.  I still need to kit my ’57 Carter carb and make sure both Ford carbs I plan on using are in good shape.  The other carbs I have on hand are already in good condition.

As far as carbs go, I already have the ’57 4V Carter, the ’57 ECZ 4V Holley (model 4150), several L-1850 600 cfm Holleys (model 4160’s), a 750 HP Holley (model 4150), and a 650 cfm Demon.  For the stock intake test, I’ll likely also pull the 525 cfm Road Demon off my ’55 and test it along with the other carbs.

The plan is to first test with the stock manifold with the factory ½” phenolic spacer and the three factory carbs that came on the 312’s in 1957.  I was always led to believe that the Carter carb would outperform the Holley and Ford carburetor equipped engines.  Beyond that, I’ll test some different spacers and the other carbs before pulling the stock intake manifold and switching to the other intakes.  I have a factory 2X4 setup with Teapots that is also itching to be run.  Also currently not being used and I can get back to me is a very nice running 3X2 setup with Stromberg 97’s that performed flawlessly on another engine that was recently dyno tested.  With the Mummert intake or the Blue Thunder, I may try the 1050 cfm Holley just for grins.  It actually worked well on the EMC engine but didn’t have time to work out a carb spacer that fit the EMC rules.  I doubt that the +060 over 312 is going to like being loaded up with the Dominator carb but I don’t see any idling problems with it, just a problem in throwing the throttles wide open and holding them there at 2500 rpms.  Wait and see on that one.

On the EMC engine, I actually tested 6 intake manifolds in a 4½ hour time span so if everything is laid out in advance, I should get some resonably accurate results over a short span of testing.  The number of carbs and spacers being tested will also be consideration timewise and I may end up testing only 2 or 3 carbs on each additional intake along with a given number of spacer variations.  Part of this will likely depend on how much help is available when I actually do the testing.  There are times when walk in help actually slows the process down.

I also came across a pair of model 4010 Holleys with one being a 600cfm and the other being a 750.  I’ll look into kits for these and running both of these on the dyno mule engine.  The model 4010 Holleys are now being sold under the Summit label and are designed very similarly to the older Ford flattop carbs.

I came across this dyno comparision of the BT intake versus the ECZ-B intake on the WebRodder site.

http://www.webrodder.com/article.php?AID=175&SID=60