Technical best bang for the buck

Get what you've already got set up on a dyno. Best thing you can do full stop

 

It has been said that deeper gears in the rear end will give you more "seat of the pants" performance than any other single modification. Another "cheap, or free" modification is to simply lighten the car. One magazine years ago said that instead of looking for a place on your car to remove 1,000 pounds, look for 1,000 places to remove one pound. It is amazing what a difference even eliminating a few hundred pounds makes in how the car performs.


Don

 

You guys are gonna think I'm advertising, but Quickchange.
I know they are not cheap but I got started with them when it came time to put a real rear end in my '56 Corvette drag car. I started looking at Ford 9" and what it would take to build what I needed, spool, gears good case etc.
My problem was that I intended to change engines often and each would likely require a gear change. That could get expensive.
I built my first Frankland for about $300 including resplined 9" axles. For about $35 a set, (used) I can change ratios from mid 2s to high 8s. Put an 8.42 rear gear in and that will be a real 'bang' for your buck. The nice thing is that whatever you do to the rest of the car the rear end gear can be dialed in to give the best 'COMBINATION'.

 

I'd love to put one in my street/strip car....I know guys used to have them in a few drag cars in the 60s, but they have never been very common. Probably because of the disadvantages of the cost, the extra "stuff" that you have to deal with, and the relative fragility in a hard launching vehicle. I have a relatively low buck 9" (stock 57 wagon housing, Moser axles, Strange center, used Ford gears in lots of ratios, used NASCAR locker, modern big bearing pinion support and 1350 yoke) and I put up with lots of my free labor changing ratios.

 

No advertising is when you post a thread about something you got for sale. Annoying to some and offensive to others. Touting a product in a thread that asks a question like this is just saying what you think on the subject.

Unless no one else chimes in no harm no foul my friend. And @5K+ for headers damned cheap results.

I think that you don't see quickies a lot on the strip is as much the fault of the NHRA as it is the rear end itself. You can buy a pretty stout quickchange these days and if you shop you can sometimes find a deal on one used from a dirt track racer turned spectator. By '64 that I know of maybe earlier the quick change had been ruled out in most if not all cl***es on an NHRA track.

I have a 31 spline Ford with a Detriot that I am into for nearly nothing. As in a traded a rear that I salvaged from a parts car that got sold at a profit nearly nothing. But they normally don't go that high around here if you shop around. The local roundy round shop sells rebuild kits for them for around 100 bucks and gears you find where they lay. So if you shop you can be into a stout rear pretty cheap.

That said if I could land a good one I would like a quick change just for the versatility of it.

 

So can you point to where one would radius this intake

 

On this intake your runners look like that have already been radiused but this edge needs to be radiused. Ideally according to current thinking you don't want to have any sharp edges in the intake.

 

Is there a magic radius or just make sure there are no sharp edges.
I took this to a guy with a flow bench. He said he could help it but couldn't tell me how much $$$.

 

I wouldn't remove the septum on a 2x4 intake without dyno testing, as a matter of fact, considering that onces its gone, you cant put it back, I probably wouldn't do it at all on a 2x4 intake. These arrows indicate the areas that I would radius. it would not be that easy, I would use the backside of a 1" ball on the underside of the round holes, and it will require a deft touch.

These are 409 intakes, right? Id be very careful, that's some expensive aluminum you are hacking on. In this case, I would talk to fellow 409 racers first.

 

Yes these are 409 and I have a few to play with.
From what I understand they are not very good intakes but not a bunch of aftermarket for them.
The one that has been modified came to me that way from someone that raced them back in the days but no info on how it works.

Most of the 409 guys that are running hard seam to be closed lip about what they are doing.
Was at the track a few years back with some of them and one had a problem and I was willing to help and he just loaded it on the trailer wouldn't let me help take the carbs off.

 

These otta do it!

 

Nope no majic radius. I would think that if the divider is 1/4 that a 1/8 radius on the top and bottom would do it for example.

Now here is where George and I differ to a point. I have no idea what the engineer was thinking when he designed the intake with the barrels divided on one side and not the other, I would open both sides up the same then cut a power notch between the two sides.

George knows why he is saying what he is saying and it is no doubt sound logic. But that is why were have more then one builder joining in the conversation and he may say something that makes me rethink what I am thinking.

 

Minimum 3/8" radius if you can get it.
As far as opening the septum on multi carb intakes, it pays to keep in mind why this works pretty well across the board on factory single four intakes, 2 main reasons, 1 is increasing the plenum volume and 2 is to gain access to the port entries into the plenum. You have to really think about the "why" when you start grinding, its more important than the "where" or "how".
The "Vanke" mod was successful on late hemis, which led a lot of Mopar guys to think about doing the same thing on the 6 pak intakes. Mopar Muscle did a well do***ented test on this very deal, and on the six pak intakes, opening the septums was an absolute disaster, and they tried a lot of stuff to make it work. They didn't try shear plates, but they weren't really common knowledge at that time. Even with the exhaust gas temps evened out, it was a complete dog, down 20-35 ft lbs across the map. I would approach with extreme caution, especially on a relatively rare intake...
What I would really be interested to try on the 409 intake pictured above would be removing the septums, and trying shear plates under the carbs, but again, I would lean towards wanting to do that on a dyno where I could moniter exhaust gas temps, and I would have to head in with the knowledge that it was an experiment and I might ruin a intake....
The two intakes the op has there look to be functionally pretty similar with the exception of the open septums on the left, why not just dyno (or track test) both intakes...

 

track test both intakes. Based on above, my guess is the open septum works, if the intake was stock under the carbs, or if he had opened the septums and it fell on its ***, he would have been happy to show them to you, and probably would have told you they "worked good"

 

I can fill the factory ones that are still there. So I am guessing to try and match them.

I am sorry if I have derailed this thread.
I got a whole bunch more questions is you want to here them.