Family Software Newsletter #10 - November 15, 2000



1. Holley HP 950 Alcohol Carbs
2. New Quay 4-Link Dragster
3. FREE Software Download
4. REAL World Technical Support
5. New Digital Altimeter

-- Holley HP 950 Alcohol Carbs --

I've been building my own 4150 alcohol carbs for a few years now, and it is refreshing to see that Holley is finally catching up. The HP carbs are pretty good out of the box, but still won't work (at all!) on a drag car without some modification. I've done a few of these carbs for some of my friends, so I thought it was time to purchase one of my own to see if any advances have been made.

First I would like to say again that a mechanical fuel pump is not necessary. Fuel volume is fuel volume, period. A simple flow test will reveal whether your current fuel system is capable of delivering the proper volume of fuel. The best method to test flow, is to take off the fuel bowls and put each one into an empty fuel jug with the hoses still attached. This way you are testing actual fuel flow, through the regulators and needle and seats. Run your fuel pump for 15 seconds and then measure the amount of fuel in both containers. If each container has a half gallon of fuel ( a total of 1 gallon), then your fuel system is adequate, providing that your fuel cell is located in front of the fuel pump. In this location, G-Force will actually help your fuel delivery. In the past, I have used the BG-280 pump, though now I am testing the BG-400 pump.

Holley still ships these carbs with power valves. The only reason I can think of for doing this is that the circle track market is larger. A power valve simply cannot be used in the back bowl of a drag race application. A recent check of the Barry Grant catalog stills shows that BG says that the only way to use a carb with a power valve is to mount the carb sideways on the manifold. Maybe ten years ago, Barry! Simply remove the power valves from both metering blocks and replace them with plugs, Holley part #26-36. You must increase the total jet area accordingly. Holley is using a .120 PVCR (Power Valve Channel Restriction) in these metering blocks, an area of .011310. The carb is shipped with a .144 jet which has an area of .016277. So, the total jet area is .027587 or about a .188 jet size. Holley always jets these carbs rich, so be prepared to lean the thing out quite a bit, but it is better to be safe that sorry. So, plug both power valves an install .188 jets at all four corners to start. You also must have jet extensions in the rear bowl. Holley now ships this carb with a notched float for this purpose. Either use the Holley extended jets or the Moroso extension part# 65441 and use the notched float. I recommend using two (2) bowl extensions to increase the amount of bowl capacity. I use Moroso's, part# 65221 on both bowls. DO NOT install the foam that is packaged with this extension!

Give the secondary idle screw about a half of a turn in more to start. You want to have both throttle plates open about the same amount at idle. If you don't do this, you will end up with the primary throttle plates opened so far, that you will uncover the transfer slot, and the carb will run too lean at idle. You can check this by monitoring your EGT. It should idle around 450 to 550 degrees. If the exhaust temperature is hotter than this, the engine will build too much heat at idle. After you get it running, remove the carb and check the clearance of the primary and secondary throttle plates. If the primary is still open too far, open the secondary a little more and back off of the primary the same amount. That is all there is to it!

I took mine out to test it and it was running out of fuel. A total disassembly showed that somehow, Holley had installed three (3) float springs in the secondary bowl instead of one! No float drop there! So we will have to go back tomorrow night and try it again. I'll keep you informed.

-- New Quay 4-Link Dragster --
Well, we finally bit the bullet and bought a 4-link dragster. Now all the tracks will be ground smooth for sure! Anyway, this is a really nice car. We put a little 433 big block in it and went to Cecil County to test it. I can't understand why everyone says that you can't get a light with a 4-link car. Really! I put .015 in the box and the very first light out of the trailer was a .399! So, we tried it again and went .400. Jeez, lets try it again. So we did and went .398! So we went to Atco and put .020 in the box and out of the trailer went .406. Okay, so you probably think we are leaving at a high RPM. Guess what? Every run was made with a 4800 RPM chip! After looking at the DataMaster computer graphs, we took a stab at a throttle stop factor, set the stop and went 8.880 on the very first throttle stopped run. Killer car!

And now I can say what everyone else has been telling me for years. WHAT BUMPS? That's right, every track is as smooth as glass. This car rides like a Cadillac! I can't say much for the big block. It dropped a valve on the 7th pass! I guess there is a learning curve there. Yesterday, we dropped the small block in the car because they don't eat valves! We'll test the small block combo tomorrow.

-- FREE Software Download --
Our DataMaster Analyzer software, Version 2.0, is available to you as a FREE download on our web site. You don't need a data recorder to test the software and see exactly what a DataMaster Sportsman Computer does better than any other data logger system in the world! If you have any older version of this software, download this as a FREE update.

-- REAL World Technical Support --
With Family Software, you'll get better technical support than anywhere on the planet. Why? Because, I design and program all of Family Software's products and I use them all on my own very competitive Super Comp dragster. All of my 30+ years of experience and knowledge is available to you and our other customers. Try to find that kind of information at any one of our competitors. You won't be able to, I guarantee it! Family Software cares about the racer and his/her success as a racer. The other companies just want your money!

-- New Digital Altimeter/Barometer --
We also have in stock, the best electronic altimeter that I have ever seen. It has a resolution of just one (1) foot. We had previously sold a unit that had a resolution of three (3) feet and we thought that was good! The new unit is just $149.95. You just can't beat that! To read the specs on this unit, just go to the Products page on our web site and click on Digital Altimeter.

-- Secure Ordering --
You can safely order directly from our web site. All of your information is handled on our Secure Server. We have established a privacy policy and it is posted on the web site.

If you have questions or topics that you would like to see covered in this newsletter, please Email them to me. Or, start a new topic on the bulletin board located on our web site. I'll be glad to join in.

Bob Kodadek
SC 1596
Family Software - Drag Racing Computers and Software - 610.497.5561(Voice/Fax)

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