Rotary Revolution

Alright, spring break starts tommorow for me. Now I plan on doing this mod tommorow. How much will this actually benefit me. About how much faster and so on, and how much it will take off you 1/4 mile time?

karism

Its basiclly impossible to say,seeing that altitude differs,you setup(exhaust,mileage,driving style,etc)

I suggest that you do the acellerator pump mod that Sterling posted as well, i found it to make a nice difference.
You can do as search for "carb crap" or his username Sterling

djmickyg

i never got 2 drive my car b4 i did the mechanical 2nd's but everyone thats done it swears by it.. it just gives u full controll of the carbby. instead if the the 2nds opening up graduallly as the the rmp rises from about 3000. u can plant the foot down and have it all fully open. but it takes a bit of getting used to no flat footing the car on take off.

whats this fule pump mod? i remeber reading it ages ago, but i cant remeber it. anyone got a link to the page that expains it?
thanks

esoto66

Go here http://slegers.com/sites/sean/

Sterling

It's not a fuel pump mod, it's an accelerator pump mod. It give a bigger squirt of fuel when you first put the pedal down.
First make sure you understand the purpose of the accelerator pump. Then you'll better understand how the mod will help you. It not only increases the volume of the accelerator pump, but also increases the stroke at which it pumps.
The stock set-up stops squirting about the same time the secondaries are allowed to open. If you switch to mech seconds, you'll see that the squirt stops about the same time that they open. THAT'S NO GOOD!
So the AP mod was really just to extend the squirt so it kept a stream of fuel squirting throughout the opening of the secondaries.
The I had to add some gaskets to increase the amount of fuel so that it delivered the same size squirt (or slightly more ) throughout the longer stroke.

It's neat, It's cheap, It's simple, It's reversable, It works, and It's fun as hell!
But it won';t do anything for you but use up fuel if you don't convert to mechanical secondaries first!

My artical is alot of reading, but some things are very important, such as making sure all the butterflies are standing exactly straight up and down at wide open throttle.
Someday I'll rewrite it and provide accompanying pictures.
My advice is to read every modding artical you can find, and you'll begin to easily understand every one of them. Mine's a PITA because you can get lost in my descriptions, and then the rest won't make sense.

Just read it through and see.

The carb is a precision metering device. Attention to itty-bitty detail is a MUST!!!

djmickyg

i understand the purpose of this and i'll be taking my carb of soon, so it will be a good chance for me to give it a go..
how think was the gaskit paper u used??

p.s. nice write up u had on it sterling, very informative.

Sterling

It was just some generic material. All completed, you want to add about 1.5 - 2 mm of thickness on each side of the diaphragm.
Too little added and the volume won't be increased enough; Too much, and you risk tearing the pump diaphragm.

Rotary Revolution

Alright, I have completed this mod today. But it seems that at full throttle, the secondaries only open half way. Is this normal, or is there a way I can make them open all the way?

Sterling

Did you look at the pictures on 82transams site? (The site in the second post)