rototiller1

Anyone care to try it first? I built an adapter to go from the stock 12a manifold to a carter afb, I was given a 625 cfm afb. No clue on how to jet it, but it is similar to how the nikki works. I would hope that its better than a holley. Should not have any problems going through corners or hard launches at the strip.

rototiller1

No one has a clue? is this uncharted territory

rototiller1

Ok, I built it I will test it.

813KR$

Do Carter's have the same bolt pattern as the Holley's? Will they fit on RB Holley intake?

rototiller1

yes they have the same pattern

813KR$

How much do you know about Carter's?

How tunable are they?

Do they have adjustable air bleeds?

Are they a stock carb or is it a company like Holley but not as popular?

I dont know much about carbs, but trying to learn as much as possible! Iam learning alot about my Holley, since I have had it. The Holley's are not very tunable, jets, float level, fuel pressure and idle air/fuel mix is about as much as you can play with. Unless you want to take it off the engine and start grinding **** or their might be something I dont know about yet.

Iam sure if the adapter is quality and works well you could probably sell them, as long as you can make them affordable to make it worth your time! I see people wanting them and using crap adapters.

rototiller1

http://www.carcraft.com/techarticles/1071/
This is the tuning procedures

rototiller1

wellthe carb is at the shop being hot tanked

rxtasy3

iTrader: (2)

Very interesting reading, thanx. Would like to try one of there 600 cfm carbs.

813KR$

Rxtasy: You aim is nosrx4, you run nitrous?

rxtasy3

iTrader: (2)

Nah, I have it, it's just not on the car. When I created that name I had an rx4. My Yahoo ID is the same but is a 3 instead of 4.

rototiller1

For those who want to know my progress, The adapter fits but its too tall, So I have to make another one , 1/2
an inch shorter.

Maxthe7man

They sell a spring loaded float kit for the edelbrock that will work in the carter to cure fuel slosh on launches, the edelbrock 625 is the same as the carter with a few minor upgrades to make tuning a bit easier, you can buy the edelbrock strip kit and it will work..
I used these carbs for years on mopar v-8's, the important thing with them is to run a phenolic intake spacer to stop the carb from getting to hot, being aluminium the transfer alot of heat and will boil dry when parked and stink the car up with gas smell...Max

813KR$

ever get the adapter done? Iam looking into getting a modded nikki and want to still use my RB intake. You said, you got one done but was too tall. How tall is it? I may be interested in it or if you have made a better one may be interested in one of them? Let me know the deminsions and how much you want for one and I may purchase one from you?

rototiller1

Well I welded a open plenum adapter to the stock manifold and blended the the bores to the spacer.

Got the carb jetted , It works great.

pri. jets .095
sec. jets .092
metering rods Pn# 1448
orange springs
pump lever in the first hole from the pivot point
and drilled 3 1/4in.. holes in the secondary air valve counter weights (each side)
edelbrock 1/2 in. heat disapation plate

I like it, much better than the nikki

rototiller1

Driving it today I noticed a slight surge during cruise, in 3 gear and in overdrive, so will need to change the metering rods to #1445's. Its is just alittle lean in cruise.

These setting are at sea level, the engine is 12a and not ported, YET!

rototiller1

put in the 1445 metering rods and the pink springs, much better, now going to remove the secondary air valve

rototiller1

Ok, this setup really pulls great in 1st, 2nd gear, to 8000+ rpm's; but in third gear it goes flat at 6000, with wide open throttle. So what do ya think? Do I need to richen up the secondary jets?

Remember this is an automatic, it may have to be converted to a manual

Or its time to add a turbo, or nitrous

rototiller1

I'm trying 1 step richer on the secondary's

rototiller1

So this is the final, to use a 625 cfm AFB on a stock port 12a at sea level and 70 degrees air temp.

.095 primary, .101 secondary, #1445 metering rods with the pink springs, and remove the secondary air valve.

If you can't mod your manifold to fit the AFB, the racing beat 4 barrel manifold, should work the same, probally better.

Next, I'll add a wet nitrous.

rototiller1

WOW! 17.7 MPG, the nikki only got me 10.

If I could find a reverse flow manifold to mod, it could only get better

Rx7carl

Did you ever fix this problem? Sounds like your running out of fuel. What fuel pump are you using?

Rx7carl

Mine (Nikki) gets me 20mpg and its an auto also.

Im not so sure a reverse manifold is a great idea. I thought so at one time till I flowed the iron plates on the flowbench. The primaries are teh sux0r for flow. They wont support the secondaries flow needs.

rototiller1

I went from .095 to .104 on the secondarys and its alot better, may go one more size up. If I back off the gas just a little bit from wide open I can feel it pull, wide open it just starts to go flat.

The gas milage is better than what I was getting, with my lead foot.

My pump ie a holley blue, with regulator set to 6 1/2 lbs.

The engine has 196,524 miles on it