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-   -   13b bridgeport carb? (https://www.rx7club.com/new-member-rx-7-technical-256/13b-bridgeport-carb-1042252/)

shaunfus123 07-31-13 01:20 PM

13b bridgeport carb?
 
I'm brand new to the site today so thank everyone for any input.
I have an 85 gsl 13b bridgeport that ive had some trouble tuning. When i bought the car about a year ago, I was told it had a 600 cfm holley vacuum secondary which ive learned is retarded to have a vac second on a manual. My problem is i cant get the idle mixture right and when i get up to high rpm, it wont get past 6000 without "redlining" when i should be able to get to 8. also the throttle response is very slow. whenever i shift i have to ease on to the gas to build rpm before i can get a solid shift. I have adjusted the float levels and hooked up a vacuum and the highest read i get is 14-16 psi because it has a rough idle(bridgeport). Reccently, i installed an aeromotive billet fuel pump and also a regulator at 5 psi which i was told is ideal for holleys; the jet size is 25 also. I've seen that the right carb for a 13b bridgeport is about a 650 cfm mechanical secondary but i don't know if the 50 cfm difference would make so much of a problem. Any help is greatly appreciated. Thank you.

diabolical1 08-01-13 11:36 AM

welcome to the board. :)

1. is it a regular Holley or an RB-modified Holley?
2. what is the volume output of that Aeromotive pump?
3. have you tried running higher than 5 pounds?
4. what's your exhaust setup?

shaunfus123 08-02-13 09:44 PM

Thank you!

I'm not sure about the carb. The pump pushes 14 psi and I've tried running it as high as 8. I did notice the nozzle size is 25 so I dropped it to 5 psi. I was driving home yesterday and my car just cut off at a light. luckily I was right around the corner from my house so it started and made it there but now it wont start. The fuel pump still works but its not getting power and when I went to check the relay, there was none. When i originally installed the pump, I was told I wouldn't have to rewire it. Is this true or could that be the cause of the lack of full power band as well?
Thank you

shaunfus123 08-02-13 09:47 PM

...and if i do have to rewire it, do I need to run a relay or just a 10 guage power wire with a fuse between the battery and pump and ground it out?

ArmyOfOne 08-02-13 09:59 PM

Run 10 Gauge wire to a relay and use the stock pump power wire to control the relay.

It should have a 29-31 pump squirter, you might need to mess with the air bleeds to get your transitions right. The vacuum secondary might work but you will need to replace the canister with one that has an easily replaceable spring.

Fuel pressure should be about 6 1/2 psi if you are running dead head, if return style then 6 should be fine. Set timing between 25-28 BTDC 0 split. That will bet you in the right area.

Main problem wit vac secondary setups is that it uses a metering plate instead of jets on the secondary side, pain in the butt to deal with but it should be simple enough to figure out.

If it will not start check the regular spots, spark, plugs and rotor and cap.


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