How does choke length 42mm vs 40mm affect air intake, AFR or anything? I do have F8 e tubes, but why do you suggest to change the e tubes. I have F7 right now recommended by most weber rx7 owners. The car idles perfectly fine with 65F9 idle jet, so no need to touch that. Also I don't want to run the car @ 10:1 AFR. My AFR is around 12.4 right now which is ideal. I may get smaller main say .160 and .140 air to see if it would help me to run the car leaner and help with the emission. I don't believe it will but I may try this regardless.

I do need advice on how to plumb back the air-pump into the exhaust. any pictures anyone?

 

Due to you altitude it may be a signal issue, or maybe not, I've got no experience with a carb that high up hence my suggestion to a larger venturi/choke. With regards to the tubes the engines I put together like them, and I run them on my engine dyno, yours/others may be different. Also the idle circuit has more to do with just the car idling, up to and including its changover to the mains @ 3000ish RPM depending on porting etc.

Last but not least, and I'm sure you know this, I don't do more than one change on a circuit at any given time. I do sometimes swap both idle circuit jets and main circuit jets or airs at the same time if I notice huge issues.

 

Hi rade95

I have a 13b 4port, ported with a weber 48 ida and I do have a f11 emulsion tube but am still testing main jet size and air correction jets. the f7 did not work well so I stayed with the f11.
I do have to say though I do not have a problem with acceleration just drivability between 2600 and 4000 rpm while cruising along flat roads {no load).
Anyhow if You can get the car to Longmont. There is a performance shop with a rotary expert his name is Doug at 5250 performance who may be able to help you.
I'm in Denver so I get the high elevation issues. I also registered my car under vintage collector plates when it had a stock 12a in it so it past inspection. and as long as I reregister it every 5 yrs and keep mileage under 4500 a year it's exempt.

Anyway pm me so we can compare notes

 

Well hello there, so glad to hear from a local RX7 owner. Interesting to hear about your result with F11 e tubes. My car came from WA state and had F11, .200 main and .180 air when I got it. It ran like crap. Way too rich AFR ~ 10:1. I had better results with F7, but I have not tried F11 with smaller main and air jets. Right now I have good AFR, so I want to keep it like that. The issue I have is that this car with 48 dcoe never passed emission in CO, and as fd3 suggested I am looking to install the stock air pump and the cat converter. The problem is the car has gilmer pulleys so there is no room to power the air pump. I would have to tear down gilmer and go back to stock pulleys and belts. Gilmer is useless anyway except for the look and the racing sound. Do you have Doug's phone number and/or the shop address in Longmont. I can get the car there easily. thanks

 

there are two vacuum advance ports on the weber dcoe you have to take off the cover screws and thread in a vacuum take off adapter

 

A picture is worth 1000 words. If you have a picture please post it here.

thanks

 

This whole thread was filled with gold, and a great read. Im about to tackle a Weber 45 DCOE and intake/ RB road race exhaust/ Carter pump and regulator here soon. A lot of this thread has cleared the picture of what needs to be done. Does the vacuum advance need to be hooked up, or can it be skipped?
@rade95 How did everything go from here, what did you end up doing. I wish there was a follow up to see how things went with this! Great thread.