calvinpaul

iTrader: (2)

Wow 136@3900....I wonder what it will be at 6.5-7 Mmmmmmmm weber.....

31rx7

My car is stock port 12a. I also have the RB street port header and long dual primary setup.

I will have to look up the specs for the other parts. I don't know the HP output as I have never had it on a dyno.

For kicks at the autocross next spring, I am going to put my race exhaust on which is dual pipes all the way back under the axle to a 3" race muffler. There is a local guy who competes nationally and is a very good driver that I use as benchmark, so it will be interesting to see.

Tom

I had a problem with stumbling at cruise with an early 45 DCOE on my stock 12A. I was told by Rotary Reliability and Racing that this was a common issue with the early dcoe's. I think he said the later ones have some tun-ability with the addition of the air by-pass adjustment, which the earlier dcoe's lacked.

There was a gentleman from the UK that had recommended some bench tuning on the DCOE's to get the stumbling out. It was a trial by error process of drilling small holes in the butterfly valves, and slowly working up in size to eliminate the stumble. He also indicated it was a common issue with the transition circuit (IIRC).

I also know at Rotorfest in NJ this summer I spoke with a guy that had an MG with a 13B SP in the bay. He used a 48 DCOE (brand new) and had the same issue. Great ***** to the walls acceleration but a damn stumble when holding steady cruise at 3,500-4,500 RPM. I don't recall if he screwed around with the air by-pass adjustments though.

The stumble was more than I could bear, since I tend to take my car out for longer road trips, not short blasts. I went back to the 4bbl Nikki.

I'll try to dig up the old thread for you though. Here is what I ran on my 45 when I had it:
F-11 e-tube
60-F9 Idle jet
175 air corrector
180 main jet
85 pump jet

Edit- here's that old thread- https://www.rx7club.com/showthread.p...t=weber+tuners

K-Tune

iTrader: (26)

car was in hurricane ivan and the beautiful trumpets on the weber were covered with rust as well as the linkage being rusted shut.

i'll be fooling with it this weekend...let's hope that carb is still ok

djjjr42

Sorry to bump an old thread but I wanted to comment on this subject. I did a lot of digging here on the forum in anticipation of installing my Weber and gathered lots of facts and ideas. Other people may do the same and look at this old thread and think it's ok to run without a filter, then end up destroying their motor because of misinformation. No offense Robert, you know a ton more about carbs than I ever will, but my experiences today alone showed that an air filter is indeed essential.

I recently purchased and installed a used DCOE 45 with a 1 piece wraparound manifold. During the install process, I noticed some sand on top of my motor, around the little corners and crevices etc. when I was cleaning it up. I have never driven this car on a dirt road or anything like that and I live in the city so IT IS POSSIBLE to draw sand all the way up there. I believe that the metal shield in front of the oil pan is designed with those vents to draw air up into the engine bay, and dirt can tag along with it. Anyway, those freakin' air horns can suck some serious air!! While tuning it up I flooded the carb (needed float adjustment) and used a towel to soak up some of the fuel and then resumed tuning. I revved her up some and whooosh!!, the towel was pulled into one of the horns! It didn't go all the way down of course, but still that's a pretty impressive vacuum! Try putting your palm over one of the air horns while its running and see what happens. Think about it this way, if nothing foreign came in, we'd all have clean engine bays right? To top it all off when I was doing some road testing of my setup, a freaking ambulance came barreling down the street towards me from the opposite direction. The ambulance passed 2 cars through the median (guess they didn't see him as they didn't pull to the right).Just as we are crossing each other this rooster tail of dirt, sand, etc. he created from driving through the median goes all over my car, even in through the window and into my mouth, which was agape from the shock of it all. So I guess there is more than one way to pick up dirt!

trochoid

iTrader: (6)

Velocity stacks are just that, they help create more velocity. In doing so, things get sucked in. If it's in the air, guess where it goes?

680RWHP12A

velocity stacks are on the carb for a reason, just as Trochoid already said, they are there to increase air velocity going into the carb, and they do..
as soon as you interrupt the air flow in front of or around them(air cleaners) the carb does not perform like its designed to... bottom line

a little dirt never hurt any of my cars

i dont remember any of the cobras with 4 IDA webers using air filters, along with all the road racers or drag racers for that matter...

1badFB

iTrader: (1)

Is it true you shouldnt run vac advance with DLIDFIS ?
Did I just miss this little tidbit of info when I did my install? The magnetic pickup is affected by the vac advance right?

FCKing1995

iTrader: (3)

Yeah but what if you live somewhere like I do. During the fall every cedar tree around drops its needles on my car. End up with an inch thick layer, and no doubt some of it ends up in the engine bay as Ive pulled handfuls out. Wouldnt that be bad to get one sucked in? Luckily for me I run a K&N filter on my Mikuni