Weber tuning help 13B 6 port
11-01-04, 08:36 PM
#1
FD > FB > FC
Thread Starter
Weber tuning help 13B 6 port
I have a weber 48 MM DCO (no choke) carb on my 86 13B 6 port. I have the ports wired open. My jetting is F11's with 180 mains, 160 air correctors 65f9 idle jets. Do not know the choke size.
The car ran a 15.6 at the track, but I know it can be much faster than that. Its running VERY rich, to the point where my bumper turns black, and I get about 14 MPG. The exhaust is so heavy it makes your eyes water if your standing by the car.
I fooled around with the jetting today, tried some new idle jets, 60F9's. They worked great!! Now I tried puting a 165 main jet in, and it made the top end just DIRT slow. The thing was really struggleing to get to redline in second. I put the 180's back in, and it flies up to redline again like normal, but the idle quality is much better.
Now im stumped ive tried 170 jets before and got similar results as the 165's. What should I do to quicken this thing up? I should be down into the 14's with this setup is there something Im over looking? It runs rich, but when I lean it out, it getts way slower! IM really stumped
The car ran a 15.6 at the track, but I know it can be much faster than that. Its running VERY rich, to the point where my bumper turns black, and I get about 14 MPG. The exhaust is so heavy it makes your eyes water if your standing by the car.
I fooled around with the jetting today, tried some new idle jets, 60F9's. They worked great!! Now I tried puting a 165 main jet in, and it made the top end just DIRT slow. The thing was really struggleing to get to redline in second. I put the 180's back in, and it flies up to redline again like normal, but the idle quality is much better.
Now im stumped ive tried 170 jets before and got similar results as the 165's. What should I do to quicken this thing up? I should be down into the 14's with this setup is there something Im over looking? It runs rich, but when I lean it out, it getts way slower! IM really stumped
11-02-04, 09:36 AM
#2
Racing Rotary Since 1983
iTrader: (6)
this may or may not be of help.... i ran a SCCA GT3 12A bridgeport w a weber downdraft w mandated 38 mm choke tubes. made 259 hp between 7 and 10,000 rpm. my motors were built be roger mandeville and daryl drummond.
170 main gas 110 air corr F7 emulsion tube.
in 6 years i never changed anything but the gas jets and no more than 5 points each direction.
i tuned it by jetting for 1750 degrees on the egt in top gear. egt was 6 inches from port.
good luck,
howard coleman
170 main gas 110 air corr F7 emulsion tube.
in 6 years i never changed anything but the gas jets and no more than 5 points each direction.
i tuned it by jetting for 1750 degrees on the egt in top gear. egt was 6 inches from port.
good luck,
howard coleman
11-10-04, 10:12 AM
#4
Rotary Enthusiast
iTrader: (1)
Join Date: Jul 2004
Location: Rocket City, Alabama
Posts: 1,035
Likes: 0
Received 2 Likes
on
2 Posts
buy an inexpensive, less than $50 air/fuel ratio meter. It will speed up your carb tuning a lot if you know how your mixture is.
If you want to learn more about tuning carbs, then read this article I wrote 4 years ago, if you want to learn which jet affects which part of the rpm/throttle open angle :
http://www.mazspeed.com/carburetorfacts.htm
If you want to learn more about tuning carbs, then read this article I wrote 4 years ago, if you want to learn which jet affects which part of the rpm/throttle open angle :
http://www.mazspeed.com/carburetorfacts.htm
Thread
Thread Starter
Forum
Replies
Last Post
Skeese
Adaptronic Engine Mgmt - AUS
65
03-28-17 03:30 PM
KAL797
Test Area 51
0
08-11-15 03:47 PM
