Street tuning downdraft weber
 

Ok im going with an 48 IDA Weber set up in the very near future and it will be tuned properly no matter what (whether i do it or i pay someone) but i want to have some flexability with the carb....In other words, which array of jets and other items such as phenolic spacers should i buy for the street. I want to be able to decide what would be best for my driving habits so list out what would be the best components to buy....dont say just get everything you can cause all these little pieces i have found to be pretty expensive for what they are.....this is for a stockport 12a with pretty clear exhaust and slightly upgraded ignition(msd 6a might be down the line)

spacers? if you use it, the air cleaner will hit the hood. A common issue with 1st geners using IDA. Without it is fine.

Venturies=40-42
Idle jets= 65-75
Main=190+
Air jet=150

Must:
Progression holes=3 holes max
Throttle linkage= top or bottom pull
Gas cable bracket
Open mind and lots of heines

PS:
Since you're in Las Vegas, 95+ heat will kill any aftermarket carb wether its a weber, dellorto, holley, etc etc.

man, why are u even bothering with an ida on a stock port with stock exhaust ?

its like trying to stuff a 100m sprinter with loads of air and lucuzade at the same time but he's got small nostrils and small lungs...it just won't work. He'll choke and splutter.

moral of the story ; the 48 ida is part of the bigger picture. You need bigger ports, both intakes and exhaust, and u need the exhaust system.

re the spacers...from what i've heard, they vary the torque range on bridge ports.

He has plan...a very good plan. Something I hardly see nowadays.

thanks for the info dude....anyways, i have headers free flow cat and rb muffler! ; ) prob. getting rid of muffler for more straight thru one soon too....why not do this? sounds great to me, i will learn a lot and have fun.....street porting will come down the road when i blow my motor to kingdom come.............

I'm in the process of tuning now, and i'm running a RB streetport 39 venturies, 70 idle, 190 main and 150 air, and its still running really rich. a small pile of ash collects behind the exhaust when idling. great carbs tho, they sound SOOOOOO good. i just bought a wideband, and it should really help dialing everything in. and spacers will not let the air filter fit under the hood, unless you cut a hole in the hood. Good luck, and Great choice, they are by far the most tunable carb, don't let anyone tell you different, they are just jelous!

39??? thats way too small. On a streetport, I use 42 or 43 but for my own cars, 45 for cruising around town and NONE on the track.

Hey wacky, good call, maybe i'll pick up some bigger chokes, I hav ea problem, tho, that at part throttle at cruising speeds i get alot of jerking and jumping, are these carbs cold blooded in that respect or does it just take tuning?

Smaller jets wil help your cruising speed. How many progression holes do you have? rotaries love 3 progression holes per barrel. With main and air, I usually go with a difference of at least 50 increments (ie., 150 air / 210 main) to make it rich on top end.