Hey Everyone, after going through a few motors, I finally have one that works. I built a 13B 4 port Streetported with turbo 2 rotors and a T4 turbo, etc. I have a Webber 48mm Sidedraft setup on it but cannot find the right combination idle jets, main jets, emulsion tubes, air correctors, etc. The car backfires, doesn't run too good etc. The car runs decent pretty much only under boost. Everything else is set right: timing, plugs, etc. If anyone has any advice or any knowledge as to what size components I need for my carb/setup please let me know, I want this motor to last as it pulls hard and has an awesome amount of potential. Any help would make me happy as hell.

 

So your running a turbo weber setup?


The car runs fine under boost, but idles like ****?

I think the jets are too large, what size are you running now?

 

is it too rich? too lean? there is a narrow air/fuel band where the engine will be happy at any given time, if you are off either way its wont run well

mike

 

Mike, to your question, the motor runs lean at like 1/4 to half throttle or so and backfires, pops, just runs shitty, then richens up under boost. Either the car is happy idling or under boost, no happy in between and it really sucks!

 

you should go and buy a weber book, its actually not that complex once you know what each part does (i'm reading one now, actually), i was also going to ask what kinda of fuel pump and pressure you are running? its important for carbs to have the right pressure

mike

 

You might try talking to 'Pierce Manifolds', in Gilroy CA.
And if you can find the number, a place called DMD in Daly City or So. San Francisco (forget which).

 

I am running a Jay-Tech manifold with a Holley 650 and it is very hard to tune it with a rotary turbo, it has to be perfect. Your best bet is to find someone with a dyno so you can just put the car on it and keep changing jets until it is right. I have'nt worked with a weber setup yet but I chat with a gut regularlly down in Florida that knows a hell of a lot about turbo-rotary-carb setups.
revpower@newave.net.au That is his email. Great guy! Ask him anything. Ohh yeah, My car runs just like yours, great idle but 1/4 throttle it leans out then great under boost but I'm pushing over 20lbs. so it leans out at about 15lbs. I am still in the process of going up jet sizes until I get it right. Keep going though because everyone I talk to says that if you want the most from your 7, carburete it!