Im putting together a turbo kit for the 12a using a weber 40 idf. I figure it should be good since there is a guy here running the same carb on a 13b.

My question is while im getting the turbo together will I be able to use the weber 40 on the car in a N/A setup. I have a stock port at this time. Im thinking it will be ok to run for a couple months till I get the turbo situated.

thoughts????

Sean

 

it will be juuuussssst fine.

 

Yeah it should work good with the right jetting. What size turbo did you have in mind for your setup?

 

40 idf? what's the biggest choke that carb can use, 36mm? 36 is small. won't get the max performance out of that turbo with small chokes, but it would make decent torque. I bet when it revs to 7000rpms it'll be like hitting a wall. Max flow of carb reached.

 

Its a KKK K26 turbo, I have a japanese OPTION 2 magazine with its newer version in it. Say it will support 500 hp. I think they where mainly used on porshes and audi's. Its pretty big when compared to the intake manifold. I just have alot of stuff to get together before I can install.

look here if you want to see pics



previous forum post

DriveFast7--
on that max flow of the carb that would probably relate While im running N/A. but once I put the turbo on and start force feeding it. I dont think 7k will be a problem.


FBII-- Just wanted to say thanks you have been really helpfull with most of my questions.

 

Just trying to help out. You can only get so much air and fuel through a carb regardless if it's force fed or not. Most people put BIGGER carb on when the go turbo because turbo forces more air in and the carb needs to be big enough to allow that air to flow thru at an effecient rate.. AND be able to supply enough fuel to keep up with the air flow.

Small chokes in a small carb are a bottlneck. Like blowing into a straw with a plug in the middle of it that has a hole in the center. ...

I ran 37mm chokes on a 12a streetport with a high flow exhaust and at 7k the motor stopped making power because the carb reached it's peak effeciency. Revving it any higher was just spinning the motor, didn't make any more power. Switched to 39mm's and she made power to 8k+.

I've personally seen a KKT turbo kit for a 12a rotary and it came with a Weber 48 IDA, which can support chokes up to 44mm.

FYI IDA flows more than IDF.

Saw those pics, that is a neat little kit. Intercooler is a nice compact size. Let us know how it goes? Do you have any baseline jetting for the carb with this turbo kit?

 

Thanks for the heads up. didnt mean to dought you, just head different info.

No base line, pretty much learning as I go. I saw a post on another individuals set up was planning on starting from there

 

I've noticed in the past few months or so, people trying to squeak by with the 40mm carbs. Is it that there cheaper or are people just not willing to put down the cash for a 48?

 

Well, from what I have read I dont need to go to a 48 with my setup at this time. but yeah i did get the 40 due to the price. Im tring to get 200 rwhp for under a 1000.00. Right know im at 570.00 with the price of the car. but I still need to get a fuel pump, RRFPR, and Exhaust made.

 

Any carb WILL flow more air under boost than it would n/a. That's why draw-through style turbo systems need far bigger carbs than blow-through to make the same sort of power. I doubt 40mm will be big enough though.

 

This guy is running a 40idf on his 13b is think he said that it is making 186 rwhp @7000 rpm untuned. Im running a 12a smaller engine so I believe my 40 will work just fine.



pillage6 words of wisdom

 

yea, just get it up and running and then for sure you will see if it's enough, it's not hard going up to a bigger carb, just a matter of a little $$$. hahaha, oh and your welcome for any info i can give you. i think i've dipped out on my 12at project, maybe, but i think now i'm going with a fuel injected 13bT setup.

 

My car runs fine with the 40IDF, but I don't boost over 12 lbs.

My jets:

Idle: 50
Main: 210
Air: 140
Choke: 32mm

These are all off of my memory, which has been pretty fuzzy lately, so don't quote me on these numbers. My Autometer A/F meter reads 3-4 lines into the green at all times, even at idle.

I have a stock ported block and a bad exhaust leak.

 

pillage6-

You have any problems at any RPM range. Will the engine redline without a problem?

 

how much power does it make with the 32mm chokes? if no dyno sheet available, what cars do drag race and win?

 

Why do you have to be an a$$ on that?? and my guess on what cars would not be yours!!


I appriciated you opinion on the subject of the post. But not on how you remarked on the guy.

Its not a "KKT" kit its a Sigma kit with a KKK turbo. It could have been a typo but the "k" and the "T" are not exactly next to each other on the keyboard.

The guy has helped me out. He's is running a nice set up on his car. I do believe he has a dyno sheet available at 180 something that he hasnt tuned yet. The point of this post was to be if I could run a 40 idf carb on my car N/A till I have the turbo setup finished. you say I cant without problems, other say I can. In about three weeks when I get back from Japan I will put it together and tell you how it runs N/A. If I hit a 7000 RPM brick wall or go drag racing with a 1000.00 price tag on the whole car.

 

When I dynoed last at 8 lbs., exhaust leak, heavy flywheel, no rotary pak, old plugs, not so good fuel pump.....etc., etc. I pulled 182@6800rpms.

Why did I peak at such a low rpm? I don't know. I have not gone to the dyno since then after installing all the stuff in my signature and turning up the boost. I am figuring (hoping) somewhere in the 230-240 range.

I have not really run anyone except my friend's S2000, which I walk away from. I don't get hit up to race at all, which is funny since my friend borrowed my car one day and got hit up 3 times in an hour to run.