help with bitz racing

[golfbuddah]

I have installed the Bitz conversion and cannot seem to get my idle below 1800 rpm. there are no vacuum leaks, aar is functioning, and all mechanicals seem to be performing properly. new plugs,rotor, cap, wires, timing set, etc,etc. All of the sensors are operational, and wide band o2 sensor is being used. Car runs great but cannot reduce idle. Does anyone have any ideas?
Thanks Frank

[jpnovak]

High idle means you have an air leak somewhere.

Does your idle speed screw work?

What year car? If a later CIS did you remove the vacuum pods and other "stuff" off he back of the engine. Two of these lines feed in below the throttle plate and could indicate an air leak if not properly plugged.

Other possible places.
injector to bung (o-ring)
injector bung adapter to runner (o-ring)
runner to head (gasket)
runner to airbox (rubber sleeve)
Vacuum connection to airbox (various hoses)
vacuum connection to distributor

unseated pop-off valve.

Hope you find it.

[golfbuddah]

I have used carb cleaner and sprayed virtually connection where there could be a leak. No leaks detected. I will check the distributer and recheck everything else tonight. I assume the idle speed screw works, turn it all the way in and it kills the engine. I have converted from carbs so I did not have any cis stuff to remove. I bought the intake that was already converted to clean look for bitz conversion. Car has a 73.5 2.4 liter.

[jpnovak]

What intake do you have? Early CIS?

Some carb cleaners are not flammable. This is not always the best method to find a leak.

If the idle screw works to shut the engine off, then just turn it down until the idle is about 800 or wherever stable.

Otherwise, Use the vaccum port and pressurize the intake with an air compressor set to about 40psi and listen for the air leaks.

[Joe Bob]

I use ether aka kwik start....some use propane.

[cmonref]

Otherwise, Use the vaccum port and pressurize the intake with an air compressor set to about 40psi and listen for the air leaks.

... watch out for one cylinder's valves at overlap.

[Scott R]

Linkage set incorrectly, distributor hung up internally maybe.

[jpnovak]

Originally Posted by Scott R

Linkage set incorrectly.

Since you did switch intakes this is a real possibility. Does the idle drop if you disconnect the linkage rod from the bell crank or TB?

[golfbuddah]

I checked for leaks with compressed air. No leaks found. I believe the linkage is set properly. distributer advance is working. No change in idle if linkage is disconnected from throttle body. Intake is from 3 liter with 38mm openings. I am also noticing that the fuel pressure drops to 20lbs when cranking is this normal?

[byfdinky]

Good Luck! I still have not been able to get my Bitz kit tuned!

[Scott R]

Couple of things guys, when I installed my BITZ I had no idea what was wrong with my CIS system. In reality probably nothing was wrong, but just about everything else was. If you're having trouble tuning it's a good (imo) to take a careful look at the other systems. Ignition for starters, the fuel system, condition of the engine internally, etc.

Also make sure you join the Bitz yahoo group, you can post all of your issues to the list and it's very active with a lot of knowledgeable people.

[golfbuddah]

I will try the Bitz forum for help

[golfbuddah]

Ok so the saga goes on. new airbox installed no leaks as confirmed by smoke test. ECU and manual vacuum tester show no vacuum at clean and open port on throttle body below the butterfly. There is plenty of suction on the top of throttle body. If we take the vacuum tester and hook to the ecu line it will respond. Car running no vacuum!!!!
My mechanic feels I have a cam timing issue whereby not enough vacuum is being created using one t.b. to feed six intakes. Car ran ok with carbs because each cylinder has a dedicated downdraft situation. We are also having an issue with timing. He is well respected and says it is all related. Any thoughts before I return to carbs? Thanks Frank

[brads911sc]

what cam are you running?

[golfbuddah]

I do not know. I bought the car used and have not had the motor apart.

[brads911sc]

I have a set of SC cams ill sell you if you want them. If you really want to run Bitz, you need a mild cam...

Originally Posted by golfbuddah

I do not know. I bought the car used and have not had the motor apart.