DuffyMahoney Posted September 3 Share Posted September 3 How close are they synced now? Are you removing linkage to do that? Are dog bones the exact same lenght? Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 3 Author Share Posted September 3 1 hour ago, DuffyMahoney said: How close are they synced now? Are you removing linkage to do that? Are dog bones the exact same lenght? I’m using cable control on the linkage. So the issue with them is the cascading effect of using cable on one ITB that has direct linkage to the other two . It causes #1 ITB to open up sooner no matter how I try to adjust . I also have #4 port that doesn’t flow as much air as the rest . Maybe a butterfly issue - slightly off. I would go with rod linkage but I’m pushing it for time to make it to ZCON . I’ve tried syncing the best I can at lower TPS by just holding throttle open with cable adjustment and calibrating 3-6 . Once I’m around 12+ TPS - AFRS blend much better . As far as #4 - I will address this with injection trim . It’s just light cruise where I have to pull some fuel . I’d love to try the rod linkage but I’ll have to see how much time I have . It won’t help with the center ITB . I’ll have to take it off and see about doing something with the throttle plate . Again - it much time for that right now Quote Link to comment Share on other sites More sharing options...
DuffyMahoney Posted September 4 Share Posted September 4 Linkage is what I am calling the small arms between throttle bodies and the shafts. You need to remove everything connecting each throttle to the overhead bar. Then sync. Then check again once hot. Also blip each throttle, see if they stick or bind once hot. You should have the cable going to a cam on the overhead bar. If that isn't what you are doing, I would highly suggest that route. Setting butterflys is extremely difficult to do perfectly. I would print the 3D file I posted for syncing, then set each off the car. Then put each in an oven to 185 and check each again. Do you have an injector company in your town? Have them checked for flow matching? Quote Link to comment Share on other sites More sharing options...
DuffyMahoney Posted September 4 Share Posted September 4 I really think you should move to an overhead bar. Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 7 Author Share Posted September 7 On 9/4/2025 at 12:03 PM, DuffyMahoney said: I really think you should move to an overhead bar. I will do this -eventually. I did pull the center ITB and tested the flow past the butterfly using a vacuum cleaner . Not sure thats an appropriate testing method but the sync tool showed same flow between the two ports. So maybe my issue with 4 is a porting of that intake runner at low flow. At this point I did another valve adjustment -cold- and I did end up finding small adjustments needed, so we will see if that changes anything. Meanwhile I am going to use injector trim to even things up the best I can before Zcon. Quote Link to comment Share on other sites More sharing options...
madkaw Posted September 22 Author Share Posted September 22 So after doing a valve adjustment my ITBS did sync up better . I guess I will have to keep an eye on that. I took out most of the injector trims and my afrs between the banks paired up better -especially at light cruise . I also worked out linkage issues I was having. You get no instructions with this kit and there was adjustments that I could have done better like the main rod-the only rod-to bellcrank. I didnt have it pulling the linkage in a straight line. Also found the linkage on the side of the ITB loose . This caused the linkage to rub against the body of the ITB. I got all this sorted right before ZCON . It was 4.5 hours to Nashville on smooth highway. 80 mph is where she likes to cruise . AFR's were around 15 on flat ground. No issues on the round trip. Got some great compliments from Peter Brock on my airbox . Cold idle is still 650rpm and about 800rpm when hot . AFRs at idle are normally around 13.1 Now to move on to IAC . I gave up on it right before I left . 2 Quote Link to comment Share on other sites More sharing options...
madkaw Posted 9 hours ago Author Share Posted 9 hours ago The vacuum log from has reappeared ! I added back the lines I took off before ZCON. 2 x .250 lines merging into a 3/8 line to a remote stepper valve . Kind of got it working today . The biggest must is to have it close all the way . You can’t afford to loose any vacuum with the ITBS . Quote Link to comment Share on other sites More sharing options...
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