Rochester 2 jet tripower problems.

This is what I used. It works. Someone called it a bandaid earlier in this thread. Whatever. The shit works.

http://www.pontiactripower.com/shop/throttleblade-sealer-dag

 

Thanks for that imfo. F-6 all of the advice in your previous posts have really helped me get my problem of bog just off idle much better. That SOB will really turn on now thanks again. By the way I also like the truck f''in cool.

 

Thanks man. Hope your tripower is runnin better.

 

Bringing this back up. Ulu, what methods have you used to plug and re-drill the transfer ports? I finally got my tri power running. Just the center carb for now. Had to drill some holes in the throttle plates to get the idle tamed down. Reduced the diameter of the idle tubes to get the mixture screws in the 1.5 turns out range, but no amount of air bleed or idle tube adjustment has cured an off idle dive into a pretty rich condition.
Keep in mind, this is just observation of an air fuel meter as the throttle is lightly opened off idle, under no load (car is not driving yet). I have 17”-18” of vacuum at idle of about 850rpm, with AFR in the 14-15:1, then as the throttle is lightly opened in high vacuum condition up to about 2000rpm, I see vacuum at 20”, but AFR takes a pretty steep dive into the 12.5:1 range and stays there. My theory after a lot of zero results tuning is those transfer ports are a bit too big, and I was hoping to get these a little more in line before I start driving it (have some work to do before it is ready to drive). Anyway, is this tuning premature? And regardless of the fact, what methods do you use to plug and re-drill the transition holes? My baseplate has 3 holes per bore. I have some other baseplates I could swap in that have a transfer slot if that is a more preferred design. Thank you in advance for all your input.

 

I tapped a miniature stainless screw in the hole and then I filed the head off of it, flush with the bore.

I drilled the holes by hand with a shortened drill bit that I re-sharpened. A pin vice will not fit in the bore. I made a little knob on the bit out of plumbers epoxy. Apply some pressure with a small lever and turn the bit by hand.

It sounds tedious but the metal is so soft that it is very easy to drill.

what happened in my case (and probably in yours) is that once you drill the hole in your butterfly it allows you to close the butterfly more at idle. This produces a higher vacuum at the transfer port as soon as you crack the throttle, and thus a rich mixture off idle.

Instead of drilling the butterfly I have seen guys notch a small V into the butterfly right in front of the transfer port. This maybe allows that transfer gas to be melded into the idle mixture smoothly(?) and allows you to drill another transfer port slightly higher. I have also seen butterflies that just had a flat spot filed at that area for the same purpose.

This is all stuff that I did 30 to 40 years ago, And some of the details I cannot recall.

I remember ruining two or three carburetors though until I figured out what to do.

 

Awesome! Thanks for the tips. I tried a different baseplate today and finally saw a lean condition- unfortunately way too lean as the idle mixture diameter was too small apparently. I charted both baseplates with drill bits after this and am scheming a hybrid of the two. For now I just took my original baseplate and filled the first transfer hole with JB Weld. I figure it will be easy enough to undo if this doesn’t work. If any of this turns out good, I’ll report back! I read and re-read your posts 2-3x before I realized what you meant regarding the transfer ports lol. Thanks for the tech!