Thread: Tri-Power Carbs build.

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Mike Great article. Have rebuilt many rochester myself and there are places where you can get replacement parts. Just can't think of them off the top of my head.

I've even been able to get pretty complete rebuild kits at NAPA to do the W30 tripower carbs on my Sons Olds engine, so they should have kits for these regular 2 barrel Rochesters.

By the way, talking about carbs, about a year ago we bought an ultrasonic parts cleaner at work to clean carbs, primarily. Up until then we used the common caustic carb cleaning solution. This has proven to be one of the better purchases we have made. It uses tap water and soap, and the carbs come out cleaner and quicker than the old method. It heats the water to a very high temperature, and blasts the parts clean with ultrasonic pulses.

We have cut our time and costs significantly, and the cleaner has paid for itself mny times over. Nice thing is, I am able to stay after work and use it to clean my own stuff.

Don

Mike Amoung my many hobbies is coin collecting and I use the same thing on my coins to clean the dirt,etc. that accumulate from coins I find buried in yards, beaches, etc. I have never tried it on carb parts but as you say it must work and I'll have to try it out.

Mike, this thread has me thinking I can build up a 3x2 setup myself. Do u happen to know what vehicles i should be looking at that came with fuel side inlets on the 2g's?

Great info Mike, I'm working on a 3-2 set up for a small block chev 350. Stock heads with a mild cam,turbo 350, stock stall.The first mod. I did, was to plug the idle screw holes, along with some vaccum holes in the bottom base screw hole,replace the throttle plates with thicker ones from Speedway. Also modified the old shafts to accept the plates, was wondering what jet sizes to start with, all three carbs have .042 jets, what float levels to use, and do you still use the accel. pumps on the end carbs?

The .042 should be about right for the outboards, I'd try about .048s in the center to start.

Leave the accelerator pumps otherwise it will lean out way too much when you kick them in.

I normally set the float level just a bit lower than stock mostly because of the high summer temp and the 4500+ altitude I'm at. I would probably recommend that you set end carbs just a bit lower too. Under most conditions the fuel in them sits as the car will be running mostly on the center carb. The fuel inthese carbs has a lot more chance to heat soak and expand than the fuel in the center carb which is being used and replenished.

Mike, thanks for the tip on the idle screw adjuster tool. That's a real buggerboo on my F-380 Edelbrock intake on the 390. The three rochesters set so close together, I've been having a heck of time adjust the idle on the center carb. As soon as it gets warm the carbs are coming off and I'll do this simple adaption. I don't know why I didn't see this thread last fall, must be CRS.

No problem Duane. Another little tip that might help a bit, some of the Rochesters have a boss cast into the base plate right beside the idle screws, it sometimes helps to remove these to get the adjusting tool in.

By the way how do you like the edelbrock intake? I've seen them on E Bay from time to time and wonderered how well they work. Even thought about picking one up, but as I only have 1 FE (and it's already got a T Bird intake on it) that would cause me to just build another engine to find out.

very timely article!,that will cure some of the carb stumbles when mashing the go button

Mike, the only thing I don't like about the Edelbrock F-380 is the three carbs are really, really close together. It performs just fine. I had put the Speedway conversion kit on the carbs which really fixed it up. Had tried some of the baseplate mods you did, but still had hiccups.

Mike, read your article and have a question..............how do you keep the stock throttle plates from sticking in the bores when they are tightly closed as to prevent vacuum leaks? I have seen no mention of this and it is a very real issue doing the secondaries with standard throttle plates.

Possible I have been lucky with this as I have never had a problem with it. I do on occasion have an end carb that that when opening by hand you can feel a slight sticking, but it has never been noticable when opening the carbs with the gas peddle.

I was reading the article you had written, I guess a while ago, and thought maybe you could help me, if you would. I purchased a set of rochester carbs for a tri carb set up. Not knowing much about this, obviously, I may have messed up. The center carb is a 2GV, I believe, according to the Haynes rochester manual. The model number is 7038570. I have only this one carb on the car at this time, and I'm having a heck of a time getting it to idle right. I have looked for vacuum leaks, and I don't think I have any. This carb has no choke system on it, and I understand that the 2GV's received their choking off the intake manifold some how. So, is there a "universal" choke system that I can get for this? Right now I have a cable attached, so I can work the choke, but obviously this is not a good deal. Or, do I need to get a different center carb? At a hand operated (throttle cable is not connected) high rpm, the engine runs fine. But I having trouble getting the idle right; and the cam on the drivers side, with nothing on the other side on the choke is a real pain. Any ideas are welcome -
Thanks much - kip younger

can you post a pic of you're setup? minus air cleaners!
whats the other carbs? do you have it installed tightly & not sucking any
tramp air from it's mounts?
a manual choke is o.k.,however i spring load mine!,that way when i release the choke it stays open,no chance of running partway closed

As Donnie mentioned a picture would help along with an idea about what the engine/car is.