Tri Power issues what to do ?
Thread Starter
Racer
Joined: May 2008
Posts: 323
Likes: 0
From: ********** New York
Tri Power issues what to do ?
sorry if I should have posted this in general,But here to scoop. We have a 69 w/ a 427ci 435hp 460fpt and a tri-pain in the a** vacume setup. Sense we are from NY the car is really only driven in the summer and after the car sits for the winter I always have to tweak the carbs to get her running. I pretty mechanically inclined but when it comes to the tri power set up I feel like using a 32oz dead blow hammer to solve the problem.
I'm wondering what you other tri-power vehical owners would do? I debating on pulling the TP & IM vacume packing it and throw on a new intake with a holly 650. This way we can actually enjoy the car with out having to carb tweak everytime it sits more than 30 days. So I ask you all do you have a better suggestion & if not where would you shop the intake and carb other than the local speed shop?
I'm wondering what you other tri-power vehical owners would do? I debating on pulling the TP & IM vacume packing it and throw on a new intake with a holly 650. This way we can actually enjoy the car with out having to carb tweak everytime it sits more than 30 days. So I ask you all do you have a better suggestion & if not where would you shop the intake and carb other than the local speed shop?
Pro
Joined: Aug 2006
Posts: 647
Likes: 12
From: Midwest
What is the condition of your carbs? With my original carbs I was always tweaking them to get the car to run right. I shelved my carbs and bought a brand new set of carbs from holley. It was like night and day. All I need to do now is see which springs work best in the vacuum pods. Before I bought the new carbs I did put an L-88 intake with a holley 850. I liked that setup but, I am happier with the original setup with the new carbs. You could also have your carbs professionally rebuilt; the carbs are prone to warping and often need to be trued by someone who has the right equipment.
Thread Starter
Racer
Joined: May 2008
Posts: 323
Likes: 0
From: ********** New York
I had the carbs rebuilt 4 seasons ago used the car 10-15 times that season haven't use it sense but when I put the car away I drained the fuel and ran what was leftin the lines dry. Here is what is really pissing me off I'm assuming the gaskets are dry rotted when I re fueled dumped alittle fuel in the center carb to prime and it just pissed out from the base gaskit on the carb and the gasket between the carb and intake. Even after I had the carbs rebulit I had to play with them. I guess I should just do the gaskets and take the car to real mechanic and have them set the carbs.
Let me ask you guys if your car sits for 6 months or sodo you have to play with the carbs?
Let me ask you guys if your car sits for 6 months or sodo you have to play with the carbs?
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
I had the carbs rebuilt 4 seasons ago used the car 10-15 times that season haven't use it sense but when I put the car away I drained the fuel and ran what was leftin the lines dry. Here is what is really pissing me off I'm assuming the gaskets are dry rotted when I re fueled dumped alittle fuel in the center carb to prime and it just pissed out from the base gaskit on the carb and the gasket between the carb and intake. Even after I had the carbs rebulit I had to play with them. I guess I should just do the gaskets and take the car to real mechanic and have them set the carbs.
Let me ask you guys if your car sits for 6 months or sodo you have to play with the carbs?
Let me ask you guys if your car sits for 6 months or sodo you have to play with the carbs?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Disconnect the vacuum systems on the end carbs and install some solid linkage. Run the center carb only until about 50-60% throttle, then have the end carbs come at that point. All carbs to be full open at WOT. You can leave the vacuum pods on there for looks, if you want.
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Melting Slicks
Joined: Mar 2008
Posts: 2,336
Likes: 1
From: North Bellmore Ny
St. Jude Donor '09
I have no problems with the adjustments here are a couple of web sites that have helped me with the adjustments needed I only set it once and no problem so far.
http://www.holley.com/data/TechServi...ded%20View.pdf
http://www.corvettefaq.com/c3/tripower/
http://www.holley.com/data/TechServi...ded%20View.pdf
http://www.corvettefaq.com/c3/tripower/
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Disconnect the vacuum systems on the end carbs and install some solid linkage. Run the center carb only until about 50-60% throttle, then have the end carbs come at that point. All carbs to be full open at WOT. You can leave the vacuum pods on there for looks, if you want.
You may not realize the fact that the end carbs have no provision for accelerator pumps.
Melting Slicks
Joined: Mar 2008
Posts: 2,336
Likes: 1
From: North Bellmore Ny
St. Jude Donor '09
http://www.corvettefaq.com/c3/tripower/
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
OK....so the center carb has the accelerator pump and the end carbs regulate fuel flow based on airflow through them. DUH! So what's new? As with most 3x2 systems, the center carb is what the engine runs on for normal operation and cruise, and the end carbs come in when the throttle is opened 'as required'. On this Holley system, some vacuum cans 'decide' when you can get gas....and with mechanical linkage, I can decide when to open them up. Hmmmm. I hope the original poster now understands how much 'better' the vacuum system is...or should be....or according to engineering design, it was anticipated to be better???? Perhaps the regulation of the outboard carbs by some vacuum 'magic' is why folks have so much trouble setting them up?
P.S. What does the lack of accelerator pumps in the end carbs have to do with anything....really?
P.S. What does the lack of accelerator pumps in the end carbs have to do with anything....really?
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
It mainly has to do when you dump the gas pedal to the floor at low RPM opening 6 carb holes with no vacuum demand hence no fuel being sucked in at that moment , hence the motor will bog.
When you slowly accellerate and only have the gas pedal depressed in accordance with RPM, the manual linkage will work fine.
My tripower also sits for 5 month during winter and has no problems to start and run clean except that it requires a bit of cranking the first time to fill the carb with fuel.
I overhauled them myself with seal kits. Of course I couldn't tue them in case they where warped.
Rgds. Günther
It mainly has to do when you dump the gas pedal to the floor at low RPM opening 6 carb holes with no vacuum demand hence no fuel being sucked in at that moment , hence the motor will bog.
When you slowly accellerate and only have the gas pedal depressed in accordance with RPM, the manual linkage will work fine.
My tripower also sits for 5 month during winter and has no problems to start and run clean except that it requires a bit of cranking the first time to fill the carb with fuel.
I overhauled them myself with seal kits. Of course I couldn't tue them in case they where warped.
Rgds. Günther
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Every tri-power I ever had [or worked on] had the accel pump in the center carb...and it was sized and adjusted to that motor's needs. That was plenty to eliminate WOT 'bog'. If that wasn't the case, you couldn't run decently on just the center carb. Anyway, my 2 cents is to go with hard linkage and disengage the "smart" vacuum system stuff.
Thread Starter
Racer
Joined: May 2008
Posts: 323
Likes: 0
From: ********** New York
Disconnect the vacuum systems on the end carbs and install some solid linkage. Run the center carb only until about 50-60% throttle, then have the end carbs come at that point. All carbs to be full open at WOT. You can leave the vacuum pods on there for looks, if you want.
Okay when I we got the car years ago this is the way the carbs were setup. When I did the resto I had the carbs rebuilt pulled apart the mechanical linkage and installed the factory vacume/mech setup.
So hear is the verdict guy I'm keeping the tri-power. I called my father-in-law who is a old school mechanic and he volunteered to come overand adjust them correctly for me so.I haveto say 7T1 that was the 1st thing he suggested to me as well in any eventI will post some pics when I'm done. Oh that was pics of the whole shot LOL. Thanks guys
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Hey, I think it's neat that you're willing to try the factory set-up; good luck and I hope you and Dad are successful. I just didn't buy the negative feedback on my suggestion [as it didn't have any real merit]. Tell us how it came out. 
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
Every tri-power I ever had [or worked on] had the accel pump in the center carb...and it was sized and adjusted to that motor's needs. That was plenty to eliminate WOT 'bog'.
Yes, that's why Holley DP carbs have accellerator pumps on primary and secondary side. So if your right, we could eliminate the one on the 2ndary side and save some fuel.
Anyway, everybody as he likes.
Rgds. Günther
Every tri-power I ever had [or worked on] had the accel pump in the center carb...and it was sized and adjusted to that motor's needs. That was plenty to eliminate WOT 'bog'.
Yes, that's why Holley DP carbs have accellerator pumps on primary and secondary side. So if your right, we could eliminate the one on the 2ndary side and save some fuel.
Anyway, everybody as he likes.
Rgds. Günther