Fed up with tri power

[Rich G.]

[Dick W.]

Re: Fed up with tri power

Have you looked at the FiTech 3X2 electronic FI. Would be great setup and with the air cleaner on it would look stock. I have a 496" with a ProCharger on it in the shop. We tried three different EFI setups before we found one that would produce an acceptable a/f ratio from idle to 6,500 rpms.

[Rich G.]

Re: Fed up with tri power

Dick

I have not, but I will. I assume a new fuel pump and sensor(s) would need to be added. Thanks for the info

Rich.

[Patrick B.]

Re: Fed up with tri power

If you want to use a factory aluminum manifold and a Holley 4 barrel, the 71 LS-6 manifold is the only one that will fit under your hood. If you would rather use a Quadrajet which is much more reliable than a Holley, I think the 69 390hp used an aluminum Quadrajet manifold. I think 68 and 70 390 hp used an iron Quadrajet manifold that would also work and are more plentiful.

[Edward D.]

Re: Fed up with tri power

The GM Q-jet manifolds are all oval port. The 68 L71 has rectangular port heads. There are several GM aluminum rectangular port manifolds for Holleys that will work. You can also go aftermarket with an Edelbrock manifold, just remember to match the port configuration.

[Rich G.]

[Joe L.]

Re: Fed up with tri power

The GM Q-jet manifolds are all oval port. The 68 L71 has rectangular port heads. There are several GM aluminum rectangular port manifolds for Holleys that will work. You can also go aftermarket with an Edelbrock manifold, just remember to match the port configuration.

Edward------


The only GM manifold with rectangular ports and which will fit under a 1968-72 standard big block hood is the LS-6 manifold. No others will work.

As far as aftermarket manifolds, the only one I know of that will work is an Edelbrock single plane manifold. I do not recommend single plane manifolds for street use.

[Chris H.]

[Joe L.]

Re: Fed up with tri power

I have a 68 L71. I’d really like to drive it more than 150 miles a year but too many times there is a problem with the Tri Power setup. If it’s not fuel lines leaking, it’s carbs leaking or floats sticking or fuel leaking down the throat of a secondary flooding out the engine. I’ve had this car for 16 years and tolerated it because I had a shop who could fix things quickly but now I don’t and I’m just to old to screw with it every time I take the cover off.

So, I’m considering taking the whole set up off, storing it away in a safe way and replacing it with a manifold/ 4 barrel combination that works. The heck with date codes. A new carb out of the box would be lovely. I’m looking for suggestions that don’t include trying to fix these carbs again. The next owner can enjoy the tri power carbs. I’m done.

Any suggestions?

Rich

Rich------

If I had a Corvette with 3X2 set-up, the first thing I would do is to remove it and replace it with a single 4 barrel. The 3X2 set-up was all about "glitz" and "cachet" and never interested or impressed me. Never.

[Guest]

Re: Fed up with tri power

Tri- power set up run a simple center 2 barrel Holley remove the both linkage from the both end carburetors and just set up the center Carburetor and see what happens, sound like you got float level adjustments which are very easy to adjust and leaky fitting to deal with.

[Terry M.]

Re: Fed up with tri power

This is the: "the only thing worse than one Holley is three Holeys" thread

[Patrick B.]

[Patrick C.]

Re: Fed up with tri power

FWIW I would not run fuel with ethanol in it.

[Rich G.]

[Robert W.]

Re: Fed up with tri power

It sounds like you need a good mechanic who really, really knows Holley carbs and how to set them up. I know somebody up here in MA (PK Machine, Fitchburg) but its probably too far away. You could give the shop a call and he may know somebody in your area... Finding anyone who really understands carburetion is getting very difficult these days.