BritGreen68

Hello, I am rebuilding my 427 400hp motor for my 68' and want your input. It doesn't have the original heads, intake, or carb setup so want the motor to put out much more than 400 horsepower. I am going to put new aluminum ARP heads, MSD Ignition, and a better cam. I was planning on using the Edelbrock Air Gap intake and appropriate Holley Carb which would also mean I will have to go to the L88 hood.
Well, I just had a thought. Would the factory Tri-Power setup put out just as much horsepower as the Air Gap setup? Other than the fact that the setup won't be cheap. What do you guys think? If I put the Tri-Power setup on I can keep my original hood which I really like AND it's a Tripower. What do you guys think?

Jud Chapin

Yes, the original factory tri-power set is very costly. I sold the one on my '67 (in good & running shape) a few years ago and got $3000 for it. However, I don't know what they go for today.

hurry88

If you use the 435hp manifold, the square port one rather than the stock round one you will be right there with the new heads and keep your hood. That manifold and carb set is not cheap, but it will look original and run like a bear.

BarryK

the tri-powered setup is definitely cool looking but it was put on the motor at the factory for "marketing" reasons, not performance. A good intake and single carb set-up will outperform the tri-power set-up (look at the L88 where they went with a single carb rather than a tri-powered).

If your goal is the MOST performance go with a single carb. If you want GOOD performance and a cool "wow" factor for shows or just visual showing off than go with the tri-powered.

400hp427vette

The tri-power is cool looking but does require attention and the secondaries open at about 3000 rpms. It's very good for gas mileage and attention but I don't see these setups on cars for the fun factor. new they go for about $4300. I could get alot more fun for my money if that was my goal

Wrencher

It'll be close in a mild engine, but the 3x2 does give up flow, making up for it in sheer volume. WFO, it potentially flows almost 1200 CFM if the rest of the engine can handle it! In reality, it's probably closer to 800 actual CFM. That said, if you want all out performance, go with a large single 4V with the appropriate manifold.

My build is an LS-7 454 with the rec port tri-power and modified Stal headers and a variation on the L-88 cam. We'll see how that works and go from there. In definitely want to keep my hood.

Hans

offroadtoyota

The sound of a tri-power is a wonderful thing.

BB427

I wouldnt let go of that tri power bro I just saw 1 selling for selling for 5600 fully rebuilt. the dueces are either 350 or 500 cfm per duece according to a print out I pulled from online.

3JsVette

As has been stated over and over the Tri power has the look (and the cost for that matter) but the single 4BB will run rings around it. Why not do some research with the manifold companies? I would be willing to bet you can find a manifold the fits under the stock hood and it will only give up a very little peak horsepower over the air gap (and may even make just as much or more torque). Will you really notice 10 or maybe less peak horse power on a street car?

68L71

I have run both an 850 double pumper with mechanical secondaries on an L88 intake and my tri-power setup. Properly tuned the tri-power setup out performs the double pumper on my engine. You will be limited in intakes choice for stock hoods…I don’t think the L-88 hood will even clear most air gap intakes. I don’t know what you think, but to me anything higher than a stock L88 hood is ugly unless it is not a street car.

GDaina

You won't be disappointed in the performance......

milo30

I've been thinking about the Barry Grant tri power setup when I get around to replacing my engine. I like their 3 finned air cleaners better than the stock triangle. Gives it a better "wow" factor when the hood is open. I've seen dynos for tri powers as opposed to 4 barrels. They seem to go either way on power depending on the motor but they seem to be pretty similar in HP and TQ.

If it was me, I'd go tri power and be a little different. With gas prices going the way that they are and this will be a daily driver, I might not ever get mine. I'm leaning towards an LS with fuel injection for economy.

If you do it, post some pics so we can see how it fits. I'm probably changing to the same hood as you, either way.

Steve439

That's a tough choice...

On one hand Barry is completely correct.

On the other hand if your car is a documented 400HP the correct setup
will add dollars to its value. I doubt the prices of those manifolds will
go down so it's a pretty good investment. They ain't cheap!

I'd go for the RPM and Holley myself, since you're already going
non-stock with the AFR heads (excellent choice) and stuff.

BritGreen68

You guys all have great input. I looked into the price of a complete Tri-power setup and it isn't cheap at all. The machine shop who is going to do all of the work plans on putting in better pistons, connecting rods, along with the ARP heads. The engine will not be stock although the car will still look stock. I am thinking that the Tri-power setup will work for me. It would look good for car shows and is something different for people to see. If we want to break it down to NASA engineering testing/specs I can deal with some horsepower loss buy not going the Air Gap single carb route. I would not need the extra horsepower for every stop light race. Thanks, Joel