Intake Manifold Trumpets...
- Thread starter illSHOyou
- Start date
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Off Road SHO
Moderator
They are made of steel, coated with zinc I believe. And they polish up really nice of course.
Why do you ask?
Tom
Why do you ask?
Tom
platoribs
Live to Drive
I think he might be wanting to expand them to get a larger ID, however I could be mistaken...
Off Road SHO
Moderator
Dolt! I just noticed this is in the V-8 section. My reply is based on the 1st and 2nd Gen V-6's. My bad. Carry on.
Tom
I bet they would still polish up nice.
Tom
I bet they would still polish up nice.
Cause I want to play with adjusting them and re-weld.
I am thinking about shortening the first trumpet on each set closest to the tb to improve airflow into the intake plenum. A staggered intake velocity stack by the entree.
kevinspann
Don't take my advice.
Looks nice. But looking at the plenum, it seems like it's plenty large enough for a 3.4L v-8.
Yeah, its probably 3/4 the volume of the engine.
SuperHO
Mental Patient
so that's what a clean V8 intake looks like inside....
Close anyway. I am still working on it. I am looking at shortening the first trumpet on each row. Starting at the front and taken them down 3/8" or 1/2"
So, when you look into that opening the two trumpets at the beginning will be shorter, and hopefully allow the air flow a better approach, and distribution between runners. The 1/2" difference will only alter the tuning a touch higher on those first two but more important allow more airflow to the rear trumpets.
I think I can accomplish this by cutting the runners at the bottom. Sand out the center plate with a round barrel sander and then slide the runner to the desired height. Once you have the height braze the two pieces together with silver solder. Clean off any excess...
newshofan
New Member
Looks great I can't wait to hear how they work out.
kevinspann
Don't take my advice.
What are you hoping to gain?
Hoping for better flow distribution across all cylinders. I think shortening the first two trumpets assist better with air distribution in the intake plenum. The intake charge is at a high velocity going into the intake plenum and while the increase in cross-section area will slow the air down and increase pressure, the first thing the air has to do is negotiate a 90 degree turn and slams into the first two trumpets. I could imagine the potential for turbulence.
The first two trumpets always have more than enough air provided by the plenum entree, it’s the rear cylinders that really suffer and lack air flow. Usually the front cylinders run lean and the back run rich.
The idea is with the first two runners cut down closer to the floor of the manifold we can open up the flow at the entree and allow the air to skip over the first two trumpets and feed the rear cylinders better. Also reducing the intake length will increase peak power by a touch on those two cylinder(or move the power in those cylinders) but will also reduce velocity. Velocity loss isn’t a problem though as the air is already moving fast at that point. So were looking at overall tradeoff and fair trade across all cylinders.
I don’t know if anybody noticed but one of the stock trumpet sets has a longer trumpet at the very end.
Trumpet on the far left:
So, with multiply stepped runners we could maybe expect to broaden the torque curve at the expense of maybe 1-2 peak hp. But the 1-2 hp peak loss maybe worth the overall gain of say 5-10 hp from all the modifications.
To recap:
Improved air distribution
Reduced turbulence
This is my “Hope”
Also, it would be very easy to modify trumpet sets in many ways. One could reduce all runners by .75 inch and move peak hp up 500-800 rpm? It would be really easy to start dropping different sets in on the dyno. One could make pulls with the new set every 10 min.
The first two trumpets always have more than enough air provided by the plenum entree, it’s the rear cylinders that really suffer and lack air flow. Usually the front cylinders run lean and the back run rich.
The idea is with the first two runners cut down closer to the floor of the manifold we can open up the flow at the entree and allow the air to skip over the first two trumpets and feed the rear cylinders better. Also reducing the intake length will increase peak power by a touch on those two cylinder(or move the power in those cylinders) but will also reduce velocity. Velocity loss isn’t a problem though as the air is already moving fast at that point. So were looking at overall tradeoff and fair trade across all cylinders.
I don’t know if anybody noticed but one of the stock trumpet sets has a longer trumpet at the very end.
Trumpet on the far left:
So, with multiply stepped runners we could maybe expect to broaden the torque curve at the expense of maybe 1-2 peak hp. But the 1-2 hp peak loss maybe worth the overall gain of say 5-10 hp from all the modifications.
To recap:
Improved air distribution
Reduced turbulence
This is my “Hope”
Also, it would be very easy to modify trumpet sets in many ways. One could reduce all runners by .75 inch and move peak hp up 500-800 rpm? It would be really easy to start dropping different sets in on the dyno. One could make pulls with the new set every 10 min.
newshofan
New Member
If you do a search on here you come across a few interesting threads about different parts of the intake. Including the trumprets.
I know I took mine out once. Drove about 5 miles and put them back in. The car was even doggier than normal.
Nice pics. How did you take them?
If you need more trumpets I have a couple of sets you can have for shipping cost.
Nice pics. How did you take them?
If you need more trumpets I have a couple of sets you can have for shipping cost.
iPhone
amazing right? I love my new phone. I would be interested in the trumpet sets. I'm a little short on cash this week because of mortgage and stuff, but I would have it next weekend....
