newschool72

iTrader: (12)

Anyone have any real world results from a good port match on a carb style intake? Ive heard mixed reviews on whether it really makes any difference in HP or TQ. Im in the process of doing some NO dollar mods to tweak a little better ET out of the ol LS3 before I go back to the track in the spring. So far Ive taken a little weight out of the car (25lbs) and am working on a few other ideas to drop a little more. I doubt I will find much more than 50-60lbs total without losing some of the comforts I built into the car.
So that leaves me with a few tweaks to increase the engine output . Hit me with some #s on port matching, guys. I need another 20 HP or so, to maybe push me to 10.99. That's either 200lbs of weight or 20 HP more power. It looks like I will have to get 15 HP and 50lbs weight reduction to reach my goal without giving up the AC or power steering. The easy way would be to drop the AC (40lbs) and buy an electric water pump. That would get me about 100lbs reduction and free up about 15hp. I just really enjoy the AC on those hot, humid GA summer days!!

speedtigger

iTrader: (16)

I have done this quite a bit over the years. I would offer to you that there is no one simple answer to the question. There are many variables.

One important variable is who is doing the match porting and what do they do when doing it. A perfect example of this is my latest build. I have CNC ported heads that have significantly increased runner cross sectional area. So, the intake needed to be cut a lot. I was very busy in my life at the time, so I asked around on The Bullet for the best porting outfits. I picked one from the suggestions and sent the intake to him. When I got it back, all I could do was shake my head. The guy opened up the intake port right at the gasket surface, but did not port the rest of the runner to eliminate the reverse taper. It was a joke. So, I took a few hours and fixed his amateur work. In this case, a lot of work needed to be done to the intake because the heads were bigger. And, in this case, it was worth about an estimated 5-10 HP.

The next thing that is important in match porting is actually know how to line the runners up to assure there is a good matchup measurement and a good final alignment to make the project a success. Here is a link to my method:

https://ls1tech.com/forums/generatio...ted-heads.html

As you will see in the pictures in the thread above, the Victor Jr runners port alignment was off significantly from the PRC CNC heads. How far off your ports are will be a factor in the value of the work.

In general, the higher the velocity, the more value a port match will generally have. In the case of large heads where the velocity may not be as high, misalignment turbulence will be less and generally have less impact.

I would not expect a huge gain in your application, but there may be some measurable results. You will just have to follow the alignment procedure and check it out. And make sure you don't create a reverse taper scenario. Changes in cross sectional area can be just as problematic as poor port alignment.

newschool72

iTrader: (12)

Ive ported a few in the past, so Im familiar with making sure everything lines up right, I just was hoping a few guys on here might have some good comparisons, before and after, to see if its worth my time. I think the intake runners on the dual plane help out with port velocity, a little anyway, I just don't know if its worth the time and effort to match everything up. Ive seen where people claim it doesn't help much, because most of the intake flow is more in the middle of the runner at WOT, so they claim the walls don't contribute much to the overall flow. From what I could see, the runners matched up pretty good, but with the dual plane its harder to see than a vic jr.