DIY LS3 Intake Porting + Radius Rods
 

Hey there folks. Just sharing this project I've been working on. I had an extra LS3 intake laying around and decided I would try my hand at porting it. I have ported aluminum intakes before with good results but never an OEM plastic one.So, I figured, what the heck. This intake will be going on my LS3 2011 C6 along with a 103mm throttle body when I install my cam. I'm hoping to test and compare it to the untouched stock intake that is on the car now. Anyway, I made a video (boring lol) of me showing what I did to the intake, where I cut, sanded and ported as well as what I learned along the way. Curious to see what gains I may see but either way its cool when you know you did it yourself.
Things I did, 1) opened up intake to accept 103mm tb and smoothed out opening transition. 2) Removed EGR tube, 3) removed center posts and filled holes with epoxy, 4) sanded and smoothed down any ridges including those along the runners and roof areas

https://cimg5.ibsrv.net/gimg/www.cor...f36ed9934a.jpg
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Rough cuts. Just getting started opening up the intake for the bigger tb
https://cimg2.ibsrv.net/gimg/www.cor...681d47596f.jpg

Sanding away. Removal of center post, EGR tube and sanding of casting ridges.
https://cimg4.ibsrv.net/gimg/www.cor...edcde1e6c3.jpg

Epoxy holes where support columns were
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Basically finished. Need to clean up before install.
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No more obstructions.
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A look inside a stock intake. You can see all the things in the way of airflow.

You Tube

Sub'd...when do you anticipate installing/testing it?

Have you considered installing rods?

Im hoping towards the end of this month or sooner if possible. Waiting for a lift to get freed up at my buddies shop.

I have. I need to look around and see what may work in terms of rod size and design. What I would like to do is test without and then with the rods to see if there's a difference in hp/tq.

https://cimg2.ibsrv.net/gimg/www.cor...517428573c.jpg

Making stainless radius rods for the intake. Decided not to be lazy haha. So many claim that the rods are the big difference makers so we'll see. Will share more info when done pretty soon.

https://cimg3.ibsrv.net/gimg/www.cor...eedc3aa467.jpg

Went with 6061 Ultra-Corrosive Resistant Architectural Grade Alloy, T6 Temper aluminum 1/4" half round rods vs a round rod. We'll see how well it works.
https://cimg9.ibsrv.net/gimg/www.cor...dc91ab91a8.jpg

The rods are extremely light and are held on by high temp epoxy. Epoxy runs the full length of the rods.

Looks awesome! How many hours do you have into it? Let us know how the testing goes, solid work!

Thanks man. I have probably 8-10hrs into it but now that I know and made the tools to do the job, it would take me a few hours less if I were to do it again. Hoping to see some gains as well hopefully. I already have a few guys wanting for me to port their intakes too lol.

Well, I got the results for the testing on the LS3 intake that I ported. A stock LS3 intake, a FAST 102 and a sheet metal (eBay style) Fitech intake were also tested.
This was on a cam only stock LS3. Cam specs were 244/256 duration .615 lift, 112* lsa

Stock intake: 556hp/510ftlbs
My ported intake: 570hp/512ftlbs
Fast 102: 572hp/507ftlbs
Fitech: 585hp/470ftlbs

To say the least I was very surprised and excited with the results. I was most surprised of how my intake carried the power to 7000rpm and how good the power and torque curves looked. It responded very well to this engine combo. I think the Fast will shine best on a big cube motor so that will be the next test. For now I'm a happy camper. It was nice to see the little tweaks and mods I did pay off as real world results.
Also the power band of my intake killed the Fitech everywhere below 6400rpm. After that the Fitech pulled to 7200 or so and made 585 peak hp. Not sure if the loss of power and torque everywhere else would be worth it. Its not the right intake for this application.
As always these results are just for this particular combo that we tested and every part on a motor should be chosen specific for it's use and application for the best results. Every combo is different.

Ported intake is the blue line
https://cimg4.ibsrv.net/gimg/www.cor...937d60eefc.jpg
Ported intake is blue line, Fitech is red
https://cimg9.ibsrv.net/gimg/www.cor...1a50548676.jpg
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The ported intake pull on this graph was not the best (had to look through all the files. Each intake had about 4 pulls) The ported one pulled cleaner to 7000rpm after more pulls with the dyno software making adjustments. Stock intake averaged 556hp after 4 pulls. Ported one averaged 570hp

I tried finding the best pulls for each intake to make the comparison graphs but there was a lot of pull files and they weren't named. So the numbers I posted were the best numbers that each intake made. They made pulls with each intake untill they stopped making power. The software is self learning and each pull makes better power. Once it makes the same power a couple pulls in a row you know that's about what it's going to make. That kept the testing a bit more even.

Did you check the difference? Do the rods make a big difference?

Very nice homework, i like it! :thumbs:

Thank you.
I did not get to test the intake without vs with the rods. However I started porting another intake today for someone and I just may conduct that test since they'll be breaking in the motor on the engine dyno. I'll post results if I do.