Looking good guys! Awesome thread! Wish I had come across it earlier. I've only read the last 6 pages so far. I need to go back to the beginning now. I hope someone there covers porting the inside because from what I saw on page 6 everything looked pretty smooth already.

I started a thread on this and people have mentioned intake flex under vacuum. I figure may be what the posts inside the intake were for. Maybe to support it from collapsing? IDK. Anyone here cut those posts inside of the intake out and have had no issues?

I'm headed to the beginning to read the rest now.

 

For general knowledge on the thread topic...heres some information I found on adhesion to nylon 66.

After reading through some plastic engineering forums I've come to this conclusion. From what I understand, Methacrylate is about your only, and best bet for adhesion, as Nylon is classified as a "difficult to bond plastic".

Nylon and Nylon 66 products require a Methacrylate type of glue/epoxy for proper adhesion.

Types I've found: These are both roughly $20 for 50ML. They also come in larger quantity but require the special gun dispensers.

Plexus MA310 and MA330 (pigmented version of MA310)
Devcon Plastic Welder II

ALSO...Loctite Plastic Bonder Epoxy (readily available at most hardware stores) is also composed of Methacrylate. Price 25ML @ $3.97

The following is a pdf from a company called Plexus whom engineers adhesives. The PDf is on plastic adhesive and material types.

http://www.google.com/url?sa=t&rct=j...69837884,d.aWw

Good sections to read, are the following.
Page 31 - Nylon Infomation
Page 7 - Structural or Performance Adhesives
Page 8 - Methacrylate Adhesives
Epoxy Adhesives

I actually went out and grabbed some of the loctite plastic epoxy from Menards. I just used some scrap pieces to test the stuff out on. I glued the faces of 2 flat pieces together to see how they would bond, and also threw a skim coat on another piece to see how that comes out. It should take about 24hrs to cure. So I'll update once I've check them out. All pieces were scuffed/sanded/cleaned before bonding

 

I used the Loctite stuff on my intake after doing similar research into it. So far, so good. About 150 miles driven and a lot of idle time running. No issues. Just need to make sure to scarf both the intake side and the plug to give a nice, rough and broad area to adhere to. Also, I used a big black plastic spatula to create my plugs. Turns out, pretty much all black plastic spatulas are made of nylon 66...not glass fiber filled, but that isn't critical for small plugs.

 

I used the Plexus MA310 on my LS6 intake to make a repair. That stuff is strong.

 

I think I'm going to try and source this stuff and give it a try myself. I was pretty impressed with the results I got from the loctite version. But I'd imagine the Plexus may be a tad superior?

What kind of repair did you do with the stuff?

Also, Thanks for the input 70camaro! Any pics?

 

I've posted a few before. No in-the-middle step by step stuff, just a few finished. Here goes again:
Attachment 724171

Attachment 724592

Attachment 725110

 

Wow this thread is full of awesome. I have 5.3 I bought for my 04 Colorado, which I already have a LSXRT intake sitting on, but I still have the original intake in my garage, and I also have a TBSS so I may play around with this.

 

If you shave off those larger "bungs" lack of better word on the sides of the intake I would fit a piece of scrape nylon to fill the hole and plastic weld it in.

Then take a roloc disc and air grinder or dremel and dremel in a small ditch maybe 1" out in almost all directions of the recessed ditch. I bought this nice thin metal mesh from urethane supply. Then use your plastic welder and try to melt/embed it into the ditch.

The area you grinded out and after embedding the reinforcing metal mesh should be below the surface of the rest of the intake. Get some more donor nylon plastic and melt it over the metal mesh and build it up so you can later grind and sand it down flush with the rest of the intake and you will never know it was there.

 

Get it here. $30 with shipping. You don't need the gun to apply it. Just do all your work as fast as you can otherwise the tip of the tube will harden shut.... Ask me how I know. Then you have to cut it and it gets messy.
http://www.usplastic.com/catalog/item.aspx?itemid=24934

I had ordered a LS6 intake and it arrived broken from being dropped. The seller sent me a new one at no cost so I gave the repair a shot. I still have the intake on the bench. I decided to paint it to hide the repair so its just in primer right now. Here are some picks of the damage and repair.



I washed it, then repaired the broken vacuumed nipple (ran a drill bit through after to make sure the hole was open), then repaired the circle the MAP port goes into, and lastly rebounded that circle to the intake from the inside. The way this one broke I was able to get that MAP port out without breaking the tabs.



Sand smooth




That's where I am at now. I'll paint it and then put the MAP port back in and see how it goes. The Plexus is strong so I think the success or failure will be dependent on me and my ability to get a good seal where the MAP port's o-ring meets my repair.

 

Its been a while since there has been a post in this thread, and I am wonder from those of you who have done the shaved truck intake manifold, how is it holding up long term?

I have a 325 truck engine myself and had planned to do the intake shaving, but haven't got to it yet.

I had, however, shared this thread with online acquaintances on another forum. Several of them went forward and shaved their intakes. After a few months of usage, a couple of those individuals backed out. One person stated that as he watched his engine run (obviously parked), it appeared that the intake was going to collapse in on itself and ended up with one of those OEM style Dorman intakes. I also had another similar story with worse results, but I question whether it was due to the strength of the shaved intake, or the skillset of the person who performed the intake shaving.

Either way, I suspect that the above incidents are isolated and I am wondering how the shaved intakes are holding up, long term, from those of you who have done this and have them installed on your engine long term?

Thanks for your replies.

 

I've been daily driving mine for over 9 months now and I beat the **** out of it. Plenty of WOT pulls. I havent seen any issues to not yet. It's not at stock 5.3 either. Its about 425 chp.

Only thing that I would do different and will do on my next one, is that instead of using body filler to smooth the top, I will use something called Lab-Metal. It's much stronger. A guy posted a comment below my video of shaving these intakes, that he used Labmetal and has run it on ten pounds of boost so far with no problems. He plans to test it with more boost this summer.

Here's the link to the video:

 

Here are some videos of some of the abuse that I put it through.

Big burnout video:



Lots of WOT pulls:

 

My Chevy II Wagon with a shaved 5.3 is my daily driver and it's been on the road for 1-1/2 years, works great and still looks like it did the day I put the car together.

 

Here is mine on my volvo

 

So what is everyone using to cut the large pieces off the top?
I think i've seen a sawsall so far, anything else?

 

IMO a sawsall works excellent. I tried a cutting disc at first but that would create too much heat that it'd melt the plastic, clog the disc and make a mess.

 

I also have this concern. I've watched videos on Youtube of guys revving their LS engines with shaved intakes and you can see the top flexing. I have over 30 years of plastics / tool engineering experience in the OEM automotive world and can say from experience that GM designed LS intakes with structural ribbing and gussets for good reason. I really like the look of a shaved truck intake and would like to do it to my set up but not at the expense of reliability.

 

That gives me another idea. You could leave the lower profile ribs since the taller pieces that are cut off are there to support the intake cover and not reinforce the intake. Then you could put a layer of you choice of filler over those ribs that were left to smooth it all out. The ribs will help strength and the thick layer of something like Lab-metal would strengthen is more.

I've rev'd mine and havent seen any flex. Maybe i need to actually put a camera close to it to catch it, but I couldn't see it while standing over it.

 

These are by far some of the best smoothed intakes I've seen.

 

Daily drove mine for the last year and 4,000 miles...yeah I don't have to drive very far very often. In the middle of upgrading to a LSXrT right now and while inspecting the shaved intake when I removed it I noticed one location was slightly cracked and showed signs of leaking. All other areas are perfect. I'm going to sand that area down, apply a nice thick layer of resin and repaint it. It will be for sale soon for a very reasonable price plus shipping.