Advice on drilling aluminium (inlet)

1. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

   #1 31st May 2012, 19:29

   Right, I'm modify a S1 inlet to put on my vtr rebuild, but I'm using my bigger ICV as that's what my current engine uses. So have to drill into the inlet for the hose.
   
   But I'm just wanting advice on what the best drill bits/methods are to use to drill a 12/13mm hole so I can tap in a threaded hose adapter.
   
   
   
   Cheers.
2. user_34323 Saxperience Post Whore Joined: May 2009 ringwood Posts: 6305 suzuki swift 1.2 sz3

   #2 31st May 2012, 19:31

   I'm no expert but, drill a nice pilot hole, and go up in increments up 1mm under the size you need and the tap a thread. Use good quality drill bits!
3. user_16747 Banned Joined: Jul 2007 Posts: 4328

   #3 31st May 2012, 19:59

   What he said or for a few quid an engineering shop would do it
4. gazza808 Frequent Poster Joined: Jul 2007 Posts: 591

   #4 31st May 2012, 20:49

   If I was doing that at work,
   I,d drill a 3mm pilot, then 6mm, then tapping size pending what thread,
   
   If that's really thin you may not get a decent thread form depending on the thread pitch,
   Which would mean you may want a bung welding on an drill and tap that.
5. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

   #5 31st May 2012, 21:12

   Cheers fellas. Didn't think of the threaded problem actually.
   
   The adapter I'm using is like this:
   
   
   So I guess if tapping it in is a problem, then I could get a mate to weld it in...?
6. gazza808 Frequent Poster Joined: Jul 2007 Posts: 591

   #6 31st May 2012, 21:15

   Do you know what thread it it?
   
   If it's npt you'll probs get away with it, due to the taper tighening up on it's self just use a good helping of thread sealant.
7. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

   #7 31st May 2012, 21:26

   Not sure on the thread pitch gaz. Is there a way of calculating it by measuring the length and the amount of threads?
8. Gandi699 Saxperience Post Whore Joined: Apr 2011 Posts: 9100 Amazon green VTR 16v, Inferno RS clio 182

   #8 31st May 2012, 21:40

   If you cant get a thread to tap in it (unlikely) can you not use some sort of compression fitting in two halves, then just screw it down to form a seal?
9. blackie_2k5 Saxperience Hardcore! Joined: Oct 2008 Birtley Posts: 22253 VTR Turbo, 106 xsi track slag, Transit recovery, B

   #9 31st May 2012, 21:47

   If your using a gas or airline fitting like that, measure it, drill a hole 1mm smaller the the fitting, don't try tapping it
   
   Just wrap it in ptfe tape, and turn it In with a spanner or socket keeping it straight
   
   It'll cut it's own thread
   
   
   Be VERY careful not to put it on an angle, soon as its got some resistance near the end of the threads, stop tightening, or you'll strip it
   
   I'd don't reccomend doing it this way, but your not gonna tap a decent thread for that on these inlets, I have used this method before though, if your careful it works, but only on n/a cars, boosted will just blow through the gap lol
   
   Best bet is get a pipe or boss tig'd on and use rubber pipe and jubilees to join it
10. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #10 31st May 2012, 22:09

    Cheers gandi and blackie, 'should' be sorting it out this weekend so will see what options we've got to play with. Want to get it done so I can start working on the bottom end.
11. Gareth_R Established Member Joined: Mar 2010 Basildon, Essex Posts: 1042 Citroen AX VTS

    #11 31st May 2012, 22:17

    Drill on a slow speed - you want torque not speed to cut the metal, too fast and you'll just glaze it
12. tweeqd Established Member Joined: Mar 2006 Farnham Surrey Posts: 1542 AX GT 16v turbo 6 speed with NOS 205 gti6 E 320

    #12 31st May 2012, 22:40

    id not put it on the back but on the opposite end to the throttle body, if it comes of the back like you have it in the pic it will prob hit the bulkhead
13. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #13 31st May 2012, 22:49

    ^ It's going in my 306 so has a decent amount of space compared. I've measured it all and it should fit perfectly besides the alternator:
    
    
14. tweeqd Established Member Joined: Mar 2006 Farnham Surrey Posts: 1542 AX GT 16v turbo 6 speed with NOS 205 gti6 E 320

    #14 31st May 2012, 22:58

    cool as long as there is room lol
    
    keep the drill straight and it will be fine, ive drilled the hell out of mine and run boost with no issues
    
    
    
15. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #15 31st May 2012, 23:07

    Quote:

    Originally Posted by tweeqd ive drilled the hell out of mine and run boost with no issues

    
    What the F.....
    
    No kidding huh!!??
16. blackie_2k5 Saxperience Hardcore! Joined: Oct 2008 Birtley Posts: 22253 VTR Turbo, 106 xsi track slag, Transit recovery, B

    #16 31st May 2012, 23:13

    I asked that in the old thread Martin
    
    One thing I'll say is, the plenum is a lot thinner the the runners, especially on the rear where your trying, thickest part is left side of the plenum as Martin said (thats where its joined as you can see by the pic)
    
    They're a minefield in terms of wall thickness, but you can generally tell by looking where is thick/thin
17. blackie_2k5 Saxperience Hardcore! Joined: Oct 2008 Birtley Posts: 22253 VTR Turbo, 106 xsi track slag, Transit recovery, B

    #17 31st May 2012, 23:22

    best pic i have of an airline fitting tapped in.. (on shelf taped up but you get the idea)
    
    
    
18. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #18 31st May 2012, 23:44

    I did make another piping route but wasn't sure on its location. As I thought the more central between the 4 intakes: the better. But that might just be a load of crap?
    
    
19. blackie_2k5 Saxperience Hardcore! Joined: Oct 2008 Birtley Posts: 22253 VTR Turbo, 106 xsi track slag, Transit recovery, B

    #19 31st May 2012, 23:52

    idle valve works by bleeding air in to keep the engine ticking over
    
    works via the map sensor on vacuum..long as you got no air leaks it doesnt matter where on the inlet you put it..long as its after the TB
20. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #20 2nd June 2012, 16:57

    Right, well me and my dads mate cracked on and managed to drill the mani and fit the adapter. The biggest drill bit I had was a 12.5mm but it was good enough for the tappered thread to fit into albeit not all the way in but worked out great:
    
    
    
    Took your advice blackie and just drilled the hole then wound the adapter in to create its own thread, worked a treat!. Then finished it off by thread locking it and putting sealant round the base.:
    
    
    
    
    
    Just hope my measurements are correct now...
21. gretsch-drummer Infrequent Poster Joined: Apr 2012 Moortown, Leeds Posts: 156 5dr Bianca 306

    #21 2nd June 2012, 22:13

    Also, people of Sax-p: Don't feel defeated when you don't have a big enough socket to press through your new cam seal....
    
    Just find a porcelain egg cup like I did:
    
    
    And it didn't even crack!
22. Gandi699 Saxperience Post Whore Joined: Apr 2011 Posts: 9100 Amazon green VTR 16v, Inferno RS clio 182

    #22 3rd June 2012, 02:27

    pretty cool egg cup