Building an extractor for C2J(R5 ts) engine in R8
  • Register
  • Help
Results 1 to 19 of 19
Like Tree11Likes
  • 5 Post By Frans
  • 2 Post By potentz
  • 1 Post By Thierry
  • 3 Post By Frans

Thread: Building an extractor for C2J(R5 ts) engine in R8

  1. #1
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default Building an extractor for C2J(R5 ts) engine in R8

    I thought I should build an extractor to go with my planned ITB inlet.

    I have a pair of extractors from Opel(Vauxhall) with 2,0L XE engine that I though would be good for parts.
    Building an extractor for C2J(R5 ts) engine in R8-dsc_0234.jpg

    The question is wether to just make up a new flange and modify one of them as mutch as needed to fit the engine and the car. Or just look at them as pipes, bends and collectors and try to build it as close to ideal as possible.

    The primaries are 36x1,5(33mm ID) about 33-36cm long. Secondaries are 41x1,5mm(38mm ID) that is about 40cm long. Far from ideal but still far better than what is bolted to the engine originally. The inner ports is of course too far from each other. The outer a bit too close.
    Building an extractor for C2J(R5 ts) engine in R8-dsc_0235.jpg
    Building an extractor for C2J(R5 ts) engine in R8-dsc_0236.jpgBuilding an extractor for C2J(R5 ts) engine in R8-dsc_0237.jpgBuilding an extractor for C2J(R5 ts) engine in R8-dsc_0223.jpg

    I havent done any calculations myself but I see the what is usually suggested for a 4-2-1 for similar engines is about 60cm primaries and 30cm secondaries.

    Any thoughts?

    Advertisement

  2. #2
    1000+ Posts Frans's Avatar
    Join Date
    Sep 2001
    Location
    Auckland
    Posts
    1,293

    Default

    Hi Reidar,

    I have a love for extractors and some experience of the effectiveness of a correctly calculated one. There are a few horsepower locked away in it. The advantage of having a good calculated extractor is that you can have a very hot cam in the car with matched carburators and it will be almost as driveable as a car without a hot cam. I can prove this and take a look at my last post in "2 new racecars in NZ" then you will see how driveable my race car is with a wild cam and good extractors. An AFer on here has followed my Spreadsheet and I hope he sees this and could maybe confirm his experience as well.

    I have an Excel Spreadsheet that I made to do this calculation because it is about 2 or 3 pages of calculations if you do it by hand. What I am trying to say as well is that if you are going through with the trouble of making one, then you might as well do it the right way. The calculation takes into consideration the exhaust lobe position on the cam the rpms where you would want it to work to it's optimum, the speed of sound etc..

    This formula dates back to the 90's when I worked the formula into the spreadsheet. It is one from a race engine builder in USA with hundreds of hours on the Dyno to prove the results.There might be other ideas by now and it is for a 4 into 1 only.

    I will help with the spreadsheet if you want. Here are a few pictures of the race car extractors that I built at home by buying bends and welding them together to get the correct lengths.







    This is for a crossflow G head but it will look the same for your head and I see you have the good type head.

    Regards, Frans
    JoBo, ReidarUF, PeterT and 2 others like this.
    Old enough to know better
    Young enough to do it anyway.

  3. #3
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    Hi Frans.
    I've studied your extractor and also the calculations for it from the spreadsheet. I thought it might build something similar for another engine based on R5 Alpine witch I have a pretty hot camshaft for.

    The C2J are probably not going to be that hot but it would still be fun to dial in the numbers in your spreadsheet to see how it turns out.
    I'm not too keen on putting four metres of primaries in the back so I would prefer a 4-2-1. Is your spreadsheet usable for that? I remember Ross building a really nice one for his Dauphine.
    Last edited by ReidarUF; 7th March 2018 at 09:22 AM.

  4. #4
    Fellow Frogger! potentz's Avatar
    Join Date
    Jul 2011
    Location
    adelaide australia
    Posts
    295

    Default tuned length extractors

    yes,i used Frans calcs for my 4 into 1 setup.really works well throughout the rev range.good idle and drivability is great.
    highly recommend this .
    Attached Thumbnails Attached Thumbnails Building an extractor for C2J(R5 ts) engine in R8-20150218_193521.jpg   Building an extractor for C2J(R5 ts) engine in R8-20150217_143126.jpg  
    ReidarUF and bowie like this.

  5. #5
    Tadpole Thierry's Avatar
    Join Date
    Feb 2015
    Location
    Central coast
    Posts
    28

    Default Building an extractor for C2J(R5 ts) engine in R8

    Thanks for sharing, Im going to be dreaming about extractors tonight, would love to be able to make a set .


    Sent from my iPhone using aussiefrogs
    bowie likes this.

  6. #6
    Fellow Frogger!
    Join Date
    Dec 2010
    Location
    Blackburn Victoria
    Posts
    417

    Default

    All good to make your own, but you know you can buy a set off the shelf from Mecaparts??
    (R5 in R8 or A110)

  7. #7
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    Mecaparts dont have extractors for my engine. Actually I havent been able to find extractors for C2J engine in R8, only for R9/11.

    When speaking of Mecaparts and Autobleu who produce their extractors they have many designs from short 4-2-1 similar to my two opel/vauxhall ones to quite long 4-1. Their 4-1 still seem quite a lot shorter than those built after Frans calculations. A compromise I guess.

    Arne Berg is a well known(in Scandinavia and Finland) Renault tuner in SWeeden. Some time ago I got a drawing of his extractor design.
    Building an extractor for C2J(R5 ts) engine in R8-102_2220-2-.jpg
    A 4-1 with primaries similar to those on my Opel 4-2-1...
    Last edited by ReidarUF; 7th March 2018 at 08:40 PM.

  8. #8
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    I just got Frans spreadsheet. I put in the data and came up with this:
    Building an extractor for C2J(R5 ts) engine in R8-screenshot_20180307-104217.jpg

    I think I Will have flanges cut at the local mechanic scool to save some work. Will probably have two or more cut in case I'll try different designs.

  9. #9
    1000+ Posts PeterT's Avatar
    Join Date
    Jul 2000
    Location
    Castle Hill, Sydney
    Posts
    7,214

    Default

    I'd be interested to hear how it compares with this online calculator, which is based on the formulas in Graham Bell's book.

    Exhaust Calculator - Time in the Garage

    '92 205 Mi16
    '90 Mi16x4

  10. #10
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    I gave it a go:
    Building an extractor for C2J(R5 ts) engine in R8-screenshot_20180307-133559.jpg
    Building an extractor for C2J(R5 ts) engine in R8-screenshot_20180307-133607.jpg

    Seems strange to me. For a 4-2-1 it calculates 37" primaries but on 4-1 it simply states they should always be 15". Did I get this all wrong?
    Last edited by ReidarUF; 8th March 2018 at 01:04 AM.

  11. #11
    Fellow Frogger! R8philSA's Avatar
    Join Date
    Feb 2012
    Location
    Vista SA
    Posts
    940

    Default Exhaust calculations ?

    So Guys, where does this leave me??
    A 16TS 1655cc engine sporting 2 x 45mm Side drafts, a cam and light head job.
    I'm wondering if the extractors that came with it are no good???

    Attachment 104301

    Any comments would be appreciated.
    Cheers
    Phil


    Quote Originally Posted by PeterT View Post
    I'd be interested to hear how it compares with this online calculator, which is based on the formulas in Graham Bell's book.

    Exhaust Calculator - Time in the Garage

  12. #12
    1000+ Posts
    Join Date
    Mar 2004
    Location
    Brisbane
    Posts
    1,336

    Default

    A of of us will be interested, love to make a good set too for a hotted up cam.
    87 S1 205 GTI / GTI6 powered a project underway

  13. #13
    1000+ Posts PeterT's Avatar
    Join Date
    Jul 2000
    Location
    Castle Hill, Sydney
    Posts
    7,214

    Default

    Quote Originally Posted by ReidarUF View Post
    I gave it a go:
    Click image for larger version. 

Name:	Screenshot_20180307-133559.jpg 
Views:	36 
Size:	83.3 KB 
ID:	104295
    Click image for larger version. 

Name:	Screenshot_20180307-133607.jpg 
Views:	33 
Size:	85.7 KB 
ID:	104296

    Seems strange to me. For a 4-2-1 it calculates 37" primaries but on 4-1 it simply states they should always be 15". Did I get this all wrong?
    Sorry, I haven't had a chance to get back to this. Attached is the diagram from the book. In the case of a 4-2-1, P1 should always equal 15". ie P = P1 + P2

    Thus both got 1.24" and 37" or 37.12" primaries, for a 4-1. I doubt you'd pick the difference. Looks identical to me.
    Attached Thumbnails Attached Thumbnails Building an extractor for C2J(R5 ts) engine in R8-expipe.jpg  
    Last edited by PeterT; 8th March 2018 at 07:23 PM.

    '92 205 Mi16
    '90 Mi16x4

  14. #14
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    Yes that seems more reasonable.
    So for the 4-1 the the dimmensions are pretty mutch the same as with Frans spreadsheet.

    According to Fiat guru Guy Croft the old rule about short primaries and long secondaries on a 4-2-1 is out dated. That the results are better the other way around.

  15. #15
    1000+ Posts alan moore's Avatar
    Join Date
    Oct 2001
    Location
    Ipswich, Queensland.
    Posts
    1,798

    Default

    Quote Originally Posted by R8philSA View Post
    So Guys, where does this leave me??
    A 16TS 1655cc engine sporting 2 x 45mm Side drafts, a cam and light head job.
    I'm wondering if the extractors that came with it are no good???

    Attachment 104301

    Any comments would be appreciated.
    Cheers
    Phil
    Given the modification the previous owner has done to your R8, I doubt the pipes are too far wrong. Looking at the pics they look to be about 1.5" and 36" or so long. All will be fine. With a reasonable cam and compression it should make 115 Hp at the wheels at a bit over 7K.
    '56 Renault 750 (16TS Power)
    '62 Renault Dauphine Gordini
    '89 Renault Alpine GTA V6 Turbo
    '08 Renault Megane sedan

  16. #16
    Member
    Join Date
    Nov 2011
    Location
    Norway
    Posts
    33

    Default

    @Potenz: I just realised you had the same engine(or head) as me. Whats other mods have you done?

    I made up a drawing today to bring to the local mechanic school to have them make up two or three flanges. Where inlet and exhaust share the bolts i will leave the material till after welding.
    Off cource they would prefer a cad file...
    Building an extractor for C2J(R5 ts) engine in R8-dsc_0247.jpg
    Last edited by ReidarUF; 9th March 2018 at 10:11 PM.

  17. #17
    Fellow Frogger! R8philSA's Avatar
    Join Date
    Feb 2012
    Location
    Vista SA
    Posts
    940

    Default

    Thanks Alan.
    Wow!! that will be interesting, 7K !! Hmm, might be a while before I try those revs on a recon engine. Hope to run it it for a few months before trying the power. Poor little late model R10 gearbox !! best take it easy I guess.

    Cheers
    Phil


    Quote Originally Posted by alan moore View Post
    Given the modification the previous owner has done to your R8, I doubt the pipes are too far wrong. Looking at the pics they look to be about 1.5" and 36" or so long. All will be fine. With a reasonable cam and compression it should make 115 Hp at the wheels at a bit over 7K.

  18. #18
    1000+ Posts Frans's Avatar
    Join Date
    Sep 2001
    Location
    Auckland
    Posts
    1,293

    Default

    Phil,

    Run it in on the track!! Get it fit quickly. Coaches don't take it easy on players.

    Frans.
    FIVEDOOR, bowie and potentz like this.
    Old enough to know better
    Young enough to do it anyway.

  19. #19
    Fellow Frogger! R8philSA's Avatar
    Join Date
    Feb 2012
    Location
    Vista SA
    Posts
    940

    Default

    No way Frans. I need to have some fun in this baby before I cane it and probably blow it up Ha ha ha Phil



    Quote Originally Posted by Frans View Post
    Phil,

    Run it in on the track!! Get it fit quickly. Coaches don't take it easy on players.

    Frans.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •