Medusa - Page 273
Have an account? Register

Forgot your password?

Forgot your username?

 
Likes Likes:  468
+ Reply to Thread
Page 273 of 326 FirstFirst ... 173 223 263 271 272 273 274 275 283 323 ... LastLast
Results 2,721 to 2,730 of 3256

Thread: Medusa

  1. #2721
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    Well , v i and i set off for Blenheim palace car show this monday , and ,apart from losing each other ,after i roared off down the a40 from witney ,leaving her at the stn , we met up again at the palace ,and waffled into the show ground .(oh by the way , the pressure air feed to the vap did not work.... horrible surging... had to stop and rip it off)

    now ... it may be me and my huge ego , but it seemed to be a bit of a magnet , and even more so when v talked me into the centre arena for a modified cars interview session .

    the poor bloke on the radio microphone ,started counting trumpets out loud, talking to the crowd , then sort of realised it had 2 engines and demanded to find the owner ,he then grilled me for 10m ,and got me a big round of applause and a special plaque too. lots of fun.

    we parked it up ,and according to v i then talked non stop to people for 4 hours .

    tell you what that exhaust silencing has basically been digested , its got a hell of a bark on start up ...as everyone nearby will testify when we went .

    so back home we roared , cruising much better at 60 mph .and brakes now dip the front on application so thats a big driver aid .

    pics..

























    v took these for me , i particularly like the last one .,,looks like its about to bite someone !





    so now to the next part of the development program...



    since i had filled up at the stn until full , i could now drive back and fill it again, AND SEE MY MPH ..



    um ,well this is when i got a little bit of a shock .




    now you might say ,hey ,15 ,20 mpg not too good , but liveable with for short trip here and there on lpg ?




    how about ,


    ready for it ?



    THREE POINT SEVEN SEVEN to the GALLON !!!!!!





    yup thats 3.77 mpg and gee is about right ! costing me 77 pence per mile ,and 20 mile range on a 40 l tank .


    so OBVIOUSLY there is something not quite right in the land of straight 12's , and my next series of steps is devised to sort it out .



    firstly , it oiling down the guides, fouling plugs ,which then misfire ,so a new set of guide seals are needed .

    its not got enough spark , and so i have my friend Andy trying to fix my old msd Alan fried , and also found what may just be an expensive ally box for 25 quid on ebay , but looks like it may be a viable msd6 china knock off, sold as spares or repair .

    next i need to find out how evenly the copper pipes are feeding the cylinders ,and then fit a tap to each feed ,so i can adjust each cylinder separately , my suspicion is that some cylinders are pig rich ,and some lean , so that the end reading looks good , but is, in reality, a sack of pooh.





    so to do this i have hoicked out an old pico thermocouple logger that runs 6 egt probes , and i can read the separate pipe temps ,and adjust till even ...how to fit the lpg taps into the system i have not quite decided ... i really don't want to cut my copper pipes up ....so may try to tap the ally mixer stubs for a cross bolt.



    to understand the internal condition of the engines , i did a compression and a leak down test on all 12 cylinders ..




    the 4.0 was good at 170 psi on all 6 , the 3.6 not so good at 105 to 144 psi on all , however leak down the 3.6 was 10 to 20 % on all cyls, and the 4.0 was 12 % on 3 and 36% on 3 , so i am assuming rusty bores , all the leakage was down the bores not the valves .



    weird the 4.0 would have such good comp but poor leakage , i reckon the oiling down is sealing the rings on that one a bit .


    so that's where i am so far , oh no i forget i did a scan of the timing curves out my home made distributors , oh you will laugh !



    the base setting was 7 d btdc , the 4 litre was getting to 15d total at 3k rpm ,and staying there all the way through ,and 3.6 was getting to 25d total,and staying there ..

    so i wanted bae of 15d and 14d advance and i got 18d centrifugal on the 3.6 and 10d on the 4.0 (after i tested it again at 450 rpm and its base was then 5 ).



    so i will have those apart and file down the stop on the 4 and build it up a bit on the 3.6 ,then put a slightly heavier spring in th 4.0 and a lighter one in the 3.6 .then set base at 15 ,and this should made a bit improvement in economy .


    fun fun FUN .



    regards
    robert.
    Last edited by ivanhoew; 30-08-2018 at 20:27.
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

  2. Remove Advertisements
    RodsnSods.co.uk
    Advertisements
     

  3. #2722
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    distributors are done!


    both on 13d centrifugal ,and 15 degrees static timing ,and vacuum advance working .


    had the MEDUSA MTB( medusa thirsty bee-atch)runnig for a long time in the cave , now the advance is right the vacuum signal to the mixers is higher , so i could wind in the taps a lot , then went for a drive this evening on my ritual pilgrimage to the stn lol.

    well , its definitely a lot lot faster ,now the timing is right , pulls like a beast .

    i worked out, with all the static running and so on , on the way to the stn it got around 5 mpg , so its getting a bit better . had her up to 66 ish on the way back in the dusk , it was fun ,the lights are good .

    brakes are so much better with the higher vacuum from the timing too.


    one test i did was to tie some old thermocouples onto 4 headers ,cos i only have 4 sensors, and plug them into a logger to see if it would show interesting data ..


    came up with this ..






    those are the external temperature traces of 4 pipes on the 4.0 litre . 2 of the traces were from 10 inch long probes ,and you can see what happened halfway through when i pulled them into a different position so just the tips were on the pipes ...much higher readings .


    the upshot of this is that it looks like a valid way to compare cylinders if i can get 6 thermocouples all the same .



    geektastic !




    regards
    robert.
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

  4. #2723
    Administrator blackpopracing's Avatar
    Join Date
    Apr 2009
    Location
    Slough
    Posts
    8,713
    Images
    1754
    Post Thanks / Like
    blackpopracing is offline
    Look at you with all your magic things!

    Heretic!! burn him!! burn him!!!

  5. Remove Advertisements
    RodsnSods.co.uk
    Advertisements
     

  6. #2724
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    Muuuahahahaaahhaa !!!!
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

  7. #2725
    Rods 'n' Sods Junkie Andy650's Avatar
    Join Date
    Oct 2013
    Location
    Eastleigh
    Posts
    108
    Images
    16
    Post Thanks / Like
    Andy650 is online now
    Loving this thread. Love the way you tackle problems & come up with solutions.
    Re the dyno. I notice you have the extraction tubes sealed to the exhaust pipes. does the exhaust extraction have suction fans? My thoughts are if they are not strong enough it will cause back pressure. However if they are too strong they will have a scavenging effect & affect the dyno readings. Also not really knowing about dyno testing myself this could all be nonsense. Keep up the good work old chap. pip pip

  8. #2726
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    thank you Andy

    re dyno , there is a powerful suction fan , but the flexi's are much bigger than the cars pipes ,so no suction ,just sucks in the room air as well as the fumes ..this get passed through a concrete bunker full of aerated coal .
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

  9. #2727
    Official RnS Addict
    Join Date
    Nov 2010
    Location
    Bedford
    Posts
    1,798
    Images
    1149
    Post Thanks / Like
    Flying Phil is offline
    Great that you are out and about! Very glad that your efforts are being appreciated by a more general audience. ........and many thanks for your regular thread updates/humour/candour and insights.

  10. #2728
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    Quote Originally Posted by Flying Phil View Post
    Great that you are out and about! Very glad that your efforts are being appreciated by a more general audience. ........and many thanks for your regular thread updates/humour/candour and insights.
    thank you Phil much appreciatedado !


    new medvid

    https://youtu.be/g_dVkDq9-4A
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

  11. #2729
    Rods 'n' Sods Junkie
    Join Date
    Apr 2018
    Location
    Uk Hampshire
    Posts
    142
    Images
    0
    Post Thanks / Like
    stevesteve is offline
    Just enjoyed watching your video, found it interesting. I'm wondering that your are not supplying the LPG from the vaporiser to the engine in a correct manner with your individual copper pipes. What make LPG system are you using and how is the quantity of gas supplied from the vaporiser? I may have it wrong but, is manifold depression not monitored via a venturi at the inlet manifold throttle butterfly and acts on a vaporiser diaphragm via a hose?
    Incorrect mixture is highlighted by the spark voltages as you point out so maybe looking at the fuel supply next. Fascinating build really enjoying your work
    Last edited by stevesteve; 10-09-2018 at 17:12.

  12. #2730
    Official RnS Addict ivanhoew's Avatar
    Join Date
    Feb 2013
    Location
    uranus
    Posts
    2,103
    Images
    3
    Post Thanks / Like
    ivanhoew is offline
    Quote Originally Posted by stevesteve View Post
    Just enjoyed watching your video, found it interesting. I'm wondering that your are not supplying the LPG from the vaporiser to the engine in a correct manner with your individual copper pipes. What make LPG system are you using and how is the quantity of gas supplied from the vaporiser? I may have it wrong but, is manifold depression not monitored via a venturi at the inlet manifold throttle butterfly and acts on a vaporiser diaphragm via a hose?
    Incorrect mixture is highlighted by the spark voltages as you point out so maybe looking at the fuel supply next. Fascinating build really enjoying your work
    Wonder no more steve , i am definately not supplying it in the normal manner , the system is all my own cobbled together arrangement . the vaps are omvl r90's.

    yes the fuel supply ,and finding a way to insert taps into each seperate cylinder feed is next on the agenda .
    Bicester scramble ,Medusa enjoyed the trip.https://www.youtube.com/watch?v=Q-7I7-nA19U

+ Reply to Thread
Page 273 of 326 FirstFirst ... 173 223 263 271 272 273 274 275 283 323 ... LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Where you live, Town\City\County etc.

Please enter your full name
This field cannot be edited once it has been completed other than via contacting the site admin. Please make sure the information is correct first time.

Log-in

Thread Information

Users Browsing this Thread

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

    Similar Threads

    1. Medusa guitar
      By evilzee28 in forum Chat
      Replies: 8
      Last Post: 19-03-2013, 12:58

    Bookmarks

    Posting Permissions

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