Author Topic: Front-Mid Engined Opel Manta A-Series Project  (Read 23978 times)

Offline young_un1

  • Jr. Member
  • **
  • Posts: 31
  • BHP: 2
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #15 on: March 09, 2008, 05:10:40 pm »
I should add that there doesn't appear to be any power supply when the ignition and vems is fired up initially either... Looks like it's time to check every inch of the wiring again.

I assume that there's nothing else to set up in megatune other than the req'd fuelling time? (that's been done)

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #16 on: March 09, 2008, 06:52:15 pm »
There should be a good +12v reading across the injectors from the power feed. This will drop to zero when the VEMS grounds the injector (but with a 10ms pulse you'll be lucky to see it).
Check that the relays are functioning correctly and that the fuses are all in place, when the main relay clicks on the power feeds should all come live.

As for setup we may need to sort out the outputs for the fans, fuel pumps etc but now you have crank and spark everything will follow in good order.

Offline young_un1

  • Jr. Member
  • **
  • Posts: 31
  • BHP: 2
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #17 on: March 09, 2008, 11:15:18 pm »
Cheers Rob ;D ;D ;D Had my first burble out of the engine tonight! I suspect it may be down to fueling issues but it ran fine, if somewhat rich!!!, if i put some fuel directly into the intake manifold. It wasn't firing on its own so I thought I'd give it a hand. Obviously the engine was therefore running naturally aspirated and hence it wasn't exactly pretty but so long as it had fuel it was ticking over quite nicely! Managed to get the injectors clicking so i assume they're operating. Maybe just not quite correctly. My current suspicion may be fuel pressure but I plan to check that out tomorrow. Maybe the injectors need a longer time open at cranking?! Hmm... Battery's on charge anyway to ensure that I have a good strong spark for tomorrow's tinkering:)

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #18 on: March 10, 2008, 09:57:32 am »
Stuff, you're now in a position to try my 'rule of thumb' fuelling idea:
http://www.vems.co.uk/forum/index.php?topic=329.msg4391#msg4391

req_fuel = 6.49 * (D / N / I)
D engine displacement (cc)
N number of injectors (eg. 4 for a 4 cyl port injection)
I injector flowrate (cc/min)


Then in priming cranking afterstart for Cold cranking PW we use: req_fuel x 3
and for Warm cranking PW use req_fuel x 0.7

Offline young_un1

  • Jr. Member
  • **
  • Posts: 31
  • BHP: 2
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #19 on: March 10, 2008, 01:21:22 pm »
WOOOO HOOOO ;D ;D ;D It fired up with minimal fuss! Idles quite nicely at about 950rpm too:) My concern now, however, is that there's a fair bit of white smoke coming out when it rises through the revs - is it just me or is a turbo rebuild on the way... Damn. I was told that it was rebuilt too which is even more annoying...strange, as there's no play in the shaft. Now comes the fun of further mapping / putting the lambda back in etc. At least it works though, albeit a bit rough!
Cheers for the help thus far from everyone:)

Offline hilly

  • Jr. Member
  • **
  • Posts: 53
  • BHP: 6
Re: Front-Mid Engined Opel Manta A-Series Project
« Reply #20 on: March 10, 2008, 03:10:29 pm »
I found my Audi V8 smoked a bit when first started up after having sat around for about 1 year.
Revving with no load or idling doesn't pass much air through the engine so any oil lying about in the engine will take a while to burn off.

Once the thing had run for a while it stopped and has not been a problem since.

Hilly