What I think would be a good project would be to measure the resistances of a "good" AFM as you move the rotor, and then use either a modern hot wire AFM unit to measure airflow or a rotary encoder on the original flap and a microcontroller to simulate the resistance value against air flow of the old AFM .
This looks interesting if it works to shift the wiper arm to solid ground https://www.itinerant-air-cooled.com/viewtopic.php?t=7761 I've been doing a lot of reading around the subject whilst I'm paused on the engine rebuild. If I can get the original working....great. the seller said it was working before I bought so fingers crossed. However, playing with my limited knowledge, there is lots of stuff about hot rodding and high rev power gains using existing AFM modules but nothing so far about converting the AFM module from a L-Jetronic to an LH or even a LH- Motronic. As @mikedjames said has anybody ever heard of a successful adaptation?
Interesting video about messing with AFM. Not sure how his bending of the wiper about half way through would actually work...but what do I know!
That's not a bad vid, but I'd avoid soldering the wire on. Nothing wrong with the contact pad as it is. Somehow altering the position of the wiper so that it touches a fresh area of the track (to skip over the "bald" patch) is what you need to do, but that looks pretty fraught. Maybe possible.
It's been a long time since I last posted here. But I've been looking for info on the net where there is a fair bit about FI and what parts do, a lot about fault finding.....never a good sign but I've only just stumbled across this in the back corner of Ratwell's library, a rebuild set of instructions. http://web.archive.org/web/20030422150519/http://web.mit.edu/kaefer/www/1978c.html I've also cleaned up the parts I've got, I've even figured out what some of them do....my wife thinks I'm mad and she is probably right. Anyway, a question for all you good people, I remember speaking to somebody at TE about a source for the vacuum hoses. Was it @Baysearcher ? I can't remember. At the same time does anybody (@davidoft ) have good condition spares? I will be doing some checking of what I need over the next few months , so it is not an immediate need, just casting the net to see what is out there. Thanks
T’wasnt me! If I did though I’d have just said try @davidoft ! I have no idea what sizes you’d need, or how much, but I have a selection of pneumatic hoses available to me if you find out!
@Chrisd Have you contacted FBI VW to see if they have any FI parts removed from buses they have imported from the US?
Cheers Mark, they are a new outlet for me. Gave him a call and he was very helpful, so I'll pull a list together and see if he or our very own @davidoft has stuff.....
That's good to hear, fingers crossed he comes up with some good parts. eBay sometimes comes up with parts too..
@Chrisd That was me at TE germansupply.com do vacuum kits jolly expensive but you know it will be spot on. They also do the 4 manifold to air in take plenum large rubbers and all sorts. James Sent from my iPhone using Tapatalk
I have never quite got round to fitting this.. A K-jet system derived from Beetle, Golf and XR3i parts... What puts me off is the massive fuel distribution valve assembly. It needs a frame built to support it .
So with my idea still gestating in the background to change back to FI from my dual Weber's at some point and Mike's thread (https://thelatebay.com/index.php?threads/crank-timed-ignition-going-back-in-time.98496/page-2); I was wonder what parts of the old system would be improved with modern equivalents @mikedjames, @lhu1281 and others. I think I'm nearly there with the parts and Mike and I at the last TE found that, with a slight adjustment, I have a working AFM with a clean signal and I assume my ECU (California version) works. Would changing these or other modern parts make the old system better? PS I define 'better' as improved reliability and fuel consumption
Something like a MegaSquirt system could drive your injection. However, loading it with the maps/data necessary for your bus engine wouldn't be straightforward. Ideally, you'd need to run the engine up on a dyno and experiment. You'd be unlikely to find a system that just plugs in.
Personally id bin off all the old stuff and replace with a modern ECU , injectors and everything else ... my 914 had nothing of the original FI so i chose microquirt . simple enough to build and uses all modern Bosch wideband and sensors .Everything is new and easily cheaply sourced not relying on old outdated stuff. i used new Mini R53 injectors in motorbike throttle bodies but you can just modernised all the old stuff As for fitting the Mexibug EFI stuff a guy i work with has sourced and fitted it all to his 1600 KarmanGhia , again running microsquirt as you will still need to map your engine to the components .its not a bolt on and play . Every engine is different and would need a map to suit . thedubshop in the US do some real nice stuff but you can source most everthing in the UK
You don`t need a rolling road as microquirt can autotune on a drive with the timing and AFR tables set .. there are plenty of forum out there and getyou going maps etc ..
