EFI Conversion

[allamaabroad]

I'm starting to toy with the idea of doing an EFI conversion on the motor in my bus this winter. The way I see it, I really need to upsize my carbs to 44's, and I don't think I'll ever get the kind of gas mileage I want out of these carbs, and i would love to move to something that'll be much more reliable.

So here's what I'm starting to look at:

For induction, I'm tempted to try some Chinese IDF style throttle bodies. I'm already all set for dual carbs (and the linkage/air cleaner setup is about as nice as it gets), so I do want to do dual throttle bodies as well.

These caught my eye, and it may be that the price is too good to be true, but they also may be totally fine for this application.

https://www.amazon.com/SherryBerg-42IDF-Throttle-B...0f5a4e2f90

These support standard TPS sensors, use standard IDF mounting, include fuel rails, and use standard bosch style injectors.

As far as fueling goes, my bus already runs a return style system with a pump that puts out somewhere around 50-60 psi. Totally overkill for what I have now, but I knew EFI might be in the future. All that I would need to change is the regulator.

For crank trigger, I'd likely get a universal 36-1 trigger wheel and mount it to the crank pulley, using a dial indicator to get it running true, then use a dubshop trigger sensor and mount.

https://www.diyautotune.com/product/6-3-4-36-1-trigger-wheel/

And then for everything else, I found a deal on a microsquirt V3 with a set of 4 smart coils (LS2 style). And at these prices, I may as well pickup a cam sync for sequential spark/fuel.

Just kinda taking a look at this now for fun, but does these seem like a decent combination of parts for an EFI conversion? I'd really like to keep this around $600-$700, and I think these parts could totally pull that off.
_________________
Dennis - 1973 Super Beetle ('16-'21)
Debbie- 1970 Baywindow Bus ('21 - Present)
Tin top camper/adventure bus

2180 TW: CNC Panchitos, Beehives Done Right, Web 163, Ultralight Lifters, 1.3 Rockers, CSP Python, Custom Speeduino EFI Conversion with 40mm Throttle Bodies

Distributors are lame

I have a really hard time leaving things alone...

Innovative and affordable engine management systems and EFI conversions for your Vintage VW
Visit https://debbiesaircooled.com/

[Vee Dub Nut]

[allamaabroad]

Vee Dub Nut: I actually did build that turbo motor and I ran it in my bus for a good 8 months or so on wastegate pressure (8 pounds ish). It was awesome running around town with that motor, but ultimately I chose to switch back to NA for the time being as the gas mileage and reliability were pretty awful on long road trips.

Originally, the turbo motor was meant to go in my super beetle, but when I was finishing up the motor build I got a steal of a deal on a bus and sold my super. The purpose of the super and the bus are very different. So yeah, it was fun and I would love to go boosted again, but I think I really need EFI for a boosted cruiser bus.

As a side note, the sidewinder style header for a turbo set up was awesome for a Beetle engine compartment. My turbo setup for my super was completely hidden and had a full size muffler. I would highly recommend using a sidewinder header if that's the direction you're thinking of going.


As far as EFI goes, I think I might take the gamble on those throttle bodies. With a bit of research, I believe a BMW TPS could be made to fit, so at some point I may order those throttle bodies to take a look at them. If i don't feel like I can make them work or fix them up, I'll just return them.

Mario's crank trigger package seems like a good deal, but I'll need to price out my DIY version to see if it's worth it.

I think I'm also good with starting out on microsquirt. I think I can be happy with full sequential ignition and partial sequential injection for a long time.

As far as budget goes, my budget could potentially be a bit higher since I plan on selling my carbs and current ignition setup, which could recoup $300-$400, but by keeping my spending low, I could convert to EFI for less than $400. I'm a college student, so there's not a ton of money for doing this, so keeping a low budget will really help.
_________________
Dennis - 1973 Super Beetle ('16-'21)
Debbie- 1970 Baywindow Bus ('21 - Present)
Tin top camper/adventure bus

2180 TW: CNC Panchitos, Beehives Done Right, Web 163, Ultralight Lifters, 1.3 Rockers, CSP Python, Custom Speeduino EFI Conversion with 40mm Throttle Bodies

Distributors are lame

I have a really hard time leaving things alone...

Innovative and affordable engine management systems and EFI conversions for your Vintage VW
Visit https://debbiesaircooled.com/

[UK Luke 72]

Batch injection and wasted spark are more than enough for our needs.
I've had those sherry berg itbs. They are pretty shit for all of the reasons mentioned above.
VW Speedshop stuff is top tier.
And if you're shipping a box over the pond you'd be as well slipping their trigger wheel kit in too.

https://vwspeedshop.com/product.php?productid=16774
_________________
2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[Rixr]

im in a similar situation , started a restomod of a 74' bus , planning a 2850cc big bore stroker with aftermarket EFI , was looking at a haltec elite 750 ( one step down from motec ) but this will be 2200 aus ( Australia ) just for the ecu , full wiring harness , relays & fusebox & nothing else ...

But damn those microsquirt ecu is really cheap , tho a bit basic - good if on a budget , be good to see what other ones they do

Have you though about having just one throttle body with TPS ( works out alot cheaper ) keeping the idf manifolds & running a simple intake manifold like the old injected porsche 912/2.0 ??

[Wreck]

I’m on an EFI learning curve and on a budget , using a Speeduino ECU , sequential injection and LS 1 coils . It has no bells and whistles but seems to be operating OK . You do need to be able to research and be able to solder components to the boards etc . But for an ECU that’s under $300AUD I’m happy . The bonus is that it is cheap enough to have a spare ,programmed in the car when touring etc , just in case . Something I couldn’t afford with a name brand ECU. Link,or Ecumaster I think are the cheapest alternative and where I will head if the speeduino for some reason doesn’t do the job.
I used a CB cam sync and a home made trigger wheel and cheap non genuine Toyota cam sensor for the CAS.

The gutted out IDF’s will work and it is not hard to make a bracket to hold a TPS.
Because of the cost of parts in Australia , I went with ITB’s from an Arctic Cat 1000 , bought S/H on eBay , then made shafts so they fit IDF /DRLA manifolds .
A lot of work that I wouldn’t do again . I just get the Chinese ITB’s and sort out the bugs .

[allamaabroad]

[Wreck]

Speeduino doesn’t have coil drivers , I used LS 1 coils ( second hand) that have inbuilt drivers .
Because of the high duration cam I went with TPS based fuel , Andy Whittle on You Tube has some great tutorials on tuner studio , I used his knowledge on the various maps , my TPS starts ,0,1,2,4,6,10,15 etc , the higher up the percentage the bigger the gap in percentage . I also made a custom linkage that is progressive . The first halve throttle on the pedal is only quarter at the throttle bodies . So even with 50mm plates (2600cc engine with 7500 redline) I have good low throttle control .

A mistake I have made is the location of the coils , they are to close to the main wiring loom , I plan to move them to the quarter panels ,out board of the manifolds , away from the loom .because of EMF .

[UK Luke 72]

Ooh the carbon pull rods are nice!
I made a progressive linkage too a while ago but found with the table scaled as per Andy Whittle it wasn't necessary.
_________________
2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[allamaabroad]

I think I’m gonna pull the trigger on these Chinese throttle bodies. If I really don’t like what I see, I can return them. However, I think the issues that I’ve heard about them are solvable with a bit of time spent on them, and I have far more time than I do money.

That brings me to:

What would be the ideal throttle body size for this application?
2176 cc
Fluffed up CNC panchitos
9.5:1
1 5/8 Exhaust
FK8 advanced 3 degrees

Generally driven at altitudes around 4500-6000 feet

From what I’ve read, 38-40 would be ideal, 42 would be good too (depends on who you’re asking) Thoughts?
_________________
Dennis - 1973 Super Beetle ('16-'21)
Debbie- 1970 Baywindow Bus ('21 - Present)
Tin top camper/adventure bus

2180 TW: CNC Panchitos, Beehives Done Right, Web 163, Ultralight Lifters, 1.3 Rockers, CSP Python, Custom Speeduino EFI Conversion with 40mm Throttle Bodies

Distributors are lame

I have a really hard time leaving things alone...

Innovative and affordable engine management systems and EFI conversions for your Vintage VW
Visit https://debbiesaircooled.com/

[UK Luke 72]

36mm supported 160bhp on my 2276
Granted you can go bigger, but you just lose throttle resolution.
Somewhere around 38-40mm would be plenty big enough I would expect without any of the downsides of going too big.
_________________
2276 Beetle build https://www.thesamba.com/vw/forum/viewtopic.php?t=670744&highlight=2276+beetle+daily
2276 EFI Conversion https://www.thesamba.com/vw/forum/viewtopic.php?t=689172

[vwfreek61]

[allamaabroad]

[Vee Dub Nut]

[Vee Dub Nut]

[Vee Dub Nut]

[clonebug]

[Brian_e]

I have the China 42mm throttle bodies on my efi 2333cc in my road trip bus. They took quite a while to get everything dialed in 100%, but they have been working good now.

I found the TPS off of some Land Rover to work. I have the part numbers at home, and I will update this when I get back into town. I ordered 2 and keep one as a spare. It bolted right up with some hardware from Ace.

The CB and various other air cleaner/linkage bases won’t fit. They sit to low and hit the injectors. They would need to be spaced up about 1/2” to make them fit. The bolt pattern on them is also 1/2 hole off everywhere. You will also need to make/buy some linkage arms with the D shape in them, and find a way to attach them to the shafts with a set screw. The throttle stops need to be incorporated into them also. The arms that come with the throttle bodies are almost 100% worthless.
Lots of different ways to try and overcome these issues. I ended up making new tubes with flanges to bolt to the top of the TB’s, and running 4 separate K&N filters slipped over the tubes. I also worked with Pete at SyncLink to make some new pulleys since I was using his linkage previously. He got them pretty darn close going off of texted pictures and my measurements, but they still needed some more tweaking, machining, and fine tuning. If I were to do it again, I would just use the CB throttle bodies and CB linkage. Pay the money the money and bolt it on.

For my ecm, I used microsquirt, added the 2nd MAP sensor, and the rest of the kit is from Mario. I have about 4500miles on it now. I use tuner studio, and the mega log viewer. For the most part it works pretty good, and there are tons of tuning options. Almost to many. Getting it to run right and making the VE tables and timing tables correct for the engine are easy. The start-up enrichment, the warm up cycle, and mostly the altitude compensation have all been a major PITA. I have tried all the way one way, and all the way back the other way, and I can’t seem to get the altitude comp to work. If I were to do it again, I would use a FuelTech 450 from Stef at Ace and be done. More money, but much easier all around.

All in all, I have about $3500 into my swap. 😳. I was in somewhat of a time crunch, so I just ordered the whole kit minus the TB’s from Mario. I didn’t want to spend the time engineering everything and then troubleshooting. I put the kit on, drove it about 100 miles, got the tune close, then loaded up the bus for a 3000 mile road trip.

It ran great on the trip, except I needed to continuously log and update the tune every night for the new altitude changes. It got no better MPG than my decently tuned 44mm IDF’s, power output feels the same, and the throttle response is slightly slower. It also drives me nuts that it takes 2-3 revolutions before it will light and idle. The IDF’s pop off with less than 1 revolution.

All in all....I bought it to try out and test it for possible use on customer bus engines. At this time, I won’t sell it to customers. Too much going on, and it will be over the heads of 90% of typical bus owners. It is also a royal pain in the ass to trouble shoot when you are not in the garage. A magnaspark and some carbs really only have 3-4 possible things that can go wrong, and they are all easily checked with a test light.
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www.type-emotorsports.com

[gorbur]

[slalombuggy]

If the fuel rails have threaded ends for the barbed fittings you can easily change over to AN fittings. My entire FI fuel system is done with AN fittings and steel line although that alone cost me what your budget for you system is. I highly recommend it.