Stock type 4 1800 EFI conversion diary

[Wally]

In addition and as a follow-up to this thread:
https://www.shoptalkforums.com/viewtopic.php?t=152962

In my search for a relatively simple solution to EFI a carburated stock type 4 engine, I thought this community might enjoy it when I kept a diary of the progress. And its always fun to share, so here we go! )even if updates might take a while sometimes)

Just to be clear up front: I sell nothing and just use what I see best fit for the job or whats easiest for me to get hold of. Mind you I am located in Europe.
That said, Paul from vwspeedshop.co.uk helped me get going in selling me his prototype set-up for a type 4 EFI conversion. Should be on its way as we speak

The idea is to firstly get a baseline (dyno) from a stock engine in original carburated form, then convert it and dyno it again.

For now there is some work to be done to the engine before it can be run as is.
Its an 412 'N' (set-up for Normal or regular gasoline) engine. Engine code AT. In Europe this meant a 1800 unit with 75 hp as stock and two Solex 36-40 PDSIT carbs with 29mm chokes.

A slight downside to these engines is the 210mm clutch unit as 210mm is an oddball size and the original VW412 spline is smaller then all other regular type 1 or type 2 (bus) engines and transmissions...
But, low and behold, a german buddy knew that VW Golf (Rabbit) engine had the same spline as type 1 and 2 and they were also 210mm!
Funny thing is: those disks are very cheap as a bonus!
So, here is the engine in question with its new clutch disk in place:



The engine will ride in my buggy, where the stock type 4 cooling will not be a issue

[Bruce.m]

great, look forward to the updates

[raygreenwood]

Great looking build!
By the way Wally...the early type 4 bay bus of 1972 used a large/standard spline 210mm clutch instead of the 411/412 spline.

It was only the 1.8L engines that got the 215mm clutch. Yes, the 411/412 had the same small diameter spline for its 1.8L 215mm discs but the 75/76 bus also had the 215mm clutch and had the larger standard size spline. shaft.

Also, a 210mm flywheel can be used with a 215mm clutch and PP. I use this combination on my 412. You will find that the friction surface in the 210 flywheel will easily accomodate a 215mm disc with no machine work. If you look carefully, the sides of the ledge in the flywheel slope outwards.

All you need to do is enlarge the chamfer around the opening to slip the 215mm disc in at a slight angle. Then enlarge the holes in the PP so they work with yoru 8mm bolts and you are done.

Ray

[Wally]

Great looking build!
By the way Wally...the early type 4 bay bus of 1972 used a large/standard spline 210mm clutch instead of the 411/412 spline.

Thanks Ray!
Yes, I knew the T2 busses with thye early type 4 engines also used 210mm, however... 210mm disks with the large/standard spline can NOT be obtained anymore.. at least not in this part of the world. CSP has none and also our local Dutch supplier (Paruzzi) does not have these on their parts list anymore.
Of course, otherwise I would have easily bought a VW T2 210mm disk, right?

It was only the 1.8L engines that got the 215mm clutch.

Well, I know you have vast knowledge about type 4's Ray, but sorry, I will need to correct you on this: I have here two ORIGINAL stock 412 1800 engines, one AT coded engine (the above, stock 75hp) and an AN unit (stock 85hp through more CR). These were the only two engines that were delivered in Western Europe for the '74 model year VW412.
BOTH these engines have a 210mm flywheel..
It is very well possible that VW also supplied 215mm flywheels with the 1800 412 cars as it was the last year and VW often mixed up parts as we know, but your generic suggestion that the 1800 412 engines ONLY got 215mm flywheels, cannot stand with what I saw on these engines.

Also, a 210mm flywheel can be used with a 215mm clutch and PP. I use this combination on my 412. You will find that the friction surface in the 210 flywheel will easily accomodate a 215mm disc with no machine work.

No machine work?

All you need to do is enlarge the chamfer around the opening to slip the 215mm disc in at a slight angle.

That sounds like machine work But yeah, I noticed the chamfer as well. As is, a 215mm disk won't pass this chamfer and will not reach the FW surface..
Plus you would need to resurface the flywheel so the whole 215mm lies flat and not ride the edge of the old 210mm plate. More machine work.
Then you would need to balance the whole thing again, which is of course... even more machine work

I really tried to solve the as simple as possible to stay in the realm of this project: simple and cost effective, hence the Rabbit 210mm disk for almost 1/3 of the cost of a 215mm VW disk sold by our familiar classic VW warehouses...

Anyhow, just reasealed the leaking pushrod tubes in the way I know works always for me (with Hylomar sealant around the O-rings and throw away the pesky wire spring) and retorqued the heads which was also really neccesary as I could turn the nuts about 90 degrees more before original head stud torque was reached! (damn original head seals).
If you know these engines a bit, you also realize you just cannot use them 'as is' and expecting no leaks...
Next time I'll post a picture again

[Paul H]

It is indeed on the way
I may have an original T4 fuel injection intake with the throttle body converted to a TPS and stainless fuel rails

[raygreenwood]

Great looking build!
By the way Wally...the early type 4 bay bus of 1972 used a large/standard spline 210mm clutch instead of the 411/412 spline.

Thanks Ray!
Yes, I knew the T2 busses with thye early type 4 engines also used 210mm, however... 210mm disks with the large/standard spline can NOT be obtained anymore.. at least not in this part of the world. CSP has none and also our local Dutch supplier (Paruzzi) does not have these on their parts list anymore.
Of course, otherwise I would have easily bought a VW T2 210mm disk, right?

It was only the 1.8L engines that got the 215mm clutch.

Well, I know you have vast knowledge about type 4's Ray, but sorry, I will need to correct you on this: I have here two ORIGINAL stock 412 1800 engines, one AT coded engine (the above, stock 75hp) and an AN unit (stock 85hp through more CR). These were the only two engines that were delivered in Western Europe for the '74 model year VW412.
BOTH these engines have a 210mm flywheel..
It is very well possible that VW also supplied 215mm flywheels with the 1800 412 cars as it was the last year and VW often mixed up parts as we know, but your generic suggestion that the 1800 412 engines ONLY got 215mm flywheels, cannot stand with what I saw on these engines.

Also, a 210mm flywheel can be used with a 215mm clutch and PP. I use this combination on my 412. You will find that the friction surface in the 210 flywheel will easily accomodate a 215mm disc with no machine work.

No machine work?

All you need to do is enlarge the chamfer around the opening to slip the 215mm disc in at a slight angle.

That sounds like machine work But yeah, I noticed the chamfer as well. As is, a 215mm disk won't pass this chamfer and will not reach the FW surface..
Plus you would need to resurface the flywheel so the whole 215mm lies flat and not ride the edge of the old 210mm plate. More machine work.
Then you would need to balance the whole thing again, which is of course... even more machine work

I really tried to solve the as simple as possible to stay in the realm of this project: simple and cost effective, hence the Rabbit 210mm disk for almost 1/3 of the cost of a 215mm VW disk sold by our familiar classic VW warehouses...



Anyhow, just reasealed the leaking pushrod tubes in the way I know works always for me (with Hylomar sealant around the O-rings and throw away the pesky wire spring) and retorqued the heads which was also really neccesary as I could turn the nuts about 90 degrees more before original head stud torque was reached! (damn original head seals).
If you know these engines a bit, you also realize you just cannot use them 'as is' and expecting no leaks...
Next time I'll post a picture again

Yep no doubt!...some of the many differences we have collectively found over the years in how these cars were outfitted between Europe and the US markets vs gray market cars etc.

Over here, I have seen (and been under the hood of) a grand total of four 1974 412's that had the 004 four speed. All of them were 1.8L. All of them also came out of Canada and none of them were two door coupes! All of them had 215mm flywheel. Oddly...counter to things we read, they were all L-jet.

I have been under the hoods of quite a few two door coupes (in the US)...a few more come out of the woodwork every few years...all with 1.7L and D-jet...all with 210mm flywheel.

Supposedly (according to VW literature), two door coupes all came with manual trans and D-jet. I have never seen a two door with automatic so I believe that, but they were not actually offered here. Every one of them including the one I own was imported as gray market or tourist vehicle.

Also in the US, the 004 manual was not offered in anything by dealers either four door or wagon, but was available in Canada and tourist delivery trim.

As far as machine work for the flywheel....unless your disc has actually worn an outer groove in your 210 flywheel....it does not need to be resurfaced larger. Its already large enough for the 215 on the friction surface. I have also gotten my 215 discs to tip in at an angle with slight pressure with no added chamfering....BUT....not every flywheel has just the right amount of space. I have two 210 flywheels whose opening is just too tight without added chamfer so check what you have.

Question ,is your large spline 215 disc a "spring" disc? If so...I understand. If it was solid I was going to suggest just having it rebuilt if you still have clutch shops in your area.
Ray

[Wally]

Anyways, engine is in, so I could fiddle somewhat with installing ancillaries and to have a templet for restoring primaries made from old 412 heat exchangers. The heat old exchangers were from another engine and were pretty rusted at the connextion side with the silencer.

The heads needed a few new exhaust studs and so did the Leistritz (OEM) silencer.. New flanges, 1some 38mm 304 tubing from CSP and some welding later, it all sits where it should be without buying new expensive parts. Its mostly (apart from the air filters) stock, so no need for anything bigger or fancy.







Only one fuel pump nozzle doesn't stay seated, so I need to adress that next, then test drive and make a dyno appointment (the fun part),

[Wally]

And she runs now pretty decent for just setting valve lash and timing!
The floading on one side was just caused by a float that needed some ‘adjusting’ (bending the tab a little). After that the fuel stayed in fine
Luckily I have some carb fixing abilities left

[Wally]

As promised and well, after the weather got a little better, I drove to the dyno last WE and made a few runs.
The only non-stock part were the K&N air filters as the original one got in the way with how I liked to mount the coil in the buggy (center of the block).
Result was a terrible juttering and generally way too lean, so we replaced the stock 132,5 main jets with a set of 137,5 ones, but up top it was still way too lean (AFR > 1,2).
The original stock distributor seemed not wanting to provide a good strong spark under load, despite new points, so I installted my old 123 dizzy.
After that the engine ran a million times better and yielded a nice flat torque curve: 67hp. The too lean condition up top costet some hp, but further jetting tuning was not what I was in the mood for (like ever)

short vid of the quick run:


and the resulting boring dyno sheet:


So, I have a base line now

[Bruce.m]

Looking forward to the journey

[Ephry73]

Progress and base lining is what it’s all about.


Sent from my iPhone using Tapatalk

[K70]

Hi,
Nice to see European buggies!
Confirmed what I thought. Vw like to jet lean in type 4 or type 1.
More dyno testing please!
Especially with different exhausts options.