Sean's Mild Type 4 2056cc Build

[Air Cooleds Only]

For your entertainment.... I bring you the journey of Sean's 77 Riviera Camper. Equipped with an 091 Transaxle & 1.8L Engine.

Sean has owned this gem since April 2014. It was purchased in Boise, Idaho; immediately driven down to Prescott, Arizona. After the 24 hour road trip, the bus decided not to start.... Let the problems begin.

I met Sean right before the Jerome Jamboree. He was having problems finding a starter for his bus. After a couple failed attempts with used starters we found a rebuilt unit that worked just fine. Once running the engine had a prominent flat spot with the infamous weber progressive. I helped him get the jetting a little more dialed in so he and his family could get up the hill to Jerome.

After the Jerome Jamboree, Sean still bitched and moaned that his Bus still had some running issues Hmmmm, I asked the usual questions, have the valves been done , dwell , timing etc. We got to compression and he remembered that one cylinder was lower than the rest. I double checked Compression, 105,105,104,95. Not terrible, but definitely on the low end of the range. To boot their were a number of oil leaks.. O and did I mention the lower engine studs were to short to get a nut on.

So Engine comes out & the questions start flyin... Should we just fix the obvious, should we do just the top end, or how about the whole damn thing???

If you read the Subject line...There's a good chance you know the answer to the previous question.

Before you read on. My knowledge of type 4's is not vast. Especially when it comes to turning up the performance level. I have built quite a few type 1 engines, in many different formats, this will be my first T4. Most likley I will have a few questions along the way , and would enjoy constructive input from our fellow samba members.

We have about $3k for parts to front this engine build, and have decided to try and build a 2056cc 71x96. I'm supplying the crank and rod cores from a 2.0 lying around the shop. Cam- undecided, something great for a camper , AA Biral 96mm P&C's, AMC 1.8 Heads, Dual Decade 40mm Carbs.

So here we currently are. With a torn down 1.8L.

Since the majority of the internals are going to be put aside , all we are concerned about at the present is the case. After a good cleaning, first thing I noticed was one of the lifter bores was scarred up from some junk in the oil most likely.

I have a 914 case that I was willing to give up for the build , unfortunately it has an obvious issue as well.
The most common bolt that gets missed on the type 4 is the bolt that holds the oil pick up in place. That is the case with this case . Someone missed that bolt and had a few good whacks with a hammer most likely, until realizing there was a forgotten soldier.

P/O of this case proceded to install a long threaded helicoil. I feel that this fix will be sufficient for our rebuild . What are your thoughts?

Sean & I look forward to continuing with this build and sharing the process.

Chris
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Air Cooleds Only

[theKbStockpiler]

-Inspect the heads to see if they are rebuildable.

- Stay with 94mm cylinders for a heavy vehicle.

-If you want to spend some money get a 76-78mm stroker kit.

-Contact a machinist and ask which if either of the cases is practical to fix.
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My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask.

[Ian]

Always use new heads with any Type 4...the valve seats love to come loose on old heads. I recommend having the exhaust guides reamed on the new AMC heads. The valves like to get hot and seize to the guides. I have Painter's ream em out before installing.

Do you have the Wilson rebuild book? It has a lot of info on everything Type 4 (they had these things in the 80's ). He says "type 4 cases can be welded, welded, and welded again. which is a good thing". Yes, that boss can be fixed, but I would not risk it. It's one thing to weld it and put it in the shop race car, it's another thing to weld it and put it in a customer's Bus.... That helicoil is funny to say the least.

Do you have any of the original injection parts? I'm guessing maybe not because it had a 1.8L in there?? (2.0L from 75 up) The FI is far superior to any carbs you can put on a type 4 and worth finding a complete setup. FI and stock cam are the only way to roll IMO.

Engine work is all about details and any shortcuts will come back to haunt you.
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All your Buses are belong to us.
Love and good roads!
IN LOVING MEMORY OF ROB CRESS 1968-2012

[Clatter]

The lower case bolt damage you have shown is known officially as "The Syndrome".

This is caused by someone over-tightening the oil strainer bolt at change time.

It would require some serious welding/machining skill to rectify.
No, a long helicoil is not a sufficient fix...

The best cams/kits come from the type 4 store.
A web 73 or 86 can be an economical choice if you are an a low budget.

Ditto on dished 94s.
96 AA Birals would be a fun, if somewhat short-term experiment.

42 x 36 valves are a good way to gain power, not making the cylinders thinner.

You will need a better exhaust if you are going to up the power, also.
72-74 spec.

Welcome to possibly the hardest aircooled VW environment to work with - Type 4 in a bus.

Best do some homework if you want to keep a good reputation in your area.
This is NOT an easy application to have any long-term success.

Good Reading:

http://shoptalkforums.com/viewforum.php?f=1&sid=a0fc7ac8acde1eac85e0cdda5ab9ab4f
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Bus Motor Build

What’s That Noise?!?

[GTV]

Some good (and recent) info here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=609633

The consensus is the best way to increased displacement on a bus engine is through stroke. Stock 94 bore (dished), 78 crank with type one rods seems to be the most conservative and logical approach. 2165cc.
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EMPI Power Rules!

[Bad bug]

[Air Cooleds Only]

[Air Cooleds Only]

[GTV]

I thought part of the issues with 96's is the flat top piston, resulting in a compression ratio that's too high? Is it possible to machine a dish in the piston deep enough to correct this?
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EMPI Power Rules!

[Clatter]

[GTV]

[theKbStockpiler]

The 2.0 type IV is a 1.8 engine the factory put a stroker kit in. The crank journals are smaller so the bigger crank will fit in the case and to the best of my recollection it has b pistons in it. I believe all the cylinders above 94mm are thinner. If more power is wanted from a 2.0 ,I would stroke it 76-78mm and try to keep the side piston load to a minimal by keeping the rod ratio length close to a 2.0. Otherwise your most prudent options are a solid rebuild with the addition of a cam and induction. Tom tuna had a great web site that had a lot of type IV info on it but most of the links are dead.


Here is a great link for a stroker kit in a 914.

http://www.ephotomotion.com/914engine/page18.html
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask.

[GTV]

[theKbStockpiler]

I only I have a torn down 1.7 so I'll just go with what I can remember.

- B pistons put the rings closer together which allows the piston to rock more in the bore.
-A longer stroke crank with the same rod; if the skirts misses the crank at bdc angles the connecting rod more.

B pistons really should not have to be used in a ACVW because the cylinders can be shimmed out away from the case. Most builders state that b pistons are okay but the more you stroke it the more the same length rod is angled. It might be that the offset of the piston wrist pin is not modified and hence causes problems.

I don't think that everything a manufacturer does can not be deviated from at all but placing the rings closer together and increasing the rod angle is most likely the cause of stroker engines suffering from abnormal wear. For a daily driver I would be conservative about it. If I was racing type IV's and had a pile of used heads and cases ,I would be building 3.0 with them.

[modok]

Going from a 1.85 rod ratio to 1.75 is nothing to worry about.
5.325 rods are often used.

Consider that in a type-1 we use 82 stroke with 137mm rod, in thin flexy cylinders. 1.67 ratio IMO that is pushing it. 1.74 ratio is still very conservative.

[theKbStockpiler]

I found 2 really good webpages on rod length.

This one is based on a 5.0 stroker and is about engine geometry for engine life http://www.strokerengine.com/RodStroke.html

and this one is based on performance.

http://www.stahlheaders.com/lit_rod%20length.htm
_________________
My beetle is not competing with your beetle. I have the yellow beetle in my town. There is a red one, a green one ......
Use all safety devices including a mask.

[modok]

From above website:

[udidwht]

[Air Cooleds Only]

You guys love talking about rods...

So far Sean & I are still set on trying out the 96 Biral's .
Experimenting is always a surprise.
Stroking it sounds like a good time
However sticking with the stock 2.0L 71mm crank and rods will help keep the cost down.
This will allow some extra change for Cam, & Valve Train Components, and all the other parts you don't account for right away.

From what I have read the T4 doesn't advantage all that much from a C/W Crank, unless it's a high revving machine . The case's are much stronger than the ole T1 platform.

I would like to get the full crank assy dynamically balanced.

At the present we need to decide which case to run with. Either one we can have fixed. Im leaning towards the 1.8 case, & having the one lifter bore repaired.
Tomorrow we will finish cleaning the case , measure & Inspect.

Thanks for all your input guys!

Chris
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Air Cooleds Only

[GTV]