914 engine into a 72 Westy

[vacca rabite]

Hey all,

About a decade or so ago (holy moly!) I built a 2056 for my 914. Its been a great engine.
Raby 9530 cam.
Ceramic lifters
cromo cut to length pushrods, with the full spacer kit for the valve rockers.
Mahle stock cylinders, bored out
KB flattop pistons
New bearings, etc.
Static CR around 8.6:1
everything was dynamic balanced
1.7 heads with 2.0 valves.

A few years after I built it, I decided to do Microsquirt, and so now the engine is crankfired and has modern EFI.
It screams in my 914, and runs nice and cool, and dynoed at 127HP at the wheels.

This engine is going to go into the bus I am restoring, and 2.3 is going into my 914.

So now I'm going research.
I know I probably should not just drop this motor into the bus and expect it to survive.
My thoughts right now are to split the case and change cams to something that is built more or torque and cool running in a bus.

So questions:
For a 2056 in a bus - whats the combo these days that I need to be looking at.
What cam do I want to be using for the bus? I highly doubt its the Raby 9530 or any of the Web494 derivatives that I have used in 914s.
Can I reuse the cast cylinders and KB pistons and just do a new hone and ring? Or do I need to change to something that is going to shed heat faster?
What kind of static CR do I need to look for for a bus? (I'll be letting the CR drive the deck height).
Do I need to be thinking about coatings for the case and heads for a bus engine?
The bottom end of my engine is solid. Though if I am splitting the case for the cam, am I going to anger the gods of engines if I don't do the main bearings at the same time?

Thanks!
I look forward to seeing where this thread goes.
Zach

[bushoarder]

Your engine sounds ace!

I’d say if your efi is fully programmable then just change the map. You can build in fail safes for temp and advance etc in the software. Let the electronics do their thing and see how it runs first.


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[Thenoj]

What are the specs of the 9530 cam? Maybe you could lower the CR a bit and re tune it.
I don’t see why you couldn’t hone and re-ring your existing cylinders and pistons if they are in spec.

[Clatter]

FWIW, I'd be inclined to open the motor up for a check-out and to make the specs more match the bus application.
If everything measures out fine, no harm in re-using anything, even rod bearings.
Lifters, you'll want to replace when you buy a new cam, or at least have them re-surfaced.

I'd get a camper special cam from LN (can't remember the number off-hand) and set the CR to match.
Usually around 8:1..

Using the flat-tops, it will be interesting to get your CR down to around 8:1 without gaining too much deck in the process.
Depending upon how your heads were done, and the chamber volume, you may/may not have too much deck.
You might be OK, or maybe get away with some un-shrouding, or..?
I go over this in the build thread in my sig.

While 96s for a bus motor aren't technically ideal, if you tune carefully and run it right they will be fine.

A big consideration with a bus is getting a nice exhaust that will get the heat flowing out and away.

Sounds like some good fun. Love these motors!

[vacca rabite]

The lifters in the engine right now are ceramic. No refinishing needed.

I actually HATE putting those lifters in a bus, since they really benefit the 914. But you can't find the ceramic lifters anymore, and I'm not willing to take my 914 off the road to pull the lifters out, so the new 914 motor won't use them.

What are some recommendations for the exhaust? I will be getting rid of the heat exchangers and going diesel heater for heat, plumbing that into the stock heater tubing so I get things like the windshield defroster. I'm also thinking ceramic coating the exhaust pipes will help keep all the heat from the pipes moving out the exhaust pipe and not radiating back up baking the bottom of the engine.
Zach

[Clatter]

Couple of questions come up..
FIrst = what kind of bus?

A light early split Kombi that's upright converted and just used empty for shows?
Or a super-heavy late camper loaded to the gills pulling mountain passes for hours at a time?

This would determine how much change I'd be inclined to make on the motor during the switch.
That, and how much fun it is for you to pull/build/stuff these motors.
I do it all the time for fun but I'm sick like that..

Also, the best thing about those ceramic lifters is you can just switch them over to a different cam without resurfacing, right?
Are they type 1 lifters with a head?
If not, you can just pull the pushrod tubes and they slide right out.
No need to even remove the motor from the car, much less the heads.
Best practice is to buy lifters with the cam, so not sure where an issue lies.

If you're using another heater, then that's excellent news for building a Bus motor.
72-74 heater boxes are usually favored, but are getting hard to find.
A T-bird or it's China copies now were always to go-to.
You could use a set of 411/412 pre-heaters, or strip those, or a set of heaters down to use the pipes inside.
That's the cheap/easy way, but works really well and long-term.
There are those EMW equal-length head pipes that are heater box substitutes and, well, equal length.
Not sure they are still available new?
Also some really really nice exhausts from Tangerine racing or in Europe if you got the skrilla.
Chris used to make Bus headers, don't see them on the site, but bet he would do another.
http://www.tangerineracing.com/tangerineheaders.htm
https://www.ahnendorp.com/VW-Type-4---P ... xhaust-80/

Most important will be a true tuned-length header with a collector to pull the hot exhaust out of the engine.
The one biggest enhancement to keeping my bus cool was a better exhaust.
Avoid the 75-78 F-pipes or any kind of exhaust that is just a "can" built just for looks and sound but not function.
In other words, don't take the bait on anything shiny from Taiwan.

Since you can tune well, You might be able to get away with either some more deck, or more CR and cam duration.

Just depends upon so many things... Doesn't sound like you can go wrong no matter which way you go.