Best way to build a 150+hp engine?

[AutocrossOrange]

Hello everyone!

I've been poking around this forum for a few months because I am looking to build a Type 4 engine to swap into my 1974 Super Beetle. The car will be used as a daily driver as well as an autocross car. I have purchased a Type 4 case originally from a Bus as the foundation of the project. I have some experience with maintenance, but not a clue about engine building. I have been reading forum posts and the Tom Wilson aircooled engine rebuild book to try to learn a little about the process. There seem to be some very knowledgeable people here, so I thought I'd pick your collective brain for advice.

These are the attributes I am looking to attain with this engine:

- 150hp (more is fine if expense and work are not much greater)

- Naturally aspirated

- Relatively flat power curve

- High redline (over 7000 if possible)

- Hydraulic lifters (for ease of maintenance and longer engine life)

- Run on pump gas (93 octane max)

My main question is what is required to build an engine with these characteristics? I have no idea what the best options are regarding displacement, stroke, valve size, head type, cam choice, etc. I know machining of the case and heads is required to install larger pistons, but I would like to avoid major modifications beyond that. If any of my expectations are unreasonable, tell me so. Thank you in advance for the help.

[Piledriver]

Welcome to the STF!

Totally possible, but the hydraulic lifters and 7000 RPM goals are totally conflicting.

Well proven combo:
Good heads (42 or 44x36 with good port work) preferably based on AMC castings.
Webers or EFI//ITBs with good cable linkage
2270, Rimco "Super" rods (reworked stock 2L with Carrillo bolts) or Hbeams.
Great exhaust--
----A1 makes a great one that isn't too ridiculously priced (not the sidewinder, has issues)
Webcam 163/86B@102 or 104 LC (or in that ballpark)
Tool steel T1 lifters if you can swing it. (with bronze bushings)
Real 911 swivel feet valve adjuster screws in modded 1700cc rocker arms.

In my experience, most valve adjustments are driven by wear at the adjustment screw, or the exhaust valve stems stretching over time. (They all do it to some extent)
The 911 screws are a big aid and also seem to reduce funky guide wear.

The original oil pump is FINE if not worn out, the aftermarket pumps don't fit properly (loose for easy assembly I suspect) , and will need to be oringed, which is only a partial fix.

I was stoked awhile back when I scored a factory HD T1 pump (factory reman engine w/low miles) these can be easily modded for T4 use and they fit properly...


Should make 150HP++ with a great tq curve without much worry.
(peak HP will mostly depend on the heads used, 200HP is doable, depends on your wallet)
.....
Hydro cams have been beaten up by better before, but here's a condensed version...

The only cams that are hydraulic lifter compatible by design are stock or close.

Hydraulic lifters can be used on any mechanical cam but you will lose some duration, and they have a nasty habit of "pumping up" and keeping the valves off the seats at high revs... like over 5K.

The "racing" hydro lifters you may have seen advertised for v8s are typically "cheater" hydros--- the "anti-pump-up" feature is actually that they are internally shimmed to only have about .005" stroke, so they can only pump up that far.
Functionally they are solid lifters, but they pass tech inspection due to having some "squish" when rocker is pushed.

All the replacement hydraulic (and a lot of the generic "replacement" t4 mechanicals) lifters I have seen are ground flat on the end, which is absolutely, 100% wrong. You can take them apart and have them ground properly and coated for a reasonable price, but its something "extra" you need to do.

You cannot use mech lifters on true hydro cams as they have violent initial ramps to quickly close the ball check valve in the lifter, a solid lifter valvetrain on a real hydro cam will be beaten to death in minutes.
(I have been told that most "hydro" cams sold for the T4 are not true hydraulic lifter cams, just mild solid cams that work ~OK with hydraulic lifters)

Hydro lifters also like to suck air when the engine is off and the oil leaks out of the horizontal lifter, leaking to random nerve wracking (and wallet puckering) noises coming from your engine on startup. This is usually only an annoyance.

You also lose the ability to easily detect a valve stretching or seat sinking etc during regular valve adjustments,
---which you STILL need to do regularly with hydros,
...esp if you race it---its really not that hard to do, esp if you spring the $20 for the silicone glue-in valve cover gaskets.(permanent)

This final one is the killer, esp if using stock head castings, and why CrMo pushrods and zero lash is the typical setup, as the lash increases with a hot engine, rather than getting smaller... providing some safety against burnt valves/seats.

[AutocrossOrange]

Thank you! Ok. It sounds like hydraulic lifters aren't going to be feasible for a non-stock engine. I can live with that; I do them every 3k miles on the stock 1600 anyway.

I apologize. I'm about to barrage you with questions because to understand I need things spelled out for me.

For a 2270cc engine, what size pistons and cylinders are used? Does it use stroker crank? What rod length do I need?

Where do I get large valve heads? The only heads I've found while browsing are stock replacements, or the Type 4 store CS and RS+ heads which both have a 42mm max intake valve size.

Regarding the cams, it seems the only difference between the two you mentioned is that the 163/86B is a split duration with more exhaust duration than the 104 LC. Is the extra exhaust duration beneficial?

What is the purpose of running Type 1 lifters in a Type 4?

What sort of pushrods / valve springs should I use?

I had Weber IDFs in mind for the engine. What size would be best (44,48)?

[Piledriver]

A 2270 is 96x78mm.

A tremendous amount of info is in the stickies.
If you are serious, there is a lot to read.

Hopefully Richard will have some input.

I suggest you build a healthy 2056 (96x71, stock bottom end) first, with decent heads and that cam etc it will make good power and it goes together ~like stock. It will show you the limits of a stock T1 transmission easily if you don't take some care. 150HP is not out of the question even with that but you'll be working it a lot harder, and have to sacrifice tq to do it vs. the 2270.

The extra exhaust duration is generally highly beneficial on a T4 as the exhaust ports are difficult to port to keep up with the intakes. It is important to keep the ex valve size down due to the seat drooping issues, very little metal and no cooling between the seat and the port, there is ~no room for a short side radius, and you supposedly shouldn't even attempt to make one when porting, don't even smooth the corner.

It does appear Jake no longer sells his better heads except on his turnkey motors...?

Fortunately Adrian at Headflow Masters seems to still be in business, and there are other vendors that "do" T4 heads, although I can only personally vouch for HAM (Hoffman Machine) and Adrian (Headflow Masters) work, and Jake may keep HAM busy full time. He once used Adrian exclusively but Adrian can be a flake sometimes.

It would probably be a good idea to call Charles at the Type4store he may have a way to get the LE200s etc, don't know.
Bring your wallet.

Consider a set of Nickies and some 4000 series alloy JEs while there if you have a healthy budget.
They run with ~stock clearances and noise and will last a LOT longer than the typical buttery soft JEs or Wisecos, they both also make harder 4000 series alloy forged pistons, that's ~what you get if any car has forged pistons from the factory.

Wiseco specifically recommends against the 2000 series alloy pistons even for endurance racing, the ring lands wear out very quickly, the 4000 series last ~like stock, but a lot tougher. They will be custom as all the forged ACVW pistons off the shelf are for drag racing and are 2000 series alloys.

Brothers Machine seems to sell a lot of heads, can't personally vouch for the porting etc.
Someone else advertises as well, name escapes me but has been discussed extensively.

I don't think EMW does porting, but they can certainly recommend someone and do all the machine work.
Aircooled.net may be able to set you up as well, trusted vendor.

Whatever you do, make sure they get built on new AMC castings, MUCH better than factory.

The tool steel T1 lifters are are least likely to have cam issues (better than anything save for the $$$$ silicon nitride ceramics), and are MUCH lighter than a T4 lifter, and will not shatter as the ceramics can if you get into valve float if you say grab the wrong gear.

Mario and others sell the lifters, but you probably want the bronze adapter bushings, not sure who sells that setup anymore..

[raygreenwood]

Also....42mm intake valves are not too small for a 2056 (depending again on cam, exhaust and your intake system and how you are feeding it).

Don't immediately try to talk yourself into the largest "everything" you can get.

Just a question....where is your 150hp figure/need coming from? Have you ever driven a 2000 lbs car with 150hp and probably 165 ft/lbs of torque?

A quick for instance....my 2012 golf....170 hp and 177 ft/lbs or torque. 3500 lbs of fat and steel with me and my junk.
While some say its not quite sporty enough...alla those dumb-asses bought the automatic . It does a credible 8 seconds 0-60....and well driven its 50-75 mph time is scare most Honda and similar sized cars out of my way.

Thinking this way....that kind of performance for a daily driver is a decent benchmark for viewing.
Thats 0.04857hp per pound...or 20.588 pounds per horsepower.

Another viewpoint....my VW412...with four speed....and with its last engine at about 90 rear wheel HP and 102 on the dyno...with a 1.7...drove almost exactly the same way as my golf....very similar acceleration (just about 1 second slower 0-60...except my 412 had a 96mph top end (gearing) and my golf is limited to 93 mph by its governor.

The 412 weighed 2200 lbs dry and about 2500 with me and fuel. Using the 102hp dyno figure....that works out to 0.0408 hp per pound...about .008 less hp per pound than my Golf.....and 24.509 pounds per hp....so you can why its not that much slower 0-60 than my more modern golf.....and....with the factory supplied 82hp in my 2200 lbs (dry) 412....the factory 0-60 time was about 13.2 seconds.
Its amazing what 20hp and better throttle response can do. 9-10 seconds 0-60 instead of 13-14 seconds 0-60. Another 10hp in the same car and 8 seconds 0-60 is a reality. That is excellent daily driver material.

Most people are stunned at what a true 125hp with about 120 ft/lbs of torque will do in a bug. Ray

[AutocrossOrange]

The power figure is a fairly arbitrary target. I figured since a stock 2.0 from a 914 makes roughly 100hp, a 50% increase in power wouldn't be an unreasonable feat to accomplish. Also, I wanted to best the power-to-weight ratio of a Porsche 911 of similar vintage, which at 150hp the Beetle would easily do.

I guess a more concrete reason is I wanted to make the extra cost of building a Type 4 engine "worth it" over just building a performance Type 1 motor. Ignoring the reliability aspect, I'm having trouble justifying the trouble of the conversion to put in a mostly stock 2.0 Type 4 in, when it would cost considerably less to rebuild and modify my 1600 to produce ~100hp and get almost the same result.

[raygreenwood]

The power figure is a fairly arbitrary target. I figured since a stock 2.0 from a 914 makes roughly 100hp, a 50% increase in power wouldn't be an unreasonable feat to accomplish. Also, I wanted to best the power-to-weight ratio of a Porsche 911 of similar vintage, which at 150hp the Beetle would easily do.

I guess a more concrete reason is I wanted to make the extra cost of building a Type 4 engine "worth it" over just building a performance Type 1 motor. Ignoring the reliability aspect, I'm having trouble justifying the trouble of the conversion to put in a mostly stock 2.0 Type 4 in, when it would cost considerably less to rebuild and modify my 1600 to produce ~100hp and get almost the same result.

A lot of research to do that will help this decision. I would never use a stock 914 2.0.

The cost versus bang per buck locked up in the 2.0 only heads for 100hp...and less throttle response....and thats with D-jet. The 1.7L...nicely tuned.... beats the 2.0 914 with D-jet for throttle response. Almost all of this is due to differences in the injection manifolds....and its all stock...old stock.

There were some great design features in the 2.0 914 heads. All but the plug angle can be worked around with other heads...that have less self destructive qualities.

Also bear in mind....still thinking stock 2.0 here....all of that cost to make 100hp you note...and all of that cost was wrapped up including a really crappy exhaust, a super-duper crappy cam (compared to what you can get now for half the cost)...and a really weak ignition....and very poor factory tuning compared to what is actually possibe with D-jet.

My point?

So...if you still want to put in what you call a 2.0....make it about 8.5 or 9.0:1 compression, new heads, same chambers, same valves with slight porting...a far better cam than factory had as Pile suggested (and that includes excellent pushrods, lifters, swivel feet etc.), a real exhaust system, and even going to Hall effect with a 55KV coil is light years ahead in the stock distributor. You cant really use the the stock efi manifolds of either 1.7 or 2.0 (and the 1,7 were really very good)...in a bug with upright or DTM...but you can go twin carbs at worst...or twin TBs with even aftermarket simple CB injection...or megasquirt.....and that same 2.0 sized engine with easily be about 115-120hp or better with a huge bump in throttle response.

A 2056.....would really be what you are building. The 914 was at its minimum best really with the 2.0L. Thats not because a 2.0 wasn't enough for a 2100 lbs car....its because they way the 2.0L 914 was built...systems wise (cam, ignition, intakes, injection, exhaust)....was at its absolute maxed out limit to make that 100hp. The engine configuration and combustion chamber and valve size...were not maxed out. The original 2.0l could have easily been a 120hp engine....with better systems attached to it.

With the right cam, exhaust and tuning and TB work even with the original D-jet...it still can be.....but reliability suffers.

My point of my earlier post....was that its amazing what 20 hp can do in cars this light. The 82hp 1.7L in my 412 with an extra 18-20 hp....is amazingly quicker and more fun to drive. In a bug....115-125hp is a lot for a street daily driver bug.

I mean really.....I would be stunned...if your 1600 is really putting out more than about 50-60hp now.
You have the HP to weight ratio...even at 100-115hp (if you also install the gearing to exploit it)...that will easily contend with most 150-175hp (and some with even more) cars modern cars on the road.

I say this as well...because if you are building a type 4...and its your first.....a 2056 (stock 2.0 stroke) is one of the simplest and best bangs for the buck....and will have plenty of HP if well tuned for a daily driver. The price goes up markedly from there. Ray

[AutocrossOrange]

Just to be clear, it was never my intent to use 914 heads, cam, or fuel injection for my build. I was merely using the 914's power output as a frame of reference, since it was among the most powerful factory-produced configurations of the Type 4 engine.

A 2056 is starting to sound like a good way to go. Since this will be my first longblock build it would definitely be a good thing not to have to do anything crazy with the bottom end. The engine would still have a lot of power and would last a very long time as long as all parts are balanced well and I assemble it with care.

[Piledriver]

Same cam/heads/exhaust recommendation for a 2056...
Use good rods (the ones mentioned count) as you can spin it a little higher with the smaller motor.
You do not need a counterweighted crank on a T4, just a good balance job.

With ~9:1(or slightly higher) compression and a reasonably tight deck it will scoot, a 102 LC cam increases the dynamic CR somewhat, but 104 wont be much different. You should be able to run regular @9:1 with the 163/86B@104LC (std LC for that cam)

A bit more compression would make more power but will be hard to get with a 2056 with flattops.
You should NEVER flycut for compression on a T4, not enough meat in the deck as is.

A 119/163 @104 might be a custom option to make better use of lower compression.
An 86A or 494 is also a good call in that compression range, a bit less lift, technically HD single springs will work but I suggest duals for anything much hotter than an 86, as it can pull past 6K. The 86/a/b/c cams are based on an OEM chevy pattern that's pretty easy on the lifter bores/valvetrain, the 494/119/163 are more aggressive.

44/36 IDFs 45 dells or 44mm or smaller ITBs (40 OK, even 38mm ITBs are going to flow more air than 44/36 Webers).

I ran 44/36s on a stock 1700 914 motor (factory domed pistons, no head or cylinder base gaskets for little bit higher compression and ~.028" deck.~8.6:1 with the stock cam is a lot but it still ran on regular.
Ran it to 5600 redline in 1-3rd at every highway onramp for a ~decade with Webers and later CIS injection, which was hassle free once set up, but Megasquirt would probably be a lot easier and allows many excellent ignition options.

Even the essentially stock 1700 with Webers was grin inducing in a Bug, may have made 90 actual HP with a tailwind.
That's still ~50%+ over what the vehicle was designed for, and it had tire shake on launches until I made up a kafer brace.

I still run that uncut block and the original factory KS main bearings in my current 1800 incarnation with 2L porsche heads and a web 73 in my squareback, 80 miles a day. the EA block has seen well over 400K miles so far.

The only thing that drove a rebuild was the cam thrust bearing was worn/beaten off, causing weird bottom end noises.
Still ran just fine.

[raygreenwood]

Just to be clear, it was never my intent to use 914 heads, cam, or fuel injection for my build. I was merely using the 914's power output as a frame of reference, since it was among the most powerful factory-produced configurations of the Type 4 engine.

Yep...I figured that. I was just pointing out that They did a great job with what they had for that era.. in a tight package.

Working along stock lines....stroke wise....for your first build....you have quite a few more options now...to improve the basic 2.0 package enough to put out BETTER and more reliable horsepower than the stock 2.0.

I guess my main point is that there was quite a bit more power and throttle response available in even the stock engine configurations just through tuning abilities these days...the ability to use exhausts the factory could not (costs) or cams the factory could not (cost and emissions), injection/carbs the factory could not (cost and emissions), ignitions the factory did not have...and lots of little but significant trinkets of tuning....without wholesale changing of everything.

Planning wise....its easy to make 150 hp engine....just make it big. But in reality with any ACVW...and type 4 especially...the ACT of making it big....gets into considerable expertise and COST. As the engine increases in bore and stroke....everything has to change...and everything needs machine work...and everything is custom. Ray