Project Berg 1679 rebuild and update with squish!

[hotrodsurplus]

Good engine builders and tuners can time it by ear anyway, and so are not overly worried if their timing light is lost under a bench somewhere.

Oh now you're just being silly.

I want to clarify one thing: I'm not trying to impose my will. I'm not the expert. The argument I make is advocacy.

I'm so incredibly lucky to work with some incredibly knowledgeable experts in the automotive field, some of which are engineers trained in their area of expertise. I get to see a lot of the folksy myths shattered and trust me there are a TON of them. And yes, theories vary among builders and tuners but the information is pretty consistent among builders like Kaase, Robatnick, Dove, Beck, and others. The engines they build aren't test mules and they're quite frequently for customers who pay huge bucks for street engines. They don't take risks on $40,000 engines.

I don't want anyone to take what I say or any single other person says as gospel either. Do the research. You'll be surprised to learn what's out there.

And Martin, don't take this as me disparaging what you're doing. I really do want to see this work. And I think your engine builder is on point with things like deck height, CR, and such. I really appreciate that you're updating us. But I also want you to take the opportunity to expand your knowledge. It's a bittersweet feeling to know more than the experts you hire to work for you and I guarantee you that if you keep your mind open you'll learn more than most experts. 

[Martin S.]

According to Steve, grandpa was right! Take it easy on your new engine if you want it to last a long time.
When tuning on the dyno some tuners will go straight for the high end to start their tuning. Steve does the opposite and starts tuning by getting the motor to idle. Then works his way up the rpm range tuning the low, the mid, and then extrapolates the tune for the upper ranges using math. This way the engine doesn't get damaged on the dyno.
I picked up the car last night and it sounds unlike any stock mufflered bug I've ever heard. I have a crappy EMPI stock 30PICT1 carb on the engine which is total garbage. On the previous build it couldn't accelerate feeling like the accelerator pump wasn't working. The same carb runs fine on this new engine just because it will burn any mixture thrown at it. I do plan to switch back to a German carb, and it should get a 34PICT3 if anything. Haha, funny about the timing light. He tunes by ear for the most part, and using the laptop for fuel injected engines where a timing light is an anachronism. My wife left for work in the car this am, so I got a short vid of her starting the engine. Amazing how it will fire in a quarter turn and instantly idle (choke on) cold or hot, doesn't matter. Awesome!
The engine sounds more urgent, less lazy, with smooth power, no hiccups or glitches. Here's the youtube. http://youtu.be/sSXDBX6cXRQ

[modnrod]

Awesome!

Bloody lovely! 

[Zach Gomulka]

Peashooters?

[Martin S.]

As in 'old lady' stock. Amazing my marriage is lasting longer than that last engine build in 99.

[hotrodsurplus]

I picked up the car last night and it sounds unlike any stock mufflered bug I've ever heard. I have a crappy EMPI stock 30PICT1 carb on the engine which is total garbage. On the previous build it couldn't accelerate feeling like the accelerator pump wasn't working. The same carb runs fine on this new engine just because it will burn any mixture thrown at it.

Amazing what a little bit of compression will do ain't it? Increasing the efficiency decreases the BSFC which makes the engine more tolerant of iffy mixtures (to a point anyway). Back when I ran semi-hemi heads on my 1600 every carburetor felt 'broken' and I had to run like a 135 main in a 34. Flat spots abounded.

I do plan to switch back to a German carb, and it should get a 34PICT3 if anything.

Torben Alstrup runs them quite frequently on big engines that need to pass TUV and other certification standards. He might have some tips.

Haha, funny about the timing light. He tunes by ear for the most part, and using the laptop for fuel injected engines where a timing light is an anachronism.

You can't achieve consistency if you can't establish a baseline and recreate those parameters. How else can one determine an advance curve or total timing without a distributor machine? Certainly not by ear. Timing lights aren't anachronistic for injection tuning either. A timing light offers about the most convenient way to measure offset angle, the baseline for aftermarket injection tuning. A timing light is another measurement tool and to say you don't need one is to claim you don't need feeler gauges. You could build a house without a tape measure but it would take leagues more trial and error.

I'm stoked to hear it work out well. Are you getting any sort of rattle at WOT?

[Martin S.]

This engine makes the car a joy to drive. It keeps up with modern cars in traffic without a problem, no drama, just grabs and goes in any gear. I did get slight pinging when going up a big long hill in 3rd and gave it some gas but mostly I'm babying it until it carbons up some and breaks in the rings so no WOT on this motor yet plus you barely need to touch the gas with the torque. Steve said these squish motors need very little advance, and I should retard the timing 5 degrees from where it is now. I've got a vacuum dist with the small can right now. I'm going to check the total advance of this dist with the timing light soon. Then try a 009 because they don't have much for total advance. He said it won't help to have idle with a retarded timing and should have advance even at idle.  As for economy the first tank of gas got about 24.5 US MPG (29.5 UK) which is about 5 higher than before and I hope to get it better with some tuning and the 34PICT3 carb I'm going to try.

[hotrodsurplus]

Then try a 009 because they don't have much for total advance.

You'll find that an 009 has a ton of advance--in stock form way too much for an engine with lots of compression. The German ones usually have 22 to 25 degrees advance. I'm betting that the engine won't tolerate more than about 26 to 28 degrees total (mine at 8.1:1 and a .055" deck runs decent with 28 total, best with 30 total, and won't tolerate even 32). Assuming a 28-degree total timing and a 25-degree advance curve that means the base timing will come in around three degrees. You'll leave a ton of performance and drive quality on the table with three degrees of base timing. Insufficient base timing will make the engine feel real piggy despite the extra CR even with a stock cam.

I'm also going to say that the 009 is going to really disappoint you if you're going for any sort of fuel economy or part-throttle drive quality. The vacuum-advance mechanism will deliver lots more performance. I don't know what you have for a distributor now but I'm assuming that it's a small-body single-port distributor with a vacuum-only mechanism. For this application you might prefer a distributor with a mechanical and vacuum advance (like an early autostick or a dual-port distributor). If you run the dual-port distributor just don't run a line to the retard port (leave it open to atmosphere).

He said it won't help to have idle with a retarded timing and should have advance even at idle.

It shouldn't advance at idle but it should have sufficient timing at idle. Advance is a function of the mechanism altering the position of the points lobe in relation to the shaft and you want the advance to come in a bit later than idle if you want to avoid ping.

As for economy the first tank of gas got about 24.5 US MPG (29.5 UK) which is about 5 higher than before and I hope to get it better with some tuning and the 34PICT3 carb I'm going to try.

You should be getting way better than 25mpg even with this mild tune. Stock fuel economy is in the 30 range. My heavy lifted Thing with the big tires, surrey top, and less CR than yours gets 25mpg and its jetting is far from ideal. Good luck with that 34pict and an 009. You'll have lots of fun with that combo.

[Zach Gomulka]

Yeah, mileage should be better... My old 1679 was getting 27-28 right off the bat, 40PII's, stock cam w/1.4's, ported stock heads, 8.6:1. And I never babied it.

[Martin S.]

Hah, yeah, everybody gets better mileage than me.
The dist I'm using is a late model one with vacuum and cent advance and has the small vacuum can. The point of trying out a 009 is that it won't have too much total advance while still having enough advance at idle. With my current dist, to get the low total advance I want, the idle advance would be zero or less which is not ideal.
I'll try the different combos and run a tank thru it to check economy. Remember this motor runs a stock exhaust and cam.

[hotrodsurplus]

The dist I'm using is a late model one with vacuum and cent advance and has the small vacuum can.

That sounds like an autostick distributor. It's a good piece--about the best for your application. You're going to have to bend the stops to limit your total mechanical advance but that's not difficult. If you want to spend money then get a fully adjustable unit like a Mallory with a vacuum advance mechanism. Then you can fiddle with the amount of advance and the rate. The stock distributors don't offer that much versatility.

The point of trying out a 009 is that it won't have too much total advance while still having enough advance at idle. With my current dist, to get the low total advance I want, the idle advance would be zero or less which is not ideal.

You're going to be really disappointed with the 009. They have about the same mechanical advance as the stock distributor--maybe one or two degrees less than your existing distributor. That's not enough to warrant a change. In fact from a functional standpoint you'd be giving up more than you're gaining simply by eliminating the vacuum advance mechanism.

Remember this motor runs a stock exhaust and cam.

Which means you should get even better fuel economy. Longer-duration cams induce some reversion due to the late intake-valve closing event and increase overlap. Both of those hurt fuel economy. And the stock exhaust is tuned to give the maximum velocity within the speed range and engine size (well, within reason) that you run. A few years back I built a 1600 for a friend's convertible. We flycut the step from the chambers and got the deck to like .050". But otherwise it was a stone-stock dual-port engine with the stock muffler and everything (I shortened the curve a bit). It's his wife's car and she got 32 to 34mpg by just driving normal.

[Martin S.]

I haven't got great mileage with any bug (especially dual ports) except a 36hp that came in a 65 I bought once. I'm jealous of everyone who gets great mileage with these cars! Although I'm real happy with the 25 US mpg I'm getting with the turbo

[hotrodsurplus]

I haven't got great mileage with any bug (especially dual ports) except a 36hp that came in a 65 I bought once. I'm jealous of everyone who gets great mileage with these cars! Although I'm real happy with the 25 US mpg I'm getting with the turbo

Seat your rings properly and your chances will improve greatly. Of course then you'll suffer the premature failures that the rest of us do. I can't seem to get more than 20 years out of an engine.

My old coworker Ron Silva got better than 30mpg from his 2276 in his notch going from Costa Mesa to Bakersfield. We went 70mph once we got north of LA and that mileage included the Grapevine. Then he clicked off a 14-flat pass on pumped-up tires. 

[Ron Greiner]

What is the notch or groove cut into the top of the head for ?
I have not seen this before

[Martin S.]

It's a flame port, or singh groove. http://somender-singh.com/content/view/7/31/

[Martin S.]

We were talking about the next mileage motor build. Steve pointed out that the best economy engines (Honda, e.g.) were small bore long stroke. Thinking of building a stock length rod, stroker 85.5 motor. I wonder how it would work out piston pin-height-wise. And cylinder length. There aren't the piston choices in the kits sold in that size and I want to build it 'cheaply'.

[modnrod]

From Aircooled.net.........

This may be confusing to you, so here is a recap to clarify it.

If you use 88mm “A” Pistons use 5.325″ H-beam Rods and a 74mm Crankshaft, VW Rod Journals. Alternative P&Cs are 90.5mm A Piston and Cylinders, 92mm A Piston and Cylinders, and 94mm A Piston and Cylinders with the 74mm Crankshaft, VW Rod Journals, using the 5.325″ H-beam Rods.  Bigger bore engines are NOT going to be as MPG Friendly as the 85.5mm or 88mm bore engines will. But adding a big bore because the engine is apart, and “Why not?” are both valid reasons to do it!

If you use 85.5mm Stroker pistons, use the 76mm crankshaft, VW Rod Journals and 5.5″ rods. 90.5mm B Pistons and Cylinders, 92mm B Piston and Cylinders, and 94mm B Piston and Cylinders are also optional. Know that using the 76mm crankshaft, VW Rod Journals will require some light case machining, nothing major. If you are really uneasy about this, just go the 74mm Crankshaft, VW Rod Journals and either stock 85.5mm Mahle P&Cs, or the 88mm Slip Ins. We even have a nice Mexican 85.5mm P&C set if your purse strings are tight!

http://www.aircooled.net/vw-type-1-mileage-engine-mpg/


Stock pistons, 74mm crank, Porsche rod length.
Stroker ("B") pistons, 76mm crank, 5.5" rods.

The stroker pistons could also come out of a To#¤ta 3S-GTE or a 1JZ-GTE, both are 35mm pin height (same as "B" pistons), but are 86mm so you can hone out the stock 85.5mm barrels to suit, and the also use 22mm piston pin same as Type 1. I happen to have a 1JZ-GTE or 3 out the back, and the stock pistons will take 100HP per bore easily, my last 1JZ-GTE pumped out 250rwkW all day, and had 300K km on it. With a 76mm crank out of a wasserboxer (also use the flywheel, no dowels to break off) and 5.5" rods from John at Aircooled.net, you'd be good to rev to the moon for bugger all money. Do you have a wrecking yard nearby with a rusty old '90s Celica by chance?

You said it was to be a cheap racer, just thought I'd mention it in passing..........  

[Martin S.]

Great article, thanks! The other idea Steve had is to use EFI. He has a way to adapt a GM factory system and make it adjustable like a standalone yet cost a lot less.

[modnrod]

There used to be a system years ago called Kalmaker that did that, made the Delco ECU programmable. Locally we used to use the ECU off our Camira (GMs 4cyl fwd '90s platform), full OEM finesse with adjustability, excellent results.

EFI gives driveability and ease of tune certainly.

[Martin S.]

Talking more about the next thing to try on this engine with tuning. Since there was some ping going up a big hill, he said that the vacuum advance could be cutting in and causing too much advance. The late model dist is giving over 26 degrees total timing. I retarded the timing 2 degrees. This type of engine doesn't need the amount of advance of a lower CR engine. He's thinking that mechanical advance only would be good enough. Total advance to just before it pings is what we want, he said, which will make maximum power too. We are going to install colder plugs (there are stock Bosch ones in it) because it runs on after shutting off the ignition. That will be helped by putting a 34PICT3 carb on with the solenoid cuts off the fuel/air mixture.

[Zach Gomulka]

How about dual 36's and an exhaust? Too easy?

[Martin S.]

I'd like to keep it quiet for her so the new stock muffler and heater boxes will stay, but I like the idea of dual 36s. I've found that with our shit weather the duals tend to ice up less being closer to the heads. Duals are probably the best option, I'll try to find a set.

[hotrodsurplus]

Since there was some ping going up a big hill, he said that the vacuum advance could be cutting in and causing too much advance.

Opening the throttle enough to climb a hill increases the manifold pressure close to if not atmospheric level. Without low manifold pressure the vacuum-advance mechanism won't work. If you suspect that the vacuum mechanism is causing problems you can limit its operating range.

This type of engine doesn't need the amount of advance of a lower CR engine. He's thinking that mechanical advance only would be good enough.

The engine doesn't need as much mechanical advance as a low-compression engine does. But that doesn't mean that it won't benefit from the additional advance that a vacuum mechanism offers. Remember, vacuum advance is load conditional: it exists only during low-load applications like when you're barely tipped in to the throttle to maintain cruise speed. All engines benefit from earlier spark events in low-load applications because the cylinder pressure drops through the floor when the throttle butterflies are near closed. The combustion efficiency suffers in those situations and that results in incomplete combustion. The advanced spark incident lights the flame early enough to achieve adequate combustion.

Yeah, a mechanical-only distributor would work but that defeats the purpose of building an ultra-efficient engine.

We are going to install colder plugs (there are stock Bosch ones in it) because it runs on after shutting off the ignition.

The engine may well need colder plugs; however, the glow-plugging condition that you described isn't by itself justification to change temperature. In fact it's akin to loosening your belt as a consequence of gaining weight. It may make things feel better but it doesn't address the root problem.

Heat range plays the most vital part of WOT combustion and not the engine's general operating range. You choose a plug temperature based on the heat pattern on the ground strap. This explains it well. If these readings indicate that you need a colder plug then it's probably wise to do it. But to change plugs just because you raised the CR or are trying to address an underlying issue is a fool's errand.

http://members.uia.net/pkelley2/sparkplugreading.html 

That will be helped by putting a 34PICT3 carb on with the solenoid cuts off the fuel/air mixture.

An engine shouldn't glow-plug without a cut-off valve. Otherwise engines with Webers, Dellortos, Zeniths, Solex PII, Holleys, Carters, and Demons would suffer run-on problems.

You're running an application where you need a distributor that lends itself to tuning. As you've learned, conventional total timing figures will cause the engine to detonate. But retarding the entire spark curve leads to insufficient timing at idle and low-speed applications. Insufficient timing in those applications WILL INCREASE CHAMBER TEMPERATURES. The results you're getting suggest that the chambers are exceedingly hot (glow-plugging, preignition, detonation under load).

Your engine will benefit from a distributor that offers sufficient timing at slow AND fast engine speeds as well as an advance curve that matches the engine's needs. You're not going to get that with a production distributor like a Bosch. Your engine would benefit greatly from a distributor where you can manipulate those settings. Mallory for one makes such a distributor that also has the vacuum-advance mechanism. Sure, you COULD tune a Bosch distributor to do what you want but because those don't have any inherent adjustment properties you have to invent ways to do it and that's a real bitch without a distributor machine. The time and effort it would take to do that would far outpace the cost of a distributor that was designed for adjustment.

Look, I know you don't like me because I wrote some things that offended you or went against the teachings of your guru. But you would be foolish to dismiss everything that I say just because you think I'm an ass. The information that I've presented is very conventional and well proven by decades of tuning. This is how the rest of the world does it. You need to research the causes and intelligent solutions because band-aid solutions will only compound the problems.

[Zach Gomulka]

I'd like to keep it quiet for her so the new stock muffler and heater boxes will stay, but I like the idea of dual 36s. I've found that with our shit weather the duals tend to ice up less being closer to the heads. Duals are probably the best option, I'll try to find a set.

My point is that one venturi per cylinder is more efficient, and the stock exhaust isn't just holding back power but heat as well, could be part of your problem.

[Martin S.]

Just to clarify, there really isn't much of a problem. Even the fuel economy is excellent for me. In Toronto the traffic is spazmodic so it is hard to compare to someone else's driving conditions. I'm loving the car again now that it's being so good. Tweaking it is fun and I'm keeping track of mileage. Of course the easiest solution is for her to get a Honda, but that wouldn't be as fun. 

[hotrodsurplus]

My point is that one venturi per cylinder is more efficient

Totally agreed. It helps atomization big time and eliminates fuel-distribution problems inherent with the firing order and cylinder layout (cylinders 2 and 4 disrupt the AFR for cylinders 1 and 3). That said I think you can make the system work fine with a single carburetor and a short-duration cam. I mean every other single-carburetor engine seems to pull it off.

and the stock exhaust isn't just holding back power but heat as well, could be part of your problem.

I don't think the stock exhaust hurts in this application. This engine is less than 200cc larger than stock and it doesn't spin any faster than stock. Look at it in terms of gross volume. A 1776 is only 12 percent larger than a 1585. So a 1776 at 3,200rpm flows about the same as a 1585 at 3,600rpm.

Sure, that exhaust on a 2-liter engine at 5K rpm might generate enough resistance to increase EGTs and CHTs. But that exhaust on a 1776 bumbling along at 3,200 shouldn't cause problems.

[Martin S.]

  This 1776 does more than bumble along. It's got over 500 miles on it now and I haven't stepped on the gas much yet, as there is no need to in order to keep up with traffic and I'm babying it until it's broken in fully.

[Martin S.]

Speaking of heat, Steve said that the exhaust temps go up using EFI compared to carbs. They found that by richening up the mixture enough to lower the exhaust temps back to what they were with carbs, the engine was now running too rich. EFI is that much more efficient than carbs.