1679 build for low end power.

[Oldschoolblake]

Car:
'71 beetle, stock transaxle.
It is lifted with a 235/75 tire size for the class 11 look.
Occasional driving, mostly used for trail riding.

Have the original AE code case and dual port heads.

Using:
stock flywheel, modified for 8 dowel.
Cb performance 4140 69mm crank.
berg equalizer, or achiever. Undecided.
stock rebushed rods.
88mm A A thick tops
Stock heads, stock valve size, single HD springs.
Cb 1.1 rockers
Pertronix SVDA dizzy
Single 40 IDF.

Going for low end power in lower rpm ranges.
What cam would you use?
I'm fine with a loping idle.
I've looked into:
norris 329s/330s
Scat c25
Web 218
And some other similar cams.

W-100 & web 218 seems like too much valve lift?

What size 4-1 header should I go with?

[Oldschoolblake]

The reason why I'm asking about cams is the considerable difference in lift between cams that offer similar power according to the description.

Here is an example description:
#329S - THE "BUS CAM", MILD STREET CAM, OFF ROAD CAM - This cam was originally designed for bus engines, way back in the day.  It helped moved heavy cars with low displacement engines.  The super torque proved great for mild performance engines on standard VW's as well, and is also well suited for heavy off-road cars with smaller motors. We've found that this is a great cam for small displacement engines: 1641cc, 1679cc, 1776cc, etc., with mostly stock components. It's not hard on valvetrain components and can It pulls hard and still idles very smoothly, even down at 800-900 RPM's.  You might compare it to an Engle 100 cam. Unlike the 100, it can be used with stock (1.1) ratio rockers, or it be used with 1.25 or even 1.4 ratio rockers.  Using larger rockers will allow you extend your powerband, add horsepower, and allow you to fine tune your engine dynamics without having to split the case and change your cam again if you decide to give it a little extra zing later.  With the right combo, these will run well up to about 6200 RPM's. Will work great with standard valve springs for stock rockers. Recommend HD single springs for 1.25 or 1.4 rockers.  Very easy on lifter bores.  This cam is a great choice for an engine built for longevity.

ADV DURATION -- DURATION AT .050" -- CAM LIFT -- VALVE LIFT 1.1 -- VALVE LIFT 1.25 -- VALVE LIFT 1.4
272 degrees -- 232 degrees -- .329 -- .362 -- .411 -- .4

so this is comparable/similar to a w-100?

Norris 329s:
Cam lift: 329
Valve lift: .362 using 1.1 rockers
Adv. Duration: 272°

Scat C25:
Cam lift: .332
Valve lift: .365
Adv. Duration: 272°


Engle W100:
Cam lift: .383
Valve lift: .420 using 1.1 rockers
adv. Duration: 276°

All have 108° lobe separation. (Lobe center)


Engle uses a lot more lift to make the same type of power as other cams.
Which is confusing to me.

the scat c25 is also said to be similar to the w100.

[Marc]

Bugpack 4061-10.
~.400" lift w/1.1 rockers can still use stock adjusters, provided you get the geometry right. IMO an engine this size doesn't really warrant the heavy pulley, so there's a place you could save a few bucks.

Are you planning on fitting a skidplate to protect the exhaust system, or would you run an open engine compartment so a buggy-style exhaust could be used? I doubt that you'd notice any difference between 1⅜" and 1½" systems of similar design; selection will probably come down to what'll fit and not get ripped off in the rough stuff. You're also going to need all the intake manifold preheat flow you can get, without it there'll be a gigantic flat-spot when accelerating at low RPM - so if you select a system that has no heat riser flanges you'll have to weld some in. Of course, most single IDF manifolds are a joke when it comes to manifold heat - it's worth springing for the "deluxe" type that addresses the issue.

Although never sold in the US market, there were 1300cc IRS Beetles in Europe and Canada which came with a 4.375:1 ring & pinion which'd be good for this application; keep an eye out for an "AM" trans.

http://vwparts.aircooled.net/Deluxe-Cen ... 04.315.htm
http://www.shoptalkforums.com/viewtopic ... 8&t=131321

[Oldschoolblake]

Thanks for the input Marc.

The heavy pulley, people have suggested using one in this type of engine.
The extra weight is for inertia rather than harmonics.
I'm not arguing, it's just what I've found in research, I actually don't know as I haven't used anything more than an AE code stock 1600 dp.

That cam looks good, although there are sooooo many similar cams.

for exhaust, it is a full body beetle.
honestly the 2 tip gt style exhaust (oem Mexico style) has the most to offer in location and ground clearance.
I have read a lot of poopoo feedback and reviews on them.
a dyno test showed it to loose hp & torque on a stock engine.

so I'm looking at something like this, the header is in related parts.
http://vwparts.aircooled.net/Hide-Out-M ... 556-13.htm

Looks more easier to rip off or beat up though.

[Marc]

That cam looks good, although there are sooooo many similar cams.
...Looks more easier to rip off or beat up though.

Yes, and any cam in the low 270° adv dur (with stock lobe centers) is going to yield roughly the same performance. For what you're doing, a Web 86 would make more sense than the 119 or 218 IMO, but the lift is a little low compared to the Bugpack 4061. I suggested it because IMO it'd be the best compromise, all things considered - it has fairly rapid action (needed to boost low-end) yet the ramps are gentle enough for single springs, lift sufficient for stock heads yet low enough that rockeram geometry shouldn't be a challenge. By the time you get to ~.420" lift rocker geometry becomes a little harder to set up (swivel feet recommended, but you must make sure not to exceed their travel range).
Dropping the L.C. to 106° will give a higher, lower torque peak at the expense of a slight loss in top-end power. Web-Cam would probably be the most accommodating for such a grind. They offer a grind that's a real torque monster (the 111) but it's very hard on the valvetrain and I'd shy away from it for a driver...it has .476" lift w/1.1 rockers and requires dual springs so it's out of the running anyway. Engle's VZ-14 would be gentler, but even it's a "clacker". As you've probably discovered, some lift specs are given at the cam and some at the valve (with various ratio rockers) - some charts you'll find on the 'net muddle those figures.

Besides the substantial mass of the hideaway muffler, it has to come off to get to the RH valvecover. I can't think of any system for a full-bodied car that I'd run off-road without a skidplate. The performance difference between the "worst" exhaust and the "best" is probably no more than 3 HP...sometimes the pragmatic answer is to give up a little power in the interest of durability.

As for the heavy pulley, consider that the diameter is much smaller than that of a flywheel and the inertia varies as a fourth-power function - in other words, it has much less effect than an equal change in flywheel weight....and the effect changes with the square of the speed. In short, at low RPM you'd get about the same effect from the difference between a heavy LUK clutch cover and a lightweight Daikin (and it won't be that much in either case).
http://www.calculatoredge.com/mech/flywheel.htm

[The Newf]

For what it's worth,I've always wondered about adding the extra mass to the pulley side of the engine because of the small main bearing supporting that end of the crank.

[Marc]

If that scares you, don't look at an aero conversion where the propeller's hanging off of there

[Oldschoolblake]

I think ultimately I am going to choose the GT muffler.
The dyno test was on an all stock engine as well, so maybe a slightly larger (better flowing) engine will match up to it.
In the end it will function more to what the design of the car needs.
Plus, a skid pate wide enough to protect the heater boxes can easily be extended more towards the apron to cover the whole muffler.
Plus it actually sounds good, to me anyway.
http://m.youtube.com/watch?v=s8CROr0zWbw

[Marc]

I had presumed that you were planning to forego heater boxes and run J-tubes. Stock heater boxes will still be fine (if a bit heavy) but make it pointless to run anything bigger than a 1⅜" system. You should be happy overall with the GT muffler for your needs, even though it's not much for performance...about on a par with a stock muffler with the tailpipes removed, but much more pleasant-sounding. It doesn't provide as much preheat flow as a stock muffler, but if you find that the flat spot is more than you can live with it would be possible to plumb one of the heatriser pipes into a low-pressure point similar to the stocker's arrangement. Meanwhile, just drill the holes as big as you can without hitting daylight.

[Oldschoolblake]

Here is a thread where I was asking about the muffler, some one shared a Volksworld article about empi & vintage speed systems.
Includes the dyno tests, is a good read.
http://www.thesamba.com/vw/forum/viewto ... ht=muffler

[Oldschoolblake]

I looked around,
The web cam grind 86 or 119 are both available with 105° lobe separation.
Not available in the 106° lobe separation that you mentioned.

Would the 105° do about the same as you mentioned?
Also will it change idle characteristics?

[Marc]

105° should be fine. I used to use their 121 grind on a limited-intake racecar engine and it boosted low end significantly compared to 108°. I figured WTH and had them do me one on 102° - wicked-sounding idle but power was lower

When you close up the lobe center (more properly it's called the lobe separation angle, but LC has become the vernacular term) you get more overlap (more degrees of crankshaft rotation wherein both the intake and exhaust valves are slightly open). This causes more of the intake charge to be swept out unburnt so the idle emissions numbers go to hell, but as RPM rises the exhaust pulses aid cylinder filling which improves torque.

When you're working with a single camshaft you don't have control over the individual valve events (intake open/close, exhaust open/close) but of the four the intake closure has the greatest effect upon the powerband - closing the intake sooner lets compression begin sooner which raises the cylinder pressure more by the time combustion begins. But as RPM increases, it's better to leave the intake open longer in order to take advantage of the inertia of the incoming charge and fill the cylinder further. Late closure delays the beginning of compression, but since there's more in there to start with the cylinder pressure will still be higher at high RPM. By fiddling with the LC you can change the intake events and leave the exhaust events as they were...but in either case (changing overall cam timing OR narrowing the LC) if you need to make a change greater than 2 or 3° you have the wrong grind to begin with.

My gut feeling is that the added lift of the Bugpack 4061 on 108° would make it at least equal to the Web 86 on 105°, and the Web 119 on 105° (or for that matter, on 108° but advanced a couple degrees) would surpass them both for your needs...but it has .422" lift with 1.1 rockers, so setting the geometry's going to be more a little more challenging. If that doesn't scare you off, get the 119 - and ask Web for a second opinion as to which lobe center would be best for you.

Never forget that it's almost always preferable to choose a slightly too-small cam than one that's too big. In the first case you may lose a tiny bit of performance, but it'll be easy to live with. Go too big and you'll regret it every time you're in traffic.

[Piledriver]

You can also get a SSC trans with a 4.12 R&P from a late T3 as a slight help for the big tires.
(code AH) has the .82 4th.

[Marc]

All AHs, including his existing `71, already have have the 4.125:1 R&P. An IRS Type III trans would be a DC (same gearing as the AH).
Early AH with coarse-tooth gears have a .89 4th, fine-tooth is .88.
The .82 comes in Buses and would be a step in the wrong direction here.

The AM is the only stock trans that would offer a benefit.

[Oldschoolblake]

Which ring and pinion does my transaxle use?
As in 6 or 8 bolt, keyed or splined pinion?

I scored a nice complete Spanish made 40 idf with a few extras yesterday! (Don't mind the trade mark)

6075712.jpg

Bought one without a manifold so I'm going to use the aircooled.net premium manifold.
I'm also going to email and see if they can modify the trimil "hot dog" muffler to have preheat.
I can buy the same muffler from socalautoparts.com with preheat but it's the traditional aftermarket exhaust preheat.
I'm wanting to use the #4 flange and plumb the 1&2 side to some other location, just don't know where is a good place for circulation.