Maui garage find Intermeccanica rebuild

Jan Peter Stahl posted:

& you should invest some money in a smaller pulley to reduce the fan speed. The original 175mm is way too big for 5000 revs.

usually for more than 4000 you need a smaller one, I would go at least to a 146mm.

and don't worry about the cooling this will not be affected or even better because the stock fan can't handle the high revs anyway.

And check the alternator before you reassemble, usualy after a fan crash it's not in line anymore and ready for the trashcan

I just can say it again also if nobody replied to my post.

with more than 5000 rpms a smaller pulley for the engine builder here in germany is absolut standard to prevent such fan crashes.

Best

For those that have never looked at the cooling fan closely and don't know why it would come apart- the first pic is of a stock type 1 fan. You can see the ends of the blades have little tabs that are bent over but not welded- that physical contact is all that's holding the assembly together. Before you start thinking "kind of shaky", remember that stock fans never come apart in stock engines. As you increase the rpm's the stress factor either doubles or quadruples (I can't remember which) so you can see how spinning it faster would do it in. The design, although perfectly adequate for a stock engine (maximum rpm 4500) just doesn't hold together at 6 and 7,000 (and apparently even 5600) rpm's. Also remember that with stock pulleys the fan is spinning at 1.8 or 2 times faster than the engine- at the redline of a modified engine that's pretty fast! Note that the center is worn- probably not torqued to spec?                                                                                                      

This is a tig welded fan- if not already, it will need to be balanced because of the added material. It will not come apart. It's also brand new- no rust and the center is in pristine condition.                                                 

I think I mentioned it in a post above- I've heard of the tabs being tig'd without using any filler rod (just melting the tabs to the outer shell) so there's no weight increase (I do like that!) and more importantly, the balance shouldn't change.

This is how  a fan is tig welded, it's functional.

OK, Gene Berg welded/balanced fan ordered.  EMPI power pulley, shorter belts, alternator base, alternator (US made), backing plates, shims, spacers, hub kit, woodruff keys, and doghouse shroud ordered. I can reuse the cylinder tins with a little bending. 

I appreciate all of the sympathy sent my way, really. But the kind of person I am, it just seems like an opportunity to make the engine just a little better than before. I'm retired and my granddaughter likes to keep me company while I wrench on things. No worries!

Mike

Bam.

When life gives you lemons, make limoncello.

Yep, and unlike whining, limoncelo can make you feel better. However, there have been times when I was down so long it looked like up to me :-)

mppickett posted:

 

...there have been times when I was down so long it looked like up to me...

 Yeah, I hate wiring under the dash, too.

Sacto Mitch posted:

 

mppickett posted:

 

...there have been times when I was down so long it looked like up to me...

 Yeah, I hate wiring under the dash, too.

 

Just take the seats out, Mitch. Then it's really not bad at all.

Fun with Graphs: Here's a 7 second snapshot of the datalog during which the fan shuffled off it's mortal fins.  I was at full throttle (the white MAP line) at 3777 RPM (the red line on the graph) and the air/fuel ratio was tracking nicely downwards (green line). In the lower graph you can see that the oil temp was steady at 179 F and the spark advance was tracking the RPMs and engine load.

As I was slightly coming off the throttle near the vertical blue line (just the cursor in MegaLogViewer), the RPM continued on up to 5613 RPM resulting in the BANG. You may observe by the white MAP (throttle) line that at that moment I jerked my throttle foot up to my chest and wee'd just a tiny bit, in the most manly way possible under the circumstances. 

40 seconds later I had coasted up the hill, took 2 right turns and coasted to a stop under a big shade tree where I had a very pleasant conversation with a Hagerty agent about the big flatbed tow truck that I needed. It could have been a lot worse.

I learned that the hard redline setting didn't have the effect that it had on my old 911. The Speeduino computer was trying to starve the engine of fuel by cutting the injector times. Duh, I've got carbs. I've since changed the configuration to drop the timing advance to 0* BTDC when it's 1000 RPM before redline. I'm pretty sure I'll feel it and get the hint next time.

Sacto Mitch posted:

 

mppickett posted:

 

...there have been times when I was down so long it looked like up to me...

 Yeah, I hate wiring under the dash, too.

 I've wired dozens of Speedsters.... For big wiring jobs :  Step 1)  Pull the seats & Steering wheel  2)  Pillow, old blanket and a good LED light that will stay where you need it to be. 3)  Wife assists by sitting next to the car knowing what the different wire terminals are and what tools you need.  4) This will at a minimum will require a quality dining experience.

Mike-

With a power pulley and welded/balanced fan, you're good past 7000 RPM _{(at least that's what I tell myself).}

Rods and valvetrain? You're on your own, man.

Mike, on Megajolt they have a spark cut board available. My limiter does the same thing with the advance, pulling it back to zero 100 rpm before the limit. Then at the limit it cuts the spark.

Or, you could always go old-school:

Alan Merklin posted:

This is how  a fan is tig welded, it's functional.

Was there something wrong with the one I posted a pic of?

DannyP posted:

Mike, on Megajolt they have a spark cut board available. My limiter does the same thing with the advance, pulling it back to zero 100 rpm before the limit. Then at the limit it cuts the spark.

Thanks, @DannyP.  Are you using TunerStudio on your Megajolt? If so, cutting the spark is probably an option for me, too.

Mike

Sacto Mitch posted:

 

Or, you could always go old-school:

 

 

We don't need no stinkin' rotors! Nice product, anyway, thanks! 

I ditched the distributor to make room for the AC. A little Speeduino box, Bosch coil pack and a CB Performance crank position sensor took its place. I just have to pay attention to how I configured it.

Mike

@Sacto Mitch I guess that would require a distributor. We don't need no stinkin' distributors!

Mike, I'm running Megajolt software on my Windows 10 2-in-1.

ALB posted:

Alan Merklin posted:

This is how  a fan is tig welded, it's functional.

Was there something wrong with the one I posted a pic of?

@ALB, your welds were too pretty to hide inside of the shroud. Seems like I should be quoting the Bible with something like hiding lights and bushels or something.

mppickett posted:

 

...We don't need no stinkin' rotors!...

...I ditched the distributor ...

...A little Speeduino box...

...Bosch coil pack...

...CB Performance crank position sensor...

You'll shoot your eye out !

ALB posted:

Alan Merklin posted:

This is how  a fan is tig welded, it's functional.

Was there something wrong with the one I posted a pic of?

His is welded on every other tab, rather than hitting every one. I believe he was saying this is adequate, and it might be.

I'd rather not test it out to see. Mine are like yours.

Just so everyone knows- I don't weld. That pic (typically of me) was stolen off the internet.

Stan Galat posted:

Mike-

With a power pulley and welded/balanced fan, you're good past 7000 RPM _{(at least that's what I tell myself).}

Rods and valvetrain? You're on your own, man.

Stan, Inside I've already got a balanced set of SCAT rods, balanced pistons, counter weighted 69mm crank. I looked into ordering HD valve springs and the tool to install and decided I was putting lipstick on an 043 pig.  Instead I went ahead and ordered a set of Panchitto 044 double valve spring heads. I'll still plan to stay under 6000, but won't worry as much about hearing additional bangs.

Mike

mppickett posted:

Stan Galat posted:

Mike-

With a power pulley and welded/balanced fan, you're good past 7000 RPM _{(at least that's what I tell myself).}

Rods and valvetrain? You're on your own, man.

Stan, Inside I've already got a balanced set of SCAT rods, balanced pistons, counter weighted 69mm crank. I looked into ordering HD valve springs and the tool to install and decided I was putting lipstick on an 043 pig.  Instead I went ahead and ordered a set of Panchitto 044 double valve spring heads. I'll still plan to stay under 6000, but won't worry as much about hearing additional bangs.

Mike

Atta' boy, Mike!

mppickett posted:

Stan Galat posted:

Mike-

With a power pulley and welded/balanced fan, you're good past 7000 RPM _{(at least that's what I tell myself).}

Rods and valvetrain? You're on your own, man.

Stan, Inside I've already got a balanced set of SCAT rods, balanced pistons, counter weighted 69mm crank. I looked into ordering HD valve springs and the tool to install and decided I was putting lipstick on an 043 pig.  Instead I went ahead and ordered a set of Panchitto 044 double valve spring heads. I'll still plan to stay under 6000, but won't worry as much about hearing additional bangs.

Mike

An engine that small will never make any where near full use of the potential of those heads- call CB Perf. back, order a 78mm crank and tell them you need 57 cc combustion chambers (8.8:1, .045" deck)...   Your welcome.

@ALB and other gearheads, I need another review of my specs. Boy, they have changed since I started (although I'm still in the modest HP range). Still just looking for a reliable, non-exploding, responsive car for cruising - not going to be racing anybody (except to the last piece of pizza). Thanks! Mike

- 1776 cc engine: 90.5mm, stroke 69mm, piston deck clearance 1.5mm - compression ratio 8.25
- Dual relief case AJ-144762 - Hoover oiling mods
- Full flow oil pump (30 mm ) w/ external oil filter

- Panchitto 044 double valve spring heads, chamber 52cc
- 1.1:1 stock rockers Hoover modified oil passages w/CBP swivel feet
- Cromoly pushrods
- Hardened lifters
- Berg heavy duty grooved rocker shaft
- Engle W110 camshaft .392" cam lift, .430" valve lift (1.1 Rockers), 284* duration & 247* duration at .050", on 108 lobe center

- 69 mm counter weighted crankshaft
- SCAT 3/8 5.40" balanced connecting rods with ARP 8740 bolts
- Balanced Mahle 90.5 pistons and wrist pins

- Dual 40mm Kadrons: 28 venturi, 130 mains, 50 idle (at sea level)
- Ported EMPI intake manifolds (opened up to 1" from bottom)
- Carter P60430 rotary fuel pump
- Holley 12-804 fuel pressure regulator modified for 1.75 psi

- Bosch high output wasted spark ignition module 032905106F
- CB Performance 36-1 missing tooth wheel and Hall effect crank position sensor
- Speeduino ECU spark controller
- NGK BKR5EIX-11 IX iridium spark plugs .044" gap

- EMPI US made 90 amp alternator 9458-7
- EMPI 4099 13 lb chromoly flywheel
- EMPI 1700 lb model 4080 stage 1 200 mm pressure plate
- 5-3/4" Power pulley

- Vintage Speed Taiwan 1.5" stainless sport exhaust system - 155-204-05200 - good up to 125 hp

- Rancho Pro Street IRS Transmission# DC0257471 - 4.125 final gear ratio

What I think- you could safely raise the compression ½ point for that cam. The W110 (or any cam with 245-250° @ 0.050") does well with 8½- 9:1 with dual carburetors and a freer flowing exhaust. Keep the deck closer to .040- .045" so no fuel is igniting on the quench pads and with 50 cc chambers (sharp edges rounded) it will run fine. Instead of chromoly pushrods, hd aluminum are lighter and easier on the valve springs. As I said before, more displacement would work really well here, giving more power (especially in the bottom end/lower midrange) but if that's not on the table I get it. If you're buying a new alternator- is there a reason you're going for the 90 amp unit?

And can you post a pic of the insides of the intake manifolds? We spoke before of taking most of the dividing wall out inside for better idle/off idle performance. Thanks! Al 

Nice combo Mike. You'll love it.

I'll take the pizza...

ALB posted:

What I think- you could safely raise the compression ½ point for that cam. new alternator- is there a reason you're going for the 90 amp unit? And can you post a pic of the insides of the intake manifolds? We spoke before of taking most of the dividing wall out inside for better idle/off idle performance. Thanks! Al 

Thanks, Al. I put in a change order to raise the compression to 8.5/1.

I went for the 90 amp alternator because:

- My ignition switch is wired so all of the lights are on when the engine is running

- I've got a large fans on both the condenser and evaporator sides of the AC

- I've got a pretty big fan on the oil cooler

- I might want to run the house power off of the speedster if a typhoon hits :-)

Yep, I removed the dividing wall on both intake manifolds leaving about 1" at the bottom to smoothly divide the charge into the head ports. Idle is pretty good, but I haven't pulled plugs to see if it evened up the fuel mixture between the cylinders, yet.  Here are a couple of pics, one focused on the top and one on the bottom.

Just curious.......

Does your wife now believe that the madness has consumed you or did that already happen before you found this group?   

Gordon Nichols posted:

Just curious.......

Does your wife now believe that the madness has consumed you or did that already happen before you found this group?   

She's had fair warning about my madness since the our first date when she was 15 years old and I picked her up in my $19.95 1958 DKW Woody Universal Kombi with its 2 cycle, 3 cylinder engine with suicide doors and 4 speed on the column (she could scoot over on the bench seats!). That was about 51 years ago... I don't think I'm surprising her much anymore. 

My DKW Woody (originally baby-crap yellow, rattle can painted in a rat rod motif)

A restored Deke Woody

Not that anyone remembers anymore, but DKW is represented as one of the Auto Union rings that grace every Audi. The other rings represented Wanderer and Horch. 

I guess you remembered and wondered all the way to those islands eh

IaM-Ray posted:

I guess you remembered and wondered all the way to those islands eh

 

That was just one of my crazy ideas that she's humored all of these years.

I would make the deck height NO MORE than .040". With today's ethanol blended fuel and modern head design(Panchito) and a decent ignition system(check marked on that with Speeduino) you should be able to support 9:1, or at least 8.8. 

Honestly, you can get the deck really low, down to .028" with a forged crank and rods and pistons. But .040" is low enough to squish the mixture without getting the parts in danger.

With those CB heads with their nice squish combustion chamber and the precisely acurate ignition, it's a no-brainer.

For those of you interested in what a Gene Berg welded-balanced fan looks like these days. Painted an industrial green except where material was removed for balancing, I assume.

The stamp says PRUMSA

Shiney edges where material removed

Nice. That looks like industrial paint for sure, ewwww is the color name!

Mrs. Berg must have been able to score a bucket left over from an elementary school cafeteria. See, that goes with ewwww, too.

@ALB concerning the opening up of the EMPI Kadron manifolds and the impact on fuel mixture, I pulled the plugs. Here are some pics - this is after idling about 30-40 seconds after a strong pull to 5600 RPMs.

Parts are trickling in. I nearly have everything to replace the fan-damaged parts and to beef up the tolerance for RPMs over 5K. CB Performance will be setting up the Panchitos for 50 cc chambers before they ship. They're running with reduced staffing to allow for increased distancing between employees. 

While I wait in line, I pulled the old heads and checked the deck and it turned out to be .040" as it should have been. With 1776 cc and 50 cc chambers, I should end up with 8.9 compression. I verified that with Marieanne at CBP and she says that's in the sweet spot for the heads. 

I finally received the replacement alternator. I ordered the normal finished 90 amp U.S. reworked EMPI. It was hard to find, but the other option was chrome.  I got a good price, and it arrived yesterday, in chrome. I guess I'm going to like chrome 🙂