3.2 ported/big valves/carb first run video

Received the muffler assembly back from the ceramic coater today. While the headers are stainless steel coated in the silver, the stainless steel muffler and piping are ceramic coated in flat blak as not to look to "blingy" from the rear. The tips are polished stainless. While the muffler coating is primarily for protection (and not show heat discoloration as on tubis), it should also act to heat insulate and keep the exhaust velocity higher. You can also see the bung where the LM-1 O2 sensor will plug in to monitor Air/Fuel ratios as the carbs are tweaked.

Next comes finishing up with carb synch, tuning and dyno.
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The ceramic coated stainless steel muffler is installed with the new lightweight rear valence. I really think the wider stance on the exhaust looks terrific - a definite improvement in my eye to the stock narrower spacing.
Next comes the exciting part - driving, tuning and the dyno.
As always, many thanks to James and the team at Norwood's
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I think this is good advice. We did use all new hardware/gaskets, but I will sure be careful as we dial this in with the O2 sensors. I wanted to make it convienient to take them in and out often , even though the header is the more reliable (if harder to use) location.
thanks
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After many months, the Mondial is back on the public roads. The carbs were just roughed in to take a brief low speed test drive, check shift likages, check for rubbing, leaks, etc.It perhaps may not be as quiet as hoped, but still too early as no speeds above 3000 rpm. James said the biggest impression, even this early on, is a VERY crisp throttle response. Mark and I had hoped for this with the flowed heads with a very high port velocity and the 10.5:1 compression pistons. This is very hopeful as the possible problem we might have with the relatively large 44mm carb and 38mm venturi is a lack of throttle crispness due to loss of velocity - so far then this seems to be doing well with good response. This will also perhaps be improved once the air horns are installed.

As you can see, it's not running with stacks, airbox or bonnet lid, so I imagine it is quite loud. Next comes dialing in the whole package and hopefully a dyno after a couple hundred miles break in and A/F tuning.

And again, I really like the widened exhaust.
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Mark - In my experience it will change it only minimally between stock air horns, not as sure with the new taller ones (if we use them); but somewhat larger changes are had between running open as shown and running with the complete airbox and filter. I have seen the AF curve shift 0.5 to 1.0 richer over open carbs once an air box/filter are in place, with the largest changes occuring with the stock GTB/GTS airbox with the restrictive filter set up before the wadding was removed. With the new high flow airbox mod using the cone K&N I don't know yet, but empirically, the less jetting changes occur with less flow restriction -- we'll see in a week or so.
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Bill - Many thanks.
The individual vacuum lines sound good, and will check into this.
Speaking of vacuum lines, one of the interesting things was that with this car having ABS, NO vacuum line was needed to be drilled to provide for a power brake booster as the brake system has its own booster. The only vacuum line needed was one to power the HVAC selector switch; the ignition vacuum was not needed as I went to the electronic distributor without vacuum advance.

It's pretty sure that some possible higher end hp was traded for the lower end by keeping the near stock camshaft durations, but it was always the goal to have the best street GT engine for daily use. Another interesting point was that to add any more lift or duration to the new camshaft profile would have necessitated shim-under followers to avoid any long term cam wear/reliability issues.

So, all of the components are specifically matched: The head is ported to get maximum flow volume (i.e. no restriction to) and flow velocity from the induction, the larger intake valve optimized for flow velocity in more correct proportion to the exhaust flow, the camshaft lobes are the most that can be run reliably with the stock shims/followers, the 7300 peak power band of the cam durations match the flow characteristics of the 38mm venturi as applied to a 400cc cylinder, the 44mm carb provides the optimized match to the venturi size for vacuum signal, the 10.5:1 compression ratio pistons are about as much as you want to run on street gas safely, the tubi headers are optimized for a wide torque band, the separate dual exhausts are optimized for the flat crank exhaust pulses and so on...

Hopefully it all actually works...
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Not much news while on a work trip to Virginia for a couple of weeks. I know that James is beginning to drive it a bit to begin engine break-in, and will initial dyno next week. While this is new ground, my experience is that this first dyno will be quite shy on the final output numbers as one dials in everything. And while I know the Dynojet numbers are SAE temp corrected, the 100 degree ambient Texas summer air temp just doesn't help the numbers.

Remembering that my previous base maximum qv head flow with 40 DCNFs was about 92/93 CFM @10" at .348 lift, and generated best numbers SAE corrected measured of about 238-242 rwhp @6500 and 203 ft-lb torque ( using std 17% driveline loss, approx flywheel numbers of 286-291 flywheel hp and 245 ft-lbs). The new (and final) flow numbers after the head re-profiling for better lower lift flow are:
.100" 42 CFM
.150 69
.200 87
.250 97
.300 102
.350 104
.400 105

So, it's hopeful to note that we are already past the max flow at the stock max .348 lift by a lift of .250; although the flow max CFM is only up by 11 - 12% it all comes in much earlier and for a longer time. Couple with this as said before remarkably increased velocities over stock. So while I do not think the dyno number will be quite as high as would have been seen with the .400 cam, I will gladly trade that for maximum reliabiity and wear characteristics.

Based on going with the consevative cam recommendation from Laurie at Webcam for reliability, Mark E. ran the numbers in his development computer using the data from the new cam. The complete Speis cam profile is as follows:
Valve lift .360
Duration .010 280°, .020 248°, .040 232°, .050 226°, .100 202°, .150 180°, .200 158°, .300 96°

The peak numbers look to be about 340 hp at 7200 rpm with a peak torque of 260ft-lbs. Mark thinks the booble in the torque curve is artificial, and the line should be smooth between 2500 and 4000 rpm.

The first dyno attached is a real-world REAR WHEEL HP numbers with stock head and cams and JUST the Weber 40mm carbs as compared to a stock 3.2 liter K-jetronic injected engine.
The second dyno is Mark E.'s computer sim showing PREDICTED FLYWHEEL HP for the new head, new cams and the 44mm Webers. If we are EVEN CLOSE to Mark's numbers, I will be thrilled - I am shooting more to be close to the 320 hp (the magic 100hp/liter) target.

I'm hopeful for a good top number, but it will be the torque curve, drivability and reliability I am really targeting.
Hope this is entertaining for six guys still following this.
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While I am away on a trip, James at Norwoods is breaking in the car. The carbs are close and he says better than he thought for an initial jetting. He says it pulls very strongly, much more noticible than before, and he has been keeping to 5000 rpm and below as the rings seat in. He says that he feels the car is at about the 80% tuned point, and very streetable as is.

He says to really do the induction better, the filter needs to be closer to the cold air duct than it is now. He will take some mandrel bent sections and weld in sides to keep the ovoid duct shape and pace the intake closer to the cold air. When I asked him about using an 'Aeroquip' type hose he was adament that all flexible hoses and unions killed airflow, so we are doing the hard shaped mandrel duct for max airflow velocity. He said he would get this done in the next couple of days and plan on the initial dyno next week after some more break-in miles.
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The new improved airbox turned out pretty cool. As we discussed earlier, the goal was to place the largest K&N cone filter closer to the cool air duct, yet leave a little room for weather run-off and cool air to circulate up arund the carbs and engine "v". James also relayed that any flexible hose or coupling acts to restrict laminar flow, so we extended the increased diameter air box snout with smooth metal bends.
The pictures show how it smoothly ducks and dives to the starboard air scoop, which itself is now fully opened after removal of the plactic ductwork and silencer. The second photo shows the enlarged airflow track directly to the air horns.
The completed piece will be cleaned up and fiisned in oven baked crinkle black.

The car is breaking in well so far, and the initial tuning dyno is hopefully set for Thurs/Fri of next week. James is also expecting a very good low and mid-range punch with terrific throttle response based on his test drives so far.
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Here's a view down Happy Valley before we close it up showing the really nice center pull Heim joint linkage James made - it's much better than the previous side pull. This engine is just so great looking.
Will finish up some things next 2 days, I'm told we are scheduled for first Dyno on Monday. That should give us about an idea of where we are going.
Thanks everyone, especially MarkE, for all the help over the past year - wish us luck!
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