Mondial 3.2 ported/polished head/big valve/big cam/header upgrade

Thanks - I am a big fan of your folks intake manifold projects as well; they are quite inspiring.

 

There is an inexpensive dyno sim available at Barnes and Nobles called Desktop Dyno SE. I punched in the parameters of the information we have on the ported headflow and new valve sizes and using the current Webcam intake cams and stock exhausts got numbers similar to Mark and Vic's more accurate dynos, which is re-assuring. I do think the Desktop Dyno numbers are a bit high, but it interesting that they did not show a sig. increase in hp from going from .368 lift (current) to .400 lift (proposed); Of course reality is always a bit different.

Desktop Dyno (lift 368, intake duration 235):
rpm hp tq
2000 76 198
2500 98 205
3000 121 211
3500 153 229
4000 196 258
4500 236 275
5000 267 280
5500 293 280
6000 313 273
6500 327 264
7000 340 255
7500 346 242
8000 350 229

Using the stock 328 camshaft (lower duration @ 220, lower lift at .348), here are Mark's numbers with the ported head and new valves:

rpm hp tq
2000 71 187
2500 94 197
3000 112 197
3500 141 212
4000 174 228
4500 205 239
5000 233 244
5500 258 246
6000 287 251
6500 318 257
7000 345 259
7500 347 243
8000 346 227

If even vaguely comparable, it is interesting the effect of the difference that a little more lift and duration make on the top end.

Interestingly, the peak hp numbers are not too dissimilar from Nick's 3.5 liter 2v dyno and on the Carobu site, suggesting why Ferrari went to 4 valves.

While I think all of these numbers may be a bit high, they are hopeful.

Will hope to have more accurate computer sims from Vic's equipment later.

best to all

rt

 

Here are the two computer runs adjusted for 17% rear wheel hp loss to compare to the current car.

The current car has Webers, stock heads, stock exhaust cam and the intake @ 0.368 lift 235@50 cam. These are the grey lines on the graph from a real world Dyno-jet chassis dyno.

Mark E's computer sim with ported heads, stock 3.2 exhaust cam, with stock 3.2 intake (0.348, 220@50). These are the maroon and blue lines on the graph, and are probably close.

The Desktop Dyno computer sim is with ported heads, stock exhaust cam and the 0.368 lift 235@50 intake cam - this is the bright red line.

While I like the boost in upper end, the midrange boost, or at least NOT LOSING torque in a 3500# car was what the primary goal was.

As I said, things are hopeful, but these (except for the current real world Dynojet numbers in grey) are just estimations.

I'll post a finished Dyno-jet when we are done to see how close we came.
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Some of this was discussed in two supporting threads on compression and calculating carburetion among others.

Heads/manifolds: new valves being finished up, will post flow numbers soon, but hopeful of bringing flow up to 112 CFM for an increase of about 20%; The heads could have been ported for more flow, but this is the max flow with the max velocity critical for low end. Any more porting showed a decrease in velocity on the practice head, so we are going for max flow with max velocity intersection. This requires a lot of flowbench work, so many thanks to Vic and his perseverance.

Cams: Laurie at Webcam is making a new master lobe for this application to provide max lift for a qv or 3.2 with a slightly longer duration; looking at around .400 and 230 or so @050. Did not want wompus duration so to keep low end torque.

Carbs: Short story is after porting, the 40mm carbs were a restriction; using calculations shown in the Carb requirements thread, a set of NOS never used 44DCNFs found & purchased in Oz. Starting point: Air corrector jets 170, Main jets 150, Emulsion tubes F36, Idle jets 57 and the venturies are 36. Wire transfer went through today, so hopefully Vic will have them in a week to flow them and port match to manifolds.

Airbox - will be using a slightly uprated version of the twin airbox system I have now. The carbs did not come with air horns, but found NOS sets cheap (!) for 44DCNFs at Gene Berg Volkswagen Parts (!!!). I am also modifying a stock 308 airbox as a single plenum ramping to a single K&N Throttle body oval cone air filter - RF1001 - the largest they make. It will sit in an enlarged custom aluminum duct brought off the starboard side scoop. Not sure which airbox to finally use, but the decision will be based on hp cost and sound.

Headers/exhaust: new tubi headers are off to be ceramic coated inside and out; the custom dual exhaust with Ferrari TdF layout pieces ordered and 90% arrived. See the supporting performance exhaust threads for discussion.

Compression ratio: after a good discussion in the 'how much compression for the street ' supporting thread, am teetering on bumping up compression since we have come so far with everything else. To quote Frank Capo "It'd be a shame as you've done everything else right" -- but of course he's not funding this. The balance is how much compression will stay safe with pump premium gas. It would be easy enough to do 12:1, but it would then be easy to hole the piston. Right now am looking at 10:1 or 10.1:1. the good thing is it would be mostly felt down low, and beefing up the bottom end is more important than actual peak numbers (this is a 3500# Mondial, after all).

Suspension: Mounted the new Pilot PS2 on the previous 17" Speedline rims using 205/55-17 and 235/50-17 on the rear, which will functionally reduce the final drive to about 3.82 to one from 4.01 due to the larger tire. The section rationale was also discussed on several supporting threads. The rear ride height will be brought down .3 - .4 inch to compensate for the taller tires.

Interior: A pet peeve of mine, the Mondial headrests are terrible especially for a tall guy. Am having a set of taller headrests made in matching leather, much like the TR headrests that cock forward at an angle so they actually work. If you do not think I am OCD enough by now, I did find a contemporary NEW Momo Cavallino 1 with white stitching (Ferrari key point here), from FChatter Calvin Crouch who sells and has a personal inventory of classic Momo wheels (how cool is that!).

Garage sale items so far:

Michelin Pilot A/S: 225/50-17 and 245/45-17
Momo Prototipo wheel with silver spokes
40DCNF-12 carbs (already had interest)
Stock 3.2 US headers
Really nice sounding Ansa/Dynomax free flow exhaust system for same

All comments or advice welcome!!

 

That coming from a guy with a 600 hp 308...who's out of control?

 

Here are photographs of the two airbox options.

The first two show the current 'dual plenum' airboxes, while the third is the new single plenum using the original Ferrari airbox prior to being finished and powdercoated in wrinkle black.

You can see in the second photo how the opened up side vent floods the two filters and carb area with cool air while moving.

Any and all constructive advice welcome.
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It still is a 3.2!


James at Norwood's uses JE and has several piston profiles on file with them. I am looking also in the 10:1 to 10.2:1 range. We'll be figuring out If we can do this next week. I know the stock Euro 3.2 uses 9.7:1. Just an intuitive feeling, but if a compression bump is mainly felt in the low rpm range, and the gas octane is available, I would think this would be especially good on a Mondial. I'm just not sure about gas quality required when the compression ratios are raised and the cylinder pressures start really getting high.

 

Well, after discussion in the suporting thread on compression ratios, I talked it over with Tate Casey (Carobu) and James Patterson (Norwood). While many cars may tolerate 11:1 on street gas, a consensus was that 10.5:1 should be quite safe on street premium with stock or near stock advance due to the efficient combustion chamber design.
Norwood's has some profiles on file with JE, so will be adding a set of 10.5:1 pistons to the mix, up from the listed stock compression of 9.2:1.

So - recap:

Ferrari 3.2 liter 4 valve
44 DCNF Webers
Ported/polished heads
high lift 0.400 cams, sl increased duration
big intake valves
10:1 compression pistons
Tubi s/s Euro headers
dual flow through exhaust

As a tribute to one of my favorite Le Mans winning historic racing Ferraris, I'm thinking about calling my car a Mondial 3.2 Plus.

Thanks to everyone who participates in the support threads!

 

Hmmm - could you go into a bit more detail on that? That sounds very interesting.

 

The 44 DCNFs sourced from Australia are on the way. The stock settings that come with this carburrtor are:
36 mm venturi
150 main
F36 emulsion
170 air corrector.
57 idles

Spares: 34mm venturis, 145 mains

Had a lng talk with Mike Pierce at Pierce Manifolds today - he thinks they are probably spec'd to a Ducati. While we will tune this on the dyno and with an LM-1, he feels the final jetting will be around 145/190. There is a concern on needle valves - will need to check as if they are 175s, we'll need to spec up to 250 or 300 for the required flow.

S0, the jets we will take to the dyno in addition to what is is already there:

140 mains
190 air correctors'
F24 ET
55 idle
52 idle

All advice welcome!

 

Talked with Mike at Norwood's today. Once we get the car built, I am going up to Dallas and we will jet and tune the car together on the dyno with my Little Box of Weber Magic. This is yet another reason why Norwoods is truly a superior place to go and worth extra is the customer service.

That all said, as it gets closer, if any carb car folks are interested in watching along as we develop carb jetting from scratch and tune on the dyno, let me know and perhaps we'll do it together.

The initial phase at first startup the carbs will be sync'd and first A/F strengths will be done in the shop using the LM-1 with probes in the exhaust. We'll then move to the dyno where we will tweak the car under full load. Then the drive back the LM-1 will allow us to fine tune the 'running' A/F with final adjustments.

If you have a wideband O2 bung placed in your exhaust for a few bucks at an exhaust shop before you get there, we'll see if we can place the LM-1 on your car and check your mixture on a drive, and possibly tweak your jetting. I think you (especially you guys with 60 idles ) will be amazed at what your A/f actually runs while driving.

 

the engine out and being cleaned;
New JE 10.5:1 pistons ordered
Waiting on ported heads, matched manifolds and carbs.


We're gettin' there....
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Earlier we did some research on if the 360 crank would fit in the 3.2 block; the definintive answer is yes, but requires a custom flywheel and some milling of the nose shaft. If used, it will bring the displacement of a 3.2 liter engine to over 3.4 liters. There are some custom cranks around, but are quite expensive and require a long lead time.

So, for me it came out cost and time ineffective to stroke the engine. We are still hopefully targeting over 320 hp and keeping a strong low-end torque with what we have, so we'll keep it simple.

Carb & induction news

Based on what I can tell, the carbs are indeed 44 DCNF-107s from a Ducati and fortunately have the required 300 needle valve. This set **in theory** should support well over 340 hp.

WEBER 44DCNF 107
Main data:
Main Venturi 36 mm
Auxiliary venturi 350
Main jet 150
Air corrector jet 170
ET F36 **(I will be swapping to F24s)**
Idle jet 57
Idle air jet 130
Pump jet 35
Starting jet F7/110
Needle valve 300
Mechanical float level 46 mm
Float weight 14 gr

I have now three sets of air horns - the Kermit 1/2" low rise, the stock 1.5" mushrooms and the 1 7/8" Berg talls stacks. The stock airbox has an internal height of about 2 7/8", so **in theory** they all should be ok leaving the recommended 3/4" open space above the bellmouth. Will probably use the mushrooms or the Bergs depending on what the dyno says.

The ultra-high flow airbox mod is about done to further reduce the inlet restriction and smooth the airflow to an even greater degree than the standard airbox high flow mod. It is really just the next step after Spasso's nice elongated fiberglass snout airbox, just opened up a bit more and done in metal. It's being powdercoated this week. Will post a photo of work in progress.
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Weber 40 DCNF-12s and the linkage pieces are not uncommon to pick up at Weber stores and on Ebay - would recommend you simply re-jet them to 140/F24/190/55 as a starting point.

The carb manifolds for a qv are more of a challenge. Would talk to Modena Engineering in Oz - they did mine. It may be just as inexpensive to build one in a quality fabrication shop. Sponsor Nick of Forza Ferrari once mentioned he would be doing a set as well.

Good luck!

 

Quick update on the high airflow velocity airbox for the ported/polished high compression 3.2 QV engine for the 2 or 3 OCD folks like me. Have completed the prototype with removal of 1" all the way around to eliminate the increase in area and volume the air column would see as it entered the air box. It's much like head porting - air flow picks up flow and velocity as the path narrows but tumbles and gets in it's own way going from smaller to much larger area/volume. The box recieves air from the largest K&N oval cone filter made which recieves cool outside air from a high flow open duct from the starboard air scoop. While this design is more effective while the car is in motion rather than sitting still, there is a greatly needed benefit of flowing cooler outside air down the "V" of the engine to keep the carb temperatures down.
Interestingly, the welder on his own decided to take it out of the inside and bring the stock walls in rather than just cut and build a new sidewall. The stock lid was narrowed and side lip re-contoured to match. The effect is that it is only subtly different appearing than stock. It'll now get cleaned up, media-blasted and black crinkle powder coated.
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If you look at the stock 308 airbox and scoop objectively, flow obstruction occurs in a couple of places. Remember this system was designed to work for the mid 200 hp range and be quiet.

The stock scoop turns out to be a bit restrictive on it's own, with only a small fraction of the total scoop area being ducted to the engine. If you look at the rubber hose, there is flow resistance from the bending and texture.
The airbox has a fairly narrow apeture where it meets the hose, then it narrows a bit more due to the sound insulation. Then, the largest obstruction is the well documented closing off where this muffling obstructs most of the stock filter (see very long thread on this: airbox obstruction discovered).

While removing the noise abatement packing increases flow dramatically, the airbox limitation then becomes the small inlet apeture and the immediate enlarging of volume which causes the airflow to tumble on itself and adds a functional flow restriction.

I'm aniticipating a quite large flow increase with the new system as all of these issues has been adressed (in an over-the-top kind of way, I will admit). That particular K&N is about a 400+ hp piece.

If I were to recommend more reasonable changes based on my research for a 'normal' 308, it would be to do the sound packing removal if appropriate, them cut off the open box snout floor and weld in a flat floor to smooth out the air flow - at the same time I would recommend to enlarge the inlet apeture and go to a larger and smoother duct and vent directly to the scoop. The final phase would be to duct this larger hose to a large K&N cone filter (like the supercharger guys are doing) that sits in the duct opening and do away with the stock filter altogether. It would look basically stock and significantly outflow the original equipment I believe.

As I've said, I've taken out some of the capacitance of the original box volume which is a more theoretical thing and also continues the application of head porting principles to the airbox - we'll find out. The other thing I am trying to do is get some cooling air to around the carbs in the engine "V" to help reduce the fuel temps - this had been a problem for me here in San Antonio which went away altogether with the larger scoop. I may have a slightly warmer intake charge at full stop, but once the car is moving the engine compartment is flooded with outside air - a trade off worth it to me. K&N alao makes a weather sock to go over the filter if more protection is neccesary, so pretty handy.

best
rt

 

Well it seems the new restriction in the induction system now that the heads are ported may be the carburetors. Even with the larger 44DCNFs, the head and cam now may outflow the carbs. I suppose I could go to a yet larger carb or throttle body, but remembering that the idea is not the biggest number at the top end, we may be ok. While I may not make some wild ass huge high rpm hp number, the original goal was to have a much beefier lower end as this is a heavy 3400 pound street car. Realistically in real world driving most of the driving will be below 7000 rpm.

Using the widely available Weber venturi selection graph, we'll try to predict about where we will fall out. Using the graph shown, for the largest available venturi for the 44 DCNF, a 38 mm, the rpm max flow (hp) occurs for a 400cc cylinder (as in a 3.2 liter V-8) conservatively at about 6600 rpm. So the max hp will asymptotically approach and level off at this level. If we apply the restriction to the previous computer flow model of this engine with a 10.5 compression ratio (the blue line) it says we cannot produce more than about 280 rear wheel horse power, and also in the ballpark suggested by other computer sims and the original baseline run on 40 DCNF with 34 mm venturis and a non-ported head..

While not as much as hoped, the stronger bottom end as main desired effect still looks to be there - we'll see in a couple of months.
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