Mondial 3,2 with Webers and head porting update | FerrariChat

Mondial 3,2 with Webers and head porting update

Discussion in 'Mondial' started by snj5, Oct 10, 2007.

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  1. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
    San Antonio
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    Russ Turner
    #1 snj5, Oct 10, 2007
    Last edited by a moderator: Sep 7, 2017
    Could not find my previous thread, so a quick update. This certainly will not be as spectacular as the supercharging or V-12 into a 308 thread, but it's a nice little engine targeted not at a max hp number, but at street use in the 3500# Mondial - so, we are focused on reliability, response and wide band power that requires no special servicing. there are component threads on all of the separate systems as they developed.
    To update and recap:

    Head porting: Big news - the heads are done, and going back to Norwoods this week. These have been flow benched and ported using much larger intake valves with a combination multi-angle and radius seat. Peak flow is up about 15 - 17% with an increase in velocity measured on the entire induction system I am told.

    Weber carbs have been uprated to 44 DCNF from 40 DCNF and port matched to the induction. Will have a choice of 36 or 38mm venturis. My current idea for initial jetting is 140/F24/170/55 on the 36mm venturis (smaller venturis are easier to jet for in initial stages - will work up to 38mm). We have two sizes of air horn available - the stock and a chromed custom set that are about .5" taller. The stock Ferrari airbox and side scoop have been opened up to accomodate the largest K&N cone filter available (see old threads).

    Cams - turned out to be an interesting deal after the head was looked at by WEBcam. I chose a less aggressive grind focusing on max lift that would allow the use of the stock drive train and not promote premature valvetrain component wear. Shim-under was looked at, but not really where I wanted to go on this from a servicing standpoint. On WEBcams recommendation, for use with the stock buckets and keeping the maximum torque, the exisiting Speis racing cam profile was chosen increasing total lift @.360 with a rapid ramp, but only increasing duration slightly to keep lower end response. The "area under the curve" on the airflow graph is more than proportionately enlarged with respect to peak flow with large lower opening flows comparatively. She estimates a very wide power band from a bit above 3K to 7.5K rpm, and also well tolerated by the stock valve train components. Not a screamer, but as much torque that is possible.

    New JE pistons are installed raising the static compression from the stock 9.2:1 to 10.5:1 - I am told this will make a very noticible difference. I have an adjustible ignition on mine with MSD, and will be interesting to see if we need to pull the advance back (34@3500) at all with the new compression.

    Exhaust - The Tubi Euro stainless headers are being ceramic coated inside and out and will go to a dual/dual/dual exhaust system: each side will be separate and not communicate, the header collector will split into dual full length pipes on each side, and each side will have two small harmonically resonant absorptive s/s mufflers exiting through separate stainless resonated tips. The entire system will be ceramic coated.

    Details: We'll be going to a Gustafson high torque starter, and am looking at upgrading to a 3 wire stronger alternator per the Consjero system.

    Hope this will be together the end of the month. Extensive A/F and carb jetting tuning with dyno time in November I hope. Thanks to Mark E. for all of his help.
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  2. mk e

    mk e F1 World Champ

    Oct 31, 2003
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    Help me get this thing finished! https://gofund.me/39def36c
    Excellent!

    Now hurry up and post fabulous dyno numbers........so the carbon-copy heads I have will sell quickly :)

    Are you regrinding your intake cams then for a touch less duration/lift but higher acceleration ramps?
     
  3. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Russ Turner
    That's right kids! -Marks ported and polished heads were done alongside mine and will fit QVs and 3.2s!

    Yes - there were some wear issues when she looked at the current cams and then there was that shim spitting thing. I went back and reviewed all of the threads and our conversations on duration, and I am also inclined to think the original Ferrari durations are pretty close for the street. Laurie will take a little off and we'll be around 227@050 with the increased lift to 360 and keep very rapid ramps. With the porting, she estimates the power to peak above the stock (shown to be 6800 on dyno, head limited) to more like 7300. She also feels these will be very safe and durable with the stock valve gear and give a noticable torque jump.

    She also was quite adament that if you use synthetic oil, use Redline to prevent wear. If not, go dino.

    This cam profile was developed by some Ferrari racing outfit she called 'Speis' or something that she pronounced 'Spice'. Yes, I know there are the famous Spice Ferrari V-8 racers, but not sure if these are the same cams and she just mis-spelled their name years ago - it would be cool if they were.

    And, if I get bored, I can always drop in a set of Capo Cams...
     
  4. smg2

    smg2 F1 World Champ
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    Apr 1, 2004
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    SMG
    It's funny what you learn on this site, My cams are stamped with a speis 'a made in Italy' I could not find any info on them, they are slightly longer in duration and about a 1mm more lift. the car always ran with a funny idle, lumpy like a SBC. anyway now i have some more info, thanks Russ. does laurie know more about them?
     
  5. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Russ Turner
    That's interesting - perhaps they were made following your specs or for your car. With K-jet, the increased duration might give a lumpy idle.
     
  6. snj5

    snj5 F1 World Champ

    Feb 22, 2003
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    Russ Turner
    #6 snj5, Oct 12, 2007
    Last edited by a moderator: Sep 7, 2017
    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 betwee 2500 and 4000 rpm.

    If this prediction is good, this should be a pretty nice engine for what I wanted.

    Thanks to Mark E. for running the numbers!
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  7. Countachqv

    Countachqv Formula 3

    Apr 25, 2007
    2,350
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    Question: Where did you get your 44 DCNF from? i am looking for some.
     

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