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3.2/qv performance cam specs - wow

Discussion in 'Technical Q&A' started by snj5, Mar 25, 2004.

  1. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
    San Antonio
    Full Name:
    Russ Turner
    For all of your racing spec archives or those following the Weber 3.2 saga, here is the note from Dema Elgin with the specs to the intake cams he will be sending me; He is currently straightening and finishing and we hope to install these beauties in April.

    Pasted:

    "Hello Russ, Here are the specs of your stock cams -vs- the modified welded grind. The std cam has 250 duration @.018"=ramp end and now they will be 264 @.014"ramp end. std @.020=245 vs 257, @.050=222 vs 238 @.100=200 vs 214 @.200=151.7 vs 166 @.300=83.8 vs 103 lobe lift std=.345" mod=.364" .364 less lash of about .012" =.352 net valve lift. As you can see the new profile will have a lot more area under the curve which may require a little more fuel along with the increased air flow capabilities."

    Paste off

    Well, I'm excited to say the least; I'm running 36mm chokes already (max size for a 40 DCNF) which should (according to Pierce Manifolds) accomodate well over 300 hp; Have lots of room on the jets obviously. He added a more duration and a lot more area lift.

    With stock cams I am now dynoing 236 SAE rwhp (~288 crank) since the Weber installation. Any bets as to the new max?
    I asked him about drivability - he said that they would smooth out about 500 rpm later than my stock. I told him my stock were pretty smooth all the way through, and he replied about 1500 then.

    Pretty cool, huh?

    best to all
    Russ
    (Carlo Abarth wannabe)
     
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  3. Ed P.

    Ed P. Formula 3

    Dec 28, 2002
    2,177
    Long Island
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    No Longer
    Russ is cool!
     
  4. chrismorse

    chrismorse Formula 3

    Feb 16, 2004
    2,149
    way north california
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    chris morse
    Russ, the #s look good from my miniscule experience. It should sound good too. What exhaust are you running??
    chris
     
  5. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
    San Antonio
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    Russ Turner
    Chris
    The engine now has the factory US spec headers with a Stebro resonated "test"pipe replacing the single cat. This leads to US spec single inlet Tubistyle muffler.

    I had SERIOUSLY looked at going to a true separate exhaust system or a Larini Euro system, but Tate at Carobu and Mike at Norwoods both said that they did not feel I would gain that much (a couple hp) over the Stebro/Tubi and it might sound like a ricer. Not enough bank for the buck and modifications that might be neccesary. I am looking now at placing resonated tailpipe tips on the tubi to bring the sound down a bit to better suit my requirements. Leaving it this way I can always put a cat back in easily if that ever is a concern.

    best
    rt
     
  6. chrismorse

    chrismorse Formula 3

    Feb 16, 2004
    2,149
    way north california
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    chris morse
    Russ,
    I am still curious what a Tubi sounds like. I completed the 'low dollar' flowmaster exhaust system recently, with resonator tips, and took your advice and installed 140 mains and 200 AC's with the K&N filter. I dropped the air pump belts and the low speed points as well.
    Yesterday, I had a bung installed in both header pipes, (lucky me), sorry, it's getting late. I received a digital AF meter from Wayne and am all set to go except I cannot get the cigarette lighter out. It looks like the center of the lighter is missing, or does the 308 have a 3/4 inch skinny lighter. When I pull on it, the whole thing wants to come out of the console, and as I have enough things on my list, I was a bit hesitant to start disassembling the console - lord knows what that would lead to - if you know what I mean.
    With the new jets and the low speed points disconnected, a lot of the deceleration rumbling, banging and popping have disappeared.
    I have not yet checked the timing or dwell - the power is very good.
    I am guessing that it is a bit rich at idle, the mixture screws are all backed out about 4 and 1/2 truns, is this normal???

    thanks,
    chris
     
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  8. pma1010

    pma1010 F1 Rookie

    Jul 21, 2002
    2,559
    Chicago
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    Philip
    Chris
    Cigar lighter is somewhere between 3/4 and an inch in diameter.

    If you need to remove the whole thing, it is an easy pull on 308, assume 328 is similar. On a 308: Remove ashtray. Remove 2 screws exposed by the ashtray, "flange" Or "tongue" with all the controls can be levered up a couple of inches (be careful not to over stretch, you'll kill the fan switch). Cigar lighter has a threaded sleeve which unscrews from beneath the "flange" and disconnects with a push type connector.

    US idle mixture screws have a "shoulder". Typically work 2 - 3 turns out. More than this (or less) usually suggests a different jet.

    Russ,
    I have a bit more work to do on the sync'ing and idle mixture. However, here's some initial data running 36mm venturis on 44 DCNFs with 150/F36/60/165 (main, ET, Idle, AC). If I recall correctly the pumps are 45s:
    - I am seeing steady partial throttle AF ratios of 12:1 at 3000 and 13:1 and 4000 and 5000. Will work on the idle (see below) and then re-test. Also need to see where it is at 6000 and 7000 with Weber's full power test (accel and brake)
    -Hot Idle 12:1 (the P6s will make it run fat, but assume I can get closer to stoich)
    - Slight accel is going lean on transition to main (3800 rpm). Likely ET is going to need some work. (I also have a set of F30s but need to go back to the tables)
    - Hard accel, first, second, third gears 10.7:1 - 10.9:1 after initial transition.

    Bottom line as you can see is it is rich across the range and costing me a lot of power. I'll start by re-doing the idle mixture and then getting the balance done. From there I'll post more data. Will also look at some dyno time before Road America in May.
    Philip
     
  9. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
    San Antonio
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    Russ Turner
    Chris - do you have a recording of your flowmasters? I am wildly curious to hear yours as well. Perhaps even over a cell phone?

    As Philip suggests, with the 140s would look at coming in a bit on the idle screws.

    I need to get one of these A/F doofers from Wayne this week. They clamp on the tailpipe well?

    best
    rt
     
  10. snj5

    snj5 F1 World Champ

    Feb 22, 2003
    10,213
    San Antonio
    Full Name:
    Russ Turner
    Agree should start with idle to .55. That 60 is the root of your full spectrum richness.
    I like F24 ETs - a bit more personality than the F36s
    I think what will be close is a 145/175 with the 55 idles - perhaps even a larger A/C. This should give close to high 12s - mid 13s across the band wide open and even pleasantly lean it out a bit at cruise. When you do your dyno will be interested to see 'tip - in' behavior when you dump the throttle.

    best
    rt
     
  11. 4re gt4

    4re gt4 Formula 3

    Apr 23, 2002
    2,279
    Roseburg, OR
    Full Name:
    Hans E. Hansen
    Cigarette lighter sub-topic: Early 308s have a 'Euro' style lighter. It doesn't pull out. You push down on the rim of the lighter, and insert the cigarette into the hole.

    It doesn't lend itself for use with power accessories.
     
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  13. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,804
    Houston, Texas
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    Bubba
    It's tough getting the short ones back out, also.
     

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