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Author Topic: engine has no power  (Read 8959 times)

Offline VileZambonie

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Re: engine has no power
« Reply #15 on: March 10, 2008, 04:26:39 pm »
What do you mean flanking your pcv hose?  ??? you can hook it up either way. I prefer manifold vacuum at idle to vacuum advance. You should have vacuum at the modulator also.
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Offline SUX2BU99

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Re: engine has no power
« Reply #16 on: March 10, 2008, 05:26:32 pm »
I mean I have 3 ports on the front of my carb. Big one in the middle and two on either side of it. I keep hearing about timed/non-timed and ported/non-ported vacuum ports. I have no idea what means what, but I'm wondering if the ports on the carb make any difference.
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85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline VileZambonie

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Re: engine has no power
« Reply #17 on: March 10, 2008, 06:17:23 pm »
Ported or timed means there is no vacuum at that port while the throttle plate is closed. When the throttle plate opens it exposes that port to manifold vacuum then receiving a vacuum signal. So it only receives vacuum when the throttle is open.

The other port is manifold vacuum.

The large front port is for your PCV like you have it.
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Offline SUX2BU99

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Re: engine has no power
« Reply #18 on: March 11, 2008, 12:05:42 pm »
Ahh I see. Well I just learned something new. Thanks!
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85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline Cowboy_Customs

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Re: engine has no power
« Reply #19 on: March 11, 2008, 02:21:44 pm »
Quote from: plowking_90 on March 09, 2008, 06:17:30 pm
i did the turn the wheel thing to calculate the gear ratio and  i think its a 411 not possitive though, but even if it was stock gearing i have 350 hp it should be like butter on my tires with the 31's

how are you so sure you have 350HP? No offence but just wondering how you know this for a fact. If you did the driveshaft rotation, versus wheel rotation, calculation, and came out with something close to a 4.10 I would believe it. Have you checked your vacuum advance? I had the same problem on my 78', the advance diaphram was bad so no power at all.

What year is the truck? What transfer case do you have? What kind of RPM does it turn at around 60MPH? Your positive, 100% sure the 4wheel isnt engaged?
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Offline SUX2BU99

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Re: engine has no power
« Reply #20 on: March 24, 2008, 03:35:46 pm »
Hey Vile, does it matter which kind of vacuum the modulator is seeing? I downloaded the Performer owners manual and the passenger side port is ported and drivers side is manifold vacuum. I know you said it doesn't matter too much about the vacuum advance canister, but does it matter for the modulator? I suppose it shouldn't since vacuum is available at both ports as soon as the throttle is opened eh?
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85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline VileZambonie

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Re: engine has no power
« Reply #21 on: March 24, 2008, 03:40:35 pm »
Transmission vacuum modulator should have manifold vacuum
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Offline SUX2BU99

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Re: engine has no power
« Reply #22 on: March 25, 2008, 11:58:43 am »
Cool, thanks for the info.
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85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.
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