LT4 hot cam, Vortec heads, Carb timing??
#1
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Location: Wisconsin
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Car: 1987 Trans am
Engine: 350 TPI
Transmission: 700R4
LT4 hot cam, Vortec heads, Carb timing??
I did a search but really haven't found anything. Who ever is running a hot cam, vortec heads and a carb can you tell my whats your timing set at. Intital and full advance.
Thanks
Thanks
#2
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34-36 for full should be enough.
Play around at the track though and keep at set full at what produces your highest trap speeds.
Who knows maybe your pointer is off so it always best to go with what is fastest.
Play around at the track though and keep at set full at what produces your highest trap speeds.
Who knows maybe your pointer is off so it always best to go with what is fastest.
#3
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I have the exact setup you have. 18 degrees initial with 32 total. I have a 750 Edelbrock on a 5673 GM manifold with the HOT cam and vortecs. 26-27 mpg on the highway at 70mph with 5 speed Tremec and runs 13's with 3.27 rear gear. I have a distributor respring kit and am using 1 heavy spring and 1 light spring. I tried 36 degrees total and it worked ok for street but when I threw the drag radials on it it would knock because of the extra traction. With street tires on it for just cruising I run 87 octane and it does not ping ever-great combination.
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Car: 88 Firebird
Engine: 350 LO5 TBI
Transmission: 700R4 Vette Servo/Shift
hey rangelec did your setup require any drilling or work on the vortecs? Im guessing thats the GM vortec intake did it fit well? what did you do for the 750 carb...adapter plate to fit the 5673?
#5
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I pinned the studs with roll pins, cut for springs but you could use a different spring that would fit into stock cup, 750 bolted right on to the manifold-it resembles the LT1 intake and is made for a Holley pattern. I had it out a couple of weeks ago with street tires (235/60-15-nothing sticky at all) and with 3.70 gears it ran 13.34@106mph-should run 12's with drag radials.
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Car: '89 IROC-Z
Engine: Canfield 195 headed 358ci
Transmission: TH350, Art Carr 9.5"
Axle/Gears: 3.92 Dana 44
I'd start with 32* total and as much initial as your starter can possibly crank over. Vortecs seem to work best with less total timing.
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