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Old 07-04-2012, 11:15 AM
rootdmann rootdmann is offline
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LT1 Carb intake

I have an LT1 with a carb intake in my chevy c30. I'm actually thinking of converting it back to fuel injection using a megasquirt. I could have purchased a megasquirt for about the price I paid for the carb intake, but I didn't because of the horror stories I heard about the opti-spark distributor.

The main problem I have with the carb intake is that the truck runs the best when the outside temp is in the high 80's or higher. It's like the intake doesn't get hot enough and the fuel doesn't vaporize.

My LT1 is out of a B body also (Police car). I have a stick shift, and if I had an automatic with around 1600-1800 rpm stall it probably wouldn't be a big deal. With the stick I tend to drive around town at 1200-1500 RPM and it doesn't want to pull smoothly at that RPM unless you really ease into the throttle.

I've had 3 different carbs on the truck and they all had problems. Quadrajet would bog when opening the throttle in neutral, and a vacuum secondary Holley 750 and also a 650 double pumper. The double pumper has annular discharge boosters and is fully adjustable with air bleeds (and I've made tons of changes to try and get it right).

The carb intake pull very hard once I get past about 1800 rpms. The B body cam falls off probably around 4000 RPMs but the engine will easily rev to around 6000 doing a burnout (yes, it's a dually!).

Oh yeah, and the LT1 can be a bit picky about gas. Even with 93 octane I have to watch out for detonation. But my vehicle weighs 5500 pounds. It also seems to like a good amount of advance. I probably need to get my advance curve in sooner (I have a stock accel HEI replacment).

I had to notch the truck's frame to clear the A/C delete pully also. I bought the A/C delete pulley and the pulley was huge. I went back to autozone and then bought a smaller pulley (they sell just plain pulley's and they let me look through the boxes until I found one that would work) and mounted it onto the A/C delete bracket I bought. Then I cut the stock belt and guestimated how long a new belt needed to be with the smaller pulley and bought that from autozone. It works perfectly.

It definitely has good power. Not like a big block but decent.


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