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Should I have a spacer under my 750 carb on a high rize

Customer Question
Should I have a...

Should I have a spacer under my 750 carb on a high rize intake

Mechanic's Assistant: What year is your 750?

About 78

Mechanic's Assistant: Are you fixing your 750 yourself? What have you tried so far?

I put the motor in my 56 chev truck and I have a hesitation in the acceleration

Mechanic's Assistant: How old is the transmission? Have you checked the fuel filters?

700r4 out of a87 and new filters at the carb

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

Everything is new,carb dist, wires, plugs

Submitted: 1 year ago.Category: GMC
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Answered in 11 minutes by:
3/29/2017
GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago
Jared D
Jared D, ASE Certified Technician
Category: GMC
Satisfied Customers: 2,314
Experience: Shop Supervisor at County Fleet
Verified

Hi,

Which engine do you have in this truck?

A hesitation when you first hit the gas pedal usually means a weak or poorly adjusted accelerator pump. However, if you have a high rise on an engine that doesn't make much torque in the low RPM range it's going to hesitate. A high rise will only make power after about 2500-3000 RPM. Normally when running a high rise you normally need to run at least a 2500 stall torque converter so the engine revs up a little higher before it engages the transmission.

Do you know the stall speed of your converter?

What model is the carb?

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Customer reply replied 1 year ago
standard tc, 750 edelbrock
GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago

Which engine?

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Customer reply replied 1 year ago
no too expensive
GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago

I'm sorry? Did a phone call thing pop up? That's not me- it's automated.

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GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago

Phone call isn't necessary. Just need to know the engine size.

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Customer reply replied 1 year ago
383 stroker
GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago

750 is probably ok for a 383 stroker. Typically you don't want to go over a 650 or so with a small block, but a 383 is a fairly large small block.

When you say hesitation does it eventually start to pull hard or is it pretty sluggish all the way up?

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GMC Mechanic: Jared D, ASE Certified Technician replied 1 year ago

Please don't forget to rate- that's how just answer compensates me for my time.

Let me know if you need additional info.

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