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Throttle-Body Upgrades

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Trent Riddle | Writer
Posted November 1, 2001

Improve the Power of Your ’87-’95 EFI Chevy

Step By Step

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  • The Turbo City Hi-Flow throttle body (left) has larger throttle bores, shaved throttle shafts, radiused air inlets, and rounded throttle-plate screws. This unit is said to offer a 10-20 percent increase in airflow over the stock unit’s capacity.

  • The stock fuel-pressure regulator found on the bottom of the injector plate is replaced with an adjustable unit. This allows for the fuel pressure to be adjusted over a range of 9 to 13 psi. By increasing fuel pressure you can enrich the fuel mixture to match the increased airflow of the new throttle body.

  • An injector spacer is used between the injector plate and the throttle body. This spacer is said to increase airflow by 5-6 percent and to provide a wider injector spray pattern for better fuel atomization.

  • Once the throttle-body has been assembled using a combination of new and original parts, it can be installed on the motor. First, install the throttle-body spacer from the kit with a gasket on each side, then bolt on your upgraded throttle-body.

  • The final part in the kit is Turbo City’s Air Flow Enhancer. This unit is riveted to your air cleaner base and replaces the stock air-cleaner spacer. The tapered style is said to improve airflow to the throttle-body by 6-10 percent.

  • Here is the new Hi-Flow throttle-body in place on our engine. It looks stock, but that’s just an illusion. We even opted for a new pair of matched injectors, as one of ours was leaking. Although not part of the Powerpackage, this is a great option to consider.

Everyone can use more horsepower. One example of a simple upgrade that provides more horsepower is the Powerpackage kit from Turbo City for ’87-’95 GM throttle-body fuel-injected GM engines.


Brea Auto Electric
Brea, CA 92821
Turbo City
Orange, CA