EGR spacer question

1992blkGT said:

I'm going to order a 75mm throttle body soon, and I'm trying to decide if I need to get the throttle body with EGR spacer or not. I removed the smog pump and the tube that normally routes to the smog pump is just sitting in my engine bay. Will the car run fine if I get a TB without an EGR spacer? The non-EGR TB is a lot cheaper that is the only reason I am asking. If I need to do more to allow a TB w/o EGR, what all is necessary? Thanks for the help!

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Michael Yount said:

For others reading the thread - another thing that often happens when the egr spacer is deleted (moving the throttle body much closer to the intake) is that the bracket that holds the throttle cable usually interferes with the valve cover requiring a modified bracket or a upper/lower spacer to create more clearance.

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91BlckGT said:

The EGR spacer does something different than the smog pump.

The smog pump adds oxygen to either the cats, or the cylinders heads, to help create a cleaner combustion. With modern cats, its' not needed anymore, and most people can pass emissions w/o it.

The EGR spacer is used to circulate coolant around itself, to help cool the throttlebody / upper intake.

This is because there are exhaust cross-over ports milled into the stock heads and most street-intakes. These ports (found in the middle of the heads between the cylinders, and generally on the bottom of the intake, route exhuast gas BACK into the throttle body (via the EGR valve) and back into the intake. This further reduces emissions.

If you have blocked the coolant lines to your spacer, then there is no point in having it, other than to help line up the inlet tube from the MAF to the TB. Ideally, if you've removed the coolant lines, then you're either running race heads, or have blocked that cross-over port.

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