What does everyone think of getting a bigger throttle body and throttle body spacer on a stock bullitt? Is it true the spacer will give better fuel economy? Just wondering if anyone as added these mods.
Steeda sells a TB spacer on their site that claims to add Hp and better fuel economy.
I have never had to retune a car when adding a TB. When I upgraded my SVT Focus to a 67mm TB it did only add 3 hp peak but i did get an extra 7-10 miles per tank and had a better throttle response with no tune. I was just wondering if the Mustang has the same effects.
Somebody please enlighten me as to exactly HOW increasing the plenum-volume by adding a spacer after the throttle-body on a DRY INTAKE MANIFOLD is supposed to increase HP and MPG? As there is a tuned-length to each runner, and the plenum itself is tuned, I can see MOVING the power around the rpm-range a bit (but not much!), but no increases due to just a simple 1" deep by whatever dimensions of opening the spacer happens to be.
This works a bit-better on a carbureted engine - but even a single-plane carb'd intake has comparatively small plenum-volume compared to most any modern dry-type EFI intake. Mostly, it also just mostly moves the powerband up the rpm-range too, and "adds" little to no power (with a major caveat being phenolic spacers that actually help to keep the carb and the fuel contained in the float bowl "cooler").
And, putting one on a carb'd engine DOESN'T automagically work wonders - I've seen engines actually LOSE a bit of power and driveability by doing this, so we pulled the spacer back off and tossed it in the corner...........
Spacer=No!Larger throttle body,is it really worth a few hundred bucks for a claimed few HP.Put the money in the tank or feed the pig.Only justification for a larger throttle body is an increasee in demand for air.So..............
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