throttle body spacer?

[bungea]

Im wondering what improvement the throttle body spacer does? Would it be a smart thing to get if you lived in a state with cold weather?

I'm driving a 97 grand prix gt vin k 4dr sedan. 137000 miles.

Any recommendations on cheap mods to improve horsepower. Already installed a k & n air filter into stock filter box.

[GregGP]

From what i hear, they are worthless.. You could do it if you want though. I hear that they are great if you're planning on installing nitrous.

[BNaylor]

Nothing to be gained on a basically stock NA SI 3800 engine. The supercharged L67 SII 3800 engine is a different story. The spacer helps reduce knock retard (KR) due to the heat generated by the supercharger and passed on to the throttle body.

[tblake]

If you live in a cold state forget it. The spacer blocks coolant flow through your throttle body which could ice up as you are driving. Not worth an accident. Even on the supercharged 3800 motors, I don't think the performance gains are anything to write home about.

[jeep2002]

the spacer does work depending on the setup and driving style. I have one on my jeep grand cherokee and gainded about 2 mpg. I dont know where the coolant being blocked comment is coming from because thats not the case on the jeep. yes i do own a grand prix. I have to find it, but there is a webpage that says do not use a spacer on a sc engine, even though they sell them.

[BNaylor]

Originally Posted by jeep2002

I have to find it, but there is a webpage that says do not use a spacer on a sc engine, even though they sell them.

I'd like to see that because I disagree with that. I've used one for well over 8 years on my GTP.

The spacer if used on a NA or SC SII/III 3800 engine will block coolant going to the throttle body. You may or may not get driveability or emissions issues depending on where you live. Climate, weather, etc.

[Stealthee]

Spacers do nothing.

The theory behind throttle body spacers was trying to get the air to swirl going into the lower intake. Old school carbed vehicles had success with spacers because the carb was the upper intake and the air got a swirl going into the lower intake with fuel mixed in.

On a TB vehicle it canNOT work. It has to pass thru the upper intake and all the runners first, then proceed into the lower intake. The "swirl" is gone by the time it get fuel injected into it.

The things are bunk and junk.

[rickisrad]

Originally Posted by Stealthee

Spacers do nothing.

The theory behind throttle body spacers was trying to get the air to swirl going into the lower intake. Old school carbed vehicles had success with spacers because the carb was the upper intake and the air got a swirl going into the lower intake with fuel mixed in.

On a TB vehicle it canNOT work. It has to pass thru the upper intake and all the runners first, then proceed into the lower intake. The "swirl" is gone by the time it get fuel injected into it.

The things are bunk and junk.

Not sure what you are talking about....swirling???? On the supercharged grand prixs the spacer provides additional protection from knock retard. It helps keep the throttlebody cooler by blocking the coolant passage and moving it away from the supercharger , which gets extremely hot.

hey BOB or Tim, have you guys heard of any cases of the throttle body freezing up from the spacer? I live outside of cleveland, I have the spacer but I have not put it on yet. I have not heard of this issue.

[Stealthee]

That theory doesn't work. The air is heated when its compressed by the supercharger much more than the coolant would ever make it.

[rickisrad]

here read this

http://www.zzperformance.com/downloa...acer_Study.pdf

[Stealthee]

I don't have the attention span to read 6 pages. There is no way the spacer can help cool in the incoming air more than it will be heated by the supercharger. I know exactly what blocked coolant passages do and the answer is nada.

You want a cooler intake charge? Get a intercooler.

And cooling the TB itself isn't going to reduce knock because all it does is restrict the amount of air getting to the engine/supercharger. Keeping it cooler will not even reduce the incoming air temperature. It might keep it the same as when it came in thru the air filter for a millisecond, then it starts to be compressed by the supercharger. Compression of that air then creates heat.

There was a company in the 3000GT/Stealth world that offered a TB spacer on its website for a mere 10 hours. They took massive heat for even thinking about selling a product that has been proven bunk many times. After a huge beatdown on another forum, they promptly removed it.

[BNaylor]

Good post rick and good read. The data on page 5 was good enough for me. See below. My '97 GTP is too old for an intercooler and I'm satisfied with its performance as is.

BTW - Also, I run the ZZP 72mm ported throttle body and my Eaton M90 Gen 3 blower is S ported. The SC pulley is 3.0". IMO it doesn't hurt and everything helps. It is not just one mod but the totality considered together.

The throttle body’s temperature dropped an incredible 69°F!!! Not bad for an inexpensive easy to install bolt-on product.

The most impressive finding to me wasn’t the temperature of the throttle body but the temperature of the supercharger. The heat gains to the air through the throttle body must have been significant prior to adding the spacer. We dropped the supercharger body temperature by approximately 29 degrees Fahrenheit! This should greatly reduce knock in our quest for high performance, and allow us to put more power to the wheels on those hot summer days at the drag strip.

[BNaylor]

Originally Posted by rickisrad

hey BOB or Tim, have you guys heard of any cases of the throttle body freezing up from the spacer?

Nope. Not to my knowledge. If anything will cause the TB butterfly to stick it won't be the cold weather and lack of cooling bypass into the throttle body. Just good ole carbon as usual and lack of maintenance.

This is all I could find on freezing but just anecdotal info.

Click here

Throttles in Cold Weather

Some throttle bodies are equipped with lines for coolant bypass. These were put into place by manufacturers like Dodge in case there was a danger of throttles freezing in cold weather. There have not actually been any reports of throttle bodies freezing in cold weather, and nearly all throttle bodies have been tested in sub-freezing conditions to make sure they still operate without flaws.

BTW - Funny how he mentions Dodge 'cause obviously GM does it too.

[Moppie]

Throttle bodies and inlet manifolds are heated in order warm the intake air which is done for two reasons:

1, Warm air supports smaller fuel droplets, which helps produce a better burn in the combustion chamber.

2, Prevents ice building up in very cold climates.




The effects of throttle body spacers vary greatly by engine, type of spacer and what the intentions are.

Some are advertised as a way of increasing intake length, and therefore increasing torque.
This is total BS. While intake length does effect power and torque delivery, you need to do more than just fit a spacer.

Some are advertised as being able to make everything better by altering the airflow through the intake.
Again, these are total BS.


Then you get more engine specific spacers that may do things like allow you to run a different size throttle body, or alter the affect of coolant flow through the throttle body and inlet manifold etc. Some of these work, some don't.


However, as a general rule, throttle body spacers of any kind are junk and best avoided.
The exceptions will have some sound reasoning and well reviews tests to support them.

[BNaylor]

Originally Posted by Moppie

Some are advertised as a way of increasing intake length, and therefore increasing torque.
This is total BS. While intake length does effect power and torque delivery, you need to do more than just fit a spacer.

Some are advertised as being able to make everything better by altering the airflow through the intake.
Again, these are total BS.

I haven't seen any advertisements specifically related to any L67 SII 3800 or L32 SIII 3800 engines as to what you are saying above. Many of us with modded L67 or L32 engines use the TB spacer from ZZP which has been available and advertised for several years. This is their claim (see link below) and all it mentions is to help isolate the supercharger from the throttle body among one of the reasons.

Click here

Also, this spacer allows you to adapt a ported 72mm throttle body versus having to grind on the supercharger inlet. I use the Stage 1 Ported 72mm Throttle Body from ZZP.

A throttle body spacer will insulate your TB from the heat of the supercharger. Keeping your TB cool will help keep your intake temperatures down thus reducing KR and increasing HP potential. The inlet is 72mm to work great with our ported throttlebodies.

Originally Posted by Moppie

The exceptions will have some sound reasoning and well reviews tests to support them.

Good point! I'll stick with the exception.