Throttle / Mainfold spacers, do they work? - PeachParts Mercedes-Benz Forum

JayRash · #1 10-21-2012, 08:43 AM

well do throttle / manifold spacers work? if yes how?
i can see how a tb spacer might work as it can slightly increase the total volume of the manifold without altering the runner length.

but a manifold spacer will increase runner length and i always thought that should harm top end. whats ur take on that?

engine is the M104 3.6

oldsinner111 · #2 10-21-2012, 08:49 AM

from what I've read its hype.If you have a m104 with the idle butterfly valve it ain't going to do anything.it might help a v8 but the racers and builders who I talk with don't use them.Ain't talked with you in awhile.I will be adding electronics to my nitrous setup.

Chlippo · #3 10-21-2012, 01:55 PM

I haven't tried it myself, but i have conisdered the option so did some reading and ended up with: It does not work. But hey, thats me and my readings, thats all

MAG58 · #4 10-21-2012, 03:08 PM

Technically the idea behind it, increasing plenum volume, does lead to more power. However, a simple 1/2-1" thick spacer doesn't really add enough to the plenum volume to do any significant difference. You need to be adding 10%+ to the volume of the plenum before you start seeing a difference.

Dearlove · #5 10-22-2012, 12:41 AM

what happened to ITB's.... lol

duxthe1 · #6 10-22-2012, 01:23 AM

I've got a t/b spacer, and it works!!!! It gives me about 1/2" clearance on the TPS sensor

DieselPaul · #7 10-22-2012, 08:29 AM

I thought long runners would move your powerband higher. However since your injectors aren't moving like they would in a TBI or a carb setup you're probably having less effect on the power band you're just stacking more air in the intake which could still change some velocities and move the powerband just not as drastically as high rise manifold on a small block Chevrolet.

I had an EFI car where I was able to make runner spacers and a throttle body spacer, each 1/2" (I was in high school and had time not money lol) and saw no noticeable gains but that was not a Mercedes. Someone in that same community machined his runners down by a half inch and he saw a torque gain on a dyno. However it was marginal.

If you can make one cheap and easily may be worth a try but if 1/2" aluminum makes a gigantic difference, AMG probably would have cast the intake 1/2" longer.

JayRash · #8 10-25-2012, 01:08 PM

The Nissan and infinity guys with the v6/3.5 engine swear by the spacers. Personally I can't see it giving and measurable gain.

DieselPaul · #9 10-26-2012, 05:12 PM

The VQ35 guys do make actual WHP off of those plenum spacers but if you look at the design of the intake manifold on a VQ the plenum is pretty big so you're adding a larger volume of air than just a throttle body spacer.

If you have access to a dyno for cheap try it and get back to us it would be really cool if it adds power on an M104, spacers are cheap to make.

MAG58 · #10 10-27-2012, 02:29 AM

Quote:

Originally Posted by DieselPaul

The VQ35 guys do make actual WHP off of those plenum spacers but if you look at the design of the intake manifold on a VQ the plenum is pretty big so you're adding a larger volume of air than just a throttle body spacer.

If you have access to a dyno for cheap try it and get back to us it would be really cool if it adds power on an M104, spacers are cheap to make.

The other thing is that most of those spacers act as a thermal insulator. The top of the VQ manifolds can radiate a ton of heat into the air charge otherwise.

FWIW, My TB adapter adds about 3/4" of a spacer to put the BMW TB on, and if it produces any meaningful gain over the factory, I cant tell. It may be helping, but there needs to be a significantly larger increase in volume over that which I'm using.

MagnumPI · #11 10-27-2012, 02:25 PM

Tried a carburetor spacer on an old 350 Chevrolet engine, but it was like 4 inches. There was some measured gain, about what you'd expect, a few HP.
It was along these lines:
Aluminum Open Carburetor Spacer, 4 Inch - Speedway Motors, America's Oldest Speed Shop

DieselPaul · #12 10-27-2012, 06:04 PM

That's like the poor mans tunnel ram haha.

However with a carb you're also movin the fuel itself further up which will have more effect than just spacing the throttle body than on a EFI car

97 SL320 · #13 10-28-2012, 10:05 AM

On a V8 carbed intake, a spacer helps because the air / fuel below the carb has longer to settle and reattach before it makes the 90* turn on it's way to each cylinder.

On a FI engine that has only air to deal with, a 1/2" spacer won't do anything unless there is a restriction just after the throttle body in stock form. In other words , a FI spacer is one of those costs near nothing to make , has a decent profit margin and is a feel good mod that someone will buy.

whatever · #14 11-10-2012, 09:43 PM

Imho it's worthless.

TB spacer won't do anything, because you don't have fuel going through the TB, so you have nothing to save from heat (they act as insulator pretty much on carbs).

Manifold spacer, i.e. between manifold and head would work, but that would increase torque on low RPM, and yes, you lose high RPM.

As Hans-Werner Aufrecht said:
"You can't really improve a Mercedes, but you can make it different".

Kinda! Though I have something to improve, but it's all in words and drawings now, we'll see if it has a gain some what later.