Newtdog73

I am getting ready for a Carbon clean and was curious if anyone has experience with manifold spacers?

Since there is no labor involved because I am already getting the carbon clean...I thought I would put them on.

gibsonl

I did it and I love it. It's more tq than you'll pick up from the cc alone. Also helps the motor run cooler and stronger for longer.

Newtdog73

Thanks! I will add that to my list. I should be getting my carbon clean in 2 weeks.

Reggie

Do you have a link to one?

Newtdog73

Reggie,

Here is the one I am looking at.


http://jhmotorsports.com/shop/catalo...31fbcf98f11c77

Reggie

Thanks. I have to think about this. As a engineer there are a couple of things that bother me.

1. The heat will eventually get through from the engine to the manifold. The thermal break is not enough to prevent the heat from moving to the manifold over time.
2. The air is moving fast and does it really heat up in the short time in the manifold?
3. The engineers designed a specific flow length - does this affect that?
4. If this is significant - why did Audi not do it?

gibsonl

I'm not engineering minded so you'd probably have to ask JHM those things. I'm not sure if I would consider the approximate 5-10wtq "significant," but the 5-10 degrees cooler running temp seems to help out for track use.

sakimano

I thought they should add zero torque or power. They're simply there to limit heat transfer to the intake manifold.

1. maybe. I don't think JHM says heat will never make it...they're simply putting something that's not conductive in between the block and the manifold. Their goal is to slow down heat soak from this one event...not to prevent heat ever making it to the manifold.

2. ever see how intercoolers work? heat exchange is a pretty incredible thing...in an instant it happens.

3. dunno. Good question. JHM (and VAST before them, and just about every domestic platform's tuning companies) tested this and had positive results. In the B6/7 S4 and RS4 world, all of the fastest cars use these spacers. That's maybe a co-incidence. It's also maybe an important factor. They don't make you faster...they just slow down how long heat soak in this one area will make you slower.

4. Are you assuming Audi did everything they could for the B7 Rs4? Your question infers that if it was good for power/performance, Audi would have already done it. Let's test that theory. Being an engineer, you should look at the whole car and ask yourself if your 'if Audi didn't do it, it must not help' theory holds water. I don't think it does.

Why did Audi put a 2.35" neckdown at the end of the downpipes? We know that kills flow, and holds the car back. We know a 2.75" full back with no restrictions is far better for performance. So...why did Audi not use a 2.75" exhaust with no jagged bends?

Why did Audi not use a crossover in the catback when on an NA car, we KNOW that it helps exhaust scavenging and adds efficiency and power?

Why did Audi not use straight through mufflers with a perforated core, rather than a highly baffled flow reducing design when we know this helps power on an NA car?

Why did Audi not give the car 15-20 more whp from the tune when we know it's easily unlocked?

Why did Audi write a torque limiter into the tune via artificial throttle body restriction held back to 52% from 0-5250 RPM? Heck, why did Audi not add a supercharger? We know that adds power.

Audi is not interested in giving us the full monty. They knew they had to relaunch a very similar engine on two more platforms (B8 RS4 and RS5) and needed to leave some on the table. They always do. They also have cost, emissions, sound etc. to think about.

BADRS4

As much as it pains me to agree with the Japanese vodka, it's true. Audi definitely didn't give us all the Performance advantages on their cars especially the US version of the RS4. Even the European version has the thicker steering wheel, more aggressive tune, lower ride height, less pre-cat's for emissions, racing seats etc. We really have to spend about $10k just to get the car up to European standards of performance. They also seemed to have created a solution for carbon build up on the RS5 (similar to what I believe JHM is finalizing) So as technology advances, so do our cars. IMO, this is why so many of the newer cars are going Turbo vs. NA V8. (the new M3, the new M5, S4, S5) you can get an increase of 60-80hp and huge gains in torque in one software tune simply by turning up the boost on the turbo). I have also heard that many Auto manufacturers release their new models to top tuners before they even hit the street..so by the time the car is released to the public, many of the tunes are already available. The Auto manufacturer has recognized the "mod" community and they can release cheaper "tamed" cars with higher fuel efficiency for the conservative market, and know that those who are enthusiasts will tune their cars to their desire.

Newtdog73

@Sakimano......Why did Audi not give the car 15-20 more whp from the tune when we know it's easily unlocked?

Can you explain this?