Tumble flaps

[RS4_Ollie]

Hi, Im going to do a carbon clean soon and was reading a lot of people remove the tumble flap.

What are the pros and cons of doing so?

[coffey555]

Better airflow but slight loss of torque at lower rpm I believe.

I left my ones in after my carbon clean as there was no play in them.

Wiki says the tumble flaps are there to assist low engine speed combustion.

[RossDagley]

It runs a little more lumpy on part throttle openings, especially when cold. But the benefits are less restriction and less to gum up/go wrong!

[adsgreen]

The tumble flaps simple close off half of the intake path leading to the cylinder. As it's low rpm this isn't a restriction but does have the effect of increasing the velocity of the air into the chamber so when the fuel is injected it can mix up a bit better.
If properly mapped there is no loss in power but will hit economy by a couple mpg when just pootling about

[RS4POWER]

In order for you to remove the tumble flaps you will have to punch out the freeze plugs. There is a company out there that recommends reusing them by applying loctite upon reinstall but I strongly suggest you don't. New freeze plugs can be sourced (not by Audi) but you'll have to dig a little bit. PM me if you need them.

I have been running a deflapped p/p IM for years now with no adverse effects. Highest g/s I saw was 174 per bank. I believe with a tune that removes the tq limiter and considers less manifold restriction, p/p would tie in nicely. Perhaps Doug from MRC can chime in on this.

If anyone here is looking for a port/polished, deflapped IM (work performed by silverrs4) PM me, I have a spare one for sale.

[skydude]

I used a very small ratcheting wrench with a very short torx bit to remove flaps without touching the freeze plugs. Had them all out in 30 minutes

[RS4_Ollie]

If they aid low down torque I think I'll leave them in as it's a little lacking in the low torque dept.

[RS4POWER]

I used a very small ratcheting wrench with a very short torx bit to remove flaps without touching the freeze plugs. Had them all out in 30 minutes

This is good to know.

[bam_bam]

Haha, flaps...

[hlbeckley]

Better airflow but slight loss of torque at lower rpm I believe.

I left my ones in after my carbon clean as there was no play in them.

Wiki says the tumble flaps are there to assist low engine speed combustion.

Hmmm I have a different view, I had low end torque pick up, albeit ever so slight

It is a bit lumpy below 3k revs when cold
The power gains post de flap and carbon clean are really very noticeable

No error codes yet either, I vote do it and add I take spacers too at same time

[PetrolDave]

The power gains post de flap and carbon clean are really very noticeable

Was the power gain due to de-flapping, carbon cleaning or both?

If you did them both at the same time then it's impossible to tell, but anecdotally carbon clean is worth c. 30bhp.

[hlbeckley]

Both same time but driven a de flapped post CC and flaps in, delivery is very different