A3 1.8T Turbo Intake Pipe Questions

[portsA318T]

Hi Guys,
Anyone here done this MOD? I'm looking at the Forge full intake pipe replacment or the Neuspeed metal version. Any recommendations and any noticable improvments to the engine; gains/sound etc etc.
Thanks

 

[james0808]

I put one on my golf and didn't notice any difference,it was the forge one.

 

[tommo-turbo]

I put a Forge one on my S3 and it was one of the best mods I've done. It makes the most of a remapped car.

 

[Timbo]

I put a Forge one on my S3 and it was one of the best mods I've done. It makes the most of a remapped car.

I believe the A3 1.8T has a metal TIP, so doesn't suffer from TIP collapse as the S3 does.

 

[Booth_S4]

so can you get a metal version or not?

 

[james0808]

You can get a neuspeed metal one but most people go for the forge silicone one as it replaces the whole TIP.

 

[Ess_Three]

I fitted a forge TIP to my chipped S3 and go no gains - dyno proven.

I guess I was just refusing the placebo effect to convince me that my wallet being lightened was equal to a rise in performance....

 

[pablo]

what about the collapsing hose vid we have all seen?

 

[james0808]

Isn't that only on high boosting S3's?Not all obvisously.

 

[portsA318T]

Reading up on the websites, it says that replacing the standard pipe can increase air flow by upto 70%. Doesn't this in anyway help the spool time and perhaps reduce lag. Also does the A3 need to be mapped to make use of this or would it be ying without the yang if i haven't got it mapped.

 

[loftgroover]

Reading up on the websites, it says that replacing the standard pipe can increase air flow by upto 70%. Doesn't this in anyway help the spool time and perhaps reduce lag. Also does the A3 need to be mapped to make use of this or would it be ying without the yang if i haven't got it mapped.

The TIP will not aid spool time or have any effect on lag. There is not much vacume at this point so i think the gains will be extremely marginal if any at all, as Ess has indicated.

Unless the original pipe is really knackered, i think money is better spent elsewhere...

 

[dultanur]

i think you should try and see... after a remap if your car looses a ton of power around 5000rpm, your tip may be collapsing. if not, why bother?

 

[Ess_Three]

what about the collapsing hose vid we have all seen?

I fitted the little sleeve thing sold by AmD...as a preventative measure, when I was running the standard inlet hose.
Although I never suffered from the collapsing hose, I thiught it best to take steps to make sure it didn't happen.

As for high boost...mine was running 1.89 bar peak and 1.3 bar sustained.
I'd say that was high boost for an S3.

The Forge TIP added nothing...not that it's a slur of Forge...it looked good, but in reality added nothing. Nothing dyno provable anyway.

 

[Timbo]

Reading up on the websites, it says that replacing the standard pipe can increase air flow by upto 70%. Doesn't this in anyway help the spool time and perhaps reduce lag. Also does the A3 need to be mapped to make use of this or would it be ying without the yang if i haven't got it mapped.

You definitely won't see any difference if it's not remapped. Standard 1.8T's aren't at all laggy anyway.

what about the collapsing hose vid we have all seen?

That's an S3. The original question was about a 1.8T (I presume?). Given the 1.8T has a metal TIP as standard it can't collapse.

 

[Tallpaul]

I've got one and the only thing i know for a fact was it made my dump valve wooshier

But on the subject of pre-compressor restriction, a wise man once told me this:

You need to look at the wastegate duty required to meet the boost target.

A more restrictive intake (pre compressor) will result in a lower pressure at the compressor intake. The post compressor pressure will be the same regardless (i.e. that set by the ecu mapping). To make this post compressor pressure the wastegate soleniod will be driven to a duty cycle (i.e. controlling the amount of exhaust gas that bypasses the turbine). The pressure ratio across the compressor will increase as the pre-compressor pressure falls, hence the compressor will be required to do more work, which does 2 things

1) heats up the charge air more - so for the same IC efficiency the plenum air temp will be higher
2) requires more work from the turbine

to meet this greater demand for turbo shaft power the wastegate will be closed more, allowing less exhaust gas to bypass the turbine via the wastegate, and increasing pre turbine pressure. This increase in pre-turbine pressure also has 2 effects:

1) means the piston must work harder to expel the burn gasses into the exhaust manifold on the exhaust stroke, which reduces crankshaft torque

2) reduces the pressure ratio across the engine (plenum pressure is the same as before, exhaust manifold pressure is higher) so actual airflow through the engine will reduce, limiting torque

This is further complicated by the ME engine management actually requesting a target air mass flow, not a plenum pressure, so it will actually have to increase plenum pressure to restore the target airflow, which also causes all the above effects.

This is why the more boost you run the harder and harder it is to make more power, i.e. the 1st 5psi boost increase gets you 20bhp, the next 5psi only 10bhp etc.

Pre compressor pressure losses are a real problem on high boost turbo engines, and most turbo's will loose approx 1.5 - 2 bhp per kPa increase in pre-compressor pressure loss.

 

[Timbo]

Pre compressor pressure losses are a real problem on high boost turbo engines, and most turbo's will loose approx 1.5 - 2 bhp per kPa increase in pre-compressor pressure loss.

So should we read that as "not really worth it for K03/K03s equipped engines"?

Very informative post BTW as per usual Paul.

 

[Tallpaul]

So should we read that as "not really worth it for K03/K03s equipped engines"?

Here's the Forge TIP next to the OE K03 TIP:

I couldn't 'measure' any performance increase through fitting it but looking at it i just think 'it must do something'. Up to you really, i was going silicone for all my hoses so bought it anyway.

 

[loftgroover]

I've got one and the only thing i know for a fact was it made my dump valve wooshier

But on the subject of pre-compressor restriction, a wise man once told me this:

You need to look at the wastegate duty required to meet the boost target.

A more restrictive intake (pre compressor) will result in a lower pressure at the compressor intake. The post compressor pressure will be the same regardless (i.e. that set by the ecu mapping). To make this post compressor pressure the wastegate soleniod will be driven to a duty cycle (i.e. controlling the amount of exhaust gas that bypasses the turbine). The pressure ratio across the compressor will increase as the pre-compressor pressure falls, hence the compressor will be required to do more work, which does 2 things

1) heats up the charge air more - so for the same IC efficiency the plenum air temp will be higher
2) requires more work from the turbine

to meet this greater demand for turbo shaft power the wastegate will be closed more, allowing less exhaust gas to bypass the turbine via the wastegate, and increasing pre turbine pressure. This increase in pre-turbine pressure also has 2 effects:

1) means the piston must work harder to expel the burn gasses into the exhaust manifold on the exhaust stroke, which reduces crankshaft torque

2) reduces the pressure ratio across the engine (plenum pressure is the same as before, exhaust manifold pressure is higher) so actual airflow through the engine will reduce, limiting torque

This is further complicated by the ME engine management actually requesting a target air mass flow, not a plenum pressure, so it will actually have to increase plenum pressure to restore the target airflow, which also causes all the above effects.

This is why the more boost you run the harder and harder it is to make more power, i.e. the 1st 5psi boost increase gets you 20bhp, the next 5psi only 10bhp etc.

Pre compressor pressure losses are a real problem on high boost turbo engines, and most turbo's will loose approx 1.5 - 2 bhp per kPa increase in pre-compressor pressure loss.

I think this needs to be put in perspective. Yes, increasing the pressure diffential accross the compressor makes the turbocharger/engine have to work harder to maintain the same compressor outlet pressure. However, this phenomonon only becomes a problem in 2 instances:

1. High altitude operation wher ethe ambient air is low pressure (ie >2500m is a massive problem for turbocharged cars. )
2. Seriously blocked air intake system (pre compressor)

So, unless your turbo inlet pipe is blocked or colapsed changing the inlet pipe will make NO difference to the performance of your engine.

 

[Tallpaul]

So, unless your turbo inlet pipe is blocked or colapsed changing the inlet pipe will make NO difference to the performance of your engine.

lol, i knew you'd love that post

I pretty much agree, for the K0X series of turbos. I'm sure the pressure differential WILL become more significant when generating the pressures associated with larger turbos. The guy that wrote that little summary prepares World Rally Cars.

 

[loftgroover]

lol, i knew you'd love that post
.

Bu**er. Am i really that obvious...?

I pretty much agree, for the K0X series of turbos. I'm sure the pressure differential WILL become more significant when generating the pressures associated with larger turbos. The guy that wrote that little summary prepares World Rally Cars.

Ahhh, he has to deal with another issue as well then, the WRC turbos all have restrictors built into the front of the turbo to limit engine power. Not good.

The altitude problem is a big issue for WRC events in Turkey and Cyprus and hill climbs like Pikes Peak. The big problem is that the turbo spins MUCH faster to produce the same boost and goes bang very quickly.

 

[dultanur]

you don't have to worry about the rally of turkey anymore, they removed it from the calender indefinately

 

[Timbo]

Paul - your stock TIP doesn't look like the one in the Neuspeed ad:

(apologies to Awesome-GTI - I stole the photo from your website).

Ahhh, he has to deal with another issue as well then, the WRC turbos all have restrictors built into the front of the turbo to limit engine power. Not good.

I read on wikipedia (that source of all truth ) that WRC cars don't have a BOV either.

http://en.wikipedia.org/wiki/Waste_gate#Wastegate_Chatter_Myth

 

[Tallpaul]

lol, well that's the TIP i removed from my Turbo? But who am i to argue with what Neuspeed say?!

Oh, and don't start Loftgroover on whether WRC's have BOV's... There's a thread around here somewhere about it...

 

[Timbo]

lol, well that's the TIP i removed from my Turbo? But who am i to argue with what Neuspeed say?!

Is the end part of your old one metal? It looks like plastic in your photo.

I have no idea what mine looks like - presumably the same as yours - I had assumed it was the same as the one in the Neuspeed pic.

 

[Tallpaul]

It's probably the TIP from a later engine code or even a K03s? My stock TIP is metal, just painted black.

 

[james0808]

Mine was the same as Tallpaul's on my golf.Is there any benefit to fitting larger diameter pipe after the turbo from turbo to intercooler or from intercooler to inlet?

 

[Tallpaul]

The only pipes i can say are 100% worth changing are:

-The one from the N75 to the charge pipe as these have several bends and everyone i've ever seen has had at least a small crack/split in.

- The one from the turbo outlet to the charge pipe. After a remap this pipe gets so hot it literally becomes squidgy and balloons, it then very easily pops off under full boost. This isn't a good look when hammering it down a dual carriageway as it goes pop and for a split second you think your turbo has blown up

All the others i've changed for completeness and to get the two i've mentioned above you need to buy a kit of 5. Plus all the 3/5mm bore vac hoses are crap IMO and worth swapping to more durable/less prone to splitting Silicone ones.

All in all things gets pretty hot under the bonnet of a 1.8T and silicone hoses are far more durable than the OE ones. Plus the OE ones gat in a very sorry state if your car is 8 years old like mine.

 

[fab_giglio]

Hi, can anyone send me the link on where to buy the TIP (forge) for Audi A3 8P, 1.8 T FSI 2007 please? I dont know which one is the right one....

 

[<tuffty/>]

Hi, can anyone send me the link on where to buy the TIP (forge) for Audi A3 8P, 1.8 T FSI 2007 please? I dont know which one is the right one....

Forge don't list any induction parts for this car...
http://www.forgemotorsport.co.uk/product-filter/audi,a3+1.8+tfsi

You would also be better off asking questions in the 8P section dude... this is the 8L section

<tuffty/>