S3 Forge Twintake Review

KRL

KRL

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Here it is:
P2120388small.jpg


I will post up some more pics tomorrow hopefully once the weather gets better.


Why?
The OEM intake is limited in both design and materials due to the cost prohibitive nature of making mass produced intakes that can be used for multiple platforms and engine layouts.

The OEM intake has to meet a predetermined set of requirements for the 2.0T FSI and I do not believe that efficiency and performance are necessarily at the top of that list. VAG need to consider whether or not they can use the same intake for other models with relatively minor changes to allow for mass production and cost savings. VAG are also concerned with sound volume, maintenance and appearance.

The OEM intake contains several baffles and other unnecessary obstructions to the airflow to deaden the intake sound. This helps sell new cars based on how quiet the cabin sound is but doesn't help enthusiasts like ourselves who like to hear the sounds of the turbo and have the most efficient intake possible. A tubular style intake pipe will therefore get rid of these restrictions and allow you to hear sounds of the engine and turbo working.

The OEM paper air filter is a point of restriction. Performance filters maintain or exceed the OEM's filtration ability with alot more airflow potential. Filters with good filtration but high flow are just too expensive in comparison to the OEM paper filter and are therefore not used.

There are some good features of the OEM intake which would be nice to maintain:
- It is getting air from the highest pressure zone (high pressure = high air flow) on the outside of the car, the edge of the bonnet where it meets the grill.
- It is a sealed system meaning hot engine bay air should not enter it.
- Diameter of the MAF housing as this is what the ECU is calibrated to use
- Being built into the Engine cover it helps protect the engine bay from the elements

Bearing all of the above in mind in mind I will now list the features of the Forge Twintake:
- Tubular style intake with no baffles or obstructions
- It contains two performance dry filters
- It takes air from the OEM position at the top of the grill and from the top of the grill above the passenger headlight
- It is a sealed system
- The piping has an OD of 70mm which means the ID should be so close as to not matter to 67mm so the ECUs MAF scaling should work correctly

In conclusion I believe the Forge Twintake contains all the desirable features of the OEM intake while overcoming the negatives of the OEM intake. For me the only item which is missing would be the inclusion of an engine cover and I intend to cut my orignal engine cover to fit with the Twintake.
Why two filters are better than one?
This has already been explained excellently by Robin in his Twintake review:
Having twin filters is not a new idea on cars but Forge decided in early 2009 to investigate its potential for the 2.0T FSI engine (and now TSI version). As a relatively small English company with an established good reputation they would not have released it without spending an appropriate amount of time ensuring it worked flawlessly.

The main idea, though, is to create sealed inlets that allow for the introduction of the coolest ambient air possible. There are numerous debates among 'internet experts' but if the turbo system heats the air by say 50-70C before it hits the intercooler and the intercooler takes that back down by say 30-40C, then every degree colder your intake air then the lower your intake air temperatures are going to be post intercooler.

Cold air intake temp + Turbo increase temp - Intercooler reduction in temp = IA Temp in the manifold.

Apart from having the largest total possible surface area to the filtering media there are other benefits to a twin filter setup: Consider that a given filter size will present a given level of restriction to airflow, based primarily on the density of the filtering media. This will result in a given level of vacuum after the filter. Two identical filters, of the same level of restriction, applied to the same application as in this case, will apparently double the effective airflow possible by decreasing the restriction by roughly half. This will equate to more power potential.

The incorporation of a second filter doesn't introduce more airflow volume. The 70mm piping, which Forge say is the max allowable for proper MAF calibration, will only flow a finite volume of air regardless of the number of filters used. Higher flowing air filters, however, provide for a reduction in effort required to draw air through them due to a decrease in flow restriction. A larger surface area through which airflow is introduced, provides for the least possible restriction in flow.
Click to expand...
Sourcing
TBC for the S3. My car was used to develop a prototype which should lead to the full production version. I would imagine that it will be available from all the usual outlets, this link contains Forge's distributers:
http://www.forgemotorsport.co.uk/content.asp?inc=distributors

Products can be purchased directly from Forge as well

Fitting
Quite possible to fit as a DIY. For the more experienced DIYers fitting should take about 1 hour or 2-3 hours for the less experienced. I would not expect to pay more than 1 hours labour for the fitting if having it done by a garage.

I'm really impressed with the looks and quality of the Twintake. The fit and finish is superb, each time I open the bonnet it puts a big smile on my face seeing the intake and f[FONT=arial, sans-serif]or me the visual impact of the Twintake definitely has a wow factor! The Twintake mounts to existing points in the engine bay keeping things looking nice and tidy as well as being really solid.

[FONT=arial, sans-serif]Forge are taking the time to tailor the Twintake to the various VAG platforms rather than a "one solution fits all" intake. It must be a significant extra cost however I am sure it will show its benefits in quality and performance.

Other Intakes
There are many options out there:
- Carbonio
- ITG Maxogen
- EVOMS
- VF Engineering
- BSH True Seal
- Neuspeed P Flow
- Dblias
- ...

Performance
As part of the testing The Twintake was compared to the OEM intake on a dyno. Here are the results:
forge_twintake_dyno.jpg


Compared to OEM the Twintake made an extra 26 BHP up from 298 to 323.9 and 12lb/ft Torque from 285lb/ft at 3500rpm to 297lb/ft at 4320rpm. These runs were completed back to back within an hour of each other on the same rolling road. My S3 has no other performance mods apart from a REVO Stage 1 remap. At further levels of tune ( Stage 2 and Stage 2+) I would imagine that the performance gains would be even more compared to the OEM intake. The torque is giving nice gains across the entire rev range with more ‘area under the graph’ - the more area, the better the car will drive. Power does not look to be dropping off at the redline either, the car just wants to keep going! The turbo is spooling earlier with the Twintake - notice the power/torque lines are shifted up and to the left.

My car is suffering from a slight flat spot at 4400 rpm in both runs so please ignore this. It is something I will need to chase up and sort out seperately.

Driving around you can feel the performance gains. Throttle response has improved and it is at the top end where I feel the gains most. I've driven around 1000 miles with the Twintake installed now and the Long Term Fuel Trim is sitting at 4.7% indicating the MAF scaling is working nicely.

The sealed air inlets ensure that the turbo is fed with cold air. The second inlet on the S3 sits above the passenger headlight to get the air.


Forge Twintake Vs BSH True Seal:
As some of you will know previous to the Twintake I had the BSH True Seal intake on my car. This has put me in a good position to be able to compare the two intakes.

[FONT=arial, sans-serif]I do not think it is the placebo effect and the Twintake does feel stronger than the BSH. The initial delivery feels pretty similar but further along the rev range (from about 4k rpm) the Twintake feels stronger and I am sure it is producing more top end power. The sound is quieter than the BSH at WOT due to the Twintake being a sealed system. Under normal driving both intakes are quiet and you can bearly tell the difference compared to stock. Quality wise the Twintake is miles ahead of BSH and I believe it looks much better in the engine bay.[/FONT]


[FONT=arial, sans-serif]Minus Points[/FONT]
[FONT=arial, sans-serif]At the moment none for me. If you are after more sound then the Twintake may be a little quiet for some, personally I think it sounds really good.[/FONT][/FONT]
[/FONT]
 
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Cheers for the write up, would be good to stick mine on the rollers with evoms then try the twintake and see if it was worth changing. I think i would miss the roar from the evoms if i were to change it for the twintake.

Davie
 
You do still get a nice roar and whooshing sound from the twintake it is just more subtle because the filters are sealed compared to the open filter on the EVOMS etc.
 
Any chance of some videos mate? inside the car accelerating and reving with bonnet open? would give me an idea of the difference.

Cheers Davie
 
thanks for a great write up!! would like one...if i didn't have alredy CAI..... :)
is it me or the pipe diameter is smaller than first forge CAI???
 
david_phillips95 said:
Any chance of some videos mate? inside the car accelerating and reving with bonnet open? would give me an idea of the difference.

Cheers Davie
Click to expand...
I'll try and get a video up for you :icon_thumright:
 
Last edited:
Boydie said:
Awesome mate - good write up!

If I took my S3 to my local rollers, optimistic at best, my S3 would have 363bhp with stage 1 mods lol
Click to expand...

My S3 produced 330 BHP on AMD's rolling road when it was mapped to stage 1 and that was with the OEM intake. For me it just highlights the "dyno lottery" and that you should concentrate on the gains which are made rather than the peak figures.
 
S. said:
thanks for a great write up!! would like one...if i didn't have alredy CAI..... :)
is it me or the pipe diameter is smaller than first forge CAI???
Click to expand...

Not sure what the diameter is on the piping for the first Forge CAI however I would guess that it is the same - 70mm
 
That's a nice stage 1 graph, apart from the blip the torque remains all the way up there.
 
An absolutely fantastic write up. Really enjoyed reading it thank you.
 
Thanks for the kind words. The car really does feel fantastic to drive right now and it has left me wondering whether I really need to do much more to performance wise. The modding bug however has bitten me hard and I do not think I will be able to resist :haha:
 
You just need to update your signature now!!!

When I purchase my next car, other than code, the modding is over. Period. I'm going to write a contract!!

Just noted from your top photo, your oil cap isn't done up. I take it that it is now (mine sits side to side when done up, not top to bottom)
 
warrencox said:
You just need to update your signature now!!!
Click to expand...
Indeed I do!

warrencox said:
When I purchase my next car, other than code, the modding is over. Period. I'm going to write a contract!!
Click to expand...
Resistance is futile lol.

warrencox said:
Just noted from your top photo, your oil cap isn't done up. I take it that it is now (mine sits side to side when done up, not top to bottom)
Click to expand...

It is done up actually. When I first removed the engine cover it caught against the oil cap and separated it in half without breaking or snapping anything. So I put it back together and it ended it ended up looking as it does. I've tried separating it again to get it horizontal but I'm scared I'm going to snap it!

My advice would be to make sure you remove the oil cap before removing the engine cover.
 
KRL said:
It is done up actually. When I first removed the engine cover it caught against the oil cap and separated it in half without breaking or snapping anything. So I put it back together and it ended it ended up looking as it does. I've tried separating it again to get it horizontal but I'm scared I'm going to snap it!

My advice would be to make sure you remove the oil cap before removing the engine cover.
Click to expand...

Funnily enough I did the same, but there was a disturbance in the force when I got the glue out and it went back on looking as it did when it was factory (phew!). R8 oil cap anyone....:whistle2:
 
Excellent write up KRL. Funnily enough I fitted my new ITG intake this morning which replaced the old Forge CAI which had been on for about a year - so intakes are on my mind at the moment. There are lots of new options out there now which are making the old timers seem like relics of a bygone era. This looks great I have to say.
 
Enjoy the ITG Iggu!

I agree that CAIs seem to have moved on a level in the last year or so. The gains that can be made from an intake now are quite staggering. Like for me having stage 1 and the Twintake I have made the same sort of gains you would expect to make with Stage 2 plus a TBE exhaust.
 
Glad you are happy , thanks for working with us , the pipe diameter is still the same as the original deisgns , as we move into production this kit will be in black .....
 
Forge said:
Glad you are happy , thanks for working with us , the pipe diameter is still the same as the original deisgns , as we move into production this kit will be in black .....
Click to expand...


Just a thought here.....if the rest of the intake pipe diameter is the same as the original design,that implies that the main restriction in the original Forge CAI is at the level of the intake filter.

Do you plan to release either of the following:

1.A larger diameter,less restrictive intake filter.

2.A retrofit to enable the original CAI pipework to be used with the twin filters.
 
KRL said:
Here it is:
P2120388small.jpg




Why?
Fitting
Quite possible to fit as a DIY. For the more experienced DIYers fitting should take about 1 hour or 2-3 hours for the less experienced. I would not expect to pay more than 1 hours labour for the fitting if having it done by a garage.

[FONT=arial, sans-serif]Forge are taking the time to tailor the Twintake to the various VAG platforms rather than a "one solution fits all" intake. It must be a significant extra cost however I am sure it will show its benefits in quality and performance.

Other Intakes
There are many options out there:
- Carbonio
- ITG Maxogen
- EVOMS
- VF Engineering
- BSH True Seal
- Neuspeed P Flow
- Dblias
- ...

Performance
As part of the testing The Twintake was compared to the OEM intake on a dyno. Here are the results:
forge_twintake_dyno.jpg


Compared to OEM the Twintake made an extra 26 BHP up from 298 to 323.9 and 12lb/ft Torque from 285lb/ft at 3500rpm to 297lb/ft at 4320rpm. These runs were completed back to back within an hour of each other on the same rolling road. My S3 has no other performance mods apart from a REVO Stage 1 remap. At further levels of tune ( Stage 2 and Stage 2+) I would imagine that the performance gains would be even more compared to the OEM intake. The torque is giving nice gains across the entire rev range with more ‘area under the graph’ - the more area, the better the car will drive. Power does not look to be dropping off at the redline either, the car just wants to keep going! The turbo is spooling earlier with the Twintake - notice the power/torque lines are shifted up and to the left.

My car is suffering from a slight flat spot at 4400 rpm in both runs so please ignore this. It is something I will need to chase up and sort out seperately.

Driving around you can feel the performance gains. Throttle response has improved and it is at the top end where I feel the gains most. I've driven around 1000 miles with the Twintake installed now and the Long Term Fuel Trim is sitting at 4.7% indicating the MAF scaling is working nicely.

The sealed air inlets ensure that the turbo is fed with cold air. The second inlet on the S3 sits above the passenger headlight to get the air.


Forge Twintake Vs BSH True Seal:
As some of you will know previous to the Twintake I had the BSH True Seal intake on my car. This has put me in a good position to be able to compare the two intakes.

[FONT=arial, sans-serif]I do not think it is the placebo effect and the Twintake does feel stronger than the BSH. The initial delivery feels pretty similar but further along the rev range (from about 4k rpm) the Twintake feels stronger and I am sure it is producing more top end power. The sound is quieter than the BSH at WOT due to the Twintake being a sealed system. Under normal driving both intakes are quiet and you can bearly tell the difference compared to stock. Quality wise the Twintake is miles ahead of BSH and I believe it looks much better in the engine bay.


[FONT=arial, sans-serif]Minus Points[/FONT]
[FONT=arial, sans-serif]At the moment none for me. If you are after more sound then the Twintake may be a little quiet for some, personally I think it sounds really good.[/FONT][/FONT]
[/FONT]
Click to expand...

Am I the only one that seems to have noticed a transmission loss of over 130 BHP!!! 199bhp at the wheels, that is very low for a car that is supposed to be putting out 330 brake at the fly.
That's a huge loss in drag, somethings not right there.
 
This is not an Cold air intake but it has a seald intake which is nothing special... not worth the change over OEM, the kits with "OPEN" intakes are 10x better...
 
Read the review mate:readit:

I had filter on a stick type intake before the twintake and I can assure you that the Twintake is better.
 
Last edited:
mrgicm said:
This is not an Cold air intake but it has a seald intake which is nothing special... not worth the change over OEM, the kits with "OPEN" intakes are 10x better...
Click to expand...

we should all revert back to OEM as the setup is better than the forge twintake that from what KRL has shown made a documented 26bhp gain

what a load of S**T

please refrain from consuming drugs and alcohol before posting haha :laugh::laugh::laugh:
 
"This is not an Cold air intake but it has a seald intake which is nothing special... not worth the change over OEM, the kits with "OPEN" intakes are 10x better..."

MRGICM Where is the cold Air? Its outside the bonnet is it not? so your normal CAI is not quite a cold air system either as a lot of tuners position the filter a lot better than just infront of the battery box, most cut through and have the filter inside the inner wing but out side the engine bay. Now thats a CAI system in the true sense of the word!

Mind we are talking about the UK so it wont make too much differance where positioned in reality but every little helps as it where.
 
Talk is cheap.

Action speaks louder than words.

It's easy to judge something from a set of personal prejudices / ideals, but there are a couple of important considerations:

1) Forge wouldn't risk their reputation and spend an awful long time perfecting this if it was h0rse$h1t
2) KRL wouldn't risk looking like an utter n0nce by telling us the Twintake was 'the $h1t' for us to go out and buy it and then find out it was a bag of @r$e
3) There are figures on different sites proving this unit works well

I'd like to add at this point I will not be buying one as I'm happy with the ITG, BUT lately there seems to be an increase in the number of people dissing products on forums with little or no physical evidence. I'm all for people explaining why they think they believe it may not work, but to say it can be as bad as the OEM unit.... even my Carbonia was better than that!
 
akash_sky1 said:
Am I the only one that seems to have noticed a transmission loss of over 130 BHP!!! 199bhp at the wheels, that is very low for a car that is supposed to be putting out 330 brake at the fly.
That's a huge loss in drag, somethings not right there.
Click to expand...

Good question and a good spot! I decided to ask powerstation the very same thing and this was the reply:

the drag figures measured by our dyno are highly accurate and “real” whilst the car is on the dyno. I would say that around 10% of them is transmission losses and the rest is the tyres being deformed on the rolling road. This forms an exponential curve- the faster you travel the greater the drag.
Click to expand...

 
that's dyno lottery. i personally don't trust them. your car is pushing 330bhp with stage1, while mine with stage2 is pushing similar power...so there are your drag figures :)
btw. don't want to insult anyone.
 


Sounds quite meaty :)

Davie
 
Last edited by a moderator:
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HAHAHAHAAHAHAHAHAHAHAHAHAHAHAHAHA!

I want one of them!
 
We have some better weather here today so here are some more pics:

Side View
IMG_1433_ul.jpg


MAF - I'm very happy with the quality of the welds.
IMG_1435_ul.jpg


Second inlet above the passenger xenon
IMG_1436_ul.jpg


Factory inlet in the OEM position
IMG_1438_ul.jpg


Money shot
IMG_1439_ul.jpg


The filters
IMG_1442_ul.jpg
 
  • Like
Reactions: James__S3
looks perfect KRL, hopefuly we can get the numbers on the groupbuy.

Ill be putting my EVOMS Stage 2 with Evoms heatshield up for sale soon was over £400 from regal still have reciept and boxes if anyone is interested drop me a PM.

Cheers Davie
 
I was only saying my opinion as the most important thing a an intake is: how much air can it take? which is very much influenced by the position of the intake (final end), and that the path of the intake has to be as much heat resistant as possible. I hope you agree on this with me...

Now, since I DONT QUITE GET IT, can someone please explain what is the use of the air box on the right, as I can see where the left one gets its air from????
 
mrgicm said:
I was only saying my opinion as the most important thing a an intake is: how much air can it take? which is very much influenced by the position of the intake (final end), and that the path of the intake has to be as much heat resistant as possible. I hope you agree on this with me...

Now, since I DONT QUITE GET IT, can someone please explain what is the use of the air box on the right, as I can see where the left one gets its air from????
Click to expand...

The maximum air flow is governed by the most restrictive part of the system,and if for instance there was a narrowing in the induction piping,or a very sharp bend,causing turbulent flow,then the overall flow will be reduced.

What Forge have done is to put 2 induction filters onto one inlet system effectively,and since by their own admission the rest of the intake system has the same diameter as the original Forge CAI,that points to the inlet filter on the original as being the point of flow limitation.

Obviously other factors such as air temperature and pressure do play a part,but since the only factor that has changed with this system is the twin intake filters....
 
this leads back to a question i had in another thread with regards to the MAF sizing as it appears to be the most narrow part and as alex points out this will govern the maximum air flow which is why i was surprised when i saw the step down in diamter on the ITG filter when it came to the MAF. I was actually surprised at how small it was in comparison to my astra vxr which used an 80mm MAF
 
Last edited:
It's unfortunate that the VAG car comes with a 67mm MAF housing diameter as standard. Another limitation carried over from the OEM air box system.

I was expecting by now to see a larger intake pipe produced (maybe up to 80mm), with a fully adjusted remap code to compensate for the new scaling, but then I guess it is a lot of work for the amount of people likely to shell out.

I wonder whether there is a limit to how big a pipe you can get beyond the MAF which bends down behind the engine block.
 
I believe APR's stage 3 system usess a 3" MAF which they have calibrated for. Also GIAC have release a specific tune for the VF Engineering intake.

Personally I believe that unless you are going BT you really do not need a larger MAF housing as the 67mm pipe flows more than enough air for our K04 turbos.
 
audi upgrades
I agree KRL. All of our Stage 2+ cars are seeing over 360bhp which is pretty much the limit with the K04 and Stage 2+ software anyway. The reason I went from the old Forge CAI to ITG was to get the extra 10bhp at the very top end (from 360 to 370). But even if you put a drainpipe onto the turbo inlet (through a hole in the bonnet) I personally don't see you'd get much more power from the intake system alone as the turbo is maxed out at this point anyway.
 
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