Remap and Intake OR Remap and cat back?

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Faz786

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In two minds what would give better bang for buck.

What are your experiences guys and gals?
 
I have the same question, for an Audi TTS (I believe its the same engine as the S3)
 
Someone said to me that first thing should always be the CAI then a remap.
The better option is CAI,CAT-BACK and a Remap :beerchug:
 
Other way round...Remap stg 1 and you dont need a CAI TBH on a S3
 
So the greater gain is from a catback and remap rather than sticking an intake on and remapping?
 
If your looking for higher BHP figures remap and CAI is the way to go, If figures dont wory you get the remap and put on the exhaust for a better note
 
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I'm ok with the exhaust as is, but would defo like to make the most of the extra power that can be achieved via a remap

However, not quite on budget to get an exhaust system also
 
Miltek cat back fitted 3 weeks ago, revo map this weekend, hopefully will feel completely different by 10am this saturday
 
Cat-back doesn't really make much improvement in power or torque, most of the back pressure comes from the downpipe and cat ( and turbo of course). So for performance, remap and CAI first, but the cat/downpipe deffo need upgrading to, to complete the improvement in gas flow efficiency.
 
paddy said:
Other way round...Remap stg 1 and you dont need a CAI TBH on a S3
Click to expand...
Erm I disagree there. Generic stage 1 maps don't account for a CAI hence you dont need one, but that's not to say a CAI wouldn't give you any benefit even on stage 1. Low end torque may be sacrificed slightly without proper mapping, but improvement in throttle response would be night and day and even a bit of top end power still on stage 1.
Standard airbox is designed pretty much to dampen the noise of turbo spool & the DV, crap for air flow.
 
Sorry but i would want to see flow figures to prove the "crap for air flow" statement. All the RR figures i have seen for an S3 dont show an appreciable difference with a CAI on stg 1 let alone on a std engine and i did say "other way round" ie: stg1 first then CAI. I would not want to lose "ANY" Torque at the bottom end at the expense of a a slight increase in power at the top given i drive on the road in the real world of traffic and restrictions and not on the track. sorry but small increases in power at 6k rpm are pretty irrelevant for 99% of drivers. peak rev performance is not always the characteristic you want from a good engine...One reason i sold my last 4cyl 12k rpm bike was 4 seconds after dumping the clutch i had broken the national speed limit, 6 seconds and i was in licence ban territory. Where is the fun in that ? i bought a Ducati with the same performance but bucket loads of torque at speeds and revs you could use it, brilliant fun :)
 
Decent Stage 1 software only will make 310bhp ish.

Stage 2 will require CAI and Turbo back exhaust, (and software to match) when budget allows.

Personally I wouldnt bother with in between measures, stick with proven upgrade paths when funds are available and get the benifits without the hassle. Until the clutch goes that is....

Good luck
Paul
 
paddy said:
Havnt found i have need more yet Paul :)
Click to expand...

Agree, I ran Stage 1 for 3 years up until I sold the car and never felt wanting at all.
Its a perfect tune for the rest of the car, brakes, chassis etc always seemed to hold up well. Although I did tighten things up with H&Rs to give the car a bit more attitude but they werent essential.

Like most with the tuning bug, I thought about Stage 2/2+ but the thoughts of clutches, possible mis fires, valves spring issues, catch cans, more frequent oil put me off. Not to mention the hassle of resale and putting it back to stock.

I have driven (drove?) Auldreekies Stage 2+ S3 with Coilovers and ARBs etc and it is a proper weapon so I can see why some want the extra grunt that comes with Stage 2/2+.

My advise would be to go for Stage 1, making sure you choose software that provides an upgrade path. (just in case!). Most will find that 310bhp is plenty.

Cheers
Paul
 
Gains in top power are marginal yes till you get proper software to take CAI into account but improvement in throttle response, from the shorter, bigger intake tract is HUGE and very tangible, and IMO makes fitting one before a CAT back very worthwhile.
Driving with the standard airbox back on feels like throttle pedal has been fitted with a time delay. Also Paddy it was really the improvement in throttle response that I lauded over any marginal top end gains, and this does of course make the car much more enjoyable.
 
I would love to try one some time. I have considered an CAI and seen very suspect pressure tests from the std intake track showing negative ie:vacum on some areas on bends which is a disaster at high flow. the same report said the real gains were in the cold intake rather than in the flow on a std engine so that would apply at stg 1 as well. My feeling is go for it but in relation to post 4 i would do the map first. I have never been one to see a lot of point in flowing air in if you dont flow it out as well and if you are going to do that you might as well go stg2 straight away.. Interesting view on the throttle response akash....Food for thought mate :).
 
My ITG goes on the car today,will tell you how are the results on totally stock car!!!
 
Well i must say that i'm really really impressed with ITG!!!
I love that wooooosshhhh sound and noise from stock diverter valve is amazing,
when i will fit the Forge DV,it's goona be christmas everywhere lol :jester: Lovely sound!!!
Car feels much more alive and the throttle response is a little bit better,
the turbo hole remains but in the middle rev range is faster spooling up all to the end!

Money was not thrown away! Highly recommended:arco:
 
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pinterovski said:
Jontymo,what numbers are you hoping for?
Click to expand...

Between 300-310 up from stock 272, hoping it removes some of the lag with this engine/turbo.

I've not gone for any air upgrade as only really needed for stage 2 and not bothered going there(will change for a TTRS in time for this upgrade)

Roll on tomorrow morning
 
will revo improve normal driving i.e smoother power delivery or is it just a case of pushing the car to the red ?
 
Interesting thread. I have always thought fit the modifications to the car, then get it mapped to suit, but that would be mapping for that particular car with on road testing and set up on a RR, not a stage 1, 2, 2+ etc. My S3 will be getting mapped soon, insurance is due so I have spoken to them and the warranty is almost out so it wont be long but I am a little wary/intrigued by the one map suits all philosophy but a lot of research has gone into it and thousands have been sold and I will probably be going Revo as there is a dealer fairly close to me.

To keep things on topic, I think gains from a CAI will depend entirely on how restrictive the original air box is. Most gains will be made from changing the cat to a free'er flowing type but then it sounds like you are heading into stage 2 territory with the added expense of the cat and any ancillaries you may need. As you have only mentioned a cat back then I would probably head towards a CAI, providing that keeps things within the parameters of the stage 1 which is probably what I will be doing. For me, stage 1, then do a bit of research into how restrictive the original airbox is (if at all) then CAI.
 
With revo 1 and an SPS switch you can alter the map to suit bolt on extras later. Personally i dont want the added noise of a CAI or the expense of junking a perfectly good exhaust system for noisy alternative. stg 1 revo does all i need..after all how fast can you really go ? I appreciate that tuning is fun and getting every ounce of performance out of a motor can be a life's mission for some but reality is........its always a trade off. I did 400 miles yesterday, i can drive with the flow, i can pin myself in the seat to overtake and i did a 150 mile stint on Cruise through the night at 85mph down the M11/M25.and got ave of 33mpg for the 400 miles. :) I can break the national speed limit in 6 seconds...and i dont have a load of gear to strip off the car when i chop it in. win win
 
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I love the noise of my intake and exhaust, especially when its cold, there not too loud I as still have the OEM votex back box on and the intake is wrapped in heat reflective tape. At higher speeds its still fairly hushed even at high revs, on the inside anway, good balance of noise and refinement.
The 'raw' mechanical edge they bring is nice, letting you hear the turbo spool and deeper exhaust note, with very mild pop/bangs on overrun, otherwise its just a boring , refined, in-line 4 noise.
Still have memories of driving a 360 and Murcielago at full chat on a track, different sounds but both amazing, and my cousin's NASCAR-like Pontiac Firebird Trans-Am WS6 with a stainless exhaust, ****** amazing.

In the future when everything's electric, or some kind of turbine driven hybrid, we won't have any such music, so lets enjoy while we can.
 
Well what a wasted morning, got to Vortex, Mike hooked up the laptop only to find no map for my11 TTS only for last years model(think they changed from 268 to 272 bhp)!! so he has downloaded the code from my car and sent to Revo, hopefully Revo will have a map ready for next week!!!

So off to Awesome to get my miltek non res catback that i bought from them a few weeks ago realigned, the fitter had a good go to no avail, the quad pipes now look correct at the back of the car but the connecting pipe is still wrong with no way of it sitting against the car under body so just sits there like a big lump ready to bottom out, phot's taken and sent to miltek who need to get sorted quickly or its back to the standar pipe refund and hunt down something better!!! also noticed the connecting pipe had worn against the prop shaft and has a small gouge in it!!!!!!!

Still smiling though even with over a grands worth paid for and its all wrong LOL

More to come

Jontymo
 
Yea i go along with you Akash re noise on some lumps. My 3.2 was just superb with the Remus exhaust but the old 4 pot will only ever be a noisy 4 pot to me. I did fit a CAI to my VR6 a few years back and it sounded like an assmatic cow with a bad cough. I would want to hear a S3 with a CAI before i bought one. Which are the quietest ? do you know. I quite fancy a CF twin take and a CF engine cover purely from a looks thing .
 
paddy said:
Yea i go along with you Akash re noise on some lumps. My 3.2 was just superb with the Remus exhaust but the old 4 pot will only ever be a noisy 4 pot to me. I did fit a CAI to my VR6 a few years back and it sounded like an assmatic cow with a bad cough. I would want to hear a S3 with a CAI before i bought one. Which are the quietest ? do you know. I quite fancy a CF twin take and a CF engine cover purely from a looks thing .
Click to expand...

I don't find the ITG very loud. The best way I can describe it is just cruising along going through the gears you can hear a slight sucking noise from under the bonnet, then put your foot down and the engine noise is just a bit louder and the intake gives off a nice fluttering noise when you back off on full boost. I wouldn't describe it as loud or intrusive.
 
GNJ_Motorsport said:
I don't find the ITG very loud. The best way I can describe it is just cruising along going through the gears you can hear a slight sucking noise from under the bonnet, then put your foot down and the engine noise is just a bit louder and the intake gives off a nice fluttering noise when you back off on full boost. I wouldn't describe it as loud or intrusive.
Click to expand...

Agreed, same with the twin take :)
 
I would always say do the exhaust first.

First of all, cold air input is far less important when the car is moving. If you install a temp gauge and log under bonnet temps when actually on the road, you'll see that they are pretty much ambient when on the move. The dyno (which should NEVER be used to compare one car versus another (or even the same car as a before and after strictly speaking) very much flatters the effects of fitting a CAI, as the fans are never up to the job of replicating real airflow.

As far as volumetric efficiency is concerned, smoothing the exhaust path is more valuable then the pre turbo intake path as restrictions when the air is at or around atmospheric pressure have a far less significant effect than after you pressurise the gas and heat it to around 1000 degrees!

I tend to question the value of any CAI kit. Over the years they have only ever shown themselves to be about under bonnet bling rather than being actually useful.

If you want to improve flow, concentrate on the pressurised side of the gas stream and then remap.

btw. on the gtr, a decent cat bacl exhaust fitted after the primary cats in the highly restrictive stock downpipe can still yield an extra 40 bhp, even without remapping!

I know its a much more powerful car to start with, but the point to bear in mind is that even if you dont remove the smallest restriction (the cats) doesn't mean that there's no benefit from improving the rest of the system.

Imagine a hosepipe. blow down one with a 1cm diammeter, and then a 3cm diameter that has been pinched somewhere along its length to 1cm. Do you think they'll be just as dfficult to blow down? The answer is no, because the 1cm restriction in the larger pipe only occurs for a very short length, so its contribution to the back pressure is much lower than if it were along the entire pipe.

Lame analogy i know, but at least you can imagine it!
 
Adamantium said:
I would always say do the exhaust first.

The dyno (which should NEVER be used to compare one car versus another (or even the same car as a before and after strictly speaking)
Click to expand...

Would you like to explain this ? I would have thought the whole point of a dyno was fault diagnosis and with out before and after you will not know if you succeeded.

I used a Dyno for years in motorcycle race tuning and i cant off the top of my head think of an alternative for getting the set up right without before and after logs.

I do however agree about CAI. they move the figures around but as you say the results are usually Dyno logged and that is never realistic to pressure and flow on the road. its quite possible ( unlikely) that due to aero dynamics of the front of the car you could have a vacuum formed at points on the grill that would effect the air intake :)
 
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Engine dyno is a brilliant tool.

I trust those fully, but even then I would only trust figures from the same dyno.

rolling roads are completely inconsistent.

There are too many variables that can be altered due to the way they are operated.

Without changing any settings I have watched the same car appear to spool its turbo 500 rpm quicker, just by the operator showing me the different ways he can perform a run.

Add in to that ambient pressure, tyre pressue, humidity, etc, and although you can compensate for them, there's just too many variables than will make your number meaningless.

Hub dynos are a better option, and even then, only for measuring power at the wheels but ultimately you can only really trust the engine dyno and the velocity when you cross the line on the quarter mile to give an indication of power.
 
Yea operators can tamper loads with rolling roads. IATs make a big difference to and also it can vary depending on where the operator places the inlet probe.

Not long ago i saw some poor figures at inters on a rolling road. i loved the way the operator tried to sell the owner software to up the power and prove he could up the power. I however knew that the ecu couldnt be remapped properly without a standalone aftermarket ecu.

Back to the ops question, i would go generic stage 1...Then if you ache more power get the turbo back and relevant hardware with a stage 2 :)
 
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