RS246.com Forum :: The World's #1 Audi R, S and RS Enthusiast Community

Just a brief write up at this stage with more detail added later as I'm busy prepping for tomorrow. Since my car is now not a daily commuter then I struck a deal with Glenn and his team at Revolution to be the guinea pig with regartd to some engine development work. So with an IM I 'acquired' I left it for them to deflap (tumble flaps), port and polish along with my car.

So last Tuesday the Revolution team set about cracking open the engine and fitting the enhanced IM. I will post some pics up later of the level of carbon in the valves but suffice to say there was a fair bit. Bear in mind that this was a car that 2 weeks ealrier did 400PS / 394.1 bhp so more to the discussion that carbon build up can exist without being totally detrimental to the car, particularly on one with 85+k on the clock. Whilst the manifold was off the guys took a borsecopr and look at random chambers and they are all clean as a whistle so good news there.

Whilst in they also fitted my skimmed rear discs as I was getting highspots after 40k miles on the EBC's and they fitted a new wing mirror housing for me as well. So got the car back on Thursday, but having driven an Ibiza 3 pot TDi for 2 weeks I had no idea whether it was running better. So went to Motoscope on my lunch yesterday and got the following results;

Pre port / polish
Post port polish
This was using the same tank of Tesco Momentum 99 and all factors the same as could be regulated.

So a good result all round with a net gain of 13bhp taking me up to 407.1bhp, with V-Power I will probably get more torque out of the engine. So a big thanks to Glenn and his team at Revolution, very professional, kept informed and got to see first hand what they were doing and now they have the skills and a donor IM for those who maybe want to venture down the same route. Other stages of development to follow soon.

Interesting stuff. What else is on the cards?

Have you got some pics with the manifold off?

R&D Piggy Bank is empty at present, further development funds permitting later.

Good results there.

Where is revolution? Do you have the address? Thanks.

these look like fairly accurate, repeatable and representative results
the 'after' runs were cooler and with a higher pressure, so should make more power...Cf 102.7 vs 101.7% (5C temp difference)
but we can say ~12-13 HP
~2 lb ft torque
car was uncleaned 85k miles
after was cleaned, ported, polished and de-flapped for a 3% HP gain and <1% torque (does the flap help torque? imo yes)
so if we say 1/2 is port/polish/de-flap and 1/2 is cleaning, carbon on an 85k mile car cost ~1.5% or 5-6 HP, but I'm guessing the port/polish/de-flap was almost all the gain and the cleaning hardly any...

the reason I think the results are valid (or at least repeatable, if not exact acccuracy) is the lower ramp rate allowing the engine to load up and adjust properly and make near max power...

using my correction calculator for the given conditons (assuming a rh of ~60%) I get 102.7 for before 1.00 for after...an almost 3% difference which would negate almost all the gains, ie, the engine made essentially the same power before and after
even if I take the humidity up to 80% the after is still only 100.7% a 2% difference....if we assume 1/2 and 1/2 port/polish and claen, 1% for cleaning ~ 4 HP
http://wahiduddin.net/calc/calc_hp_abs.htm

Only 1 problem - Graeme didn't have the valves cleaned, only exchanged the manifold. Therefore the cleaning is yet to release more power & torque?

after re-reading I see he didn't say he cleaned it, but that I assumed so after removing everything (3/4 the battle, the rest is elbow grease)
so manifold P&P/de-flap ~3% and if you equalized Cf's, essentially 1% or so...
these engines must have a very high vol eff to begin with because it is hard to get any power out of the conventional methods (tune, P&P, exh, etc.)
that's what a 12.5:1 Cr, 2 inlet valves, DI and an extremely advanced ECU/control system will do for you...
3% is a ~50 pounds of weight (8 gal of fuel) or 5 deg C in temp...
a 1000' ASL is 5%

brett123 wrote:Where is revolution? Do you have the address? Thanks.

You'll meet Glenn tomorrow as he is part of the NE convoy going to Malton. He can give you all the info. you need but they are based in Dunston / Gateshead

As caldy said Arthur, no cleaning as yet. I wanted to see what porting polishing did and cleaning as separate processes because everyone I have seen who has had this done previously have had the two done toghether so you cannot distinguish which produces what. Now ideally we should have perhaps cleaned, dyno'ed and then ported / polished but the guys at Revolution are researching the best cleaning material to do this and the IM was already available. If and when we get to cleaning (not sure I want to given the car now does within 7 bhp of rated on a dyno and more torque) then the p/p will skew the effect of actual cleaning by a factor but it should give a good representation.

These are the pictures of carbon in an 85k mile car









Some other pics;

Donor IM before surgery



Laborious work.....



And the result...

mine looked almost the same...50k miles
after cleaning I can discern no difference in speed (3k to 8k), all runs within 1/10 of pre-cleaning, same road, same load, same temps, or efficiency, MPG has not changed even a tenth...now I may have a picked up 5 HP or so but that is easily lost in the noise...

Not bad P_G, was thinking the CB would be a lot worse.

So the secret would appear to be run your car regularly and run it well with a degree of mechanical sympathy and plenty air / speed.

P_G wrote:So the secret would appear to be run your car regularly and run it well with a degree of mechanical sympathy and plenty air / speed.

yepper
and warm it up as fast as possible without abusing it...
I redline a dozen times a day...gradual throttle, medium load...the noise is amazing
5k oil changes, nothing but Shell 93

Great result P_G
I think it was possible to keep going and remove every single rough edge from the manifold but after 6hrs of work we felt we'd done enough and stopped.
I didnt think we would have been able to remove that much excess at the initial stage and unsure of the reults for the hard work put in but there are lots of rough edges where the unit has been cast and when we do my car we will collect the shavings in a jar and take a photo....results speak for themselves too!

brett123 wrote:Where is revolution? Do you have the address? Thanks.

Hi Brett
Our address details as follows:
Revolution House
Clockmill Road
Gateshead
Tyne & Wear
NE8 2QX
T: 0191 4619200
e: keith@revolution247.com (sales manager)
e: workshop@revolution247.com (workshop manager) also a Glen

Were based just south of Newcastle and only 3 mins from the metro centre shopiing mall - please feel free to PM me but I've but both my managers down as contacts as you will get a quicker responce as they're always telling me off for getting involved with sales.....LOL

Glenn