High Mileage B7 Dyno Results

[Doug_S2]

Here we have a 78k B7 RS4. Driven sensibly most of its life cruising on motorways. New owner expects it to be better so gets it remapped. It gets mapped and feels better and more torque - This was before we had the dyno.

So the customer wants it dynod, and becasue of high miles he wants it cleaned and ported.

So the dyno plot tuned but untouched internally:

[Doug_S2]

Now we cleaned and ported the manifold and redynoed - which is run 1. Then we made a few changes to the map since it was so different from when we originally did it and it ended up being the 413PS

[Doug_S2]

some pics of the inlets - this car had large deposits on the flaps that were nearly touching the port side andthe valve stems

[Doug_S2]

more

[HYFR]

so i get this right....

78k mapped RS 4 gets 302ps on the dyno (corrected)

my 74k RS 4 got 371ps on the same dyno (corrected)

[Doug_S2]

Mapping does not fix the issue of restricted flow in the ports - if it does not flow the air or it does not run more timing then you don't get gains.

[pippyrips]

I still find it hard to understand how build up like that can be classed as acceptable with no side effects, even with all the formula in the world as back up.

[P_G]

Mapping does not fix the issue of restricted flow in the ports - if it does not flow the air or it does not run more timing then you don't get gains.

A couple of things Doug. There is a run 2 on the second graph which shows 400.5 PS, is that cleaned and ported prior to you altering the map tables of your remap? Also the car appears to be achieveing peak power at different RPM on different runs? Run 1 pre cleaning at 7554 (14:07 pm)and Run 3 at 6755 (18:04pm) , nearly 800 rpm difference? Then graph 2 run 2 is at 7321 (18:59pm) and run 3 back near the original run 1 at 7571rpm (19:10pm). And what is the new maf3 message about?

Also, I think what aka_dk was getting at was his standard cars produciess more that your customer's car that has a remap on the same dyno by some 70PS?

Like you say and it supports what has been said before, cleaning and porting does have a marked positive effect on performance, however still doesn't answer whether it is taking it back to standard or whether it is temporarily increaing rated performance.

[ArthurPE]

that indicates 300 crank HP
sorry, no way

400 after manifold/cleaning
then you got 415 after cleaning/manifold and sw rev?

the flaps were stuck, classic curve

I notice no full data panel on the 'after', as was displayed for the 'before'

[ArthurPE]

so i get this right....

78k mapped RS 4 gets 302ps on the dyno (corrected)

my 74k RS 4 got 371ps on the same dyno (corrected)

was yours cleaned?
or mapped?

[ArthurPE]

'before'
pre AFM losses ~ 31%
after AFM 24%
almost a 30% difference?
but power and torque ~ the same...

has this car run a 3k to 8k test before the work?
can you say who's car it is, if so?
based on those numbers (300 crank and flat >5500) >10 sec

based on the 50+ cars I have data for none ran near 10 sec
and only a few 9 sec
one was in 120F+ heat, his average was ~ 8.8, corrected <8.5
the other had a passenger, avant and didn't goose it until 3000, rather than 2500, still ran ~9

I have many uncleaned cars >50k miles, running the same time as cars just cleaned
2 recent cleaned cars (and modded)
avg corrected was 8.4 or so, one by vagcom, the same as the average of uncleaned, unmodded cars, well within the std dev...

[Doug_S2]

It passed the flap test. they moved ok - but possibly not fully.

run2 is chucking it back on after cleaning and porting - not touching the map - 400.5.

peak power is at different rpm becasue the power curve flatens off and you get very close to peak power of a wide range of revs. the losses are just one snapshot at whereve htat peak number was - the loss curves are all very similar - that number confuses a lot of people think ther eis a diffenrt loss but it is only becasue losses are at differnet rpm.

Of course a standrad car produces more - it propably flows more than 138g/s per bank like this car did. after cleaning and porting on the same map it did 184g/s per bank. Mapping a car is not magic - you cannot get more than what is physically happening in the engine.

Cleaning is temporary fix - I dont think I we have ever said it is permamnet. I think this just shows there is a big differnece depending on the build up.

[rsierra]

Based on those and other pictures I've seen, the deposits don't appear to be self limiting as postulated here.

[ArthurPE]

look at some pics of 20k mile cars...no significant difference
then look at the 2k pics...
the 78k are NOT 40 times more than the 2k, let alone 4 times the 20k
in fact, the 2k look like the 20k, and the 80k are very similar

in fact for 80k, those do not look too bad...and I can't figure those are causing a 15% difference in area... (as derived from the g/sec before/after)

there were other issues at play here, most likely the flaps...there is an SIB out on them
won't set a code, only impact performance

[Doug_S2]

I am not here to argue like others - they are the results from that specific car.