Very similar but biggest difference being dry sump in the r8, other differences like intake don’t relate to strength.
I actually just started a thread about the RS4 and its limits (to see what we know/how close people have come)
The biggest ‘claim’ I’ve seen is 600 whp from a Heffner kit on 100 octane, stock motor and just their turbo kit bolted on. That’s an old claim though, and I haven’t seen it backed up with anything. They dyno’d 536 whp on 93.
The biggest dyno I’ve actually seen posted is an EPL tuned Heffner car with upgraded fuelling making 550 whp/460 wtq. Of course that’s just a dyno too. EPL described it as +50 whp over the standard kit, so I get the impression the RS4 fuelling is unch on the Heffner kit.
I still haven’t seen any (and I mean ANY) quarter mile times for an R8 4.2 Heffner car. If you guys have seen anything, or know anything, add it to this thread.
Friends of mine that own a well known VAG shop actually installed a Heffner kit on a local R8… Apparently the car goes like stink, but I doubt it will ever see track time.
I did hear that EPL’s tune is far better then what comes with the kit (I believe APR?), but haven’t experienced it myself so yeah. I did try to convince them to try the EPL tune on the car and a friend of mine (Don R) was in talks I believe at one point with Tony.
Maybe I can convince someone to run the car at Cayuga one day just for fun.
I wasn’t aware there was still fueling options? Are the injectors from the V10 used for that?
I think its uprated high pressure fuel pumps
^^^sounds familiar. I didn’t have time to read the whole thing from epl
I run upgraded internals on the hpfp’s on my b7 rs4 saki they come with the tts kit
Yes forgot about the upgraded pumps… but still you hit a limit with injector flow even @ high rail pressures.
I think the injectors on these fsi cars are superoverkill stock. Might be why you don’t hear much about them being upgraded.
The b6/7 s4 needed injectors I believe on the jhm kit. That’s making about 425 whp…or about 160% of stock
A strong k04 b5 is making what…375-.400 whp? That’s already 200 percent of stock power, so upgrading is a must.
Rs4 at 500 whp is ‘only’ about 150% of stock power…and its an RS so the overkill/overengineering vs stock levels is probably going to be greater than the S cars.
We’ll see I guess. Jhms blower is capable, in theory, of about 650 whp.
They do flow enough for a fairly good power gain, but you will hit a limit and with the talk of big S/C’s and I would assume eventually built motors to push the S/C’s to the limit, fueling will become the next issue on the DI cars just as it has with other smaller VAG engines.
This is why the UGR cars are running a Motec piggy back system actually.
Its hard to compare FSI injectors to standard ones. Keep in mind the RS4 injectors (4 of them) can make about 400whp on 2.0T FSIs. I would assume with a bigger engine and 8 of them they would have some headroom.
Like you said though injectors are not everything and they do need HPFPs as well as LPFPs
Yes for sure. Running out of adequate fuelling is inevitable.
Which ugr cars? The r8 5.2 setup? Or others?
Anyone know anything about the rs4 fuel pump? Anything like the 80 billion psi setup on the n54 cars? S6atron was telling me how crazy they are on that car.
probably about the same, all the DI pumps are fairly high pressure
So the upgraded intercoolers made a big difference.
still only at 32 psi now on er’s (red) vs 29-30 psi on ebay fmic (pink)
http://i714.photobucket.com/albums/ww142/judeisnotobscure/77029psifmicvs32psier.png
Yikes that’s a pretty huge difference.
Wonder if conditions or any other factors changed.
Whens he going back?
iat’s were 30*-40* cooler on the run with the er’s 
amazing what a set of intercoolers can do.
Hopefully returning to the track soon… gotta do some exhaust testing.
ebay fmic (pink) vs. Er’s (red)
http://i714.photobucket.com/albums/ww142/judeisnotobscure/770ervsfmic.png
Conditions the same though (ambient temps)?
Conditions the same though (ambient temps)? Notorious vr recently said he didn’t really feel there was a huge diff between ebay fmic and ERs.
Temps should be within 20*
Temps with the er’s should be higher since they were more recent and the fmic logs were done in early april. both at night near Boston.
I don’t believe NVR would say such a thing. The difference is clearly huge.
Response time should be better too with less charge piping. That means quicker re-spool and hopefully quicker 1/4 mile
Wow… nice to see the diff. Now he needs better exhaust 