I hear ya loud and clear. I just wish I either had a) enough spare time to perform this myself or b) someone closer than 1200kms away to do it. Do JHM have an affiliations with any workshops here in Aus CV?
I think I just need to take a couple of days leave and get in and smash it.
Great point, I think this is mentioned somewhere. The JHM tune actually turns up the safety adjustments and expands on the cars ability to adjust for issues like elevation and temperature. The triggers on the JHM tune are set to be reached at a lower limit.
Also, just to add regarding the pulled timing, my plan to relocate my Aquamist system onto the RS4 is to log the difference when you alter two of those most critical knock prevention characteristics - in-cylinder temps and fuel octane rating. Some of the other factors are just plain out of my control (stratospheric 12.5:1 engine compression being one lol).
Guys thanks a lot for the info.
Apologies if this was discussed at an obviously wrong thread.
As said i am about to install the JHM tune, so we will be talking further i guess on what ii expect to be my great impressions!
I started a RS4 investigation thread. Guys with stock RS4s experience ping issues. From the timing pulling you can see the heat really effects these cars. The JHM tune helps make power and keep the cars safer but in extreme heat you want to make sure you help get as much heat out of the motor as possible. Piggies intake spacers and keeping up on the carbon fuel filter replacement is only going to help. Tuned or not.
I think you’re right JI. I’ve just recently noticed, now that it’s heating up here that i’m starting to get pinging on light throttle inputs when the engine is heatsoaked. Well past due for carbon clean and some JHM spacers.
if u have the funds to buy a walnut shell blaster u can do the carbon clean yourself. removing the intake is fairly easy. lots of ppl have done it using solvents like seafoam, carb cleaner, oven cleaner and so on. its a real pain in the ass but can be done on your own just takes time. with the walnut shell blaster it can be done in a few hours.
Hi guys, I know this is an old thread, but thought I’d give a quick update. I’ve finally had enough time on holidays to do the carbon clean and install some JHM intake spacers. I’ve also replaced the valley pan gasket, and the two different oil filter housing seals as I was getting some pretty decent oil leaks from the valley area.
First, man, what a PITA job. I was definitely taking my time and couldn’t dedicate all of every day on it, but it still took 4 days from start to finish.
I went down the zip ties and oven cleaner route, and this was time consuming, but ended up working well after several soakings and scrapings.
Once the manifold came off, I can pretty much guarantee that this engine has never been cleaned. I’m up to 180k kms now, and the carbon buildup was unbelievable. I’ll post up some pics later once I upload, but several of the ports were totally occluded on the top and left hand sides of the port runners. There was really very little actual room left in the ports for air to flow. The build-up was way worse than any other pics I’ve seen in all my research (including 2ManyToys buildup with his leaking valve stem seals, and a pic from a South African RS4 for 160k kms on it). Having seen it with my own eyes, I really can’t believe the car was even managing to run, and run smoothly at that!
Anyway, once I had everything back together and buttoned up, cleared the codes from the sensors being unplugged, everything is running fine. Took it for a run around the block and holy sweet mother of god, there is a huge difference. I was unsure what to expect as plenty of people had a clean and didn’t notice anything, but it is extremely obvious in my case. Torque down low is much improved (spacers likely helping here), but top end is absolutely phenomenal now. I used to get an exhaust note change and a small pickup when the throttle opened up 100% at 5500rpm, but now it’s literally like a turbo coming on boost it’s that viscious!
I haven’t done any follow up datalogging yet, but I took 3 good back to back 3k-8k pulls at 20degC ambient temps for before after comparisons. I’m waiting to get another 20degC ambient to use the same stretch of road to run another 3 “after” runs to compare the carbon clean back to back. My gut is telling me I’m going to be seeing a lot less timing retardation and a pretty healthy boost to MAF volume, and hopefully a look in at an 8.x time.
I’ll definitely post up the pics and extra datalogging results once I have the info collated, as I’ve never found any objective and comprehensive before/after VCDS logging on a carbon clean anywhere on the net.
Good to hear it all came together. Carbon cleans take a ton of time and can end up breaking a ton of stuff along the way. After a few days re check the intake manifold bolts to make sure none of them backed out. They tend to back out after a few heat cycles so it might be good to look into that.
Cabon pics would be neat to see. The thing that is so hard about the carbon issue is that no two cars are going to have the same amount of carbon build up so you are never going to get everyone to see it the same way. Pictures will definitly help show how bad carbon can get.
Thanks for the update
Here are some pics off the phone for the 8 ports. One of which the focal length is off. I have some more on my DSLR which I’ll get off later (have been on leave). Also hoping to get some datalogging runs tomorrow night as the ambient temps will be the same as the before runs.
Ok, just got back from doing some more datalogging runs.
The data definitively backs up the seat of the pants feel, and I’m now back into the 8.xx second range for 3-8k!
Pre clean runs were around 10.5 seconds 3000 - 8000k RPM runs
Post clean runs were very repeatable at 8.9 seconds. Which seems about bang on the money for an Avant, two up, full tank of fuel and 22deg C ambient temps.
I also went from an average of 8.4 degrees of timing retard across first 4 cylinders between 4000 and 7000 rpm, to only 2.8 degrees pulled timing. Showing definitively that carbon buildup significantly increases timing retardation.
The highest MAF reading I reached pre clean was 139, and post clean, peaked at 162. A huge (and not surprising) increase in air mass moving through the engine.
Also of note is that even though the ambient temperature was almost dead on 2 degrees warmer post clean vs pre clean, the effect of the JHM intake spacers showed IATs of around 2 degrees lower, showing a good effect from insulating the intake manifold from the engine block heat conduction.
So end result, is absolutely phenomenal, in both seat of the pants feel and objective data gathering. It’s also pretty amazing that this car at nearly 190k kms is still pulling so strongly after a good carbon clean.
Here is the raw data for anyone who is interested: https://www.dropbox.com/s/8r0h4hmemqf67di/Carbon%20Clean%20BeforeAfter.CSV?dl=0
Yuck, ;-p glad that is out of there! Have fun, very cool that it’s running that well with higher miles as well
Wow that was terrible. Great work and great updates. Nice to see the car is running strong again.