Regarding the CPS unit the overflow reservior only drops after extended periods of hard acceleration (i.e. after a full day at the strip) it drops about 1" and once the car cools it comes right back up. I have zero air bubbles floating to the surface.
What I meant is if you opened the cap, with the car running, if you have air in the system, the level will be going up and down, up and down, up and down, as you look at it.
Bear, you can pick up a few feet of clear PVC hose from crappy tire, run it from the bleeder valve to the open reservoir, and with the car running crack the bleeder valve until you see flow. Let the car warm up, and give it some throttle. See if that does anything.
I don’t see a way to bleed the heat exchanger, but if there’s a similar port you can connect it at the same time.
If you intake temps reach 70 C still, I’d try blowing the pump backwards with shop air to see if anything got back there and clogged the impeller If you can check pump flow, which is tougher and involves a lot more hose and time and a garage, I’d want to know if pump flow is getting up to 6-8 GPM (my guess here on what good flow should be). The return flow to the pump can be fed to a bucket, and another bucket supplying the pump suction (that pump is rated for 6’ lift, it’s meant for a boat live well) - and flow timed with a watch.
I’m almost 100% sure the CPS unit is air bubble free so I wonder if there is something else going on with my car? maybe the same thing that is causing the little bit of rough idle I’m experiencing after a hard driving day at the track?
Anyway, I am willing to further investigate the CPS issue though I wonder if it would be more cost/time effective to just have the system re-bled at a shop that does have a vacuum pump. If I do go that route I want to get so more logging done before so I can compare the after to see if IAT’s improved. I thinking 5 back-to-back runs from low 1st to the top of 3rd (better simulates a 1/4 run). What fields should I log other than IAT’s? If anyone has a better recommendation please let me know…
These are amazing times!!! :o Congrats!!
All I can say is how the hell are they still running in Ontario where it actually gets cold when here in BC its still 10+ degrees out and our season ended over a month ago!!! :
Jealous!
you guys got scammed
supposed to be 14 here this weekend, but I am not sure if the track is open or not. Would like to see boraVR6 take his new blue beast down there before next spring.
i pick up the car tomorrow morning sometime and sunday i have armistice at 11 am.
Kind of eats up both days there 
- i need to pick up some drag radials ;D I want to make sure most of the power makes it to the ground LOL
Drag radials ftl
You know i agree with you on this! But no street tire will survive a few runs at the track :-\
I just want to put a bit more meat in the rear to get a good grip.
Update - dropped the car off this morning to remove the O2 spacers and test the CPS unit. Talking to the shop owner he thinks it maybe an issue of the coolant mix. When John from Roc-Euro did the install he put straight Motul coolant and didn’t follow the mix recommendations (50/50). Mark (shop owner) thinks the straight Motul concentrated formula may not be allowing proper heat transfer resulting in the lack-luster performance.
Any opinions are appreciated?
Edit: well Arin confirmed it’s supposed to be a 50/50 mix! Hopefully that is the fix… Will see…
Bear, I just reviewed the instructions and didn’t see a recomendation from APR but since you talked to Arin it looks like 50/50ish… I believe that is what my delaer did when they installed… It’s definetly not straight coolant… I also used dionized water a few times to top off and coolant once or twice… Good luck and hope you get it ironed out…
^^Thanks PT
Yeah I PM’ed Arin and he confirmed 50/50 so I replied and suggested they add that to the install instructions as I am running 100% coolant. In John’s defense they do send 4 containers (5L) which is more than enough to fill the entire unit with straight coolant.
Bear that is guaranteed to be the cause. Straight EG or PG is not really suitable for heat transfer (or pumping in general)…usually people have to trim impellers to pump either one straight. I would only run enough EG or PG for your expected lowest temperature…and in the summer, I would run all water with a bit of water wetter. On my bikes I would never have coolant inside.
Yet another reason to look forward to spring.
poor CPS…keeps getting blamed for everything lol
first it was air, now it is the mix
Who is john at roc euro? Aren’t all Audis supposed to be 50/50 using G12? What made him think 100% would work…just a hunch with a customer’s car? Awesome!
Well technically this coolant doesn’t see any Audi parts - only Eaton, Jabsco, and APR - so you don’t have to run G12 - but don’t mix other coolants in there until all the G12 is flushed out.
John seemed like a good guy on the phone, and his “hot air intake” is on the fastest S4s right now…so I forgive him.
who is john??? the guy from strat? He’s a bit loony.
fastest B8 S4s on our list
primetime…custom intake. When he had a strat intake he dyno’d worse.
81bear…strat intake
imola monster…APR intake
kavan…??? intake
jspazz…no intake mod
asm77…no intake mod
fonzie…no intake mod
rynurz went low 12s with a strat intake as well
Seems the strat intake is more of a coincidence than anything else.
John@RocEuro = John@Stratmosphere
Yeah on the phone John said he had completed a few CPS installs and quoted 2-3hrs. I had a good experience with him on my exhaust and intake purchase so decided to let him do the install. Since it’s about a 4hr drive it had to happen during the weekend. After about 2hrs of the install it was clear that he had never done a CPS unit install before. From that point I stayed in the garage to watch exactly what he was doing. The total install time took 7hrs (ugh) but seemed to run okay and he definitely took extra care to ensure all the piping and connections were secure and zip-tied out of the way. Regarding the mix, I don’t think he was sure whether to mix or put straight coolant as there was nothing in the instructions that covered it and being a weekend APR was closed. They did send 5L’s of the stuff so I guess he thought it required straight coolant, why else would they send so much if you only need 1/3?
Anyway, I just hope this improves the the cooling of the S/C and increase it’s lifespan, not really expecting much in performance gain.
Just to keep it on topic, g12 it seems is used in some applications to even 10%, but this will only protect you to -4C (25F) or so. But to keep some corrosion inhibitor inside you’d want ‘some’. If you were very serious about the last 0.01 I’d consider using less than 50:50 in the summer.
Not sure if this qualifies for Saki’s mantra about running at the track the same way you run on the street, I’d imagine he’d lump this in with race gas and lowering tire pressures and removing the spare.
quit being a little bitch!
saki doesn’t give a fuck what you do to run your favourite time. It just goes in the notes if you’re doing something out of the ordinary…i.e. pulling your seats, running race gas, etc.
Just don’t compare your time when your car has no interior and no front bumper etc to someone who does and say ‘I’m faster!’
The point of the database and my philosohphy behind it is that it is a reference. If running watered down coolant, contrary to Audi and APR’s recommendation, makes you a hair quicker, all the power to you. Just make note of it, and I will make note on your time in the database. Same for race gas.
I don’t care about what a car does on race fuel or gutted interior, but the list isn’t for what I want to do to my car. If it was it would only be RS4s, on pump gas since that’s all I drive. No, the list is for everyone to compare their various mods/ideas/setups to one another. If you haven’t noticed, all I’ve asked is that you run at a certified track, and provide some evidence to support your time. I’ve included every time that qualifies with that very simple rule. There’s a car on the list that ran with 900 lbs gutted out of the interior. NINE HUNDRED POUNDS. It was noted in the miscellaneous info section, and added to the list. Done.
I don’t know why you take this so personally like I’m organizing religious persecution. It’s a fucking dragstrip database.
Saki, I think it was more of a jab at you (in good fun) than anything else…
I don’t see running a watered down coolant mix providing much of a benefit in performance during a 1/4 mile run so I wouldn’t even note it.
However, I totally agree with you Saki the more info the better. As I said earlier I don’t see it making much of a difference performance wise but I have absolutely no problem having it included. I believe Mark is going with a 50/50 mix but will ask him when I pick the car up.