EPL stage 1 on Q5 - cooling question

[BierJager]

I finally decided to go Stage1 EPL and hope to be downloading the tune in the next day or so. I understand the SQ5 has additional cooling over the Q5 and I'm wondering specifically what are the differences? While I won't be thrashing this thing daily, I would still like to know what's involved in increasing the cooling capabilities of the car. What if anything would you recommend doing to a standard Q5 if running stage1? Do people sell the SQ5 cooling components when they upgrade for stage 2 or 3 or is the aftermarket a better way to go from the start for these parts? TIA.

[riceboy22]

There's an additional radiator on the SQ5, but the amount of extra cooling that provides relative to the power you're adding is probably minimal. I don't think I've seen anyone retrofit the SQ5 cooling components to a Q5. You should be fine on stock cooling with stage 1 if you're not trying to track it and don't live with 100+ ambient temps. Here's a diagram stolen from AW:



It would be prudent to do some logging before-and-after and monitor things like IAT, timing, etc after you flash to stage 1.

[MSq5]

You will probably be fine with EPL Stage 1 on stock cooling, unless you are in a very hot climate.

FWIW, I am running a Q5 3.0T with EPL Stage 2. My oversize crank pulley is relatively small, 179mm, so my experience may not apply to those running higher ratios.

I had no problem with cooling on Stage 1 tune and jumped to Stage 2. The only time I am seeing any drop off in power is if I try to do two WOT pulls back-to-back without giving it time to recover. Just driving on the highway a few minutes seems to bring IATs back down fairly quickly.

I did not do before and after IAT logging when on Stage 1, so I can't be more specific.

I do plan to upgrade cooling, probably with APR's CPS. Probably do that sometime over the next few months. That's probably as far as I'll go as my needs are modest. I'm not trying to be the quickest Q5. I will not be regularly running the car at the dragstrip or running hot laps on a road course. I just want a nice bump up in power while staying reliable. The main reason for considering the CPS is that I am in the Deep South and it does get over 95 degrees F. regularly in summer, sometimes over 100 F.

[jomama229]

if you're gonna invest the time and labor to upgrade cooling, you may as well drop in a larger aftermarket one, even if it costs you more in parts.

if you insist on retrofitting the SQ5 cooling, just punch in the part number from riceboy's screenshot and you'll find vendors that sell the radiator. i think fcpeuro has an oem one for $218.

i'm epl stage 1 and while the car does get heat soaked from time to time, it runs fine on stock cooling 95% of the time. if you plan on going stage 2 and want to get ahead of the cooling game, then sure, by all means, upgrade now.

[BierJager]

OK this is exactly what I wanted to know. Thanks for the part numbers and specifics on the differences.
Michigan only had a few days in the 90's last year and we're usually 70s' and 80's all summer so I think I'll be good. This car will never see a track. All I really wanted was the car at least as fast as an SQ5 for the usual needs like stoplights, two lane on-ramps that merge to one, and similar situations. I also just couldn't stand the fact that the motor was de-tuned so much from the factory.

[BlackSVT]

All I can say is try it with stock intercooler radiator and see how it does for you. Just acknowledge (even in silence, if only to yourself!), it's a slippery slope with mods...

That said, in the Chicago area, with my 3.0T at Stage 1, I could definitely notice pullback in the Summer with 93 octane, but didn't put much effort into measuring IATs, timing pull, etc. It's definitely my daily driver and with it getting used to the tune of ~350-450 miles/week, i just dealt with it. Then about a year ago, I went Stage 2, and started to get more picky... lasting thru Summer of 17 without cooling upgrade, but it bugged the hell out of me the whole Summer. The car just felt slow at anything above 70F. I just recently installed APR's CPS radiator, and I have to say it's been a really nice upgrade so far! I hit it pretty hard this past weekend when it got a bit over 70, and the car remained strong the whole time. I could get P3-reported IATs on a long full-throttle pull to briefly touch in the 110-115F (~45C) range, but they came down almost immediately back to ~85F range. ....now what else am I gonna change...Hmm.....

[BierJager]

All I can say is try it with stock intercooler radiator and see how it does for you. Just acknowledge (even in silence, if only to yourself!), it's a slippery slope with mods...

That said, in the Chicago area, with my 3.0T at Stage 1, I could definitely notice pullback in the Summer with 93 octane, but didn't put much effort into measuring IATs, timing pull, etc. It's definitely my daily driver and with it getting used to the tune of ~350-450 miles/week, i just dealt with it. Then about a year ago, I went Stage 2, and started to get more picky... lasting thru Summer of 17 without cooling upgrade, but it bugged the hell out of me the whole Summer. The car just felt slow at anything above 70F. I just recently installed APR's CPS radiator, and I have to say it's been a really nice upgrade so far! I hit it pretty hard this past weekend when it got a bit over 70, and the car remained strong the whole time. I could get P3-reported IATs on a long full-throttle pull to briefly touch in the 110-115F (~45C) range, but they came down almost immediately back to ~85F range. ....now what else am I gonna change...Hmm.....

Yeah I know...dang it. If this were my personal ride, it would be worse. It's the wife's car and she doesn't even want this stage1 but I think once she has some time behind the wheel with it, she will like it. Thanks for your feedback.

[riceboy22]

All I can say is try it with stock intercooler radiator and see how it does for you. Just acknowledge (even in silence, if only to yourself!), it's a slippery slope with mods...

That said, in the Chicago area, with my 3.0T at Stage 1, I could definitely notice pullback in the Summer with 93 octane, but didn't put much effort into measuring IATs, timing pull, etc. It's definitely my daily driver and with it getting used to the tune of ~350-450 miles/week, i just dealt with it. Then about a year ago, I went Stage 2, and started to get more picky... lasting thru Summer of 17 without cooling upgrade, but it bugged the hell out of me the whole Summer. The car just felt slow at anything above 70F. I just recently installed APR's CPS radiator, and I have to say it's been a really nice upgrade so far! I hit it pretty hard this past weekend when it got a bit over 70, and the car remained strong the whole time. I could get P3-reported IATs on a long full-throttle pull to briefly touch in the 110-115F (~45C) range, but they came down almost immediately back to ~85F range. ....now what else am I gonna change...Hmm.....

If (when!) you go beyond Stage 2, you'll find that even with the CPS IATs can get pretty crazy. I was seeing peak up around 75C when doing some longer 3-4 runs in about 80F ambient temps. I've actually considered reducing the pulley ratio a bit, but the mid-range that I use most frequently is so much fun DP at 3.238.

Yeah I know...dang it. If this were my personal ride, it would be worse. It's the wife's car and she doesn't even want this stage1 but I think once she has some time behind the wheel with it, she will like it. Thanks for your feedback.

I would still recommend finding someone who can take some logs with you after tuning if you don't have the tools for it yourself. It will give you peace of mind knowing that things are running properly. Here's a good guide: How To: VCDS Performance Logging.

[Chris@EPL]

Stage 1 cooling with a properly maintained car will not be a problem. That being said a cooling upgrade is always worth while. But the money and time to swap in the SQ5 cooler is not worth it over a good quality cooling upgrade.

[drivenagain]

I have a pretty aggressive DP setup, the car can live on no cooling mods, it is NOT the best as you will get maybe one full pull before the ECU says nooooo