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Discussion Starter #1 (Edited)
Final update 09/05/15: myth busted (IMHO). A 20* drop in surface temperatures at the base of the supercharger appears to have no tangible effects in lowering IAT2 (see post #3)

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Background:
Per the manufacturer:
With the Thermal reduction plates the blower will operate significantly cooler and make it perform as if were in cooler weather consistently... Higher Case temps create higher IATs, Higher IATs reduce spark advance and lead to spark Knock
The CTS-V temperatures recorded were 125-185 Deg F and they were reduced 25-50 deg F... Smokey Yuniks rule of thumb was there is a 1% gain of power for every 10 degrees of lower air temperatures. You are therefore looking at a 3-5% power gain. If you are making around 570rwhp that is a 18-28.5 rwhp gain
Ideally, I will be able to confirm results similar to those claimed, as I have a daily driver that sees stop-n-go traffic mixed with 25+ miles of interstate driving and I often see IAT2s creep up while waiting to enjoy that next on-ramp.

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Methods:
The test Circuit is 13.3 total miles. Cold start in AM, normal driving (little to no boost) to RB Road, allowing for full warm-up. 3rd gear pull from 2500 RPM to 6400 RPM (~35-100mph), then normal driving to interstate for another ~3miles of driving at 70mph. Logging will end at that point.

How I routed my intercooler system: BMR reservoir + removal of factory hard lines in the following fashion (I already have a Track Attack heat exchanger, ZL1 lid and Varimax pump):



Remember that I am also using 50/50 dexcool with 1/2 bottle of water wetter. Those of you running only distilled water or water with Water Wetter will likely experience lower IAT2's and possibly faster recovery times under similar situations. Also, the routing of my coolant system may potentially skew my findings, but that is also debatable!

The vendor states they have IAT2 data for the larger spacers, which I have not yet seen publicly posted. If anyone has a link to their testing, I would love to compare my methodology to theirs.

I am using the thinner 3/16" phenolic spacers (with mylar cover) designed to fit under a stock hood, which will likely contribute to less than ideal heat management. The vendor states that you will have to lower the cradle to use these if you also have a ZL1 lid - however I did not need to do this (my lid is milled), and installation was relatively straight forward.

** I Recommend you replace your blower-to-cylinder head bolts after every S/C removal! We managed to snap one after the second blower swap...

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Time for data (aka RESULTS):

ETA: Updated 08/31/2015:
I plotted a baseline run with my BMR reservoir tank from last month vs a run today: each run was made on the same route I've used for all of my cooling system testing, with each run occurring roughly 10 minutes in from cold-start (the car is warmed up at this point; ECT's hit 190 within 4 minutes of cold-start on all runs). The baseline / first run's ambient tempurature was 80* as read on the NAV screen, the comparison run this morning with spacers had an advantage with lower ambient temps of 75*:


IAT2 Cruising temperatures were not plotted (sorry, Evil_V); however my data shows no improvement in steady-state highway cruising @ 70mph vs previous baselines: With the BMR reservoir alone and with the reservoir with Phenolic spacers, I record 16-17* over ambient temperature in 75+ degree weather. I did notice a 1-3* drop in IAT2 when I added the BMR reservoir and 3/4" lines over stock lines and orientation under similar conditions.

ETA 09/01/2015: Second comparison based on ambient temps and starting IAT2:


** Higher or lower cruising speeds, even resulting in a few hundred RPM difference, will cause equally variable IAT2 in my experience. The conditions and environment in which you choose to test will greatly influence your outcomes! I do also have IAT1 data but don't use it due to the tendency of the MAF sensor to heat soak and skew data.

Commentary:
Preliminary data is rather suggestive in that the spacers seem to actually be trapping heat in the blower during WOT pulls, as some have feared (Comparison 1). This makes sense since the bulk of heat production is from the blower (and not the cylinder heads) in that scenario. Engine coolant temps reach 190+ in my vehicle typically within four minutes of driving (70+ ambient); this may explain why the blower appears to already be heat-soaked at the beginning the first data set in spite of lower ambient temperatures. With ambient conditions of approximately 80*F with ~10 minute warm ups and back-road driving averaging around 40mph, IMHO this should have been the ideal scenario for these spacers to shine (clearly, they did not).

Comparison 2 shows identical IAT1 and IAT2 starting conditions, although ambient was marginally cooler by 3*F in the baseline and that was reflected in the driving warm-up IAT readings early on. Here, IAT2 essentially mirrors itself in either run - thankfully showing no "heat soak" but remember that ambiet baseline run is ~10 degrees cooler in this comparison, again with very short drive times prior to the runs!

As for dyno runs and heat soak - that may be a different issue; but we all know glory runs on the dyno are kryptonite for being taken seriously around here.

Disclaimer:
* PSA: This is my own data - your mileage may vary. Every attempt at unbiased comparison has been made as best I can do it, afford it, and plan it out. If you don't like it, no problem. If you did your own testing, and had fantastic results - please share! If you want to degrade my efforts because your "horse" didn't come out on top, then go fuck yourself.
* IAT2 is NOT the same thing as blower casing or lid surface temperatures!
* More runs will be completed over the next few weeks to rule out anomalous data points, and for averaging to account for changing temps.
* These are two single WOT-run comparisons baseline ambient was 80* vs the spacers run with 75* ambient. Again, same route was taken in each case, with each run roughly at the 10 minute mark from my datalogs. If this trend holds up, it appears as though there will be no benefit from the phenolic spacers if full heat soak of the blower occurs within 10 minutes of engine warm up.
* see post #3 for a detailed IAT2 comparison of two driving logs for my final, definitive comparison.
 

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Discussion Starter #2 (Edited)
COLD START TEMPERATURE COMPARISON:
* Baseline is ZL1 lid, Track Attack and Varimax pump with factory hard lines and routing.
* Comparison is Phenolic Spacers with reservoir tank, 3/4" line and hard lines removed (not a straight comparison as with the above WOT data).
* This was at idle only.


Note: the dip in the graph around the 5-6 minute mark is from the radiator fans kicking on.

At key-off, heat readings from the engine bay with a pyrometer were:
07/24/15 Baseline: ECT = 197*F, S/C Base = 182*F, ZL1 Lid = 141*F
09/02/15 Spacers: ECT = 196*F, S/C Base = 163*F, ZL1 Lid = 146*F

Discussion:
So there's your 20* difference in "supercharger temperatures," as measured near the cylinder heads! Again, supercharger temps != IAT2. Secondly, notice that consistency, Chris! Spacers may indeed slow the heat transfer as claimed, but my post below reveals that this appears to have NO bearing on realized IAT2.

Basically, with zero heat from the supercharger, one should expect ~7* F difference at idle over 25 minutes in mid-70* weather. The FanBoys and drag racers will focus on this one specific graph to support their feeling of benefit. Perhaps that's true: There may be more consistent temperatures while staging, however that consistency is NOT the same as actually getting lower temperatures. In other words, the temperature delta only appears if the supercharger is not spinning fast enough to create heat - which is hard to do anywhere except while idling for 20+ minutes.

I suspect that after a 1/4 mile run, sitting in the lanes waiting for your turn - IAT2 temps may in fact be more consistent (not necessarily lower, but who knows!). Hopefully the drag racers can post similar data from their runs to help clarify this disparity.

Again, note that Supercharger case temperatures do NOT equate to an equal drop in IAT2.
 

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Discussion Starter #3 (Edited)
Okay, here are two highly similar data logs and 3rd gear pulls for comparison.

Both plots are from a cold-start in the AM on my way to work, 08/24/15 vs 09/03/15. This course has 2 stop lights and I drive ~45-50mph prior to the 3rd gear pulls due to traffic. Ambient conditions were pretty damn close, as well as the length of each run and the start of the 3rd gear pulls in each run. No extended idling at stop lights, etc and exactly the same course:



** Note that the beginning temps vary due to my parking in the garage - which traps heat from the day before and skews the "key on" temps. Sorry if you feel that is a disqualifier; I think the graph pretty much speaks for itself.

ETA 09/04/15:
Full IAT2 data from the two most similar data logs I have. Baseline (control) is 69*F and with the Spacers it's 71*F. I will add in reference points to the logs (two stop lights, one stop sign, and entering onramp / highway) - but it's immaterial.

Again, both runs are fresh starts in the morning, sunny / clear. IAT2 graphed specifically, but IAT1 and ECT, MPH all match up pretty damn well.


Note: IAT2 vs ambient at 70mph highway speeds, approximately 6 minutes after the 3rd gear pull were essentially identical at 18-19* over ambient.

Unless you are idling for extended (20+ minutes) periods, my personal experience and data logging reveals that this myth is busted: the spacers DO lower supercharger temperatures at the base (only - lid temps are unchanged), but do NOT lower IAT2 in any detectable way while driving, highway cruising or WOT conditions in my testing.
 

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In for updates!

I'm getting my car tuned at the end of august by Jeremy and wanted to buy these spacers as well.. Are you going to be running these with a ZL1 Lid by any chance ? Curious on whats needed for this to work if so.
 

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Discussion Starter #6

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Placeholder for future comments about headers vs manifolds
 

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Discussion Starter #10
I am soooo going to have to start a new thread...
 

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Note - I won't able to afford the install until I receive profit sharing from our joint air foil venture.... :D
Yours are going out this afternoon with some vinyl as requested. Let's make sure they fit first, then we can talk about your contribution to the effort. LOL And I don't want to hear 'does it look better here or here?'. 'A or B' 'B or C'. Isn't that what you say all day long?
 

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space saved for future comment lol
 

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In for results
 

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Discussion Starter #15 (Edited)
is this really a thread about starting a thread at a later date?
Fuck yes.

A: I'm writing shit down, so in case I lose my notebook, or my computer crashes I'm not totally lost on the $400 spacers, $400 labor/dyno, and about a month's worth of time and note-taking.

B: Sometimes people provide good feedback, like doing a single 3rd gear pull vs 0-100, etc.

C: Just to give cunts like yourself something to get snarky over, because I know you need that release.

D: For the fuck of it.

E: ETA - and it totally legitimizes the thread, because the "before" info is there well in advance of the "after" info. Of course, I'll have datalogs to prove it anyway... but still.

F: Saved for future gofundme campaign.

G: Thread-save:


I suspect the spacers will delay heat transfer on the run but possibly extend the IAT2 recovery time... Maybe I'll try to do two pulls back to back and see what happens. Might be tough to do and stay out of jail though...
 

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Discussion Starter #18
I think I'm wasting bandwidth, Gimme a sec to delete stuff - but I'll leave the bouncy boobies.

Sent from my SCH-I545 using Tapatalk
 

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Fuck yes.

G: Thread-save:
I had to scroll her out of the picture just so I could concentrate long enough to read what you wrote, but after seeing her it became less important lol
 

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Discussion Starter #20
I just wanted to add: I've been measuring the supercharger lid, base and cylinder heads after each logging session.

The ZL1 lid literally will cool off from 120+ degrees to 90 or less in approximately 1 minute, as measured with an infrared thermometer pointed at the fitting block. Wild...

Also, the supercharger base adjacent to the intake ports trends around 160-170 degrees, with snout being 30-40 degrees cooler, when cylinder heads are hot @ 196 degrees.
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