Ecotec single pass to dual pass

[silver]

[quote="DarthChicken"]
Sorry silver, what you are saying doesn't mak sense.  Take kitchen knife, and heat it over a burner.  Lay it on a small piece of ice, and hold
still on that ice until the small piece of ice is gone and turns to water.  Now take that knife and touch your tongue.

Now take the knife, heat it up, and slide it across multiple pieces of ice.  I'm betting the knife cools off before the ice melts all the way.  Just because the larger qty of ice hasn't melted doesnt mean it's not absorbing heat.  It's just spread out over more ice.

Also - the idea of using a larger resevoir has the same affect.  More liquid to absorb the heat.

What our cars need is better laminovas with more surface area

edit:  ok, I see what's going on - this is a misunderstanding on what the stock piece does.  The stock piece recirculates water
through four time.  What max has done is make it so it only goes through twice.  And... Single pass can be done
for even more improvement. 
[/quote]

darth can you make a pic or diagram of what a single pass would be?  I'm trying to understand how that would be hooked up?

[Gage]

[quote="silver"]
I think my ebay intercooler behind the seats is what's really NOT helping my system, no air flow, and not a quality core so it's cooling properties are probably below spec.
[/quote]

And yet you appear to have eliminated heat soak in non track conditions.  So, what is the problem?  Or are you simply saying that things could be better with a better heat exchanger?     

[DarthChicken]

https://www.zzperformance.com/cobalt_ion/products1.php?id=1163&catid=188

http://www.cobaltss.net/forums/showthread.php?t=199783

[silver]

ok that makes more sense...you'd have to modify the whole thing to make it work, I gotcha now.


Gage, well initially I drove my car at around 70 degree ambient temps and at that temp, everything is fine, it gets down to 120 so not a problem BUT, now that it's 100 outside it won't go below 140, and easily shoots up to 160 without much effort..............so basically if you live in areas like Texas, heatsoak is much much more of a problem then if you live in the northeast.



I was told that my ebay intercooler which was truly cheap, would potentially not help at all due to having cheap cores and a low end design...I don't understand intercooler technology enough to debate it so I accept the criticism, I'm hoping that the new intercooler that I purchased which seems to be a much higher grade part built for a GM suburban magnusson supercharger, that it will operate better.................I'll remove the factory oil cooler heat exhanger up front, replace it with the magnusson intercooler, which will have 2 fans on it, if that doesn't help enough, then I can remove the rear intercooler and have a reservoir welded up that will fit in the exact same spot so the plumbing and mounting is already done, this would add 3.75 gallons to my current system's volume.  I think currently the system holds less than 1 gallon, so what everybody agrees on is if you can increase the capacity of the system then it takes much more to heat up ALL the liquid, which would reduce your IAT2s considerably.

[Mr.Woolery]

What kind of AIT1-->AIT2 temp deltas are you guys seeing? 

Another data point:  Over the last few years, I've noticed average deltas of between 40-50 degrees between AIT1 an AIT2, and AIT2 temp ranges between 100-145 degree regardless of the ambient temps (even really hot days).  I've never seen AIT2's higher than low 150's in my Atom under any condition.  I'm also still running the original GM tune (the one that's widely considered too rich).

[silver]

I'm seeing 70 degrees upon acceleration

IAT1 at 100 IAT2 at 170

I've seen as much as 82 degrees when it was IAT1 at 86 and IAT2 hit 168


what's important is to know that Cobalt owners who've done extensive research and changes to the system have achieved deltas of 20 degrees, to which, they don't get over 110 IAT2 ever, that should be our goal is to achieve a HIGH of under 120 on IAT2 regardless of driving conditions................unfortunately I don't think it's possible unless you go turbo, OR run METH.

several owners running meth report IAT2 below IAT1, so obviously that's a ridiculous change from what we are used to.



If you live in a cool climate then 50 degree delta isn't such a big deal b/c with IAT1 between 60 and 70 for most of the year you're seeing IAT2's between 110 and 120 and at those temps you're not losing power to heat soak, but in Texas and other hot climates the 50 degree delta needs to be reduced to 20 degrees.

[Speedytec]

[quote="silver"]

so.............we are in a consensus that a large resevoir that's INLINE would be a great addition?

I think my ebay intercooler behind the seats is what's really NOT helping my system, no air flow, and not a quality core so it's cooling properties are probably below spec.
[/quote]

Large in-line reservoir will slow down a possible heat soak, but then it also slows down the cooling of your warmed-up coolant.
Such large reservoirs are good for 1/4 mile passes where you can cool things down between passes. (they even put icewater in...)
Not so helpful for track use. => you need an efficient radiator to spill the heat quickly...

Edit: you should stick a temp probe in the coolant line (to your cores) to see if your radiator(s) can spill enough heat. (PC watercooler probe => http://www.watercoolingshop.co.uk/Green ... AQF8G.aspx)

[Gage]

Everyone is looking for a solution that doesn't have a ridiculous price tag.   

[silver]

[quote="Gage"]
Everyone is looking for a solution that doesn't have a ridiculous price tag.     :pop:
[/quote]

even with a ridiculous price tag we're not getting anywhere.

Not one person has posted before and after temps with Tom's $2200 intercooler.
Nobody's posted IAT2's with meth versus without..all other factors remaining the same.

I already spent $2500 to upgrade my supercharger / air intake / tune and whatnot, which was supposedly going to reduce IAT2's 20 to 30 degrees...NOPE..............BUT at least I'm still getting over the 300hp that my car is supposed to.

so for me, I'm happy with the power, I'm concerned with high IAT2's because they are annoying but at least when they are hot I still have 50-75 more whp then before.

[Cptnrob]

Well I have results with my intercooler refit.  Silver and I have been talking back and forth about it quite a bit and his is at the shop now getting a refit too.  Thought I'd share.

Here's all I did from the stock Brammo setup:

Replaced pump with a high flow pump
Rewired pump to run off straight 12v when the engine is on.  Not controlled by ECU
Replaced oil cooler up front with the magnuson dual pass heat exchanger with 2x 7" fans behind it.  Some custom work was done to this to make it fit better in the Atom.
Custom fit 1.5 gallon inline coolant reservoir behind the seat

Car still has the old single pass end plate and nothing with the laminova tubes was changed.

IAT1 was 100 degress.  On repeated back to back dyno pulls the highest recorded IAT2 was 131.  No heat soak drop off at all, very consistent.

I went ahead and had them tune it as it was running really rich.  I had Shinoo's tune on there before.  After the tune I put down 251.9 HP on a safe tune.

I'll get some pictures later.  I kinda got caught in a downpour on the way home and did and oil change to be safe and other fun stuff.  I haven't put it all back together yet.

[Gage]

Thanks for sharing!

[Speedytec]

[quote="Cptnrob"]


Car still has the old single pass end plate and nothing with the laminova tubes was changed.


[/quote]

I still should change this to a dual pass, as that will cool the air better with this pre-rad set up. Especially when you fit a smaller pulley and the SC makes more hot air... 

[Cptnrob]

I just discovered that the 2 7" fans on the new heat exchanger aren't running and apparently they weren't running the when the dyno was done either I just learned.  So I had a high of 131 IAT2 after several dyno pulls with no fans.  The fans were hooked up using the same wires as the old one, but the old one ran all the time and these don't.  Is it not getting hot enough to make the fans come on?  What controls when the fan comes on?  There's more to shave off that IAT2 if I can get the fans going.

[silver]

it has to be since he wiped the tune and started from scratch that must have deleted the setting to turn the pump and fans on.

[Gage]

Was there a large fan blowing on the car during the dyno pulls?  (which is typical to simulayte driving conditions)