'14 AGM 1SS/1LE Track build [COTW 11/17/14]

[four0nefive]

Hey X25,

Awesome build thread! Also noticed you were from Washington. Quick question, are you tracking your car at Pacific Raceways on the 20th or somewhere else. Thanks in advance!

[X25]

Originally Posted by four0nefive

Hey X25,

Awesome build thread! Also noticed you were from Washington. Quick question, are you tracking your car at Pacific Raceways on the 20th or somewhere else. Thanks in advance!

Thanks, where are you in Washington? Once I hit below 1:38s years ago, it started becoming very hairy at Pacific Raceways since it's a very hazardous track. I don't think I've been to that track since 2013. The track day on 20th is at The Ridge Motorsports Park in Shelton, WA. Since it's still considered winter time, it will be $195 for the whole day. Here's hoping the weather holds up!

[four0nefive]

Originally Posted by X25

Thanks, where are you in Washington? Once I hit below 1:38s years ago, it started becoming very hairy at Pacific Raceways since it's a very hazardous track. I don't think I've been to that track since 2013. The track day on 20th is at The Ridge Motorsports Park in Shelton, WA. Since it's still considered winter time, it will be $195 for the whole day. Here's hoping the weather holds up!

I'm in Renton. I'll check out Ridge Motorsports Park, didn't know that track even existed! I wasn't going to participate in the track day, but I was interested in doing some photography of the track day.

[X25]

I just bought my spot yesterday, and finally will attend the first track day of the season this Saturday! I will be going to the Ridge Motorsports Park. Last time I was there (excluding the foggy day), I had Trofeo Rs on, and made 1:56.56.

The differences this time:

• Better race harness + harness bar
• Eaton diff
• MPSC 2 tires (305/30/19; older non-Porsche spec)
• Track surface might not be in the best condition (hard rains lately; might also be too cold)

What do you guys think about thermostat change? I remember Stephen12ZL1 posting the pic of the Z/28 OEM thermostat, and it had a marking for 160 degrees F. It also looks like the engine enjoys much better advance timing with lower temps.

From another thread:

Originally Posted by jwithers2005

I have to disagree. heres why...

I just installed TSP full exhaust and CAI on my L99 Camaro..i literally just got home from the dyno from having it retuned for the new parts. the first pull after the initial tuning yielded 362.2 hp with the car at normal temp operating range. the dyno session sheet says temp was 191 @ the beginning of the pull, and 194 at the end...with the fans blowing on it for a few minutes, it cooled to 178 at the start of the pull and was up to 180 by the end ..the tune was not modified at all and the car made 368.8hp on the cooler run...the 3rd pull back around the 190 mark was again down in the lower 360 range...

.....

I looked it up, and Z/28 thermostat is just $25:
http://www.iamgmparts.com/chevrolet/...ame=thermostat

In short, I am wondering:

1. Is it good to run a cooler thermostat for this engine? Would it make a difference at the track?
2. Is it OK for street use as well?
3. Are there better aftermarket thermostats (like high flow versions), or are they all the same?

Here is the UNCUT version of one of my last track days from last summer. As you can see from the gauge, the coolant temps sometimes hit as much as 220 degrees; way more than 190 target (of OEM thermostat), despite having the DeWitt radiator:

[White_SS/RS]

That's a good question. The entire system was designed to maintain a ~200 water temp. What usually happens with lower temp thermostat is that the engine will only run at those lower temps during mild street use and at low ambient temps. This is mostly due to the fans being inoperable at the lower temp. To remedy this you would need to modify the fans circuit since the ECM only allows the fans to be programed to 190 or 195 if I recall correctly. Otherwise the engine will just run at the temp its designed for and the thermostat remains in a continuous open cycle. I'm sure if the cooling capacity or efficiency of the system is increased as well as modifying the fan circuit you would see benefits from it.

I'm curious though if there is enough airflow to offset the amount of heat generation during track use to push the temps lower than what is normally seen ~220. That would be assuming you started with a lower temp in the first place. Its my guess that it would just stay where it normally nulls out in the ~220 range. I mean, the system already displays its incapacity to maintain the 200 let alone bring it below that.

[X25]

Originally Posted by White_SS/RS

That's a good question. The entire system was designed to maintain a ~200 water temp. What usually happens with lower temp thermostat is that the engine will only run at those lower temps during mild street use and at low ambient temps. This is mostly due to the fans being inoperable at the lower temp. To remedy this you would need to modify the fans circuit since the ECM only allows the fans to be programed to 190 or 195 if I recall correctly. Otherwise the engine will just run at the temp its designed for and the thermostat remains in a continuous open cycle. I'm sure if the cooling capacity or efficiency of the system is increased as well as modifying the fan circuit you would see benefits from it. I'm curious though if there is enough airflow to offset the amount of heat during track use to push the temps lower than what is normally seen ~220. that would be assuming that you started with a lower temp in the first place. otherwise its my guess it would just stay where it normally nulls out.

In my experience with the Miata, lower temp thermostat not only has dropped the starting temps to the track sessions, but it has also allowed higher flow due to being more open at high temps. I actually overpaid for a Cosworth thermostat, which claimed it 'opens up better'. I am not a tuner, but dropping the coolant average temps by 20 might have a profound impact on the ignition timing, and the actual HP we get.

[Burt]

Running a lower temp thermostat seems like it would slow down the process of heat soaking, since it opens earlier, and concerning whether the Z/28 thermostat is a good idea on non-Z/28s, I remember reading an article in which Oppenheiser or one of the other main Camaro guys said that they made the thermostat to be an affordable upgrade for lower spec cars.

[White_SS/RS]

Originally Posted by X25

In my experience with the Miata, lower temp thermostat not only has dropped the starting temps to the track sessions, but it has also allowed higher flow due to being more open at high temps. I actually overpaid for a Cosworth thermostat, which claimed it 'opens up better'. I am not a tuner, but dropping the coolant average temps by 20 might have a profound impact on the ignition timing, and the actual HP we get.

Absolutely would be a benefit to timing. You may have something with the thermostat being further open when its well above its normal operating temp. Pretty cheap to do. Give it a try and see what happens. I've had good experience with Mr. Gasket brand of thermostats. not sure if their LS offerings are as good as their older ones.

[X25]

Originally Posted by Burt

Running a lower temp thermostat seems like it would slow down the process of heat soaking, since it opens earlier, and concerning whether the Z/28 thermostat is a good idea on non-Z/28s, I remember reading an article in which Oppenheiser or one of the other main Camaro guys said that they made the thermostat to be an affordable upgrade for lower spec cars.

Sounds great. If it works similar to what I had with the Miata, I'd imagine I'd hit close to 160-170 degrees only on the highway low RPM cruises. I'm not sure if the engine would throw a code for that, though. I asked about the thermostat to Matt @ FSP as well (since I'm running his mail-order-tune), but he's historically been very slow to respond, if he responds AT ALL.

[clarkkent]

Awesome, I love watching those track vidoes

[X25]

Originally Posted by White_SS/RS

Absolutely would be a benefit to timing. You may have something with the thermostat being further open when its well above its normal operating temp. Pretty cheap to do. Give it a try and see what happens. I've had good experience with Mr. Gasket brand of thermostats. not sure if their LS offerings are as good as their older ones.

OK I'm going to order one, and install it before the next track day (after this Saturday's). Looking forward to seeing what happens! I'll just get the OEM Z/28..

Originally Posted by clarkkent

Awesome, I love watching those track vidoes

And I love making videos with data overlays! I just ordered one of those 2-in-1 Windows Laptops with a sixth gen i7. I'll try and see if I can make my videos on it, without having to sit down in front of my desktop. It also looks very nice!

[X25]

Just ordered the Z/28 (160 degrees F) thermostat. I'll compare it with the stock unit once I get to install it, though we'll most likely not see any visual difference.

[Stephen12ZL1]

a lower temp thermostat is a "no brainer" mod. Honestly, it really can't hurt & might help. If GM decides to use one in a stock LS7 (confirmed), there must be merit to this "mod". The worry warts here will cry foul so just ignore them.

[Dropspeed]

Originally Posted by Stephen12ZL1

a lower temp thermostat is a "no brainer" mod. Honestly, it really can't hurt & might help. If GM decides to use one in a stock LS7 (confirmed), there must be merit to this "mod". The worry warts here will cry foul so just ignore them.

LS3 and LS7 are two different motors, simply stating if GM decide to use it there must be merit holds no weight as they are very different. Simple things like fan switch, oil capacity, cooling system and that pesky calibration thing are all different and part of how the correct operating temp is controlled

My suggestion is make changes to the coolant system and you will see the best results. (T-stat, radiator, fan switch, cal)