Lone Ranger

Been driving after putting in the 160 tstat and bypassing the throttle body coolant. To the guys that gave me advice on both jobs in other posts, I thank you. Now for what I've noticed. The coolant temp digital readout does show lower temps on average. Going down the road with good air flow (anything 30mph + without vehicle directly in front) and the coolant temp wants to stay around 185. This is with the fans programmed to come on at 211F and go off at 197F-- more on fan settings in a minute. The car feels about the same upon firt getting under way, but what I noticed is that the responsive feel doesn't seem to fade after the engine is up to operating temp and the engine compartment is heat soaked. Before when those conditions set in after about 20 minutes of driving in the summer swelter the car would feel slightly less responsive than it did the first 20 minutes or so, likely due to heat build up (?) I have to wonder if this apparent phenomenon is more attributable to the TB coolant bypass than the 160 tstat. BTW, I need to find a couple nice end caps for the coolant nipples on the TB, looks ugly as is. Okay, now for the fans. I have a Hypertech Power Programmer III, and was hoping the fan settings it offers would work well w/ the 160 tstat. Not so. It *should* be so based on what's printed in their manual, BUT what the programmer programs and what the manual says for the fan activation temp ranges are two different things! Manual says 160 settings are on/off = 192/185. Nope. I wish they were, that would be just about right. But the LCD readout during programming offers 160 settings of 176/165 on/off. WTH? When I tried that hoping the manual wa right and the LCD on the programmer was in error, I found out *neither* seems to be the case! Using Hypertech 160 fan settings they actually kick on at 185F and I haven't been able to determine the off temp because I got fed up sweating my **** off in the driveway today waiting for the fans to bring it down enough. Fans still on at 178 when I said f**k it and went inside and laid in the a/c underneath the ceiling fan. Tonight I went back at it and tried the programmers 180 tstat settings. The programmer's readout and the manual again disagree on settings, this time for 180: manual says 213/205 on/off, programmer readout during programming says 192/185 on/off. This time I was able to test it real life after programming for 180 fan settings and discovered: 211/197 on/off :crazy: Okay, I'm confused now, thanks Hypertech. But, I drove around using the 180 settings and found it to be acceptable, although I'd rather see a range of something like 205/196 on/off. Have to wonder if there's a way to hack the bin file in the Hypertech and insert one's own fan temp activation settings using a PC link and some sort of edit software...(?)




[Modified by Lone Ranger, 11:20 PM 7/27/2002]

gtsyellow

how again did the engine fan effect you sweating? i have mine comming on at 185 and a 160 therm, car stays about 170deg in normal running situations & works lovely. i'm just confused how fan temp effected your personal well being

NE14SIN

I think what he was saying was that he was outside in the car without the a/c on and the heat..from the sun made it hot outside. Did you not understand that part, or did i miss read it?

Lone Ranger

Actually I meant that outside in full sun midday heat index over 100 standing over the car w/ hood open and heat blooming up off the engine I got tired of messing with it and went inside, stuck my head under the faucet a minute and took it easy for a while! :D

KurtK

This may be an ignorant question...did you try to see if the reprogrammed fan trigger temps worked with the A/C on?

I believe the PCM uses 2 different temp settings, depending if the A/C is on or not.

Also- does the A/C system have a full charge of refrigerant?

Lone Ranger

Turning on the a/c kicks the fans immediately into high speed mode. and so they stay until a/c is switched off.

gtsyellow

:lol: :lol: :lol: been doing the same thing here in oregon, it's been 90 this past week and i have a set of cylinder heads i have to finish porting. the hose stays about 5 feet away to spray myself with every few minutes

tkrussell

I have the same setup, 160 stat, Hypertech reprogramming, and a HD radiator as well from TPIS (lot of work to install and baffle correctly) I run 25% Antifreeze and use Water Wetter. I have bypassed the throttle body as well.

My experience in summer (Texas) is 182 on the road, and 210-215 in traffic with AC on. The vette needs better fans.
In winter, 175 most all the time. No problem with warmup, engine PCM settings, heater output, etc.

In the summer, the fans are on high most of the time with the AC, so the settings are irrelevant. In the winter, the fans cycle between about 178 and 185 on low speed.

The thermostat temp (160) is about 15 degrees below the engine temp as measured by the coolant sensor on an LT-1 at steady state in cooler weather. Must be the Reverse Flow cooling system and the position of the sensor. So a 160 stat in a LT-1 acts a lot closer to a 180 stat in a L98 or other cars.

Lone Ranger

Well... I don't feel so bad now. Guess it just the way it runs and any fan activation setting below 195 is going to have them on a lot in summer, period, regardless of which tstat.