Thermostat Temp for TBI 350 LO5?

I bought a new thermostat on my yarding adventure yesterday but have not changed it yet. I bought a 180, but there were a 160 and a 195-degree showing up as options. 160 sounded way too cold, and the 195 was listed as the factory replacement, but that sounded too warm...so got a 180.

So, just to ask before I do this, who is using what in their TBI cars? Keep in mind it only gets below freezing here about 4-5 days a year. Would like opinions before I do this job.

Thanks in advance!

-Mike

Mike:

If the engine is stock, go with the factory spec temperature. The engine was designed to run at these temps. If in the summer you find the temps crawling up then the 180 could be considered. Typically, the cooling system and fans etc. were sized for the normal temperature fluctuations. Only time you should consider changing it would be if in your specific climate the system is not up to the task, see if the next lower range fixes or partially fixes the problem.

Too cold and your fuel mileage takes a kicking, not to mention that on the real hot days, your thermostat will remain wide open and could also result in overheating. Has to do with how long the coolant stays in the engine and your rad. Coolant needs time to absorb heat from the engine and time to dissipate that heat in the rad.

Stick with the stock thermostat unless you have done significant mods to the engine or your outside temps are too high.

Bill

convert2diesel wrote:

Mike:

If the engine is stock, go with the factory spec temperature. The engine was designed to run at these temps. If in the summer you find the temps crawling up then the 180 could be considered. Typically, the cooling system and fans etc. were sized for the normal temperature fluctuations. Only time you should consider changing it would be if in your specific climate the system is not up to the task, see if the next lower range fixes or partially fixes the problem.

Too cold and your fuel mileage takes a kicking, not to mention that on the real hot days, your thermostat will remain wide open and could also result in overheating. Has to do with how long the coolant stays in the engine and your rad. Coolant needs time to absorb heat from the engine and time to dissipate that heat in the rad.

Stick with the stock thermostat unless you have done significant mods to the engine or your outside temps are too high.

Bill

The OCC is bone stock. Thanks for the info Bill.

-Mike

the correct temp thermostat for the tbi350 is a 205, not a 195. it will not run clean at 195. you would have a difficult time to get it to pas an emission test with out a 205 thermostat.
even with the 205 thermostat in my 93 it runs in the lower 3rd of the temp gage never quite reaches the middle of the gage.

the factory service manual says to use the 205, but most store's computer catalogs list the 195 as the replacement on sbc 350's so they assume it's correct for all 350's, and that's fine if your engine is pre computer controled fuel injection.

Yours is a 1992 tbi 350 and it will run better with the 205.

buickestate wrote:

the correct temp thermostat for the tbi350 is a 205, not a 195. it will not run clean at 195. you would have a difficult time to get it to pas an emission test with out a 205 thermostat.
even with the 205 thermostat in my 93 it runs in the lower 3rd of the temp gage never quite reaches the middle of the gage.

the factory service manual says to use the 205, but most store's computer catalogs list the 195 as the replacement on sbc 350's so they assume it's correct for all 350's, and that's fine if your engine is pre computer controled fuel injection.

Yours is a 1992 tbi 350 and it will run better with the 205.

Wow that's really HOT.

I used a 195 in my 92 RMW LO5 and it passed the strict Ontario E test easily.

Mike.I put a 180 degree thermostat in my 91 OCC and lost about 2 mpg in the city and it never
seemed to run right until I went with a 195 and evrything went back to normal!

I did not realize a 205 T-stat was even sold, by anyone, never seen one! Most factory recommended T-stats are 195. Cooler will get more gas into the engine, poor mileage and a dirty tailpipe. Hotter will get more efficiency, as most factory tunes are designed around this temp of 195. Oh... the engine can be hotter, but regulated at 195. I myself would go with a 195, personal preference and experience.

engine stays cooler with 195,.especially in an old TB aiee
water stays in the rad longer, after a stat opens the water just starts chasing round and round,.
So many times i,ve put the 195's in and stops overheating in traffic,.
remember tho t-stats are not on off switches,.they gradually open and close,.
(for all you OCD types that watch guages for entertainment) electric guages are oft times reading waay off,.
LT1;s like 160's tho,.with the right programming,.

Nick