is this a good idea to do. pros and cons of this mod would be great. i herd the evo runs hot from the factory but also herd the stock thremostat was the best for are motor and is needed cause we need to run under serten temps. or am i stupid. help please.

 

I think that a low temp thermostat will only be a good mod if you makes too much power raising the engine temp suddenly. In this situation you would be safer because you low temp thermostat would be opened sooner avoiding an over heat condition.
Some performance ECUs need a low temp thermostat like HKS kansai unit.
I installed it and I can't say if it is a good mod or not. I would say that it made my car run rougher and every time I stop at a stoplight my rpm climbs to 1600rpm and after some seconds it come back to 900rpm. I read here somewhere that it is indicating a rich condition.

If I were you I would spend the money somewhere eslse

 

great post. thanks alot.

 

unles you do ALOT of roadracing, or live in the desert, don't bother

 

I guess this same advice goes for upgraded radiator caps as well right Adam?

When I had my 95 Integra, I upgraded the thermostat and radiator cap at the same time.

 

I tried the themostat, had same rich symptoms as k270. I pulled it.
I do run a greedy 1.3bar rad cap. This doesn't really make car cooler, just raises boiling point to avoid steam pokets.
I also run distilled water and waterwetter only. You can only do this if there is no chance of freezing temps.
This improves the cooling over water and antifreeze.
If you live in cold areas, try it next summer.
I live in AZ desert, I need all the cooling I can get.
It was 78F yesterday here and 80F just down the road.

 

I came back to the stock thermostat, no more rpm climbing at stop-lights.

I do not recommend this mod.

 

How does a thermostat affect idle RPMS ????

 

The thermostat affects the water temp, which affects the signal of the ECT sensor, which influences the fuel mixture as determined by the ECU. If the ECT is low, the ECU goes into 'warmup' mode, and richens the mixture, sort of like a virtual choke. This affects not only idle quality, but fuel economy as well.

 

OK, makes sense but the Ralliart only differs by about 10 degrees C. The stock thermostat would be kicking open at about the same time too. Does that really account for the big difference in the idle?

 

my friend just swapped out his Ralliart thermostat back to the factory one. he broke 2 of them in 2 years time. if your going to get one I dont suggest RAlliart

 

would it work better with a hks v pro? since u can tune for it?

 

Tune for a thermostat ??? Wartalon HELP !!! jk

 

obviosly not dude. I meant tune for the idle and fuel so the idle isnt so bad.

 

Apparently, the Ralliart t-stat does not kick in about the same time as the stock one, hence the idling trouble.

I see little rationale for spending that kind of money for a $2 t-stat regardless. Caveat emptor