CLT or CHTS?

[DuoWing]

I'm planning to convert to MegaSquirt soon and I've been reading as much as I can. I think I'm pretty much ready to order. The only thing I'm interested in is what people are using or if there's a difference. I see a lot of people using the CHTS for the CLT sensor in MS and I managed to find the thread with the values for the actual datsun coolant sensor to put into MS. My only real question is if one is better to use vs. the other? I know the CHTS would reach operating temps much quicker than the Coolant sensor, I don't know if this would make a difference, or if it's better to go with the coolant sensor? Also I'd assume that the coolant sensor should theoretically see lower overall temps than what the CHTS would probably report. Just something I was curious on.

[skirkland1980]

The gm coolant temp sensor will thread into the right housing. It works with no mods to ms.

[LanceVance]

My only real question is if one is better to use vs. the other? I know the CHTS would reach operating temps much quicker than the Coolant sensor, I don't know if this would make a difference, or if it's better to go with the coolant sensor? Also I'd assume that the coolant sensor should theoretically see lower overall temps than what the CHTS would probably report. Just something I was curious on.

The CHTS is generally considered the better option. Temperatures around cylinders 5&6 are typically higher than the others so it's good to have the sensor near there to quickly read when they are getting too hot.

 

The thermostat housing will always read slower and lower than the CHTS. The GM sensor threading in (despite it not being the same thread size/pitch I might add) is the only real advantage it has going for it. If you've got the CHTS already, along with the conversion values then I don't see any reason to change over to the GM unit.

[winstonusmc]

The other day while tuning my CHTS was reading about 220 and the coolant temp was normal. Came off the boost and the temps dropped and the coolant stayed the same.

[LanceVance]

The other day while tuning my CHTS was reading about 220 and the coolant temp was normal. Came off the boost and the temps dropped and the coolant stayed the same.

Sounds like you may have been experiencing cavitation in the heads coolant passages?

[Tony D]

I mapped the Nissan pairs to CHTS and will never use CLT again.

We did extensive testing on an. Instrumented engine dyno, and the CHTS is much more representative of what is going on in your engine under load. If you are turbocharged especially, this is THE area you want to monitor!

 

It doesn't matter WHERE boiling starts in a head, once it starts, you're sunk. And on our cars, if it's going at start, it will start there.

 

Advantages of using it also go towards fuel economy...reaching ops temperature faster means less wasted cold start enrichment fuel, earlier closed-loop operation, etc....

[DuoWing]

Thanks for the info guys. I had seen people talk about using it, but it seemed to be most people were using it just because it was already there. Does make sense then to have it seeing the higher temps quicker than what the coolant will see.

[SleeperZ]

It seems obvious to me, but maybe it needs clarification, the Nissan sensor must be used if you sense at the cylinder head.  I wouldn't think the GM sensor is shaped properly to sense at the head as is not immersed in coolant there.

[winstonusmc]

You might be able to put a different sensor in there if you put some type of liquid around it, maybe grease to help with heat transfer.

[DuoWing]

Yeah I know that the CHTS would stay, I was just curious because a lot of people said they were just going to use, and I noticed some discussions about the temp differences between the two. So I was just curious if one had an advantage over the other. I'm percectly happy with using the stock CHTS. One less thing I have to add in, or figure out where to add in.