axr6

I've looked over some of the threads regarding the changing of the coolant thermostat but, not seeing one aspect:

Is there a permanent or replaceable gasket between the engine block and the thermostat housing? I purchased my 170 thermostat from Summit but, it came without a gasket. Do I need to purchase one? Sources?

robert miller

yes you need a gasket for sure that is if it don't have a O ring in the middle of the housing. You have to use a gasket no way metal to metal will seal 100%..

I went with the LMR set up works great.. Robert

BJ67

The new stat should have a gasket/Oring around the outside. No gasket between the block and the housing.

BJ67

Be careful, if the summit stat is like or is the lingenfelter stat, you will have issues with the outer seal splitting and start having slow warm ups in a 1000 miles. There is a great post with pics regarding this problem on this C7 tech section. I have it saved in my favorites and do not know how to attach it here. Compare the pics of the lingenfelter stat to summit's.

axr6

Interesting. I specifically remember reading in some posts that the Summit 170 thermostat has a better, molded seal that does not come apart. Would love to see any discussion to the contrary.

BJ67

Lingenfelter sold 160,170, 180, they all did the same thing. Mightymouse did the post, I am trying to attach it.

https://www.corvetteforum.com/forums...is-repair.html

Seannyc

I got the 170 t stat also from summit racing they say it's the new housing no issues since I got it on 500miles on it

U shouldn't have any issues

BJ67

I just got a refund on my Lingenfelter unit, they have not come up with a revised unit yet. I hope the Summit unit is a totally different design. Compare the OE seal and thermostat unit, the seal is built in. If the summit unit looks like the Lingenfelter unit, I would monitor your warmups after a good 1000 miles. You have to wonder how many manufacturers other than 1 actually made this particular style stat.

EcoBrick Bob

It is definitely different. I have had both. Summit is currently installed and works great. Using the 170 deg T-stat with stock tune has not given me any codes. Been in for a couple months now. I had both 160 and 170 from Lingenfelder and both failed, even though I got the burr off the stock spring. The seal gets loose and pinches when closing. Eventually the gasket rips.