A engine waterneck question

[IMNCARN82]

Sooo.  Is the Chevy waterneck the same as the A engine ?  I'm looking for billet 90*.  So I'm wondering if it will work.  Not many options.   Thanks. 
R/T

[YellowThumper]

Best I can find is the answer is no.
Thinking back thru the years. Chev housings have always looked smaller at their mounting bases.

[IMNCARN82]

So yes but no thermostat. Ha.  Yea. That's what I thought.  Thanks.  I'll prob. Just modify the cast one from Mancini then.   

What's the drawback from no tstat? This car has no heater.

R/T.   

[YellowThumper]

No thermostat could go either way.
May run too cold all the time or end up getting hot because there is too much flow and water does not spend enough time in radiator to effectively cool.
This would be old school motor. If you have new gen. Then ya need the heat proper for all the electronics to be happy.
At minimum run a restrictor plate sandwiched between 2 gaskets.

[Chryco Psycho]

The engine will warm uo faster with a T stat , it also can run too hot without the T stat in place , Best to run a 180 or 190 *

[HP2]

Moroso, Mr Gasket and a few others used to make water neck restrictors that were designed the slow down coolant flow for cars without a t-stat. They were simply a set of t-stat OD sized washers with various sizes of holes in the middle to restrict flow to varying degrees.

[RUNCHARGER]

Engine wear increases without a thermostat and efficiency decreases.

[dodj]

Engine wear increases without a thermostat and efficiency decreases.

This exactly. The engine is supposed to be at a certain temp range. Once the engine is warmed up to 180-190 (whatever the original spec) all the parts have expanded to fit together as designed.

[YellowThumper]

With the ride you already have....
Overall it wouldn't cost much to have a custom one machined. Could even purchase the one you are looking at and have a base to it machined that fits what you need.

[IMNCARN82]

Thanks all!   Yea I'll just run wut I brung for now I guess.  Can always tinker later.  I agree.  Should have a tstat in there. 

[HP2]

The bolt pattern for them is the same, so yes, the housing will bolt to a mopar manifold.  However, as pointed out in yellowthumpers attachment, the t-stat diameter and location within the housing is different.  Mopars sit in the water neck recess, chevys sit in a manifold recess. So you will need the recess machined into one or the other to retain use of a t-stat or flow restrictors. 

https://www.holley.com/products/gaskets/other_gaskets/parts/738G

[IMNCARN82]

Couldn't I use a Chevy tstat ? 

[HP2]

Sure, but you still need to  have a recess milled into either the housing or the manifold. Chevy put the recess in the manifold so their housing  doesn't have the lip. Mopar put the recess in the housing, so the manifold doesn't have the lip.

Using a chevy t-stat housing with a mopar manifold means there is no step in either one to hold the t-stat. You might get away with using multiple gaskets to seal  above and below the 'stat, but it is a leak risk.

Using a mopar housing and a chevy manifold means you can use either t-stat.