Engine running hot

[Joseph Adamek]

Hey all, just picked up my 71 Challenger with a 512 Stroker engine with Holley Sniper Fuel Injection, and it runs HOT!

Has a 180 degree T-Stat in it. I wanted to put a 160 in, but the person who sort of "finished" the car for me said it needs to have a 180 because of the Holley Sniper FI in it.

Anyone else having these issues? What are you doing?

Thanks, Joe

 

[Bret Schneider]

Yeah you'd want the 180 degree thermostat with the Sniper system to ensure the computer goes into a closed loop condition once it's warmed up. Has the cooling system been upgraded to handle the extra heat the stroker engine is going to produce? Mainly the radiator size and cooling fan(s) need to be considered.

 

[Joseph Adamek]

Yeah you'd want the 180 degree thermostat with the Sniper system to ensure the computer goes into a closed loop condition once it's warmed up. Has the cooling system been upgraded to handle the extra heat the stroker engine is going to produce? Mainly the radiator size and cooling fan(s) need to be considered.

it has. The one thing I can think of is I don't have a shroud around the fans because the ones that came with the fans I couldn't use.

 

[Bret Schneider]

Definitely want to have a shroud around the fan otherwise you'll likely have temp problems at idle and low speed driving. Maybe consider electric fan(s) if need be. No need for a shroud with those.

 

[MoparCarGuy]

Your Sniper EFI has settings for when it is in Closed or Open loop. I am running a 500 stroker RB engine with Holley Sniper Terminator X Stealth EFI, a 195°F thermostat with factory 7-blade clutch fan, shroud, and radiator. The EFI works perfectly within your typical engine operating temps.

 

[Joseph Adamek]

Definitely want to have a shroud around the fan otherwise you'll likely have temp problems at idle and low speed driving. Maybe consider electric fan(s) if need be. No need for a shroud with those.

I have electric fans, but the shroud that came with them I couldn't use because it stuck out to far and was hitting the serpentine system I put in.

I'll have to try some cardboard first and if that works I'll make one out of aluminum. Thanks

 

[pschlosser]

Define

... and it runs HOT!

Define what you mean by "HOT"

Because if your cooling system is efficient, then with a 180F thermostat, the engine would be running around 180F, which is around the middle of the engine coolant temperature gauge.

If it is going into the H end-zone on the gauge, you're right, its running too hot around (in my experience) 215F+

My point is you may have a cooling efficiency issue to solve, before fine tuning the 180F thermostat. By cooling efficiency, I'm thinking your fan and setup is not able to keep the engine cool.

Looking harder at a shroud may be enough to keep things cool. Even my 10 year old minivan has a fan shroud.