which to use

[Ont67shortbox]

do you race guys use a thermostat or restrictor plate in your thermostat housing,what brand and size, thanks for the help

[vin63]

How efficient is your current cooling system and what type of system? When I ran Super Gas/Street, there were often 200+ cars in the staging lanes and I would sometimes be shut down for a a couple of hours to running within a couple of minutes of reaching the staging lanes. My target water temp was 190-200 degrees by the time I lit the second stage bulbs. I also ran a lightweight small radiator with a high volume electric pump and fans - this gave me the flexibility to run the water pump and fans independently. Because of this, I didn't run a restrictor or thermostat. I warmed my engine up in my pit just in case they ran my lane immediately, but would be aware of where I was in the lanes and how quickly they were running us to make sure I had enough heat in the engine by the time they pulled me into the water box.

Some of the guys who ran a belt driven water pump off of the crank pulley and/or had very large radiators sometimes struggled to reach their target water temp (the cooling system was too efficient), so they would run a restrictor

[71Dragtruck]

I run a restrictor plate, electrc pump and fans that I can run manual or auto along with a big ass aftermarket aluminum rad, I like to be at 160 for my burnout. I have the Moroso kit and have to look but think I have the 1" in right now, maybe 3/4" hole with my new pump.

I have ran into and seen in the past where plate size had to be adjusted to a smaller size due to the fact the water was running through the system too fast and caused overheating on the street because water wasn't in the rad long enough to cool down.

For strictly track like vin said not a problem where you want temp to come up fast moving to the lights and then once back in the pits I charge and run the pump and fans till cooled down anyway.

Guess what I'm getting at is makes a difference if you street drive it too, or just strictly race it.

[Ont67shortbox]

Thanks Guys, just a race truck now,cant get insurance here with tubbed/fuel cell/caged vehicles, so took it off the road,had 160 thermostat in but thought a restrictor might work better

[71Dragtruck]

I'd try a 3/4" and see how it is with that, moroso kit #63440.

[Ont67shortbox]

Thanks

[Marv D]

My scenario is a lot like others...Water temp as COLD as I can get it sitting in the lanes (after all the block wasn't 200° when they honed the cylinders with a torque plate to make it as round as the machinist could) ,,

But more important OIL TEMP above 150°

Sitting in the lanes is a balancing act of getting the coolant temp down, without chilling the oil. A high volume pan and sportsman diaper helps hold in heat in the oil. I drive to the lanes and idle till I have 160° + oil temp. Then shut it down and run the cooling fans and H2o pump to get water temp <140. You can't cool in the lanes with a thermostat. When I'm 3rd in line I fire the motor and see where I am for oil temp,, sometimes I shut it down and wait for the call out... sometimes it's too cold and stays running.

[vin63]

Originally Posted by Marv D

...(after all the block wasn't 200° when they honed the cylinders with a torque plate to make it as round as the machinist could)...

No, but the volumetric efficiency and combustion characteristics are optimized when the engine, particularly the cylinder head, is at operating temperature (SBC is typically 200-220 degrees). The thing to keep as cool as possible is the intake charge. In my case with aluminum heads, through many dyno sessions, my engine was most efficient (brake specific) and made the most horsepower when the water temp leaving the cylinder heads was 200 degrees. Just something to think about for racers who are trying to squeeze as much consistency from their combos.

[hotrod 80]

I actually use a thermostat with 2 small bypass hole drilled into it . I have the old Moroso belt drive pump and a single puller fan . I can run in manual off or automatic with temp sensor . I warm the motor well going through tech and it keeps the heat for quit a while . E85 is different also .