What temp thermostat do you guys run in your race cars? Or do you use a blanking plate?

The stat cover had been weeping, so I took it off to re-seal it only to discover no stat was fitted. This ties in with the PO's comments that the temp never went over 80. I had a Mk2 Escort back in the 80's and took the stat out after it over-heated a couple of times due to stat sticking shut, but with it removed it just never got up to temp. My car has an ali rad from a Golf fitted, so cooling capacity should not be a problem.

Cheers,
Shaun.

my pinto has a 88 degree stat in but then im running a 4 core westfield radiator only have to switch on the fan if im stuck in taffic

[Edited on 2/21/2010 by DRC INDY 7]

83c or 88c thermostat standard part as used on Xflo, BL Mini, MGB and most other 1960s cars.

Best to drill at least one bleed hole 2 to 2.5mm dia in the thermostat valve plate before fitting.

Be aware if you have a thermostat fitted you must have a by-pass hose connected or as on most 1970s Fords a heater in which the temperature isn't controlled by a water valve.

Be aware there a 2 different diameter stats fitted in the crossflow!

Hi

The majority of the racers do not use a thermostat. They chop the center section of the thermostat out leaving just the outer ring as a flow restrictor. If using a thermostat the one to use is the 74deg one. As the crossflow needs to operate at no more that 78 deg to produce best power. Getting the water pluming right is the most essential part though and using a header / expansion tank and return bleed from the rad and thermostat unit are essential to get the system fully operating to its best potential. Also using the smaller DIA crank pulley to reduce the water pump speed if using high revs on a track is a very good idea.

Cheers Matt

Thanks folks. When I said blanking plate I meant a flow restrictor. I've read that running without some form of flow restriction causes uneven cooling (probably not much coolant flow around #4 cylinder).

Matt - Do you blank off the small connection on top of the water pump? I assume originally it was just a return from the bypass/heater circuit. It's currently plumbed directly to the header tank, as is the stat housing, but I do not have a bleed connection on the rad.

I have a steel crank pulley, will have to check the diameter.

Cheers,
Shaun.

Hi

Yep the fitting on top of the Pump is used as a return. And as you have it plumed direct to the header tank is correct. Or alternatively blank the fitting of and plum the header tank return back into the cold return from rad closer to the rad. I do it that way so as to have less clutter with the pluming around the engine its self.

Not everyone can get a bleed from the rad particularly if using the Polo rad. Best solution there is to raise the rear of the car ( assuming the header tank is on the scuttle ) and run the engine till warm and squeeze the bottom hose gently a good few times to tease any air from the top of the rad back up to the thermostat housing which will bleed back to the header tank.
Or alternatively if you have the Polo rad with the bleed fitting blanked of just bled the air from there when doing the initial first few runs and then re seal with bung. Just keep checking for a good spread of heat all over the rad. IE no cold spots.

Cheers Matt