i just installed the heath heavy duty cooling upgrade for my 94 suburban. i was looking around and noticed other company's sell a similar upgrade- but most seem to go to the dual thermostat setup (Heath doesn't). the heavy duty water pump is the same for both setups- i was just wondering why some company's suggest to go to dual thermostats and Heath would suggest to stay with the single thermostat- would anyone like to give ther best opinion?

IMO the only benefit of duals is in the event one fails closed you'd have some insurance.

So far, I've been running the dual stat manifold with the stock pump.

I never over heated before or after the conversion.

The only problem I have is since converting my engine takes alot longer to heat-up to my desired operating temp, in fact it never gets up to the temp I want it at 205 degrees.

The only reason I can guess for this is the different design in the t'stat's themselves the original blocked the circuit going back to the pump while it was in the open position. The 97+ doesn't do this.