More Horse Power & Gas Mileage

[wells service]

After (or before) cold air intake(cai) and cat back exhaust,whats next? when will the computer reprogramer be avaliable and will it void the warrenty? On the Gen 1 site (page 4- 12/4/07 under "has anyone used Perma cool electric cooling fan") Black MBJ says he got 5-7 hp and 2-3 mpg more by disableing or removing the radiator fan and fan clutch and cooling with electric fans. my research shows more like up to 10 hp and 1-2 mpg more by not spinning the stock roaring fan all the time. Even when the truck is cold and the fan clutch is supposed to be disengaged, the fan roars. It sounds like MBJ was using relays that came on too soon and were cycling on and off often and thus wore out. i did not buy a kit(although I like perma cool products) I have a shop discount at Kragen auto parts(checkers,schucks,murrays) I bought two curved blade(possibly guieter) Hayden 16" fans 1500cfm each electric fans for $100 times 2 =$200. Perform fans at Kragen with straight blades pump 2100 cfm each for $60 times two +$120. it is wise to buy a realy for each fan. you need the relay that has an adjustable thermostat for $90 x 2 =$120. preset termostat relays are cheaper but come on too soon. before you do any thing you should get your truck warmed up and put a thin white out line over the temperature gauge needle. now you can tell when the truck starts to heat over the water thermostat tempature. if any one wants more details about mounting, just post back and ask.

[guntech]

Headers. Doesn't look like programers are available yet.

[thumbster]

I'd be a little scepticle about the cfm ratings on those fans based on the way they are rated (pressure drop, etc.) I've dabbled around with electric radiator fans for a while now and have come to the conclusion that you don't get something for nothing. The better fans that move a good amount of air cost accordingly and draw a significant amount of current. You also have to take into account the extra cooling you will need when you run at slower speeds with any kind of payload or towing. There can be a significant benefit to running electric cooling fans in terms of mileage and power, but you also have to understand Toyota put a great deal of research in the clutch fan setup in our trucks. It's a pretty efficient system that works very well, but there's always room for improvement. A word of warning - don't even bother to try those direct mounted fans that have the tye-wraps going through the radiator core. The airflow will never get fully dispersed over the whole radiator core and there's a lot of strain on the core itself from the weight of the fans.

I was planning on trying some Permacool fans with a custom shroud. I was shooting for about 6000 cfm total airflow and controlling the whole thing with a PWM speed controller. You'd have to take the temp readings off the stock coolant temp sensor for an accurate reading. One would have to document the resistance curve for the entire temperature range for good temperature control. Running the fans at a partial, more constant speed will the temperatures more consistent. Keeping the temps stable is the key to reliable operation and better gas mileage, also for the sake of the charging system's lifespan. If someone already has done some research on this please let us know.

[wells service]

thumbster has some good points. the "electric fan only" may not be good on a truck used to pull very heavy loads especially in hot weather. removing the stock fan and fan clutch would probably vold the warrenty, but draining the oil out of the clutch and leaving the fan it in place may not. you thread the hole you used to drain oil out of the fan clutch and put in a bolt that can be turned in to lock up the fan if the electric fans can handle the load. the need for speed controls can be avoided by adjusting one of the two relay/thermostats to come on as soon as the temperature needle moves off the thin white out line you put on the normal needle position. when i pulled two dune buggys on a trailer up cahon pass(out of LA) at 65 mph, the fan or fans did not come on unless a semi was in the 2nd lane and slowed me down. two 1500cfm fans handled any situation. two 2100cfm fans would be even better. the fans seldom come on except for slow traffic in hot weather with the air on. there is a conection on the relay/ thermostat to turn a fan on when the air cond comes on.