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1MZ cooled throttle body mod

4222 Views 10 Replies 8 Participants Last post by  Eye8Pussies
Many people have debated whether or not the coolant bypass mod is worth doing. Is there actually an increase in power with this mod in place? The theory is sound as with every 10 degrees cooler that your intake air charge is you will see roughly a 1 HP increase. When you engine warms to normal operating temperature hot coolant is being passed through the throttle body warming the air charge and robbing power. Nathan Morris, in a post on actually showed a gain of 10lb ft of torque with this mod is place that disappeared once his Integra LS engine reached operating temp. See dyno sheet below.

Of course there may be other contributing factors to the stronger pull with a cooler engine, the basic fact remains that a cooler air charge = more power.
This fact has been enough to convince many people to make use of the coolant bypass mod. I propose that this mod be taken one step further to keep intake temps from rising due to other influences such as direct and indirect radiant heat from other hot engine components.

Here is my idea:
1- Go ahead and bypass the throttle body coolant lines as you normally would with this mod by simply disconnecting the input and output lines and connecting them to eachother with a suitable fitting.

2- Get yourself a universal trans cooler like the one below for cheap from ebay.

3- Now get a cheap 12 volt marine water pump from ebay like the one below.

4- hang the new cooler behind your grill using ties like these.

5- Connect the cooler to your unused coolant lines at the throttle body and put the 12 volt marine pump inline. Connect switched power to the pump and mount it. Fill the system with the same water and coolant mix that you normally use depending on your climate. Your done.

I would have to say that this mod would indeed lower intake temps by a significant margin over simply using the coolant bypass mod. incontrovertibly this would add some power. How much I cannot say. However this would certainly be a great compliment to any CAI set-up.
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Interesting enough. I'll let someone else be the guinea pig first though before I try something similar; I've become quite attached to my current ProFlow TB/Injen main pipe/UPFD extension setup, and don't want to compromise it just yet by messing with it.
that would be a waste of money if that "theory" is correct. thats alot of money and time to spend for maby a few HP. with that setup youd only see a slight drop in intake temp. if you were so some how get 50 degrees cooler youd only be getting 5hp. you sure they dont mean 1% hp increase? cuz thats what ive herd from other discussions of cooler intake temps.
i have no problem with the theory behind this, but i think that the new mini radiator will be too close to the condenser and radiator, and it will absorb heat when you're moving slowly... plus the added weight of the extra fluid and the pump, plus the electrical drain of the pump... if you get any minimal gains, they will be lost by the minimal additions to the car.

then again, i'm only working on theory too - i do not have numbers to back me up and it would be pretty cool if i was wrong!
The temperature drop is too minimal to show any noticeable gains. By doing the coolant bypass mod, it drops 20-30 deg because it is going from hot engine coolant temps to regular engine bay heatsoak + having the TB bolted up to the engine. The real reason for this bypass mod is from the fact that it is free. Free means even affing 1 HP seems like a good idea.

By adding the pump and cooler, you are only getting down to ambiment temps. Even if you do drop 10 deg, you gain so little it won't even offset the weight gained and the load it puts on the alternator to drive the water pump.
thanks tony, you said it better than i could... and with real numbers.
The mod you just describe is essentially a crude intercooler. If you were running forced induction it might help a little(If you couldn't fit a regular intercooler)
The mod you just describe is essentially a crude intercooler. If you were running forced induction it might help a little(If you couldn't fit a regular intercooler)

Not even worth the effort for a forced induction setup... There is so little surface area on the throttlebody itself that even if the TB was frozen, it would barely do anything.

To severely drop IAT's on a naturally aspirated engine, the only method really is to install a CryO2 kit.
Sacrifice a lil' aero, and drive without a hood.

Just an interesting concept. The motivation behind this was reading that Nathan Morris lost his 10lbft of torque gained once his engine arrived at normal operating temp. I thought this might help to sustain lower intake temps for a longer duration and especially while cruising at highway speeds and in conjunction with other applicable devices such as a CAI. Again, how much of a gain vs parasitic loss I could not say without numbers to back up the application. Tony brings up a good point considering the relatively small surface area of the throttle body that would actually be coming into contact with the coolant/water mixture. Aluminum, while having excellent heat dissipation properties would be susceptible to radiant and direct heat sources from the engine. Would the setup keep the the throttle body and intake plenum cooler vs running 210 degree coolant through it? Absolutely. Would the intake stay cooler vs simply bypassing the TB coolant lines? Of course. Would the setup have the ability cool the incoming air charge enough to make an appreciable difference? That is debatable and would certainly differ from engine to engine. Is the additional load placed on the charging system a contributing factor to parasitic loss? Probably. However, if you like your music as much as I do you likely have an existing over-draw condition. Just my single MB Quart amp uses three 30 amp fuses. As far as the cost of this setup is concerned, in my case at least, being a mechanic I have everything I would need to apply this mod minus the $15 marine water pump lying around the shop. Otherwise total cost involved would fall somewhere in the $40-$60 range. Added weight to the vehicle? Anyway, there are obviously a number of factors to consider. At the least it makes for an interesting conversation.
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very interesting theory for sure....but I would say that the parts and weight associated would be better utilized as a water cooling (spray) kit instead of using it in this way. with a lot of the reasoning that the cooling effects of the cooler would probably not be much lower than the ambient temperature of the engine bay when moving anyway.

One thing it may help prevent though, is the heat from the block transferring up through the intake plenum and then to the TB. But a lot of people use different material TB spacers to try and deal with that if they think that it's a big problem.
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