Throttle body coolant bypass mod

[oatmeal769]

So I'm searching around regarding the conversation here:

http://www.customtacos.com/forum/sho...t=82165&page=2

Spicy Taco has proposed running cold fluid through instead of hot fluid. We're still waiting to see if anyone knows for sure if cooling rather than heating the TB will lower intake air temps, or help with pinging, etc. in SC'd engines.
Has anyone done this mod and have any real proof, IE temp. before and after, or dyno gains?

I hope that if I can lower intake temps even a little, it will help me to be able to retard timing less in problem areas where there is pinging.

[QSVeilside]

Found these dynos online... which was why I performed the mod. It's popular with the LS1 and Honda crowd:

http://www.bmrfabrication.com/tb-dyno.htm

http://www.ultimateresourceguides.com/content/freemods/dyno1.jpg

[oatmeal769]

QS - Cool thanks for that, I wonder if anyone else has experimented with it on Tacomas.
Did you notice anything? Do you have ping, and if so, were you able to retard timing less, or get more out of your tune?

It seems to me this would be a really popular mod, if it works, it's probably as effective as a cold air intake. I wonder why it hasn't caught on with Tacomas?

[QSVeilside]

No prob Oat. As you have already pointed out with the link to the other post, a search yields several threads indicating that this mod has been around for awhile.

I would say that the gain is barely noticeable considering how fast the air is moving through the TB - not much time to heat up. If you've ever done back to back runs on the dyno without allowing the engine to cool down, you know that there is a loss of at least 5 rwhp due to heatsoak/fatigue by the third run. In other words, dynos that show roughly 5 rwhp difference need to be backed up with consistent runs showing the difference. Otherwise, I'd say they're almost worthless.

The fact that other car forums swear by it, provided dynos to demonstrate their results, (assuming they keep the above aforementioned observation in mind), it's relatively harmless, and MOST importantly - the fact that this mod is free, I consider it worthwhile.

If you've got the extra time to run down to home depot to pick up a brass double male 3/8" fitting and a couple stainless steel clamps to join the lines together, I'd say go for it.

[oatmeal769]

Yeah, you're right, it won't hurt anything to try it. I'll be able to know pretty quick if it helps with pinging too.
I was thinking the same as you - there's too much air going by too fast for it to make a difference, but I thought I'd read somewhere that it actually does. If so, running cold fluid through it might help too.

[Beef97]

Ok i've done a ton of googling and found hundreds of people with opinions on this one in either direction. Some swear by dyno results and others like Gadget write of freezing up the throttle body. My guess is that if Toyota manufactured these engines without the coolant lines going through the TB at all, nobody would even miss them. Am i missing something or is this freezing thing silly? And if it doesn't really do anything then why bother? Anyone have any evidence that removing it can throw codes or somehow hinder engine performance? Seems to be a strange topic at times....

thanks for all the input everyone!

[ArmsDealer]

Originally Posted by Beef97

Ok I've done a ton of googling and found hundreds of people with opinions on this one in either direction. Some swear by dyno results and others like Gadget write of freezing up the throttle body. My guess is that if Toyota manufactured these engines without the coolant lines going through the TB at all, nobody would even miss them. Am i missing something or is this freezing thing silly? And if it doesn't really do anything then why bother? Anyone have any evidence that removing it can throw codes or somehow hinder engine performance? Seems to be a strange topic at times....

thanks for all the input everyone!

Well i dont know about freezing them..
But this is a common LT1 /LS1 DIY mod.

If i remember correct your supposed to disconnect the coolant lines from either side of the TB and then plug the lines. so yes while you may no longer have hot coolant running through the TB, you do still have heat soak from the motor. its a 15-20 min mod.


I did do this mod on my LT1, I did not notice much of a difference.
In fact when connecting my Tech 2 OBD2 scanner to it the intake air temp was pretty much the same as before. if necessary i can do this mod and take pics but this is a mod that has been long beaten to death.
Its not going to make your car throw codes.

I never saw huge feel-able gains from this mod. it never made me throw any codes. and some people have dynoed this mod to put it out of its misery. but realize, thats a Chevy camaro or vette, not a Tacoma.

[QSVeilside]

As I mentioned earlier, a search brings up several threads indicating that this mod has been around for some time. Here are two respected gurus' opinions on the mod that were posted in this forum:


"Cold air like sub freezing will not cause ice to form in the throttle body. Cold air like that does not hold moisture so there is nothing to freeze in the throttle body.

It is warm weather that you may have the icing problem. Like warm very humid air. When the air passes through the throttle plate it goes from an area of high pressure to low pressure. This does two things. First there is a dramtic temperature drop and it can be as much as 30-40 degrees. Next what ever moisture is in the air can condense out and the two things combined can cause throttle icing.

So, you are more likely to have throttle icing when it is warm out then when it is cold.

I have never heard of anyone having any problems with this mod. If by some remote chance you do, it is easy to reverse. It is not permanent.

Gadget"



"It won't hurt a damn thing. There are a lot of people that have the coolant bypassed. I've had mine bypassed for at least a year. Noli's is bypassed. Xtrapsi has had his bypassed for a long time as well.

You guys have to remember---running coolant through the throttle body or carb is a relatively "new" thing at least in the automotive world. We never had this in the past and it worked just fine.

I did the bypass on my truck because we are having problems (not me yet) with the newer "throttle by wire" throttle bodies and I have a sneaking suspicion it is heat related. The APPS and the TPS are both plastic and I think the heat is having an adverse effect on them. The second reason is because when I got my system up and running, I happened to touch my throttle body and it was hot as hell. I thought to myself that I had invested close to 1K in a WI system to, for one thing, help cool the intake charge and yet I was pulling air through a heated throttle body that was at 190 degrees. I thought this just wasn't right so I did the mod and the throttle body stays nice and cool now.

Did I gain any performance? I really have no idea. I kinda doubt it but then again maybe. It does make me feel better that the throttle body with all it's plastic parts is now running cool and I have done everything I can within reason to cool the air charge and the combustion chambers.

TRDOLMAN"

http://www.customtacos.com/forum/sho...coolant+bypass

http://www.customtacos.com/forum/sho...coolant+bypass

http://www.customtacos.com/forum/sho...coolant+bypass

[Beef97]

thanks for the reply. I live in texas so the last thing i need is more heat.....plus any excuse to open the hood of the truck and play around a bit is all i need.....thanks guys

[DJDevynator]

i keep looking at this mod and thinking about doing it.

and even if it doesnt do much, its not like it costs anything, u just use the exsisting hoses. atleast with my 06 all i do is unplug the two holes and use each one to run everything into eachother.