i didn't post this at first cause it is simple enough and widely known in the vette crowd, but sharing it here too. it is just bypassing the throttle body coolant lines. unless you live in alaska or somewhere super cold, this can be done with no reprocussions. coolant is run to the throttle body to help keep it warm and to defrost it when the temps get way below sub freezing. but in the summer it keeps your throttle body the same temp as your engine coolant, thus helping in heat soak to the manifold. simply remove both coolant lines on the throttle body, and splice back together.

 

1-2bhp at most...and I'm sure everyone here knows about this. There's more heatsoak from it being bolted to the plenum and the heads than there is heatsoak from the coolant.


but anyways, if that's really a concern, and you live in FL or whatever, why not just drain all your coolant out, flush it all, and just run distilled water/water wetter?

 

well in the land of needing to spend $1k plus on this car to see ANY hp improvement,a free tip is always appreciated. this is not meant to be a tire shreading improvement, lol. running distilled and water wetter will only help the car from overheating, past what the thermostat is set at. this is meant to help keep heat away from where it is not needed, thats all.

 

so when I pull them off will they spew coolant everywhere? and how do I connect them together? thanks

 

you have to either yank the other hose out from its location and replace or just get a hose connector.

like I said, you'd maybe see 1-2hp. It's such a negligible gain there's no way to dyno prove it because the average dyno can vary up to 5hp or more.

 

hmm in this yanking process, wont the coolant be spilling out everywhere?

and man I need some random projects to keep me busy, maybe itll only gain .5 hp, but I don't really care...

 

1-2 hp ?
lose a couple lbs or taking out the carpets would do the same thing
(i am talkin about the less weight more faster approach)

 

ill do both

 

Look into the Motordyne Isothermal gasket, coolant bypass valve and copper throttle body heater. The coolant bypass valve allows you to turn on/off the coolant flow. The copper TB heater only heats the TB, not the neck of the plenum. The isothermal gasket reduces the heat flow from the manifold into the plenum.

 

The tip is appreiated, thanks overZealous1. I wonder how many Z owners have actually done this?

 

I don't have my Z around (I'm away at college) so can someone help me visualize this for when I do get home to do it? So there are two lines running to the TB, and what I want to do is either remove both ends from the throttle body and one hose from its other connection, then connect the other hose into this second connection, leaving no connections to the TB?
or just remove both from the TB and connect them together?

 

i have not heard of it at all on the z forums, but it is a mod most vette guys do, and they will sell you a "kit" to do it on ebay or other places for $20-$25 for the vette, hahhaa. of course supplementing it with isothermal gaskets will help, but this one is nearly free. honestly, look at my sig, i am not trying to make the car fast by upping tire pressures and a bottle of octane booster. but especially for me, i want to keep as much heat out of anywhere i can.

 

oh by the way, lock a set of vise grips on the hoses before you pull them and you will loose hardly any fluid.

 

When I added a coolant valve very little coolant came out.

 

The original manifold bypass article for the Z/G35 was posted on our sister site:

http://www.g35driver.com/forums/showthread.php?t=49465

 

I was just gonna bring that up...

 

Yep, you got that right sir!

 

For those that want to do it on the cheap (doesn't the Isothermal kit cost like $50???), simply look up the Crawford Plenum install instructions on their site; these will help you with visuals and show you where/how things connect. Easiest way is to just disconnect the two tubes from under the plenum neck (stuff a rag around them while you pull them off to absorb the small amount of coolant that will leak out), then splice the teo hoses together with a 3/8" to 3/8" connector and a couple of clamps. Hard oart is that to gget to the hoses and clamps, you have to remove the intake tube and throttle body at the very least and if you aren't very dextrous, you may have to take the plenum loose as well.

I have the Kinetix composite plenum, which comes with a separate coolant block that bolts to the bottom of the plenum neck. Due to the composition of the Kinetix plenum, I doubt very much heat is transferred to the neck/throttle body by this setup anyway, but I installed a couple of nylon spacers and longer bolts between the coolant block and plenum neck (didn't have a connector and extra clamps on hand, or I woudl have just omitted the block altogether). If heat soak is your biggest bane, the Kinetix plenum is hard to beat; that thing doesn't get hot at all. Surface plenum temps run around 105 degrees and don't climb past 110 even after the engine has been shut off and heat soak really tends to get the metal plenums hot. This is at least 50 deegrees cooler than stock or Crawford plenum surface temps.