tt061880

this is the mod you wouldn't want to do in cold climate states. The hot coolant run throught the TB to warm up the TB and the butterfly wouldn't seize up due to the cold. If you live down south then this is the mod worth doing. You don't need a kit for it and i doubt it will gain 8 horse power, maybe 8 rat power .

jimmyjazz

I used to own an ls1 Z-28, they have the same engine as the'98 to '04 Corvettes. This question has been asked a million times over on the ls1 and Corvette forums. The answer is usually 1-2HP if any but everbody does it! No one has ever ( as far as I have seen) had there throttle blade freeze up but that's why the coolant run's through the Tb. If you wanted to go and search you can try LS1tech.com or Corvetteforum.com and search there. The 'Vette's have fly by wire like our car's. I guess what I am rambling on about is, it won't really make any difference one way or the other.

FinanceGuy

Thanks for the input guys. It's good to know that I can come here and get so much help!

clubfoot

North Shore can get pretty cool with lots of moisture in the air depending on time of year. I was surprised at how many IS350s I saw on the roads there this past week,...at least seven, which is more than I see all year in TO!

Larry96815

Yes, I am am the only old man driving one. The rest are young good looking Filipino girls. (which is okay with me)

Aloha,
Larry

Ramon

Yep, been around for years... No way it will add anywhere near 8hp

Optimus

I think this paired with the turbonator should put you in the 12s.

Heltah

I've done this mod on 4 cars.
Didnt make enough HP to feel a difference at all. Although the throttle body is cooler to the touch now. I would also think that eventually (long drives) heat soak from the manifold will bring the TB temp up anyway. In the case of long drives the coolant may actually help keep the TB temp down.

IMO The amount of time the air is in the throttle body does not allow for TB to intake air heat soak. I would'nt do it to my lex. Then again I havnt done anything to her, performance-wise.

For those who want to try it and live in areas with winters. It takes about 2 minutes to do so you can return it to normal for freezing temps. You could even buy a small valve so you can just open your hood turn the valve, bam back to stock.

Gernby

iTrader: (1)

Bypassing the TB doesn't do as much for long drives as it does for stop and go driving. We also don't have to worry much about heat soak through the intake manifold since it is composite.

Regarding the valve thing, I think you would have to rig up more than just one valve since you can't just block the line. The valves would have to reroute the coolant.

lobuxracer

iTrader: (2)

The 4A-GE came from the factory with a thermostat in the throttlebody to control coolant flow. I haven't looked that deeply into the drive by wire units, but it wouldn't surprise me at all if there is also a thermo controlled valve in them.

Time to do some research...

Heltah

If thats true its the best setup!! Damn they're smart..

LOL I thought that would go without saying.
Actually 2 switched valves work better.

hose to TB
*switchable Y-valve
*length of hose
*switchable Y-valve
hose from TB

turn on off as you please
Of course Im no mechanic!!

lobuxracer

iTrader: (2)

There's nothing in the documentation indicating there is a thermo valve on the throttlebody.

I've been looking at other models to see if there is any reason to believe it might be, but I'm also not finding anything on it. My '88 GTS Corolla with the 4A-GE definitely had a thermo valve and had procedures in the FSM for testing the valve's operation. If I had one in hand...oh well...not worth breaking the cooling system just for that.