Frankly any gains are probably negligible, like replacing air filter with K&N, but has anyone here done a throttle body coolant bypass? This was quite popular when I had my Corvette with those guys that were looking for any way to squeeze that extra 1 or 2 horsepower but the idea sounded logical. For those not familiar coolant is run through the base of the throttle body to deal with cold weather conditions but the need for doing that is questionable in places like California or Arizona, etc. The goal always seems to be getting cooler denser air through the TB and disconnecting the coolant lines presumably reduces the temp a bit.

Anyone ever done this here?

Doug

 

I thought that it was there for cooling due to the egr.

 

I don't think so. What I always understood was that this was done to heat up the throttle body in colder climates.

Doug

 

Potential gains are even less than the elusive promises of certain air filters. The amount of heat transferred to the air rushing by is so slight that even the most sensitive of dynos would have trouble detecting any gain.

Rule of thumb is that it takes an 11*F decrease in inlet air temp to realize a 1% increase in power. I'd be surprised to learn that a heated TB contributes 1/10th of 1 degree to the inlet air temp.

 

Everyone agreed that the potential gains were negligible or less. But there is just a certain degree of fun and sense of accomplishment in doing some small tweak like this. Similar tweaks included throttle body air foil to improve the air flow into the twin bore units that were used on the LT-1, relocating the MAF temperature sensor to a cooler area so that the computer would make the air fuel ratio richer, replacing the fuel pressure regulator with and adjustable one and then playing with the pressure, putting in a lower temp thermostat, etc. Each of these tweaks was claimed to be work a couple of horsepower and there were always those guys who deluded themselves into thinking that if they added a number of these they suddenly "found" an extra 50 horsepower!

Still, even though most understood the truth, there were a number of aftermarket manufactures selling kits to do these things so there was obviously a market.

Doug

 

Not sure I agree that 'most' understand. There's too large of an aftermarket supplier and snake oil purveyor trade making a go of it if only a few believed in miracles.

A major advertiser on one of the Corvette discussion boards is doing very well by selling kits that allow owners to gain 20+ HP by disabling the smog pumps. Despite several of us posting GM documentation demonstrating that the smog system actually consumes less than 1 HP, sales continue.............

 

Very true. Same thing with the exhaust systems. It was not uncommon that the first thing an owner did was to replace the exhaust system with some Borla or other expensive piece of junk. Noise of course was better so you were "obviously" gaining power but dyno measurements rarely showed much of an increase for the money you were spending. Same thing for replacing the throttle body with a larger bore. While it sounded like something good to do the penalty was less responsiveness and poorer performance.

Still I wouldn't mind doing something cheap and easy like the throttle body coolant bypass since there is obviously no need to further heat up the TB in places like California. I'd rather have the coolant circulating around where it would be doing some good.

Doug