Let’s talk about the H word - heatsoak

Blown_90LX said:

Hey Guys,

I’m serioisly looking at S/C kits for the 2018. My last blower car had a lot of heat soak with a Vortech. Looking for something to provide fairly consistent power and don’t want to have to swap-in different heat exchangers, etc.

I’m looking to hear from folks with either Edelbrock, VMP, or Roush/Ford Racing blowers about first hand experience regarding heat soak on the street.

Not looking for another Centri blower and have no interest in a Whipple, so please just folks running the blowers I mentioned earlier.

Thanks!

Click to expand...

I had a Roush tvs2300 on my '11 stick. I put 25K miles on it. Took it to the DS multiple times and would race it 1/4 mile over and over again at test and tune. Once it was 93 degrees. The times were consistent. If there was any heat soak running 1/4 mile times 5-10 minutes a part I was not aware of it. Just ran consistent. Fantastic performance. It's why I am doing the LMS 675 Magnuson kit as it is very similar to the Roush.

I had a Vortech as well air/water intercooler but never took it to the track. It was cool sounding but a bit more finicky for me at least. And no instant torque.

Blown_90LX said:

Hey Guys,

Thanks for the great feedback. Sounds like it’s not a huge issue. I do live in the South so I’m trying to plan for those 98 degree regular summer days.

I’m really digging the upcoming Edelbrock kit. I like the idea of using a trunk and/or Underhood water system like BoDuke said like the PBH Ice cell. Anyone know how that plumbs in to something like the Edelbrock or similar kit?

Also, anyone ever use a water injection system like the one Snow makes to either spray the heat exchanger or even directly into intake tract? Saw the new BMW had a factory water injection system that was good for an extra 50 horse due to cooling effect.

Click to expand...

Cooling the heat exchanger with water doesn’t do a lot, the BMW uses air to air which has a much better conversion rate when adding cooling to the surface, especially nitrous.

Ice tanks are great but you have to be extremely cautious of getting air out of the system since the tank is lower than the intercooler. Most ice tanks have a simple fill cap, which is not great for pushing air out.

Whipple SC said:

Cooling the heat exchanger with water doesn’t do a lot, the BMW uses air to air which has a much better conversion rate when adding cooling to the surface, especially nitrous.

Ice tanks are great but you have to be extremely cautious of getting air out of the system since the tank is lower than the intercooler. Most ice tanks have a simple fill cap, which is not great for pushing air out.

Click to expand...

Thanks, I appreciate the solid insight. Glad I asked and didn’t dump money into a custom h2O sprayer if the gains would only be marginal. The ice tank trapping air pockets will warrant some consideration too...

Blown_90LX said:

Thanks, I appreciate the solid insight. Glad I asked and didn’t dump money into a custom h2O sprayer if the gains would only be marginal. The ice tank trapping air pockets will warrant some consideration too...

Click to expand...

The Watson tank that replaces the battery is better for daily drivers, although I'm not sure its still available. Trunk mount is best for racing. Also, trunk mount requires larger pump or dual pumps because the pressure loss with long lines is not ideal. The Watson setup was the highest point in the system so it burped itself, the trunk is super lower so they are a pain to bleed.

I always think when talking about heat soak we focus too much on IAT and not enough on CHT.

Seems more effective to keep the whole motor/everything under the hood cooler with cooling mods, than to try to fight HE by keeping the air charge cool.

I mean isn't heat soak really when the motor, blower...everything has gotten so hot that the car can no longer keep temps in check without pulling timing or worse?

Whipple SC said:

Cooling the heat exchanger with water doesn’t do a lot, the BMW uses air to air which has a much better conversion rate when adding cooling to the surface, especially nitrous.

Ice tanks are great but you have to be extremely cautious of getting air out of the system since the tank is lower than the intercooler. Most ice tanks have a simple fill cap, which is not great for pushing air out.

Click to expand...

Are you saying air cools better than water here?..........

SVT-DADDY said:

I always think when talking about heat soak we focus too much on IAT and not enough on CHT.

Seems more effective to keep the whole motor/everything under the hood cooler with cooling mods, than to try to fight HE by keeping the air charge cool.

I mean isn't heat soak really when the motor, blower...everything has gotten so hot that the car can no longer keep temps in check without pulling timing or worse?

Click to expand...

IAT's pre and post compressor is King. Hot combustion event, with coolest incoming air charge into the combustion chamber is optimal for power. So the motor and heads need heat not too much not too little. Air charge is where it's at and is why there isn't so much effort and talk on the topic.

This coming from the guy with the MMR head cooling mod listed!

^^^^Respectful Ribbing^^^^

Remember the Renegade class back in the day? These guys were running 9.0's 20 years ago with 5.0 pushrod motors using pedestrian parts and no intercooler. Back before everything was intercooled and every car had a IAT gauge we had to focus on controlling coolant temp(didnt know the term CHT yet).

Now I am not suggesting IAT's aren't important or that blowing 300 degree air into the engine is acceptable. However if you've got a 1" radiator with a huge HE in front of it and no other cooling mods your going to have trouble cooling the car down on hot days.

On a totally different subject I don't understand why guys don't let there cars cool off a bit before shutting them down. No coolant flow,no fans,no air flow are a recipe for heat soak all day long.

Roh92cp said:

IAT's pre and post compressor is King. Hot combustion event, with coolest incoming air charge into the combustion chamber is optimal for power. So the motor and heads need heat not too much not too little. Air charge is where it's at and is why there isn't so much effort and talk on the topic.

Click to expand...

SVT-DADDY said:

This coming from the guy with the MMR head cooling mod listed!

^^^^Respectful Ribbing^^^^

Remember the Renegade class back in the day? These guys were running 9.0's 20 years ago with 5.0 pushrod motors using pedestrian parts and no intercooler. Back before everything was intercooled and every car had a IAT gauge we had to focus on controlling coolant temp(didnt know the term CHT yet).

Now I am not suggesting IAT's aren't important or that blowing 300 degree air into the engine is acceptable. However if you've got a 1" radiator with a huge HE in front of it and no other cooling mods your going to have trouble cooling the car down on hot days.



On a totally different subject I don't understand why guys don't let there cars cool off a bit before shutting them down. No coolant flow,no fans,no air flow are a recipe for heat soak all day long.

Click to expand...

Agreed that good equal and stable CHT is also important. If you're heat exchanger is causing engine to overheat then again timing will be pulled out. It's a balance for sure to keep stable CHT and have maximum IAT reduction when racing or driving aggressively on hot days. Always a challenge, and always a good topic Tom discuss.

I've done many heat reduction Mods on my car from more airflow through the engine with modified front end and massive heat extractors. I've also attack heat absorbtion through the inlet by creating a completely closed Whipple airbox that is feed via Velosatech Big Mouth Ram Air cone that rams air from the front of the grill pas the HE and radiator. I've also insulated my intake system and run a small shot of meth injection. I'm like that.

EDIT: Yeah...head cooling mod I know:headbonk:

Roh92cp said:

I've also attack heat absorbtion through the inlet by creating a completely closed Whipple airbox that is feed via Velosatech Big Mouth Ram Air cone that rams air from the front of the grill pas the HE and radiator.

Click to expand...

I am going to do the same, and one of the those Foster SC whiny thingys.

Blown_90LX said:

Also, anyone ever use a water injection system like the one Snow makes to either spray the heat exchanger or even directly into intake tract? Saw the new BMW had a factory water injection system that was good for an extra 50 horse due to cooling effect.

Click to expand...

Water/methanol injection is one of the best ways to cool IATs. Injected into the intake pipe (post-MAF) lowers the air temp and adds octane letting you run more timing as well. In turn it lowers cylinder temps/pressures.

On my wastegated Procharger I was seeing +40 over ambient IATs at WOT. After adding meth injection I now only see +20. On a 3rd gear pull the temp actually drops below ambient until it shifts into 4th and it then starts climbing slowly.

I know you weren't looking for info on other blowers, but this just shows how well meth injection helps cool things down regardless of what setup it's used on.