This afternoon when it was over 95 deg I was 8-10 mph slower at the end of the straights from my speed in the cooler morning sessions. And in my morning runs I had a 180lb passenger and a full tank of fuel. So my runs in the afternoon with no passenger and a nearly empty tank should have (and have always in the past) been quite a bit quicker.

I've run the S2000 on very hot track days before, but have never run into this. I think it was simply heat soak, but I wonder why it never affected me before. I'm somewhat concerned as it didn't seem to affect the other S2000's at the track today.

I am running a metal grill (expanded aluminum) on the intake, but no front plate. I'm thinking perhaps I need to flush my cooling system, it's nearly 2 years old. I'm also looking into an aftermarket thermometer or perhaps a CAI to solve the issue.

Any suggestions?

 

Are you sure it never affected you before? Maybe it was just colder when you were running faster? 95 degrees is pretty damn hot.

Anyways, a CAI will help, and probably a heatshield between the engine and the intake piping (CAI). A lot of people have gotten heatshields made from carbon fiber.

When I was at Willow Spring (big track), my car was heat soaked to hell and was running significantly lower boost. I could feel the slowness of my car very easily. When I was driving back home to cooler weather (thank god for the beach), I was running full boost again and felt much faster.

Supposedly the S2000 runs pretty damn sluggish on hot days.

 

I'd definitely get rid of that choker grill thing. Did you hit 4 bars on the temperature gauge?

8-10mph seems like an excessive amount of speed lost due to heat soak. Odds are it had more to do with driver fatigue and tire wear than anything else - were you hitting the same speeds coming out of the corners?

At Willow Springs when the temperature went from 90 in the morning to 107 in the afternoon, I was losing maybe 2-3mph.

Good luck!

 

Heat soak probably had some to do with it but I am sure there were other factors. Did you monitor your exit speeds from the corners that went on to the straights? I imagine that as the track got hot your tires lost some traction and you were not carrying the speeds through the corners that you were in the morning therefore losing some speed also down the straights. I find that this happens allot at tracks in my area (Texas).

 

[QUOTE]Originally posted by jzr
[B]I'd definitely get rid of that choker grill thing.

 

The bug grill has to go for the track. Yes it has holes but that's not the point. The small openings have a big aero dynamic effect. They create turbulence and increase pressure on the outside of the grill causing the air to divert around it.

Lose it and you should be fine through the mid 100's. Above 110 there isn't much you can do.

 

[QUOTE]Originally posted by jzr
[B]I'd definitely get rid of that choker grill thing.

 

[QUOTE]Originally posted by Mikey
[B]First I'm going to have my cooling system flushed, it's never been changed and I'm guessing it might not be working to total efficiency.

 

That other guy in the Silver S2000 actually picked up a good amount of speed in all of that heat.

My last session, I hit 100mph a few times down the back straight.... which... was due to lack of passenger plus my roof was up.

Maybe your floormat was stuck under your gas pedal

Scot

 

[QUOTE]Originally posted by Scot
[B]My last session, I hit 100mph a few times down the back straight.... which...