There are two black inserts at the front of my Firehawk hood. I looked under the hood and saw that three plastic "bolts" and nuts hold this on. It appears that the piece that comes out is the black part and a part that is body color.

It appears that I remove this, the airflow could be improved across the front of the motor.

Has anyone removed this for tracking/road racing? Is there any reason that I wouldn't want to remove this? More underhood cooling = good. Especially with my car.

The only downside is much increased chance of rain/water ingestion if you still drive the car a lot. If you can choose another car when the forecast calls for rain then its a non-issue.

It looks easy enough to add and removed that I may try to run without them this weekend if it is dry. I have two road races and am always interesting in more cooling.

Take a look at where the opening is. It's just above the radiator which wouldn't help air flow through the radiator or from the engine compartment.

I wish it was that easy.

I thought we were talking Firehawk ram air hood. My bad.

like 94 bird said...with the stock hood the only thing that might be possible is to vent high pressure air as it exits the back of the radiator...C5R style. But odds are its not going to make much of a difference.

THeoretically it could keep pressure from building under the hood and causing lift at high speed.

Ah but Chris, venting pressure from under the hood will also help air flow through the radiator. I may very well modify my VFN glass hood to have some louvers in it before I install it.

...but wouldn't that draw more air from under the car and pull it past the radiator and my oil cooler? Also, couldn't it also serve as a vent?

Or is this my overactive imagination trying to lose a pound or two and hoping for a nice side-effect?

I don't see how it would draw any air in. There is plastic shrouding and a radiator just below it. If you drew any air in it would seem to me to be air that was bypassing your radiator by going up through your shrouding and out the hood vents - not a good thing.

AW crap! I meant to say Formula, not Firehawk.


...that's what happens when you are trying to sneak in a thread while the boss is wandering around...

... does that hood have heat extractors or some way for the air that is rushing in to escape? otherwise it's just going to lighten your cars front end.

Mike, no a LT1 Formula hood has no real heat extractors. It's ashame they did the "vents" the way they did. A foot or so rearward and we could have made use of them. They're just decoration where they are now.

Keith, how hot does your car run? I knew you had high oil temps, but I thought your coolant was pretty good. I'm installing an oil temp gauge finally and Monday I should be at Waterford Hills doing a little test. Trying to get the energy up this weekend to do a crude front breather setup for Monday.

I guess this was a dumb idea... Even so, I may run without the inserts if it doesn't rain.

Water temps run from 160-200. Oil temps from 200-280. My attitude is that anything I can do to increase cooling has to be a good thing.

Mike T. - I just got back from the track. I met you buddy with the CMC Mustang. I look forward to this weekend. There are a ton of AI/AIX/CMC cars coming. Most of the ones that I saw today didn't even show up on the entrants list on the NASA site... I wish you were here. Even if you weren't running.

Both of those temps are well within the good range. Even mineral based oil can take 280 deg. F for extended periods of time. With synthetic it's a piece of cake.

Your coolant temps are extraordinarily cool for a stock radiator car if you don't get over 200 deg. F. Have you raced in temps over 70 deg. F yet though?

I haven't raced in any event where it wasn't near or colder than freezing overnight. I also haven't run anywhere where I wasn't limited on how hard I could pound the car so I was always short-shifting (almost never above 5,000rpms). If it is dry this weekend, I will be pounding the car for the first time.

If 280 deg. isn't bad, why does my gauge peg at 300? Maybe I'm just stupid since I've never had a gauge before, but my logic has been that getting near max on a temperature gauge is probably bad...

To give you an idea one of the durability tests we do at work is to run our engine for 625 hours from peak TQ rpm to peak HP rpm with 230 deg. coolant and 290-300 deg. F oil temp. We run Mobil 1 0W40 and have absolutely no problems. The same durability schedule is used for other engines that use 5W20 mineral oil. They all have to pass before they are allowed into production.

Now, I'm not going to tell you to take a mineral based oil above 280 deg. F for long periods of time, but it wouldn't stress me at all to see 280 deg. F oil temp for hours on end, like in an enduro. Add synthetic to the mix and it shouldn't break down until 320 deg. F or slightly above.

However, the cooler you can get the oil (at least above 220 deg. F though) and the coolant (near 200 deg. F is good) the better your engine will like you.

Are you indicating engines w/the 160* stats (~180* track coolant temps) are running too cool?

Regards
steve

No, just estimates. It seems like most engines I see run 190-220 on a road course for sprint races. Nothing wrong with those kind of temps. If you can keep yours at 180 more power to you. Wouldn't go much cooler than that though. Engines do need some heat in them to work efficiently.

Well then, I guess I can hammer away with confidence today! I really, really hope it stays dry. Off to the track!

On two of three sessions, I completely buried the temperature gauge yesterday. I am returning to the theory (someone else's on this site) that the temperature sender is too close to the exhaust...

morning Keith

is the sender open to the exhaust or is there a thermal barrier between the sender and the headers?

How was Beaver Run on Saturday anyway?

I don't know, for the exhaust to heat up the sensor enough for it to give false readings it would have to be damn near touching it. From this picture: http://community.webshots.com/s/image9/9/3...09mLtiIC_ph.jpg I don't see any exhaust anywhere near the sensor. The sensor is in the pan, submerged in oil. If the exhaust is heating it up, I'd say it's heating up the oil in the pan and the sensor's reading is accurate.

I'm sticking with the theory that you need to dump that RV Tranny Cooler thing and put in a stacked plate oil cooler, one designed to cool the engine oil on racecars, one that's many times more efficient. This is a theory that can be tested. You're measuring the oil at its hottest point. It looks like your guage is electric, if you install a sender to give you after cooler temps with a switch you can see exactly how much or how little the cooler is doing.

Keith, I'm with Jon. I'd put some thermal barrier on the wiring since you don't have steel braided sheathing on the wiring, but that would only be to protect it from melting. The picture doesn't show it but I'm guessing the wiring gets pretty close to some primary pipes as it goes up and towards your firewall.

Anyway, I don't think you exhaust is heating up the sender. Jon's suggestion is good to see how much temperature drop you're getting through the cooler.

I'm finishing up my front breather work today (wahoo!) and should be testing tomorrow. If it drops my temps I'll take some pictures and send them to you. It's a lot of time consuming detail work but it's not hard to do at all and seeing the radiator/oil cooler right through the fascia tells me I'll be getting a LOT more air.

Well, I buried the oil temp in all three sessions today. I suppose I should look into a better cooler...

Mike - Beaver Run was wet yesterday. In the practice session, the line dried out. In qualifying, it was very wet. In the race, it started wet and began to dry by the end of the race. Today, it was warm and clear all 3 sessions.

We had 37 (!) cars in our run group. That's alot of cars. In the Big Bore group for the weekend, there was only one accident - a single car ooops today from a newly licensed CMC driver. He apparently dropped 2 wheels off, over-corrected, shot across the track and slammed head-on into the armco... I didn't see it, but I was lapping when I came around and saw the car. The driver was shaken, but OK, but the car was destroyed. With all of that tight racing, everyone was very careful. I've never run like I did this weekend and I find it absolutely amazing that we get through these races without incident.

Here's a good one - during the warmup lap for the Hona Challenge race, the polesitter crashed into the armco while scrubbing his tires. The car is pretty messed up. I'm sorry - that's funny to me.

So, all this race talk and no comments about how you did? Are you writing a long post about the race weekend and just want to make sure you catch everything before you post it?

I have been keeping a written diary of my events for my own purposes. I can post writeups if you guys are interested. I am just hesitant to do this because some people are so beyond my experience that they may find it to be drivel... Do you want to see an account of this weekend? I haven't written this weekend's entry, but leave for a business trip to Canada today and may write some things during my travel time.

In brief, I finished ahead of the other rookie points contender both days. He and I paddocked together and we have agreed to set our goals by gauging each other - and we look for each other on the track to run together. On Saturday, it was due to better driving. On Sunday, he was significantly quicker than me (I shouldn't have advised him on his approach!) but had a clutch problem on the 8th lap and pulled off the track. My personal goal was to simply run a 1:09, but I could only get 1:10's faily consistently (In the race, Griswold ran 1:01's!!!).

They weighed me and my car yesterday - 3553!!!! at a whopping 287 rwhp. The other rookie has 330rwhp and is near the limit on weight within the rules - he runs 110 octane gas! Actually, I am pretty happy with my lap times considering how porky my setup is. The other rookie and the VVC driver that I hang out with are buying me "oink oink" stickers for my car.

Tuesday my oil temps topped 300 once but usually stayed in the 285-295 range. That's with the sender in the location above the filter which should give cooler temps than where you have yours.

That's without an oil cooler, water temps stayed at about 190-195. It was a hot day--I think probably the hottest day I've ever ran PR--temp was about 80 and the sun beat down all day heating the track surface up to 115 or so.

One other note, this was the first time I was seeing decent oil pressure at those temps (around 60 psi instead of 45) at WOT. I gave Mobil 1 15W-50 a try. I don't know if that did me any good other than making me feel better, but it sure did make me feel better....