3.5 days and 1,600 miles in a 7

[dhubbard422]

Central Texas does have some nice roads. I had planned to do The Twisted Sisters on the way home, but I made an executive decision on day 4 to just make a bee-line for home. I plan to find time to do the Twisted Sisters in November...

 

http://www.motorcycleroads.com/75/555/Texas/The-Three-Sisters-(AKA-The-Twisted-Sisters)--Ranch-Roads-335-336337a.html

[Klasik-69]

All, Thanks for the great comments and suggestions! I'm looking forward to fettling my 7. Also looking forward to the first autocross. However, it may be a few weeks before I can give the car much attention as I also help organize a vintage motorcycle rally (and trials event) for charity and it's rally time! http://www.harvestclassic.org

 

Thanks again,

Don

 

When it comes to autoX, be careful not to suck up a cone with one of the rear wheels while using tires like the Hoosier A6 or similar compound. It will get stuck to the tire, wrap around and fling the rear wing right off the car. It also rips out the riv-nuts out of the aluminum if yours uses them (not sure on your car). I learned the hard way, slung mine up about 15 feet in the air, then spent about two weeks repairing it and the body. Anyway, you're not supposed to run over cones. Nobody told me, I thought it was like bowling, the more your got, the higher the score. Well, I was right about the high score.:ack:

[MHKflyer52]

Anyway, you're not supposed to run over cones. Nobody told me, I thought it was like bowling, the more your got, the higher the score. Well, I was right about the high score.:ack:

 

Now that made my day and has me laughing and one of the reasons I built my rear fenders the way I did as seen in this photo.

:driving:

[yellowss7]

You mean like this? :willy_nilly: I'd highly recommend using nylon bolts to hold the rear wings on and you don't need more than 5 or 6. That way when you hit a cone you DON'T rip out the rivnuts and tear up the aluminum skin. You Will have some fiberglass work to do but that's not a hard job. That wing has been repaired twice and looks fine.

http://usa7s.com/vb/attachment.php?attachmentid=1853&stc=1&thumb=1&d=1276827644

Edited October 11, 2013 by yellowss7

[TomF]

I've also heard of people using industrial-strength velcro to hold the fenders on.

[DaveD]

Don,

 

I enjoyed your narrative on the trip. Some day I hope I can do something like this with my car.

 

To any of you that own an S1 and are experiencing the issue with the car acting like it is starving for fuel and quiting need to do a couple of things. I chased this problem for 5 years and finally got it figured out this year.

 

First you will find that in the fuse box, on the firewall, the fuel pump fuse is the middle fuse in a chain of 5 fuses being supplied with what looked like 2 wires. One wire at the top fuse and the other at the bottom fuse. When I removed the fuse box and found the insulation gone on the wires chained together, I rewired the box so each fuse had it's own supply wire. Obviously at some point these wires got very hot which would lower the voltage to the fuel pump.

 

Second, my car was getting air into the fuel line prior to the fuel pump. This is what causes the fuel pump to get noisy. I tried taking the in-line filter out, but air continued to get into the line. I had the tank off the car multiple times tightening and checking the clamps inside the tank. To no avail however, as air was still getting into the line somehow. After reading through the installation and service manual I ran across the recommendation that the fuel be taken from the bottom of the tank, not run out the top and not to use an in-line filter. Only use an in-tank screen. I finally bit the bullet and installed a bulkhead fitting in the bottom of the tank and ran the fuel line directly to the fuel pump. After 5 years PROBLEM SOLVED.

 

I had my car at NJMP this summer for it's 5th and 6th track day in 4 years. It was the first time I made it through the day with out the fuel issue causing problems. I did find out however that when the tank gets below 5 gallons the long fast right hand corner before the slow left hand turn on Lightning would cause enough fuel to run out of the sump that the fuel line would pick up air. I had to make sure I started each session out with a full tank (which is only 9 gallons). I found that pushing my car hard I was using 5 gallons of gas in a 30 minute session.

 

I don't know how the Caterhams and other cars are with heat. The S1 is very hot in the engine bay. I don't believe the Caterhams and other cars have the engine enclosed like the S1. I found my oil temp getting to 150 degrees C even with the oil cooler on it. The regulator in my alternator quit during the track weekend. Probably due to the heat. This is the second alternator to go on the car. The Caterhams all have lots of venting in the engine bonnets. Plus they do not have a pan enclosing the bottom of the engine compartment. My car has two cowl induction type scoops on the hood, but I don't think it is anywhere near enough to allow enough air to flow through the engine compartment. The rule of thumb for cooling in an airplane is to have 2.5 times the exit openning as intake openning for proper cooling. I know my car is no where near that. I am planning on coming up with another bonnet with the venting similar to what the Caterhams use. Also, the comment about the open space around the radiator is a good one to address. I plan to use silicone, as used on airplanes, to close off the openings and force all the intake air coming in the nose through the oil and coolant radiators.

 

Dave

[dhubbard422]

Dave,

 

Thanks for the suggestions!! I will check the wiring. I will also look at the fuel pickup. I also want to find a good solution to monitoring the fuel pressure.

 

The heat coming off the trans tunnel is quite high in my 7 (as Klasik has said - it's an oven!). I wonder if the belly pan needs some venting... maybe an adjustable NACA duct? I was planning to do a quick test and just see if the temps coming off of the trans tunnel are lower when running without the belly pan.

 

Tom and I also discussed the fact that most 7s seem to have considerable venting on the bonnet. Maybe the Superformance needs a vented hood. Again a quick test would be to run without the hood and see if the temp inside the car is lower.

 

Thanks again for the suggestions,

Don

[dhubbard422]

When it comes to autoX, be careful not to suck up a cone with one of the rear wheels .... Anyway, you're not supposed to run over cones. Nobody told me, I thought it was like bowling, the more your got, the higher the score. Well, I was right about the high score.:ack:

 

Bowling for cones! Gotta' love it. :rofl:

 

Yeah, I've wondered how the fenders on the S-1 will fare against a cone at speed. I've considered making a set of molds, before I whack a fender, but I have to admit that I'm lazy. I've also done this type of work before and know that I don't really want to build the molds. Building some light, yet super strong carbon-kevlar fenders might be interesting though... Oh well, if/when I whack one and have to repair it, maybe I'll get inspired to build some molds or find someone with a chopper gun to build the molds for me.

[TurboWood]

Maybe this is a newb question, but why go to all the effort to make the rear fenders easy to breakaway instead of just removing them? Is it just looks or is there a functional reason to keep them on?

 

Daniel

[yellowss7]

SCCA regs for Autoxing, require that you have at least half of the tire covered with a fender, if I recall correctly.

 

Tom

[coffee break]

SCCA regs for Autoxing, require that you have at least half of the tire covered with a fender, if I recall correctly.

 

Tom

 

Inside, top, front or back?

[yellowss7]

sorry, I believe it specified half the width of the tire had to be covered.

 

Tom

[S1-MEAD]

Hello All,

 

I've just joined the forum but have been checking in every few months for many years.

I own a Superformance S1 and have been enjoying it for 5+ years. The car is as well built and as reliable as my modern. However, I have experienced the fuel starvation issue combined with a hot and noisy fuel pump, I tracked the problem down to a faulty fuel pressure regulatior which I replaced with a new one purchased from Burton Power. Never had a problem since.

As for the overheating, not an issue I have experienced - I know there is a service bulletin (0201st) detailing a lower temp themostat and thermo switch for the fan, my car had this done and in fact may be the one pictured in the manual.

 

I have all this information electronically - Owners Manual (16.5MB) and Service Bulletin (11.5MB).

[yellowss7]

Welcome aboard! Hopefully you can come out to NJMP next June to join the fun. I have it on good authority that we may have TWO S1's out on the track next year. Right Steve??? :jester:

 

We are in the planning stages right now but we hope to offer Non trackday activities to those who would like to get together but not put their car on track. Stay tuned. So is your call Metallic Orange like DaveD and S1Steve's??? That would be a hoot.

Tom

[Croc]

I own a Superformance S1 and have been enjoying it for 5+ years.

 

HI S1-Mead

Did I meet you out at the Carlisle Show about 4 years ago? Your green S1 is jogging a memory in this rusty brain of mine!

Cheers

mike

[Off Road SHO]

I am going to attempt to track down this heating problem in a logical way, by doing one modification at a time. First, close up all the air by-passes around the radiator. Second, remove the hood and go for a drive to see if it needs more exit area. Third, install a 160 thermostat, and fourth install a lower temp fan switch. I will report back at every step. But I will start a new thread.

 

Tom

[xcarguy]

Tom,

 

I may have missed it, but have you added a 'water wetter' to your coolant?

[Automoda]

You know I'm not totally sure that closing off the space around the radiator is going to help. I know modern cars have a lot of plastic that looks like it is funelling air into the radiator, but I've read some stuff that makes me think that its not doing what one would assume its doing.

 

In another forum someone posted an article by a guy that was trained in fluid dynamics/aerodynamics. The discussion was about all these "Ram Air" and "Cowl induction" hood scoops. The guy basically said that you cant 'shove' air into an opening via scooping until you reach about 460mph. Apparently gasses do not behave in an intuitive way. The article stated that it doesnt matter how the scoop is oriented in relation to the air flow until you start hitting that critical speed. In short, scoops are for looks since you could just have a hole, or the scoop could face backwards or sideways or whatever.

 

That leads me to believe that as long as the radiator is more or less directly behind the nose opening, you're going to get enough air. Blocking off the space around it may or may not do anything (Other than reduce the flow of cool air into the engine bay), but I would think the fan is more of an issue. My Birkin had no shroud around the fan as it came from the factory, and the fan sat a few inches behind the radiator surface. I built a fiberglass shroud for it (which fits everything snugly) and now I have zero overheating problems (And some air definitely can get around the sides of the radiator).

 

http://herb.linkrealms.com/lotus/fan_side_a.jpg

 

Id think the fan should be able to run enough air to cool the engine even while driving around (perhaps not racing though).

 

Anyhow I'm no expert but I'm just saying that blocking off the sides of the radiator is probably not going to end up being the real cause of your troubles.

[Off Road SHO]

Automoda,

I agree with the shroud, except it is getting to 220 degrees before the fan even turns on, which leads me to assume that there is not enough airflow "through" the radiator. (my fan is mounted right to the radiator. I believe that the reason there isn't is due to the difference in air pressure in front of and behind the radiator fins. That is the function of all those plastic pieces you mentioned and that little air dam thingy, it builds up an area of positive air pressure in front of the radiator and a negative area behind the radiator and below the engine. Like in your shroud example, there must be a positive pressure differential front to back. The gaps around the radiator and the (almost) sealed up bottom of the car causes there to be a neutral differential, that is, the pressure right in front of the fins is near equal to the pressure right behind the fins. Whenever the pressures are equal, there is no air movement through the fins, which is of course how a car's radiator works, moving air across moving coolant. There is still plenty of air movement around the radiator though.

 

I have not tried water wetting agents for two reasons: One, a modern day radiator, sized appropriately for the amount of heat that needs to be removed, is way efficient, hence the reasons to have something that keeps the radiator from getting all the coolant that the water pump pumps, the thermostat. Two, water wetting agents were invented to get the absolute most heat transfer ability out of the least amount of coolant and smallest radiator. This saves weight, which in racing is paramount only to HP. If our cars were at that stage, we should all be looking for the absolute lightest wheels, tires, racing suits, and by extrapolation, lunches. I am not anywhere near that level, though I would never presume to deny anyone else that option.

 

When I first got to see this S-1 and it was the first S-1 I had ever seen, the first big red flag that went up in my mind was, "oh boy, I wonder if there will be enough air flow with all that bottom shrouding.

 

We shall see.

 

Tom

[Off Road SHO]

Automoda, About the ram air effect, your air/fluid dynamics guy was mostly right, no matter how big of a ram air (facing forward) scoop you have, in most cars it doesn't provide a positive benefit until you are into triple digit speeds and then it has less effect than just removing the outside rear view mirrors.

 

However, the rear facing cowl induction hoods found on a lot of GM products, where the opening in near the windshield, does in fact derive some positive air pressure after 35-40 mph is attained. This is because the windshield is sort of acting like an air dam. I did a lot of yarn on a fishing line tests (before someone gave me a nice smoke generator) that helped me understand how fluids flow around stationary objects.

 

Tom