New to FF, Newb Question

[crit]

Hi ApexSpeed forum members! First post from me. I am looking at getting a FF for AutoX and have a few questions regarding car setup for AutoX.

1. Does anyone use an alternator? If not, how long does the battery last to power the car with the multiple starts and stops between runs?

2. Does anyone use electric cooling fans on the radiators as airflow in autoX isn't that great.

3. What are some favorite tires for autoX as they don't heat up as quickly as the track tires.

Thanks all and excited to soon be a FF driver!

-Crit

[fitfan]

i have a couple sets of used hoosier autoX FF tires if your interested in San diego area. they came of my FF that i converted from autoX to road race.(they are a much softer compound) R25B, FF slicks.

[crit]

PM Sent! Thanks FitFan

[DK540]

To chime in with FitFan's offering, I just bought a gearbox from an AutoX FF, which I am putting in a road racer, and want to sell the fixed first gear layshaft and the two low ratio gearsets I'll never use -- 14/36 & 17/34. Interested? THESE ARE ALL SOLD, thanks.

David

[-pru-]

Crit,

A few answers...

1. Does anyone use an alternator? If not, how long does the battery last to power the car with the multiple starts and stops between runs?

Those using the Honda Fit, an alternator is part of the engine package.

For those using the Ford Kent, all that is needed is a good, fully charged battery for a full day for running (multiple drivers and multiple starts). If running a multiday event, recharging the battery between days is recommended.

2. Does anyone use electric cooling fans on the radiators as airflow in autoX isn't that great.

I do not have any experience with cooling fans, so I cannot offer any comments.

What I have found is that if you have a robust cooling system and are smart about running the car during hot days, it's not necessary. That is, since switching from OEM brass to aluminum radiator as well as running with a thermostat, I have not had any issues.

When the car does get hot (i.e. over 200 degF sitting in grid without engine running), simply spraying the radiator down with water (via a garden sprayer) makes things manageable. If you're at the point of spraying down the radiator(s), you need to be more diligent about running/idling the car prior to making a run (i.e. tell the grid workers "I want to go directly to the start line").

3. What are some favorite tires for autoX as they don't heat up as quickly as the track tires.

The Hoosier R25 has become the default CM tire. Avon does offer some soft compound FF tires, but I do not have any experience with these tires.

Take care,

[crit]

Thanks for offering the gears David, however the car is already setup for autoX with a very similar setup.

Chris, thanks for the answers! One more question, where can I purchase R25 Hoosiers as tire rack only has A7s? Thanks!

[Barry Ott]

Crit,
Welcome to CM! You're lucky to have several CM cars to run with! I added a little to Pru's answers below

Crit,


For those using the Ford Kent, all that is needed is a good, fully charged battery for a full day for running (multiple drivers and multiple starts). If running a multiday event, recharging the battery between days is recommended.

External jumper batteries are pretty common to. They can give you extra margin when you're doing a lot of engine starts or allow you to run a smaller on board battery if you need to drop weight


What I have found is that if you have a robust cooling system and are smart about running the car during hot days, it's not necessary. That is, since switching from OEM brass to aluminum radiator as well as running with a thermostat, I have not had any issues.

Running water only (with an additive for corrosion prevention and lubrication) cools much better than the typical 50/50 mix in a street car. My car was marginal with 50/50 mix and now I struggle to keep heat in the car if it's not a nice warm day. You probably wouldn't need to worry about the water freezing in San Jose :-)

[Barry Ott]

Thanks for offering the gears David, however the car is already setup for autoX with a very similar setup.

Chris, thanks for the answers! One more question, where can I purchase R25 Hoosiers as tire rack only has A7s? Thanks!

Maybe these guys would be convenient for you?

https://www.hoosiertirewest.com/

I get mine from R&S racing:

https://www.rsracing.com/

Ron and Sonia are Autocrossers and have always been very helpful and knowledgeable!

Barry

[-pru-]

Running water only (with an additive for corrosion prevention and lubrication) cools much better than the typical 50/50 mix in a street car. My car was marginal with 50/50 mix and now I struggle to keep heat in the car if it's not a nice warm day. You probably wouldn't need to worry about the water freezing in San Jose :-)

Thanks for the input Barry! Good point on straight water only with additive; I run water with RedLine Water Wetter :

[Jim Garry]

I always had a cooling fan on my autocross FF. Never had any issues with it drawing too much electrical power. I highly recommend it if you will be running in a hot location. It removes a lot of potential anxiety.

[PDM075]

Crit

Also new to CMod last year, and changed my battery to a Battery Tender lithium 2.1 lb race battery and it starts and runs all day long with no need to run a jumper battery. (my car came wired with a quick disconnect and I carry a large jumper unit just in case - but never found a need last year during multiple runs (8+ during a day) to have to jump start the car.

Chris summed it up - pretty much spec tire is the consensus nationwide so far in the Hoosier. (although Ben has been testing the Avon's...so he can chime in on his results thus far.)

Good to see more West Coast Fords.....as Charlie, myself, Ben all picked up cars last year....hopefully you, AND....another PNW car that will likely be announced very soon


(....I'm predicting a big meetup in the near future of all the Cali, Oregon, WA, Idaho and B.C. cars......)

don

[ewcmr2]

Crows landing Pro was over 100* last year. With multiple drivers I was glad to have an alternator and radiator fan. Most events the fan doesn't need to run but it's nice to have. Having them means I don't have any worriy about managing temps.

[CM/FFdriver]

Hey Crit,

I also live in San Jose maybe we can talk some time.

I don't run a fan and do plan on an alternator in the near furture.

I've been running the R35 and have been very happy with them, we will have to talk about that.

Alignment is up to the way you drive and that discussion will be a long one but with up to 25 event next year, you will get lots of seat time.

Ben

[TeamFRD]

Seen this? http://apexspeed.com/forums/showthread.php?t=61052

[mwizard]

I have a fan which came out of a motorcycle. With 2 drivers we sometimes use it or spray the radiators. If I am by myself I tell the grid person that I am like a shark and need to keep moving. Battery is not usually a problem, but when there are 2 of us or for cold starts, I use a jumper battery to be safe. Alternators use some of the minimal ava power, so not usually included. There are several local Hoosier dealers. I use ADDS Wheels in Sunnyvale. Barry is an autoxer. 408-744-9433. One other thing no one told me is that FFs need some lead in their gas. I mix 50/50 with leaded race gas.
Mark

[crit]

Thanks for all the responses! Ben mentioned he runs race Gas when I talked to him on the phone. Anyone run AvGas 100 low lead? I use to fly out of RHV and know the FBO that sells the fuel so can get that stuff for pretty cheap. Ben mentioned the tuning of the carb might have to Change if I run the AvGas due to the fact that the fuel was designed to combust at a higher elevation. Anyone else have experience with AvGas?

[DanW]

Thanks for all the responses! Ben mentioned he runs race Gas when I talked to him on the phone. Anyone run AvGas 100 low lead? I use to fly out of RHV and know the FBO that sells the fuel so can get that stuff for pretty cheap. Ben mentioned the tuning of the carb might have to Change if I run the AvGas due to the fact that the fuel was designed to combust at a higher elevation. Anyone else have experience with AvGas?

Yes, you can run avgas. It's not the optimum fuel, but its acceptable. Jetting with EGT probes on the dyno, setting the optimum ignition timing is the way to go. Its hard to get accurate lambda with an O2 sensor if the header has any leak whatsoever.

The savings on fuel for autocross is minimal. Doubtful you would use more than a gallon per event.

Suggest not using any fuel with ethanol in it, both for storage stability and power.

I plan to autocross some this season as well.

Regards,
Dan

[CM/FFdriver]

I plan to autocross some this season as well.

Regards,
Dan

That would great to See Dan

Ben

[EYERACE]

Distilled water, 1/4 bottle Water Wetter and a 1/2 can of water pump lubricant [getting hard to find]...........no antifreeze.........when it's cold put 100 watt light bulbs near engine..........but what do I know about seriously cold weather - I live in Orlando

show up with your battery fully charged.......get a solar powered charger and put it on the battery at the event every chance you get.........you don't need an alternator

plan A........fire up the engine in the paddock and get it up to temp.........shut it off........push the car up to the start......refire when you're ready to make your run.

plan B......only fire up when you need to.........get your buddy to tow you with an ATV / golf cart / scooter or cycle / or some other suitable tow vehicle any other time.

as your tires will never really come up to track type temps you may need to bump up your tire pressures a little higher than road racing guys use

AV gas will do just fine...........you get more power from the lowest octane fuel you can use that does not ping........higher octane burns hotter

make sure your flywheel is a light as is legal

[DanW]

AV gas will do just fine...........you get more power from the lowest octane fuel you can use that does not ping........higher octane burns hotter

Stan,
Exactly. But 1365F EGT is near optimum, 1400 moves aluminum...

[chrisw52]

Thanks for offering the gears David, however the car is already setup for autoX with a very similar setup.

Chris, thanks for the answers! One more question, where can I purchase R25 Hoosiers as tire rack only has A7s? Thanks!

crit, welcome to the ever growing CM group in the SF bay area!

You best place to buy race tires is locally in Hayward from Roger Kraus racing. http://rogerkrausracing.com He can get you any type of hoosier or Avon tires for the formula ford.

If you need technical assistance, one of the more reputable shops in the region is porterRacing out in merced.

[crit]

Ben also mentioned Porter Racing for corner balance and alignment. Sounds like a great shop!

[Barry Ott]

Hey Crit,
As you're seeing, there's not shortage of great advice :-) My 2 cents on cooling and starting is pretty simple, just take the car out and see what it does. Make sure the on board battery is fully charged and the cooling system is in good working order before you go to the event, and then just go see what it does. Bring a jumper battery as a precaution to start the car if needed, it will probably *run* fine if it doesn't have enough power to *start*. I'd be really surprised if the car ran hot this time of year. From there, you can see how it works and address issues as needed. I think you'll find that driving a CM car isn't that much different than driving a street car, just faster and more fun :-)

Good luck!
Barry Ott
95 VD/Honda and ex-'88 Reynard/Kent

[TimH]

Why we use it:

The car can sit for months and I don't get shellac in my carb.

And Ivey tunes his motors with it.

[CM/FFdriver]

Why we use it:

The car can sit for months and I don't get shellac in my carb.

And Ivey tunes his motors with it.

Ok good to know, will be calling Ivey for tuning spec's.

Ben

[EYERACE]

point about the higher octane................if you're not pinging with a lower octane fuel, you get no extra power from the higher octane fuel........you simply have a hotter combustion.

[CM/FFdriver]

point about the higher octane................if you're not pinging with a lower octane fuel, you get no extra power from the higher octane fuel........you simply have a hotter combustion.

EYERACE,

What I have heard is that different octane fuels burn differently and need to adjust timing for that so you can take advantage of the higher octane, please enlighten me about this so maybe I could save some money.
What is the octane for AV fuel and if AV fuel stores better that would be a good thing right?

Ben

[DanW]

An explanation of avgas octane and comparison with auto fuels. The actual functional differences are small as long as you have sufficient octane.

Good idea to consult Jay Ivey for the straight scoop for using avgas in your engine. He can likely tell you what fuel he used to test it on the dyno.

http://www.aviationpros.com/article/...togas-vs-avgas

[beachguy12]

crit, welcome to the ever growing CM group in the SF bay area!

You best place to buy race tires is locally in Hayward from Roger Kraus racing. http://rogerkrausracing.com He can get you any type of hoosier or Avon tires for the formula ford.

If you need technical assistance, one of the more reputable shops in the region is porterRacing out in merced.

Agree. Roger Kraus is the guy to go to. I've known him since he first opened his shop in the70's. He is where to go and he is just a few mikes away.

[CM/FFdriver]

An explanation of avgas octane and comparison with auto fuels. The actual functional differences are small as long as you have sufficient octane.

Good idea to consult Jay Ivey for the straight scoop for using avgas in your engine. He can likely tell you what fuel he used to test it on the dyno.

http://www.aviationpros.com/article/...togas-vs-avgas

Very cool read, I will be calling Jay Monday morning about what gas to use because of EYERACE and DanW input. It's very interesting stuff and will call my fuel guy about leaded fuels with a lower octane so I can match my engine with the fuel to get the best performance.
This is really good because I'm going to the Dyno sometime in March and still have 3 gals of 110 first and then go to AV gas and work from there with maybe other octanes to Max out engine performance.
The Great thing about Apexspeed is the info given out and because I love trying different things in engine performance, shifting points, some handling ideals, finding parts has been Great!!! Thank you Apexspeed and it's people!!

Ben

[chrisw52]

Thanks for offering the gears David, however the car is already setup for autoX with a very similar setup.

Chris, thanks for the answers! One more question, where can I purchase R25 Hoosiers as tire rack only has A7s? Thanks!

crit

what kind of car did you get? post some photos!

[crit]

Hi Chris, I put a deposit on a T342 Lola and go to inspect and purchase a week from today! Wish me luck!

[fitfan]

we all run AV gas in our ivey engines around here. he builds my engines, "clutch to carb".

[crit]

FitFan, do you know the jet sizing used in the carbs tuned for AvGas?

[crit]

When I inspect the car I am going to do a compression check but I am not sure what would be acceptable numbers for the Kent 1600. What numbers have people been using, cold or warm?

Also, I'm assuming it's done like any other compression test, plugs removed in other 3 cylinders not being tested, WOT with clutch disengaged. Correct me if it's done differently.

Thanks!!

[chrisw52]

a more important test would be a leak down test @ 100psi on a warm engine. You should not have more than 3% leakage across all 4 cylinders.

On the compression check, I don't recall what good solid compression rates are, but they should be with 10% of each other. Pay attention to how quickly the cylinder builds compression. When I test my car, I get 95-100 psi on the first crank, then incremental changes to their maximum values.

If you haven't already, checkout this website http://www.thekentlives.com
It has a lot of good info on what to look for when buying a car.

[TimH]

Hey crit,

The FF community is a pretty small one. The odds are good that the car you're looking at is well known to veterans in the area.

Not that you shouldn't do your own due diligence, but just sayin'..

[EYERACE]

I've never heard of anything BUT 100 octane Low Lead AV gas

[DanW]

When I inspect the car I am going to do a compression check but I am not sure what would be acceptable numbers for the Kent 1600. What numbers have people been using, cold or warm?

Also, I'm assuming it's done like any other compression test, plugs removed in other 3 cylinders not being tested, WOT with clutch disengaged. Correct me if it's done differently.

Thanks!!

Chris,
The info on the leakdown test is a good rule of thumb, but compressed air is not always available.

Compression numbers for a warmed up motor should be within 5-10% of each other. Engine warm, expect 185 to 165 as ring tension and therefore ring sealing at low pressure will vary. Even if the compression is a bit low, it could be low tension rings that seal just fine at speed and load. Ask how many events since the last rebuild. Most events put 2 to 2-1/2 hours on the engine at speed. Ask if the crank is cast iron or cast steel. The newer cast steel cranks are preferable, but a well prepared cast crank is just fine. Good luck.

Regards,
Dan

[CM/FFdriver]

Am I asking to soon, did you find a car yet Crit?

Ben