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Kirkham Motorsports

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  #81 (permalink)  
Old 01-22-2014, 05:07 PM
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ERA is sending out a new blank dash we will for sure paint it. I did not paint any exposed wires, just loom. Pictures are with flash -

Great idea -

x-chr
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  #82 (permalink)  
Old 01-22-2014, 05:32 PM
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Quote:
Originally Posted by ERA2076 View Post
-

Great idea -

x-chr
---so is replacing every sheet metal screw ERA supplied with riv-nuts and stainless button headed machine screws.
But you knew that...
Hey-can I get an honorary team tee shirt??
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  #83 (permalink)  
Old 01-22-2014, 10:58 PM
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We've been working on that (ERA fasteners for buttons) as it comes. Not on a hunt - anything we touch we convert. If there is more in that area, we may get it. If it is pulling from building - no. It's like scrubbing aluminum, you can spend a lot of time doing it. Overtime we will get it.

I don't use serts on everything. I have been working on ducting the radiator and there I tap the sheet and screw it together with 10- 32(?) button heads. There is a fair amount of fastener conversion involved with the Cooling and adjacent panels.



chr
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  #84 (permalink)  
Old 01-23-2014, 10:49 AM
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I've had some troubles with riv-nuts in aluminum panels, such as for the transmission tunnel to floor. Not sure if it's just some cheap riv-nuts or what. It took me about 3 times in and out with the tunnel before I finally had it fastened down. I kept having riv-nut inserts break off and I think I have one bad one now I'll have to replace the next time it's off. Kind of wished I had stuck with screws as I would have had it on in 20 minutes instead of 1-1/2 hours.
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  #85 (permalink)  
Old 01-23-2014, 11:44 AM
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If it is pulling from building - no.

chr
So no crew member shirt for me??
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  #86 (permalink)  
Old 01-23-2014, 11:47 AM
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Kind of wished I had stuck with screws as I would have had it on in 20 minutes instead of 1-1/2 hours.
I had no problems with the Marson tool and their inserts. Did the brake access panel, tunnel and all the tin in the nose. Made maintenance removal a snap and solid attachments.
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  #87 (permalink)  
Old 01-23-2014, 01:48 PM
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Quote:
Originally Posted by ERA Chas View Post
I had no problems with the Marson tool and their inserts. Did the brake access panel, tunnel and all the tin in the nose. Made maintenance removal a snap and solid attachments.
I don't remember what mine is - got it from Summit Racing I believe. But I think I ordered some additional riv-nuts through McMasters. I've used them in several places. The trans tunnel just turned out to be a headache.
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  #88 (permalink)  
Old 01-23-2014, 05:11 PM
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So no crew member shirt for me??
The paint cost you - sorry.
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  #89 (permalink)  
Old 01-23-2014, 08:00 PM
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I've been wanting to share my aero thoughts for a while, but I got bogged down. My car should be capable of red line in 4th gear and I for some strange reason have the desire to try to get it to do it.

I am a big Carrol Smith fan he would say if it does not work or you cannot make it work, get rid of it. I am also a Richard Hugins fan and have spent considerable time reading his contributions on CC. IMHO - JBL build's a bad ass Cobra, but not my cup of tea.

I can never stop wondering about some ground effects on an ERA because the chassis is so setup for it. I purchased a book by Simon McBeath and as I started to study the problem it became apparent the air must be controlled thru the car as well as around the car so I have been working on ducting the radiator and closing off the front of the car. That sent me back to Mr. Smiths work.

There is a chapter in "Tune to Win" dedicated to internal areo and cooling. One of the physical limitations to air flowing over a surface is that it will detach from the surface and become turbulent if the angle of the surface is falling away to steep to the natural direction of the air flow. Smith quotes 8 to 15 degrees.

Here we see the cooling of a nicely built FIA

Stuff:

1) The air cannot and will not follow the profile of the shroud thus filling that lower area with very turbulent air.

2) The shroud is daming the air on the backside of the cooler and then releasing it into the lower radiator region from the sides which adds to our turbulence in front of the radiator and drag.

3) Also notice the dams on either side of the radiator that are for all practical purposes perpendicular to the air flow. Smith states that a surface normal to flow represents a drag coefficient of 1.5 (the highest). There are around 346 in^2 of radiator area. There are an additional 90 in^2 of side panels which do nothing and the domed roof only adds to the problem.

5) There are a lot of threads on "How do I get cold air in the foot boxes?"
Notice the fresh air inlets and consider - is it is possible that the air filling below the radiator shroud is causing a mess with the whole thing since what we want is smooth laminar flow. One would assume the air would be laminar feeding the fresh air, but that is all it would be. That mess could well interfere with feeding the fresh air ducts, I only throw that out as a point of interest as the fix I would use for that I am instead going to use to feed the brake ducts.



So now I want you to look at my direction.

The stock oil cooler that came in my car is taller than the opening in the body. I went with a 3." Setrab and moved the mounting outboard. We want clean straight air going thru the cooler. By moving the cooler outboard I hope to use the cooler to help move excess air away and around the front of the car. I will add side dams to stop air bypassing the cooler. Notice the cooler is below the top of the glass.



We are looking from the top down at the lower radiator support. The foriegn sheet metal is the top of my oil cooler shroud. It goes from the top of the cooler to the bottom of the radiator shroud and exits between the bottom of the shroud and the fiberglass



Here is the exit of the oil cooler duct. The walls just need a small extension to fully box it to the exit.


I have prototype walls built to box the radiator and I have added a false roof to the dome to decrease that volume in that region. We will box the hinges so air does not leak thru there.



I am going to fill the the ellipses in the nose with aluminum panels that intersect the oil cooler opening in the fiberglass and mount the brakes ducts in those panels.

We still have the problem of the intake opening not aligning with the bottom of the radiator. My plan is to add a floor from the fiberglass intake shelf to the bottom of the radiator. Add some kind of small riser and then add a roof on top of the riser that slopes back to the radiator at 8 degrees.

This will split the radiator cooling into 2 intake tracts. A large one which gets straight flow and a lower, much smaller (7 rows) that gets air, perhaps not so clean, but it will not mess with the air in the larger tract.

I plan to fill the center section with 44% area reduced screen (Pegasus #10 screen). If it won't stay cool (it will) I will keep using bigger screen until it does or I will not run with any screen. It may be we have to run different screen depending on variables.

I want to use the screen to help move air around the car. I can't even mess with external aero until I get this as they both go together.

I plan to sheet the bottom - the wood is in the same plane as the frame. The front attachment is above the oil cooler exit (same plane as lower radiator shroud) and then slopes towards the wood. We will bend it at the bottom of the wood and attach to the cross member. I hope to use this to help with down force and also pull exit air from exchangers.



In "Tune to Win" Smith talks about the ducts acting as diffusers. By reducing the frontal intake tract we can build a good diffuser to feed the radiator and not pack the nose with air. I have plans to duct the exit of the radiator also but that is for another time.

If you have thoughts or experience please share.

x-chr
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  #90 (permalink)  
Old 01-24-2014, 03:58 AM
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I've wondered if aerodynamically the oil cooler wouldn't have been better mounted in front of the radiator on race cars with the lower duct opening left open or ducted to brakes, etc. I wouldn't think on a track car that didn't spend any appreciable time lugging around at low speeds, that it would cause any cooling problems. I could be wrong.

This is an interesting project. Very entertaining to follow.
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  #91 (permalink)  
Old 01-24-2014, 06:26 AM
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I read Smith and Fred Pugh's book on brakes eons ago so you're more familiar than me right now.
Overall, I'd guess your plan is sound. Here's what concerns me; drag and weight.
Downforce is only effective when air feeding the downforce devices is controlled and 'aimed' at them. Not sure that will happen here as you're trying to evacuate and channel air for cooling improvements. Adding a chin might compound the problem. I just feel that all the blocking panels might cause higher drag. No empirical experience to back my guess.
After you solve all this nose stuff you got the huge drag-maker, the cockpit. Think maybe a hard tonneau.
Which leads to my other concern; weight. Sure, the tin you add in the nose may only be 10 pounds-worth but you'll have substantial roll protection weight when done too. You were super weight conscious with block, trans and all bits. Maybe carbonfiber for all your ducting / fairing and tonneau??
OK how about a crew hat instead of shirt??
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  #92 (permalink)  
Old 01-24-2014, 09:13 AM
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I've wondered if aerodynamically the oil cooler wouldn't have been better mounted in front of the radiator on race cars with the lower duct opening left open or ducted to brakes, etc. I wouldn't think on a track car that didn't spend any appreciable time lugging around at low speeds, that it would cause any cooling problems. I could be wrong.
Actually Smith cannot stand stacking heat exchangers. That said, if a car has fenders he does not consider it a real race car. It may actually be better to move an oil cooler to the front fender well and use a fan. Your idea of using the lower intake for the brakes is a good one. I still am a bit of a traditionalist.

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This is an interesting project. Very entertaining to follow.
Glad you are enjoying yourself
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  #93 (permalink)  
Old 01-24-2014, 10:10 AM
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Quote:
Originally Posted by ERA Chas View Post
I read Smith and Fred Pugh's book on brakes eons ago so you're more familiar than me right now.
Overall, I'd guess your plan is sound. Here's what concerns me; drag and weight.
Downforce is only effective when air feeding the downforce devices is controlled and 'aimed' at them. Not sure that will happen here as you're trying to evacuate and channel air for cooling improvements. Adding a chin might compound the problem. I just feel that all the blocking panels might cause higher drag. No empirical experience to back my guess.
After you solve all this nose stuff you got the huge drag-maker, the cockpit. Think maybe a hard tonneau.
Which leads to my other concern; weight. Sure, the tin you add in the nose may only be 10 pounds-worth but you'll have substantial roll protection weight when done too. You were super weight conscious with block, trans and all bits. Maybe carbonfiber for all your ducting / fairing and tonneau??
OK how about a crew hat instead of shirt??
The weight is really insignificant - I am using .050 sheet. I am trying to accomplish several things

1) Air entering the nose of the car to be used for cooling and nothing else. Any air that is not needed to cool - do not run thru the car move preferably around.

2) Create a low pressure area under the car

Ducting - It's been a bit of a chore to this point. I am starting my 4th gen wall panels today. The aluminum makes it much easier to shape. I suppose I could copy in CF. I will weigh the ducting.

Roll over protection - What on earth do you have in mind? What is wrong with what I have. Somehow we got here. They turned the one into a puddle jumping the Alpha and walked. They still run bikes at 180 on a regular basis.
Unless they won't let me run it I plan to run what I have, but I am interested in what you think I will need.

Tonneau - exactly right - quite aways away, but we will have to do something.

While we are here - can I get the Webers under the hood with no scoop?

I plan to use aluminum sheet for all cold air ducting and the first belly pan back to the front wheels. My thinking here is if it gets damaged we can beat it back to shape with a hammer. I plan to use CF from the firewall back. I love your CF tonneau, but I don't know how to get there. It will take some study. I am also seriously considering a fairing behind the roll bar.

Drag is a concern but there has been quite a bit published on the use of spoilers and it is surprising that adding spoilers can help with drag by getting the air away from the car. There is less drag pushing air around the car than letting it go under. Also, the beautiful chassis is both extremely dirty and extremely voluminous which adds to the static pressure under the car.

At this level it's a lot of voodoo. All we we can do is fab and test, but there is published data to at least give a path. I expect the car to be very fast. If it is not, it will be a complete failure. Throwing hp at it would not come unless we have a stable, high speed car. What would be better, is to have a very fast car with Brent's disappointing mouse motor.



Roll protection?
Hood Scoop?

Could really help with the hat -

Shirt went with the paint

x-chr

Last edited by ERA2076; 01-24-2014 at 10:15 AM.. Reason: Add Graph
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  #94 (permalink)  
Old 01-24-2014, 10:17 AM
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One other thing - we are not trying to run 200 - we need to run 155 - that is all.
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Old 01-24-2014, 11:35 AM
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We are looking at he top of the cooler and it's shroud. Notice where the fins start on the radiator.



There is nothing to be gained by trying to cool the radiator support and it only increases the angle which is not what we want. The lower chamber cannot be clean. All we can do is try to minimize the angles as much as possible as well as minimize the volume.

Here is the floor for the lower chamber. It mounts above the rad support closing that region as a dead air space. The angle is to steep for the air to stay attached.



This is a riser which we do not plan to use, but I hope you can see where we are headed. A roof goes on top of the riser angled down at 8 degrees towards the radiator. I want to use the 8 degrees to reduce the volume of the lower tract trusting the air will stay attached in the larger tract. The lower tract feeds seven rows of rad tubes.



Feed clean straight air thru the rad and not have high pressure turbulent air packing and trying to lift the front of the car.

The additional duct panels weigh .9 lb.
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  #96 (permalink)  
Old 01-24-2014, 12:30 PM
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Exactly what I am talking about

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Old 01-24-2014, 01:08 PM
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Quote:
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One other thing - we are not trying to run 200 - we need to run 155 - that is all.
I ran 155 with zero aero and wide open cockpit but with 550HP. You can easily do it near 500 I'm sure. But it was on glare ice up there and my six-hole was clamped shut.
Couple of things:
I think Webers on your 8.2 deck is good with no scoop. O'course, you wanna think about getting cold air to them...
Couple guys on here with FIA's run Webs and I think Allen's beautiful green car with LeMans roof has no scoop. Try a search.
I really think at this stage, you have to get with Morris Clement on here about aero and downforce. With an Indycar background, Morris built what I consider the ultimate Kirkham track car. Very big speed at very big tracks. His highly detailed build was posted years back on Gasholes (dunno about here) but I forget his chassis number. Maybe start a 'Hey Morris!' thread to get his attention.
He has the experience to confirm or bust your theories and prolly save you a lot of blind-alley work. His path went to 18" wheels, serious but-not-ugly roll protection, gargantuan brakes, 700 or so HP, diff cooler, belly pans and ultra-trick everything.
You can benefit if he has the time to cooperate. I'm just a crazed street rat that managed to not kill myself on street or track. (Bless you Skip Barber).
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  #98 (permalink)  
Old 01-24-2014, 02:36 PM
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1) I am an amateur

2) Since I don't purchase from them, I am not comfortable asking builders outside of Bob and ERA.

I have read a lot of Morris work on CC. A great contributor.

Sure would be interesting to see what Bob would build, if he did not have to make money.
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Old 01-24-2014, 02:39 PM
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Old 01-24-2014, 03:14 PM
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Quote:
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1) I am an amateur

2) Since I don't purchase from them, I am not comfortable asking builders outside of Bob and ERA.
Allen is not a 'builder' or constructor if that's what you mean. Amateur just like you and me. So is Morris. They happily share info with their contributions.
You're getting into Morris' league which is why I suggested he'd be more helpful than I am.
Bob just loves kayaks...
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