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DanEC 02-22-2014 03:52 AM

Even with all you have done I'm surprised by how much weigth you managed to get off the car. Your down in FFR and all billet aluminum Kirkham territory now. Very surprising considering how robust the frame and body are on the ERA. Sorry, I'm abosolutely of no help on your questions.

On your transmision height I think I would measure your U-joint angles before getting too concerned. I had my tailshaft sitting at 3-3/4 inches per Bob/Doug and due to some interference betwwen the shift boot/transmission lever/tunnel they recommended I raise it some more to resolve the issue. They sent a 5/8 inch spacer for the mount but I only used about another 1/4 to 3/8 inch movement to clear things up. With my tunnel in place I can't check my angles right now but ERA didn't seem to believe it would cause any problem.

ERA Chas 02-22-2014 07:36 AM

Quote:

Originally Posted by ERA2076 (Post 1287359)
What about the body roll? Does the pic seem typical? I ask because I may need to stiffen the bars some.

x-chr

For an ERA I think so. Bruce's #3170 is tighter but as radical as yours.
Dan, I think Cliff wants the weight as low as possible for Cg.

ERA2076 02-22-2014 02:37 PM

Weight and placement are at the front of the agenda, but like the suspension geometry, I am limited by commitment (t & $)

I remember now how we got to 3 points. We had the car on 4 points, were checking engine level, and noticed one of the points was not touching. We tried to ratchet and it moved the force to the other three but we could not close the gap. I don't know why I was surprised, it is exactly what should have happened. Once demonstrated we set the steering as the primary critical feature and went to 3 points.

Dan - great point on the joints.

Chas - w/ respect to the joints - shim the pumpkin down - LOL

Dan - an ERA chassis with this weight does make me smile. We are in Shelby territory with a real suspension and another 100 hp.

Not sure we have enough trans, but for now :cool:

We still need some water and some more oil for the accusump, but there is some give back in the wheels, drive shaft, & front calipers.

a427sc 02-22-2014 05:07 PM

checkout Hoosier Street TD Hoosier Racing Tire - Tires Designed For Champions

45160 P225/45D-15 H 7.6" 23.0" 72.5" 6.5-8.5" 7.5" 8.5"

26.6 vs 23" bias ply, treaded, a little harder compound. there's 1.8" for ya.

ERA2076 02-22-2014 07:41 PM

That is some serious gain. I'll have to take a look at that.

x-chr

ERA2076 03-05-2014 11:56 AM

Quote:

Originally Posted by ERA2076 (Post 1287485)
That is some serious gain. I'll have to take a look at that.

x-chr

I have the car on the floor and have spent several hours working on ride height. All of my front suspension is built around the 26.5 tire. The shorter tire could require some rework (shock length is a concern). I do not like the look of short tires under a Cobra.

Still end up 4 7/8 to the floor in the front with the the front suspension square and 26.50 tire. I have not modeled the rear suspension yet with respect to roll center movement so I am hoping that all works out well i.e. front and rear RC can be made to move together fairly close at a decent ride height in the rear. For now I have the rear set at 5 1/4.

https://imagizer.imageshack.us/v2/55...90/32/x2sw.jpg

Here is an advantage to being short - the steering wheel is in the same plane as the shifter.

https://imagizer.imageshack.us/v2/55...0/841/jt4n.jpg

ERA2076 03-06-2014 10:53 AM

Quote:

I have the car on the floor and have spent several hours working on ride height.
This is mis-leading. I actually worked on getting the lower control arms level to the ground using a digital angle finder. The lower control arm parallel to the ground determined the ride height which came in at 4.875 with a 26.5 tire.

A problem with shorter tires is getting the wheel gaps aesthetically pleasing while maintaining good suspension geometry. If you run short tires and try to lower to make the wheel gaps look correct, the front cross member drops thru the lower control arms and you lose control of the front roll center in the transverse plane when the car rolls (according to my software). A good way to solve this would be to move the pivot points - that is above my pay grade. I am using extended lower ball joints to move the spindles up with a down side being increased steering effort and it sits where it sits.

Colin Chapman said something to the affect -

"Any suspension will work, if you don't let it"

My goal staring out is to limit front and rear, outboard roll center movement as much as possible and to try to get them to move together in as small a window as possible and then test.

chr

ERA2076 03-06-2014 06:06 PM

https://imagizer.imageshack.us/v2/64...0/138/we00.jpg

ERA Chas 03-06-2014 07:45 PM

You may get a lot of glare unless you black this side of dash...
Maybe tach and oil press too small??

ERA2076 03-06-2014 08:50 PM

I have not installed the tach. I boned the steering column slot and need a small repair. Still have to cut the access panel for the electrical. There is room for brake bias adjuster and fire suppression actuator next to the bat disconnect.

Will paint it satin black and possibly texture if we can come up with something suitable. I kept my street dash complete with gages and wiring. It occurred to me there is no reason to cover this one since I still have a beautiful street dash that can easily be re-installed. This one is for the track. I did paint the back white - what a great idea - it is amazing how well that works.

The 2 gages installed are water temp and oil pressure - they are very easily viewable thru a 13' Momo.

ERA2076 03-27-2014 01:16 PM

We pulled the FIA off the rack so we could bolt some aero on the trainer. It worked very well. I was able to hold my foot to the floor thru turn 9 at PIR. This is an off camber corner and the thing wants to drive right off the road. The splitter seems to have been enough to get me thru though it is now apparent the shocks are under damped for that kind of speed.

https://imagizer.imageshack.us/v2/64...90/46/msog.jpg

Oh come on - it says COBRA right on the rear bumper. :cool:

https://imagizer.imageshack.us/v2/64...0/163/qzza.jpg



I was still able to move ahead on the FIA. We got the steering welded up so it is much easier to move around.

I got the dash back this morning. The shop that painted it was amused by the white paint. They just finished a Tiger and the the techs comment was " I wish I would have known about that, we would have finished the Tiger that way".

https://imagizer.imageshack.us/v2/64...0/716/qnky.jpg

https://imagizer.imageshack.us/v2/64...0/822/przj.jpg

ERA2076 03-27-2014 04:46 PM

https://imagizer.imageshack.us/v2/64...90/89/mpvm.jpg

blykins 03-27-2014 05:56 PM

Please light that motor off soon....not good for them to sit for months and months.

Car looks really good cliff.

ERA2076 03-27-2014 06:44 PM

Thanks Brent -

I'm working on it - I have a ways to go. I poured oil in it and we spin it with a wrench periodically.

While you are here, what do you want me to do with the lash?

x -chr

blykins 03-28-2014 04:58 AM

Whatcha mean cliff?

ERA2076 03-28-2014 08:10 AM

valve adjustment - spec and frequency.

You never should have left in a position to tear the car apart, :LOL:

chr

ERA2076 04-03-2014 06:26 PM

https://imagizer.imageshack.us/v2/64...90/69/7b2v.jpg

ERA Chas 04-04-2014 04:50 AM

Turn the lights off-too bright under there!!

DanEC 04-04-2014 09:17 AM

Have you added the additional tube brace across the dash opening and fabricated the steering column mount? In looking back at the early pictures in this thread I don't think I see it.

ERA2076 04-04-2014 03:26 PM

No - we added only the cross brace you see in the picture and the 1 spherical bearing. We have tightened it all down and it feels rigid. I was concerned about the moment from the bearing out to the end of the wheel, but I spoke to Woodward about it and the tech thought I was crazy. They run this steering in Sprint Cup cars and you see some long arms when you see them on T.V. I was the only one in the shop that wanted to run extra support. The guy at Woodward told me you cannot run 3 spherical bearings in sequence as it will cause binding.

The cross tube we added is welded back to the fire wall cross brace with plate (3 places) and small angle to stiffen the plate. If I were to do it again I would use round tubing for the brace and move the bearing closer to the dash. We have some time into this and I did not want to reconfigure it to move the column bearing out. The present location of the column bearing does add some integrity down to the foot box bearing because of the shorter beam.

Things I like - it is very positively located, positively attached (the nut is 1 1/8), and it is lighter.

Concern (unfounded ?) - bending moment from column bearing to wheel (tubing is quite robust).

I am going to run it - if it is not adequate we will rebuild it.

Side note => With the 225 tires and 175lb off of the front, the steering is quite easy. :)

chr


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