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My messy new shop
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Author:  GonzoRacer [ February 16, 2012, 9:52 am ]
Post subject:  Re: My messy new shop

Yo Marcus-
Man, you are really doing some cool stuff in here! Pretty amazing data base and "set of drawings" you've gotten together... Good on ya, as Kiwi Dave might say!

On those header dimensions, check out Speedway's website, they have info on dimensions of headers they sell. Same drawing on all of 'em, which shows a small-block Chebby, but the numbers are right. This is the block hugger Ford header: http://static.speedwaymotors.com/images/charts/9300201.gif with that last bit, the 9300201 being part number. The Mustang shorty is a Summit part... I'm still lookin' for diagrams...
:cheers:
JDK

Author:  GonzoRacer [ February 16, 2012, 3:28 pm ]
Post subject:  Re: My messy new shop

These are not the ones we were talking about, but wouldn't they look sweeeeetttt stickin' out of the side of the bonnet???

http://static.speedwaymotors.com/images/charts/930FR100.gif
Attachment:
Headers.jpg
:twisted: :mrgreen:

:cheers:
JDK

Author:  cheapracer [ February 17, 2012, 2:20 pm ]
Post subject:  Re: My messy new shop

...and somewhere to drive it when it's up and running ..

http://www.youtube.com/watch?v=VThQM_XfkOY

Author:  horizenjob [ February 18, 2012, 2:59 pm ]
Post subject:  Re: My messy new shop

The Wilwood spindles weight the same as the stock Miata ones. I'm not too worried about their weight and the strength is appropriate for a V8 roadster that will see track time. I do care about being able to run proper slicks on 13" rims though. The weight savings there is really large. More then 50 lbs. of rotating mass pretty easily, just in tires not counting the rims.

In the picture of the Chevy crate engine it looks like it has a very compact set of "block hugging" style headers. I think that's the best choice. I'd like to put the top rail where is makes most sense and route exhaust around it. People always put curves in headers, but not chassis rails. We'll see. Every day I get up and plan world domination.

The mid plate is not something I have ruled out, but I am avoiding it while I can. Once you do that you pretty much tie down where the motor and the front bulkhead go. This early in the game being able to move things even a couple of inches might make a difference. If I had a junk V8 handy and some real life chassis mockup going on I would be more comfortable. I think I need to mock up the pedal assembly and see how small the foot well is when moving the engine back.

The mid plate mounting and the rear transaxle go well together. Lot's of foot room and simple strong framing. Just not knowledgable enough yet to carry that off confidently yet.

Maybe I need to go borrow JD's junk V8 when he's done with it.

I should go read Kippermans blog or web page and look for more photos...

Author:  horizenjob [ February 18, 2012, 3:27 pm ]
Post subject:  Re: My messy new shop

Thanks CR, I'll try looking at some of that stuff. I was wondering if the SketchUp physics stuff would be nice to animate the suspension. If I could do something like make joints with bearings that would be cool. It seems from some things I've seen that you can do calculations etc. and then maybe actually show roll centers or the frame rolling etc. That would be the cat's pajamas....

We're getting to where we need full size mockup work with scrap wood, I think. It just seems hard to visualize some things on a computer model.

Author:  horizenjob [ February 18, 2012, 5:14 pm ]
Post subject:  Re: My messy new shop

Here's an interesting Sketchup of a Jeep actually crossing terrain with moving suspension.

http://www.youtube.com/watch?v=89OT86TZFGQ&feature=related

Maybe a Sketchup string computer for suspension wouldn't be so hard....

Author:  seattletom [ February 18, 2012, 8:47 pm ]
Post subject:  Re: My messy new shop

horizenjob wrote:
...In the picture of the Chevy crate engine it looks like it has a very compact set of "block hugging" style headers. I think that's the best choice. I'd like to put the top rail where is makes most sense and route exhaust around it. People always put curves in headers, but not chassis rails. We'll see. Every day I get up and plan world domination.
...If I had a junk V8 handy and some real life chassis mockup going on I would be more comfortable. I think I need to mock up the pedal assembly and see how small the foot well is when moving the engine back....
Agreed that its better to design the headers to fit the chassis rather than the other way around. The stock LS exhaust manifolds are good starting point and headers take a while to build and can always be added latter.

I was planning to use a "plastic" long block from these folks http://www.payr.com/engines-chevy-smblock.htm and bolt up a bellhousing and (empty) tranny case to do the final fitting and mount locating. A number of reasons: The blocks are very light (you can man-handle them at table height even if you have a ceiling too low for a cherry picker), have all the external bolt holes accurately placed, are reasonably priced ($375) with an excellant resale, and allow deferal of the big $$ for the real motor until install time. Should net out way ahead when you figure the cost of back surgery... Anyway, if enough space is reserved for things like feet, bellhousing, motor, tranny, etc. the final fitting can be done in the metal.

That said, a wood mock-up with a plastic motor would be cool, plus it would allow creation of some good vroom-vroom sounds. A lot more fun than making race car noises while sitting on a laptop :D

Author:  GonzoRacer [ February 19, 2012, 9:10 am ]
Post subject:  Re: My messy new shop

Yo Marcus-
I finally got to the shop in daylight and remembered to take pictures of that Ford 8.8 IRS differential. That's the good news... Several of them came out so bad as to be useless. I'm gonna blame the computer here at the house for buggaring them up, but it might be my lousy photography skills. I'll take some more soon, maybe today if the rain lets up and we go work on it...

Across the front and center-to-center on the mounting points--
Attachment:
2 18 12 Diff Front.jpg


The attachment points at the rear--
Attachment:
Diff Rear Mount.jpg


The overall length--
Attachment:
2 19 12 Diff Length.jpg


Width across the "punkin"--
Attachment:
2 19 12 Diff Width.jpg

I kinda got the tape offset, note the 3/4 inch stickin' out beyond the measuring stick... :oops:

Height of the "punkin"--
Attachment:
2 19 12 Diff Height.jpg


And, just for giggles, one of the "not too good" examples-
Attachment:
2 18 12 Diff Height.jpg


So, a small contribution to the body of work you've accomplished here. I'll try to do better next time...
:cheers:

Author:  waltj [ February 20, 2012, 12:55 am ]
Post subject:  Re: My messy new shop

Gonzo,
Picture is clear, you just ran out of film for that shot :twisted:

Author:  horizenjob [ February 23, 2012, 2:47 am ]
Post subject:  Re: My messy new shop

Thanks for the pictures JD, sorry I forgot to mention that earlier....

Author:  GonzoRacer [ February 23, 2012, 11:26 am ]
Post subject:  Re: My messy new shop

horizenjob wrote:
Thanks for the pictures JD, sorry I forgot to mention that earlier....


You're kiddin??? It took me a month or more to remember to do 'em at all :oops: and then I had to do some of them over because the first ones weren't usable :oops: ... And you're apologizing to me??? That's gotta win the LocostUSA "Graciousness" award. :roll:

I hope they're helpful. Now I need to get that diff to mounting plane measurement... Will try to remember that this weekend...

:cheers:
JD "No Short-Term Memory" Kemp

Author:  horizenjob [ March 5, 2012, 3:24 am ]
Post subject:  Re: My messy new shop

I had a friend who used to wrench on Formula Atlantics review some of my stuff the other day. I wasn't able to bring a laptop so just grabbed some of the pictures that have been posted here including one of the pictures from the Grape FEA runs.

He liked the shear tabs in the front suspension. Enough that I think I will redraw the back suspension to include them too. Did not like the front bulkhead tubes with their compound angles. Hard to get right and even harder to repair I think we his issues. So those tubes may become the same as the tubes that mount the aft end of the wishbones and then the front heim joints become perpindicular to the chassis. I think that's what he wanted, may have to clarify. That makes it easier to adjust them without causing bending loads on the arms.

The front coilovers shouldn't go the the wishbones mounts. So I think I will try to move the top cross piece of that bulkhead forward a little and extend it outwards to take the coilovers.

He thought it was worthwhile to try and work out the rear suspension with out the more normal box welded to the bulkhead behind the driver. Don't think he was convinced I'm there yet though. He suggested protection for the gas tank from broken half shafts.

There were some other comments too. I'm part way thru some of these changes along with other cleanups and will try to get some pictures up in the next day or two.

We are getting closer and are well into the stage were it is largely done with most of the work still in front of us! It never seems to end.

Someone has offered a hand with running numbers on the suspension and the initial results are looking good. There is no reason for surprise here, we are trying for a straight forward and conservative design. I hope we can start showing those results one of these days soon, it's just taking time to get real measurements of the parts and learn wishbone etc.

Author:  a.moore [ March 6, 2012, 11:26 pm ]
Post subject:  Re: My messy new shop

horizenjob wrote:
Did not like the front bulkhead tubes with their compound angles. Hard to get right and even harder to repair I think we his issues.


You might want to look into making them from round tubing to eliminate the compound angles. Round tube doesn't know which side is the front or the outside - its all the same and it makes fabricating the bulkhead much easier.

Author:  horizenjob [ March 7, 2012, 1:54 am ]
Post subject:  Re: My messy new shop

Thanks Andrew, that's a good idea. I have had a little more discussion with my friend and I think I somewhat misunderstood his comments.

The vertical tube in the front of the frame is not cut on a compound angle. I fixed that quite some time ago, but it looks that way from some angles. I'd forgotten that until I started to move the tubes and look more closely.

The vertical to support the rear legs of the front wishbones would like to tilt back a bit to provide castor, which wold be a compound angle, but at least symmetrical. I am going to try and avoid that though. So I am thinking the mounting plates for the wishbones will be spaced out 1/4". That would make for a 1.5" space between the shear plates and allow for shimming the wishbones to adjust some castor and adjust for build tolerances etc. Then the heim joints can also be adjusted to move the outboard end front and back.

It will not be the easiest setup to adjust, but should not require it often. In the years I drove my FF seriously, I almost never adjusted anything, except for ride height at hillclimbs. I guess I sometimes did the anti-roll bars. The driver was what seemed to need the most "adjusting"...

Author:  horizenjob [ March 21, 2012, 1:18 am ]
Post subject:  Re: My messy new shop

I keep trying to clean up the frame in the back of the car for the diff mount and the lower parallel links. I kept going around and finally realized there was always going to be something I didn't like about it and I should just pick what seemed to be working best. This is looking simple and fairly clean. I put it into the FEA model and it is very nearly as stiff as where I started. This solution loses perhaps %2 of the stiffness but it mounts the diff and the lower suspension and I don't get a headache looking at it. I think the car now flexes .005" more under load. I also checked it for cornering loads from the suspension and that seemed strong too.

The new tubes are in red.

Before then after:

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