Sport's race car build

[sport.]

Hey Bob I made some progress ,Well I guess my leg didnt make any progress but the chassis has ,It is now all jigged up all the seams are welded 100% the X is in the chassis the front lower control arms are tied.Now to my leg progress.My leg is still a mess I need to have more sugury.I am still in a brace from the hip down still. and I cant walk without crutches.My buddy Bruce has done all the work for me I cant thank him enough.I get to sit in the lawn chair and supervise for once (LOL)We are getting there.

[parklane]

Chad  Glad to see you back on the chat line. Just don't over do it with that leg, because your're in a panic to get going on that roundy round. It takes a lot longer to heal the second time around!
later
John

[SKR8PN]

Hey Sport.............how about an update on your progress..........
Both physically AND on the race car

[unklian]

How does the height and angle of the Chevy II windshield compare to some of the more common body styles?

Different is good,but aerodynamics is also worth something.

[sport.]

Hey Sport.............how about an update on your progress..........
Both physically AND on the race car

SKR8PN Thanks for askin',The jig table is done, The race car chassis is all prepped fully welded the X is in the lower front control arms are tied,We are gettin' ready to start fabbing the cage.....As for the Leg it's not very well,I have to go in for more surgury after X-mas,I have been gettin' around on crutches.I am still in a brace from the hip down tho...I took Bob's advice and got a leather welding apron so I could do some work myself.But My buddy Bruce has come threw in a big way of help.

Hey Bob are ya still out there?I havent heard from ya in a while?

[sport.]

How does the height and angle of the Chevy II windshield compare to some of the more common body styles?

Different is good,but aerodynamics is also worth something.

Unklian The Chevy II roof line is 3 inches lower than a stock Monte Carlo.The angle on the winshield is not that much different.Plus I am gonna channel the body just a little, so it will be even lower yet

[Bob Paulin]

Hi Bob,I hope you and your family had a good Christmas! I was wondering we havent started bending up the cage for my project yet.But I remeber you said something about building a bridge well inside the cage to tie the RF spring pocket and the RR.

Would you mind explaining the best way to go about this?

Bend your front stretch bar to reach the chassis just above the idler arm mount. I like the looks of about 45° on that bend. I don't like 90°, and NASCAR frowns on 90° or straight down bars for crushability purposes.

Run it straight back - just inside where the right jacking bolt will be - to the dash cross bar, then back to the center main hoop cross bar, then back to the frame next to the right rear spring pocket.

Now, run a bar underneath and parallel with the first bar from about halfway up the front frame kickup to the rear frame kickup. Eyeball it and make it look good.

Triangulate from the lower bar front mount straight back to where the upper bar meets the dash bar. Run a bar from the center of the dash bar down to where the lower bar meets the frame kickup.

Drop bars straight down from the upper to the lower bar at the dash bar and the middle main hoop bar. Run an "X" between these bars.

Also run short bars from the lower frame-length bar to the cage uprights.

Finally, run a bar from the intersection of the upper bar and the center main hoop bar back to the spring pocket area.

Short bars from the door "X" to the frame and to the chassis "X" will strengthen things up, as will a vertical bar up through the middle of the door "X" from the lower to upper bars.

The left side front stretch bar should mount to clear the jacking bolt on the outside. Run similar stretch bars from the dash bar to the frame, and, given the offset of the left door bars, do what you can to create a space frame - although the left side isn't as critical as the right side.

If you have done the right side correctly, the right side perimeter frame rail should look like a nerf bar only.

No stressed bar should be unsupported for more than ten-times-its-diameter - or, with 1.75" tubing - 17.5 inches....and no bar should be tied into another bar without a bar being within 17.5 inches to support it.

Personally, I like to see a bar exactly on the opposite side of the tubing where any bar ties in.

Also, you might want to drop smaller diameter, bolt-in tubes from the front stretch bars straight down to a point next to the jacking bolt mount. You'll have to notch the left a-frame a bit more for his, but that's okay. Inside the jacking bolt on the right side, outside on the left side.

They MUST be bolt-in so you can remove the upper control arms.

The front control arms are in getting new
ureathane bushings put in the uppers, and the lowers are getting steel like
you suggested.I have all new tie rods.The spindles are all sandbated and I  had them magna-fluxed by a buddy of mine.

I'm just finishing up my first reading (believe me, there will be several more!) of Allen Staniforth's "Competition Car Suspension" ($40 at Barnes & Noble), and he's got me excited about playing with roll centers - or as you and he call them, "centres".

He describes a "string computer" one can build with poster board, sticks and string which will help you locate your own roll center and watch it migrate during bump and/or chassis roll.

It got me thinking about moving the static roll centers around in Dan's car in order to come up with the sort of migration we want, and I think we can do it by reaming out ball joint holes in the spindles.

I fired up my chassis setup software, and discovered that moving the upper and lower ball joints deeper into the spindle by as little as one-eighth inch (0.125") can change the static and dynamic roll centers quite a bit. Static ride height also changes things in motion.

I was talking with Dan Sunday night, and I told him what I want to do.

He's so happy with the way the car works right now, that he said he was reluctant to change things so permanently and drastically - but, since nearly every change I have suggested has worked pretty well,  he would if I really, really wanted to.

I told him we could experiment with spare spindles - which he has good access to - and his mood picked up - as long as he can go back to his current setup if it doesn't work....LOL!!!!

I have a dummy block set in the  chassis, the crank centre line is 12'' from the ground at a 6'' ride height  the number #1 sparkplug is lined up with the centre of the ball joint. The solid motor mounts are in.I mounted the tranny off the X in chassis.Do you  ever do this?If you think it is wrong I will change it,It's only tacked in
right now.

Done correctly, I like solid mounts....BUT THEY MUST BE *SOLID* MOUNTS!

If you are using the Moroso-style bent plates, you'll start to have trouble with cracking rear mounts, tailshaft housings, even bellhousings.

You can install a Moroso-style mount and bolt it solidly to the chassis. Stick a crowbar between the chassis and dummy block and you can create visible movement.

A well-designed mount that bolts the block solidly will help the engine to serve as an engine bay crossmember between the left and right upper frame rails and suspension mounts.

That's why some people use front and rear engine plates....

Once you have it all fabricated, put a dial indicator on the block and put the crowbar to it. a few thou isn't bad, but any movement you can see with the naked eye needs to be refined.

The rear-end housing is sandblasted.I am waiting for all the new
axle seals.I have a spool for the rear and a new set of gears.I only do a
little at a time beacause compensatio doesnt pay very well.The progress is slow but my leg progress seems to be even slower.I hope your still
interested in my project? How Dans new car comming along?

Actually, we haven't found a clean-enough chassis yet. I'm also thinking that Dan is afraid that I won't be able to improve on what I've given him already, but I KNOW that isn't the case.

In the meantime, I'm chasing down some snowmobile shock work from local shops to stave off the wolves.

Wish me luck!!!!

I'm going through an entire educational process about the benefits of dyno-testing shocks with most of these people.

B.P.

[sport.]

Thats basically how they do the IMCA modifieds right? I am just tying to invision it without being allowed to run an off set cage.I just come in from the garage I have the rear hoop pretty much figured out.It's all marked and set up to be bent.I will give this new bender a go maybe tomorrow,If the leg feels better.I am pretty sore right now.

[PeterR]

I'm just finishing up my first reading (believe me, there will be several more!) of Allen Staniforth's "Competition Car Suspension" ($40 at Barnes & Noble), and he's got me excited about playing with roll centers - or as you and he call them, "centres".

Bob,
You certainly will read that book many times.      It is particularly well written and a great mix of the history, the machines, the people, and the technology.    

I think one of the reasons it is so appealing is that any chapter can be read in isolation as a half-hour diversion.  Also, unlike so many books of its type, it is not riddled with technical mistakes.    I can only remember two errors and one was probably a typo.    The author even manages to avoid referring to the non-existent "centrifugal force".  

The section on amateurs and the string computer illustrates there is an opportunity for the low budget enthusiasts who do not have the bankroll for rows of computers and Snap On roller chests.

Perhaps the only sign of its age is that since it was written the almost universal ownership of personal computers means it is ready for an update with a chapter on using standard software to perform some of the tedious calculations.    In about an hour, a person with basic skills in Excel can set up a spread sheet to calculate weight transfer effects of g forces and suspension parameters, and in about two hours a spreadsheet which determines the position of instant centres under roll and bump, then presents it in both tabular form and a scale line drawing.  If the book included these on a CD so the couple of hours could be reduced to a couple of minutes then that would truly be icing on the cake.

[Bob Paulin]

Thats basically how they do the IMCA modifieds right? I am just tying to invision it without being allowed to run an off set cage.I just come in from the garage I have the rear hoop pretty much figured out.It's all marked and set up to be bent.I will give this new bender a go maybe tomorrow,If the leg feels better.I am pretty sore right now.

I believe the IMCA Mod is a good example.....

In your case, I would bend up two symmetrical hoops to comply with the non-offset cage rule - maybe slide them both to the port edge of the chassis rails - then run the bridgework as I described.

B.P.

[Bob Paulin]

Bob,
You certainly will read that book many times.      It is particularly well written and a great mix of the history, the machines, the people, and the technology.

And, when it is read in the correct frame of mind, the principles can be applied to most forms of racing that require the car to turn - not just single-seat, Formula cars.

I think one of the reasons it is so appealing is that any chapter can be read in isolation as a half-hour diversion.  Also, unlike so many books of its type, it is not riddled with technical mistakes.    I can only remember two errors and one was probably a typo.    The author even manages to avoid referring to the non-existent "centrifugal force".

Since the book was written in "English", and I read, write, and  speak "American" - colour versus color, you know - I probably would skip right over any typos.

Besides, this is the third edition...revised in 1999. Maybe the typos have been fixed???

I started out jumping around - especially to see what he had to say about shocks, but I then steeled myself to read it - at least once - from cover to cover. (I'm currently giving the string computer chapter a second read just to make sure I understand everything I believe I know about it....LOL!!!!!!)

I can, however, see its usefulness as a quick, half-hour chapter read to refresh the memory, and to pick up a little detail here or there that might have been missed in past readings.

I can also see areas pertaining to design and fabrication taking precedent at this time of the year when machinery, tools and cars are being built and/or refreshed, while areas pertaining to troubleshooting and adjustment would have more importance once the car hits the race track.......

.....at least that's the way I have used my other technical reference materials over the years....some of which are now quite dog-eared.

The section on amateurs and the string computer illustrates there is an opportunity for the low budget enthusiasts who do not have the bankroll for rows of computers and Snap On roller chests.

That's right up the alley of most of the people with whom I work - working class people who spend  their disposable income (sometimes a little more)  on race cars.

An extra hundred dollars is used to buy a new tire - not computerized chassis analysis and setup software.

As a "chassis guru", it is I who is expected to make that investment....LOL!!!!

Perhaps the only sign of its age is that since it was written the almost universal ownership of personal computers means it is ready for an update with a chapter on using standard software to perform some of the tedious calculations.    In about an hour, a person with basic skills in Excel can set up a spread sheet to calculate weight transfer effects of g forces and suspension parameters, and in about two hours a spreadsheet which determines the position of instant centres under roll and bump, then presents it in both tabular form and a scale line drawing.  If the book included these on a CD so the couple of hours could be reduced to a couple of minutes then that would truly be icing on the cake.

While that is certainly true, a lot of people with whom I deal would rather have that hands-on feeling of a mock-up such as the string computer.....

.....and, as a former teacher, I also understand that different people process information differently, and learn from different presentations - sometimes needing the information to be presented in differing forms ranging from printed to hands-on.

The mock-up is also an easy-to-demonstrate unit that helps people to visualize and understand what you are telling them needs to be done.

I have a set of programs from Stock Car Products that help to determine roll centers, weight transfer, etc. that I use on a car in the shop, but they feel awfully clunky to use at the race track.

While I haven't really gotten into the appendices yet, I'm hoping to plug some of the "supporting math" formulae into an Excel spreadsheet to quicken some of the calculations over opencil, paper and a hand-held calculator.

B.P.

[sport.]

I think I am gonna have to check that book out.,Is there any other good books that may help me down the trail?


Bob, I bent and mounted(tacked) the main roll bar,I shoved it back over the trailing arms .I mounted it off square tubing off the side of the chassis and I gusseted the tubing and capped the ends,It was a major mile stone.......for me anyways....Mr.Hop-a-long...Maybe some more progress reports today....I'll let ya know....

[Bob Paulin]

Hey Bob, Is there any good chassis/supension books ,you think I should be taking a look at.To help me gain more knowledge??

There are really quite a few different publications out there.

What would work best for you would depend on your current level of knowledge, and where you want to go.

For example:

Steve Smith Autosports publishes a number of very basic books such as "Building a Pro-Stock", Building a Street Stock", "Race Car Fabrication and Preparation", "Street Stock Racing Technology", etc.

They are very basic in nature, and to be completely honest, a lot of the technology is outdated....but much of it is still valid.  

For someone starting out at point zero, they could be a rapid course to better understanding of the race car.

He recently developed an oval-track "Pocket Reference" book that will tell you, "... if the car is doing this, change that"....again, very basic, but it should help most people to get their cars pointing in the right direction.

He advertises in most oval-track publications such as Speedway Illustrated, Circle Track and Stock Car Racing. He also has a website.

Next, in my opinion, would be the Carrol Smith series of books "Engineer To Win", "Prepare To Win", "Tune To Win", "Drive To Win" and "Nuts, Bolts, Fasteners & Plumbing" aka "Screw To Win."

Smith was the engineer on the Ford GT-40 program that won at LeMans,. and has worked closely with another Carroll - "Shelby" - on many Ford and Shelby projects.

Smith also developed a pocket reference book just before he passed away a year or so ago, but I believe his son is maintaining the publication business - also with a website.

Paul van Valkenburgh's "Race Car Engineering & Mechanics" was a great textbook-style publication in its initial production.

The update, however,  has been converted to the HP Books format with tons of pictures, and - in my estimation - a "dumbing down" of the technical content and the way in which it is presented.

I have both editions. If you can find the old one in a used book store - which looks like a large paperback novel with a red/blue cover - I would prefer it for its technical content and formulae over the newer one.

There are a number of individual books such as Paul Haney's "Inside Racing Technology", Forbes Aird's "Race Car Chassis Design & Construction", Herb Adams' Chassis Engineering", and.....

......here's a GREAT surprise for the Street Rodders and Drag Racers who have had the patience to read this far....... LOL!!!

....two books from your friendly MOPAR dealer's parts department - "Oval Track Modifications" and "Chassis - Speed Secrets". The second book has a LOT of general stuff for street rodders and drag racers. In the $20-$30 USD range depending on any discount your MOPAR dealer might pass along to you.

There is ONE book which I would not recommend, and that is "Stock Car Setup Secrets" by Circle Track Magazine's Bob Bolles.

I've been told that his engineering degree is in Civil Engineering - streets, sewer systems, utility lines, etc., NOT Mechanical Engineering, and I believe it shows in this book, which, unfortunately, I also own.

If you've read his tech articles in the magazine, he describes things, but doesn't explain how the theories work. The book is much the same.

My current favorite magazines are two British publications, with which I am sure Peter R. is quite familiar - "Race Car Engineering" (monthly) and "Race Tech" (every other month). While they are targeted towards Formula One and World Cup stuff, there is often enough technical information on new concepts to make the purchase worthwhile, IMHO. ($8.95 USD).

I think as you develop basic knowledge, you start to thirst for more, and the order in which I have presented the above publications, pretty much outlines the road I followed to where I am today.

There is a ton of information out there. I'm sure I am overlooking a lot of it.

Sometimes you have to buy a book just to get a single bit, but it is often that particular bit that allows you to prepare a slightly better car than your competitor - or to better understand exactly what your car is doing and why it is doing it!!

The cross-application and cross-use of the information and knowledge is amazing.

RCE - a F-1 publication - recently ran an article on how Top Fuel drag teams work on a car's launch. Wanna' bet an F-1 engineer or two gleaned a morsel for his team out of that article???

Sorry about being long-winded, but I HAVE done a bit of research in the racing information area, and wanted to pass it along in case any of you might want to upgrade your knowledge of motorsports engineering.

B.P.

[sport.]

My buddy has the street stock chassis technology book and I was flipping throught it and they sware by the camaro's in that book(LOL)

[Bob Paulin]

My buddy has the street stock chassis technology book and I was flipping throught it and they sware by the camaro's in that book(LOL)

Yeah, but much of the technology that applied to the old four-coil-spring Chevelles in some of the earlier Steve Smith books STILL applies to the four-coil Metric car.

B.P.