New car build

[mjalaly]

Hey All,

I wanted to get some feed back on a car design (this is under way)

Here are the details roughly...

Chassis: 4130 (may switch to Dom 1020 if someone can give me a good reason that isnt cost related) and is about 95% complete from a design stage.

Suspension: Uprights, etc are custom designed 7075 with carbon A Arms.

Engine(s): A B20Vtec and a B16 turbo (light pressure for quick spool). The B20 has a full race port and polish (vague i know) with all titanuim uppers and dual valve springs good to 9500 rpm with the current set up. The block is slighly oversized with shot peened rods and 11:5 compression pistons. Probably good for 250whp (high altitude... 130whp)

Has anyone figured out a way to convert the Honda B Series rod shift linkage to cable so that i dont have to run extended rods under the car??

Here are pics. Which do you guys like? I think i am leaning towards #2. I have also attached a pic of the carbon test piece to test the epoxy bond

Open for name suggestions too!

Thanks guys!

[mjalaly]

Should this be moved to General Discussions?

[Karlo]

I think you are in the right place.

[mjalaly]

More pics

[mjalaly]

Updated chassis pics

[VR4 Shaun]

How long do you plan on having this car and under what conditions do you plan to drive it(street/track)?

Chromoly does not have the flex that the 1020 has. Everything that I have read points to 1020 being the choice metal for road-going cars.

[mjalaly]

I switched to DOM 1020 for all of the tubes

[FIAROADSTER]

Couple of thoughts on the chassis.
What is the thought behind the arced lower rail and then attaching a "basket" in its stead?
Don't know about the forward leaning roll bars.
Engine install looks difficult.
What are your plans going forward?
Kudos for your efforts so far. Hope to see more

[cordycord]

I switched to DOM 1020 for all of the tubes

Chromoly is the same weight as DOM. In order to take "advantage" of chromoly you need to go to a thinner wall, and then heat treat. Otherwise, you've got suspect welds.

DOM is easier to find, less expensive, and easier to fix when you bin your car. :)

[mjalaly]

Couple of thoughts on the chassis.
What is the thought behind the arced lower rail and then attaching a "basket" in its stead?
Don't know about the forward leaning roll bars.
Engine install looks difficult.
What are your plans going forward?
Kudos for your efforts so far. Hope to see more

The mid curved tube will provide impact resistance from those bad car drivers on the streets. Was that what you were asking?

Leaned roll bar is just for looks as of now. I don’t see them being any weaker than fully upright since there is a trailing connection to the rear suspension box. On the same note the roll bar extensions will be removable so that engine install and removal will be simple

Plans, i bought some Ø2.0 x 16ga so that i can get a feel for the notching and welding. I am going to start that this weekend. Since i changed the suspension arms for now to DOM 1020 as well since you cannot have a legal car and carbon tubing without sing off for a PE, you also have to have a windscreen and wiper (which can be a clip on) and no i asked if i could just wear a helmet but that right is only for motorcycles, which in Colorado you don’t have to wear anyway.. but my car needs a windscreen :huh:.

Started turning the bearing housings from rod stock. I realized it would be easier to turn down the parts from Ø1.5 x .250 DOM, then i won’t have to drill a hole clean through. Taken before i added the large lead in chamfer.

Thanks for the input :thumb2:

[mjalaly]

Chromoly is the same weight as DOM. In order to take "advantage" of chromoly you need to go to a thinner wall, and then heat treat. Otherwise, you've got suspect welds.

DOM is easier to find, less expensive, and easier to fix when you bin your car. :)

I was actually going with 4130 because it was cheaper! I was able to it get for half the cost of DOM locally, however, yesterday i found a place suggested by the 4x4 guys called Hinton here in Denver that is way cheaper for DOM. Best thing.... 6 blocks from my office! :run:

[golftdibrad]

for a road car I HIGHLY recommend you go with steel for the a-arms. Also, your Al rod ends look time consuming and may be just as heavy as off the shelf steel versions. I would also make the uprights from steel as well, or use an OEM design.

[mjalaly]

sorry i havent updated ina while. So i purchased the two upper tubes which are double radii. Denis also over at dp cars ordered up a set of Dynapros hat and rotors for the new upright design and hopefully after the rapid parts get done this week i can fit everything together.

So the question for everyone.... lower steel structure with an aluminum floor or should i get my hands dirty and build a tub? Pros? Cons? Open for suggestions. The lower steel structure is 40lbs according to solidworks and i am thinking a tub would probably be about the same. I will model something up and compare.

Also my good friend came over yesterday and i showed him my awesome looking welds on my control arms and he said... they look good, not enough penetration. I think it might be wise for some one to weld those solid. ; (

[mjalaly]

Updated suspension pics. I decided to use a Nordlock with a nut on the bottom, from some suggestions, instead of a bolt thread into the bottom of the upright.

[mjalaly]

HA. The brake caliper model i had was off by .050. The RP build highlighted this and i was able to correct it before machining parts. (note these were made prior to the upright changes)

[mjalaly]

I received the two top double radii main tubes from the bender. They look great and are really flat. I also updated the look of the car. Open for suggestions on the front.

[mjalaly]

After fighting the CNC program, we were able to get a set up part run (first two pics) and start the other four parts

[Karlo]

So the question for everyone.... lower steel structure with an aluminum floor or should i get my hands dirty and build a tub? Pros? Cons? Open for suggestions. The lower steel structure is 40lbs according to solidworks and i am thinking a tub would probably be about the same. I will model something up and compare.
(

I vote for the lower structure being steel, I see the pics of the Ariel Atom aftermath see links below and cannot help to think that steel would be better than carbon or fiberglass.

http://exocars.net/showthread.php?t=657&highlight=crash

http://exocars.net/showthread.php?t=354&highlight=crash

[mjalaly]

I vote for the lower structure being steel, I see the pics of the Ariel Atom aftermath see links below and cannot help to think that steel would be better than carbon or fiberglass.

http://exocars.net/showthread.php?t=657&highlight=crash

http://exocars.net/showthread.php?t=354&highlight=crash

The Atom uses ERW tubing VS the DOM (which is slightly stronger) I am using and I think my walls might be slightly thicker at .065

Yeah I am not sure how to significantly reduce that issue though. Yes putting more tubes in the bottom might make it safer but i cannot be sure though without the FEA and it isn't working with the curved tubes.

The only good confident way to keep the car very safe is to make a large backbone between the driver and passenger. Maybe just running large tubes from the front suspension box to the rear?

I am really open for suggestions here. I attached a pic of the bottom structure with bars. Also i would think that the carbon would have better crush resistance than just steel on the bottom since it ties more of the structure together.