Sbeckman7's Project: BR1

sbeckman7 · Post by **sbeckman7** » May 24, 2011 10:14 PM

Welded some more reinforcement in the suspension supports so they wouldn't budge when I cut the frame. Didn't have time to tack it today, definitely tomorrow though. I felt like today was pretty productive as it was. First day of work was sweet. Money on the way. Also confirmed that I will be able to use my G265 instead of having to buy a Tremec box, so good news there.

sbeckman7 · Post by **sbeckman7** » May 25, 2011 6:46 PM

So I was about to weld the frame up, and then I realized there was no gas

Instead I started revising the CAD drawing to include the added length. Not as productive of a day as I had hoped.

sbeckman7 · Post by **sbeckman7** » May 26, 2011 6:19 PM

So i have successfully added 4" to the wheelbase, bringing the total to a whopping 107". It's long, there's no other way to say it. If people don't fit now, they won't fit in any car. The extra length will also give me more room to move the engine back, which was a minor concern of mine. I'll just have more room all around. It's heavily tacked for now until Daniel can TIG it for me.

all the way back:

forward for me (5'8")

awww yeeeeaaa

Edit: I've been thinking about how the added length will affect the design of my car, and I think a 107" wheelbase is a bit too stretched for my roadster look. I would make it a coupe but that brings a new set of issues: doors, windshields, more bodywork, etc., so i may end up removing some - or all - of what I have just done. Not sure yet.

Nawwww, it'll be fine

Spence

sbeckman7 · Post by **sbeckman7** » May 29, 2011 2:08 PM

Can't say much in terms of progress except that I have decided to get new wheels/tires as 16" rims will not look good on a car nearly as long as an aston martin DB9. I have decided to go with 19" TSW Nurburgring wheels, which are "forged"

...Running 305/30/19 Bridgestone Potenza RE-11 tires all around, which ironically is what was on the BBS rims when I got the car. Total cost will remain roughly the same as having the BBS rims refinished and widened.

BradM · Post by **BradM** » May 29, 2011 2:43 PM

Wont those be REALLY heavy?

sbeckman7 · Post by **sbeckman7** » May 29, 2011 9:50 PM

BradM wrote:Wont those be REALLY heavy?

Heavier than the 16's for sure... they're 22.4lbs each.

Edit: just weighed the front bbs rims with tires at 40lbs. The new wheels and tires will weigh 54lbs each.

sbeckman7 · Post by **sbeckman7** » Jun 01, 2011 10:00 PM

I was able to salvage the donor strut housings (donated by Mark) today for the threaded portion of the tube, so the front suspension is complete except for some spacers that will hold the Koni's in place. Getting ready to take it home either Friday or Monday

E.rouzbeh.28 · Post by **E.rouzbeh.28** » Jun 01, 2011 11:38 PM

Why the TSW's?

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 12:34 AM

They were the lightest and widest 19" wheel in the price range I was looking for. The Avant Garde M130's have a similar style but with more concavity in the centers (which appeals to me), but they are only 9.5" wide. If I decide to get serious with the performance, there is a rim called the LTW5 sold by Turner Motorsports in 18x10 that only weights 18 lbs. Tires are around the same prices for all sizes.

Post by **mooseheadm5** » Jun 02, 2011 12:39 AM

I disagree with your choice to go with those wheels and tires.

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 12:47 AM

mooseheadm5 wrote:I disagree with your choice to go with those wheels and tires.

I've found tires that are the same dimensions but rated higher and cheaper, but I'm betting the price isn't the cause of your objection. What would you go with and why?

Post by **mooseheadm5** » Jun 02, 2011 12:59 AM

The massive increase in unsprung mass and rotational inertia will adversely affect the suspension, braking, and acceleration. For a performance car this is a bad thing.

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 1:03 AM

mooseheadm5 wrote:The massive increase in unsprung mass and rotational inertia will adversely affect the suspension, braking, and acceleration. For a performance car this is a bad thing.

understood... but I would get the look I want. Wheels are going to be more about looks than performance for now. However, these are the LTW5 rims I was talking about. Same price. http://www.turnermotorsport.com/p-1342- ... eries.aspx

Post by **mooseheadm5** » Jun 02, 2011 1:09 AM

The difference will be readily apparent whether on the street or track regardless of whether you like the style.

The Ltw5 wheels are the wrong offset for you. You would need fat spacers. Just buy good wheels that are the correct fitment.

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 1:16 AM

mooseheadm5 wrote:The difference will be readily apparent whether on the street or track regardless of whether you like the style.

The Ltw5 wheels are the wrong offset for you. You would need fat spacers. Just buy good wheels that are the correct fitment.

I guess I'd be looking at 20mm spacers huh.. I'll do some more looking but nothing caught my eye that is "direct" e28 aftermarket.

Edit: Perhaps I spoke too soon, although it's not the right bolt pattern. Maybe I can find one that is.

http://cgi.ebay.com/ebaymotors/19-Nissa ... 5458wt_941

Post by **mooseheadm5** » Jun 02, 2011 10:05 AM

Stop looking at cheap shitty 19" wheels. Go buy the original BBS wheels that those are knockoffs of but get them used so you can afford them. I wouldn't go larger than 18" and not even that big if the wheel is not lightweight. The suspension you are using is just not designed to handle that extra unsprung rotating mass.

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 8:14 PM

I've been looking more. How bout these? This is the nicest, lightest, and widest rim I could find that was "within" my desired price range. I'm definitely going with 12" rears. Does 10" fronts sound reasonable? Comments, criticisms, criticisms.

http://www.modbargains.com/Forgestar-F1 ... -18x11.htm

Anyone know why the hoosiers are several hundred dollars cheaper than the nearest road tire for a 335 width?

http://www.tirerack.com/tires/TireSearc ... unFlat=All

Post by **mooseheadm5** » Jun 02, 2011 8:23 PM

Will steer like a truck and tramlining will be problematic. You will have a little car that is lightweight and plenty of power, but not retardedly large amounts. You really don't need more than a 17 or 18x9 at the rear and 8 to 9 at the front.

sbeckman7 · Post by **sbeckman7** » Jun 02, 2011 8:33 PM

Alright, I'll go with 9J for the fronts

Tammer in Philly · Post by **Tammer in Philly** » Jun 02, 2011 11:54 PM

This is still wider than you need, but much lighter than the junk you were looking at: http://www.apexraceparts.com/ARC-8-18x9 ... p_133.html

Design-wise, they're a pretty direct copy of the BBS RC. You have essentially an E28 with less weight. You don't need too much tire, and really wide tires will just increase drag (aero drag primarily).

The Apex ARC-8s come in 17x8.5, so you could maybe see if they have that one in a low-offset fitment as well.

-tammer

sbeckman7 · Post by **sbeckman7** » Jun 03, 2011 12:42 AM

Thanks for the link Tammer, those look awesome too

...So do you guys still think I'd spin the rear tires through third gear with 335's?

Post by **mooseheadm5** » Jun 03, 2011 2:06 AM

Why are you convinced that you need such wide tires? Contact patch area is dictated mostly by car weight and inflation pressure as well as sidewall stiffness. Wide, low profile tires on tall wheels on a light car are actually more likely to break traction in a straight line than a comparable height tire with a higher profile, narrower section on a shorter wheel. You will have excess lateral grip even on 225/50-17s. Going much wider can begin to reduce grip in many situations and will make your little car handle like a truck.

sbeckman7 · Post by **sbeckman7** » Jun 03, 2011 2:27 AM

mooseheadm5 wrote:Why are you convinced that you need such wide tires? Contact patch area is dictated mostly by car weight and inflation pressure as well as sidewall stiffness. Wide, low profile tires on tall wheels on a light car are actually more likely to break traction in a straight line than a comparable height tire with a higher profile, narrower section on a shorter wheel. You will have excess lateral grip even on 225/50-17s. Going much wider can begin to reduce grip in many situations and will make your little car handle like a truck.

Part of it is for aesthetics. I want the car to be extremely impacting and over the top in a sense. That, and I honestly thought that the point where the tire width starts having a negative effect on the handling was wayy out there, like 425 width or something. Caterham setup is 195's in the front, 205's in the rear, and weighs a little under 1300 lbs. Ariel atom is 205's front, 245's rear, and weighs 1300 lbs. This probably doesn't work in a matter as straightforward as ratio's, but if I were to use the same ratio's as the other cars with an 1800lb weight (fully loaded), then I would use 265 front/ 285 rear (for the caterham) or 285 front/ 335 rear (atom). That's actually not how I thought it would turn out, so I guess I didn't prove much...

From your personal opinion, what would you say is the MAXIMUM width tire I could run before it becomes detrimental to the car's handling?

firefirefire90 · Post by **firefirefire90** » Jun 03, 2011 4:23 AM

dude honestly at this point, tires are the least of your worries. You need to focus on other things on this build needing attention. You can always dial in the tires at a later date, but from the looks of it your frame hasn't really done as much progression when compared to your drawings. keep up the work, just wheels/tires/seats, are all things that come much later in the build

sbeckman7 · Post by **sbeckman7** » Jun 03, 2011 12:03 PM

firefirefire90 wrote:dude honestly at this point, tires are the least of your worries. You need to focus on other things on this build needing attention. You can always dial in the tires at a later date, but from the looks of it your frame hasn't really done as much progression when compared to your drawings. keep up the work, just wheels/tires/seats, are all things that come much later in the build

I know I know. I'm not buying this stuff yet, I just like to have things planned out. I can't work on the car right now cause of the weird finals schedule and the fact that it's waiting to be loaded onto a trailer so I can take it home.

Post by **tsmall07** » Jun 03, 2011 12:28 PM

You have a decision to make. Do you want to be a poseur that wants to make his car look as good as possible, or do you want to be a respected builder/driver that wants to make his car perform as well as possible. You can't always have both. I know which one the guys around here would prefer.

sbeckman7 · Post by **sbeckman7** » Jun 03, 2011 2:15 PM

tsmall07 wrote:You have a decision to make. Do you want to be a poseur that wants to make his car look as good as possible, or do you want to be a respected builder/driver that wants to make his car perform as well as possible. You can't always have both. I know which one the guys around here would prefer.

Tammer, here's an idea - because I do want both

The BBS's are the perfect diameter, width, and weight for some track compound tires. I'll get some hoosiers for those and stick the uselessly fat rubber on the street tires. Win win, and I get to keep the rims.

Xenocide · Post by **Xenocide** » Jun 03, 2011 2:21 PM

I personally don't see a point in putting fat ass tires on there for the street. They're really expensive and don't add anything. If you have an open wheeled purpose built track car on the street you'll look like a badass no matter what rubber you've got on it. You could roll on 185/55/R13s and you'd have my respect.

PS:
I've been following this since about page 3 and I'm very impressed by your ambition, work ethic, and knowledge. I absolutely cannot wait to see this thing drive.

sbeckman7 · Post by **sbeckman7** » Jun 04, 2011 4:26 PM

Xenocide wrote:I personally don't see a point in putting fat ass tires on there for the street. They're really expensive and don't add anything. If you have an open wheeled purpose built track car on the street you'll look like a badass no matter what rubber you've got on it. You could roll on 185/55/R13s and you'd have my respect.

PS:
I've been following this since about page 3 and I'm very impressed by your ambition, work ethic, and knowledge. I absolutely cannot wait to see this thing drive.

Thanks man! I appreciate it. I've been reading about tires for about 2 or 3 hours... Why did such a seemingly simple concept have to be so complex. I'm reviewing my options as of now, will let you guys know what I decide on. I can say now that the front's will not be larger than 245's.

I used the extra time after the minimum school day to start on the rear shock mounts at daniel's shop. It didn't go very well due to issues with the mill repeatedly shutting off. Anyway, here's what I started on (I'm actually doing the work this time!

)

sbeckman7 · Post by **sbeckman7** » Jun 06, 2011 4:15 PM

Car is home

MyE28.com

MyE28.com

Sbeckman7's Project: BR1