drivinhard

Thought I would post this. Sometimes I'm a small detail junkie.

IIRC, GM claimed the switch from 01 to 02-04 wheels was about a 1.6 lb weight savings total. I think they were claiming something like .3-.5 lb per wheel depending on front/rear.

I posted this a couple of years ago:

I get 20.32 lb (and ever so slighty more) for my other 01 Alcoa 17x9.5. These are cleaned to like new, dried, no wheel weights, center cap, or valve stem. Dead nuts accurate (verified on 3 other scales) digital shipping scale.

So where did the 19.6 lb "spec" weight for the 01 front come from? GM? Pre-painted "as forged" weight?

Also my 02-04 Speedlines w/ F1 SC's come in at roughly 1 lb less than my 01 Alcoa w/ F1 SCs at virtually the same tread depth. My hunch is the 02-04 (based on the 01 combo wheel/tire weight, 01 stand alone weight, and 02-04 combo wheel/tire weight) Speedlines are more than .3 lb lighter (GM spec) than the 01s. But closer to .7 - 1 lb lighter than the Alcoa's (per wheel).

Last week when I was mounting up my four 275/40/17 A6's on my 17x9.5 C5Z wheels I took some weights and confirmed my hunches.

All weights on my certified digital shipping scale.

My last set of 285/35/18 Nitto 555R2's varied by as much as 1/2 lb (!) when new, which I thought was a lot of variance for a DOT R compound tire. My A6's were very consistent, within .1 of a lb

So here's 2 Alcoa wheels and 2 Speedline wheels with A6's on them (I ran these at CMP w/ NASA this past weekend as a square set up).

42.34 lb (speedline)
42.24 lb (speedline)
44.06 lb (alcoa)
44.14 lb (alcoa)

As you see, the Speedlines (as I suspected awhile back when weighing various wheels/tires around here) come in ~1.8 lb lighter PER wheel. If you figure the same for the rear, you are talking 7-8 lbs at all 4 corners, all things being equal. That's a lot.

Also interesting to note, than a 275/40/17 Hoosier is essentially the same weight as a 265/40/17 GY F1 SC (close to the same size) despite being touted as a super light weight tire compared to street tires. (Front 01 Alcoa Forged wheel, 5/32nds used F1 SC - 43.72 lb)

Just some real world numbers...

DarkMastyr

Great, thanks for the heads up! I'm looking to get a set of rear 18x10.5 all around myself for track days. This will give me some info on the market for these wheels.

froggy47

Great post, thanks.

drivinhard

I will do the same next go around with the 18x10.5 and 18" hoosiers

varkwso

Your day job is? Sounds like an Engineer or Scientist or warehosue shipping clerk (having worked as all three I can see linkage - one even paid well).


Having tossed many of the tires/wheels in the back of the truck I am amazed at the difference in tire/wheel weights also.

AU N EGL

and your cars acceleration difference between a 40 lbs wheel /tire comb vs a 50 lbs wheel / tire combo and forbid a 60 lb wheel / tire combo

what is it, ~ 1 lb removed from rotational wt ( unsprong ) is approx to removing 6.5 lbs of sprong wt out of the car

Jason

Now that's scientific.

I definitely felt it Tuesday morning.

SHOCheapRacing

Brand new Hoosier R6 295/30-18 on Speedline 46.48
#2 R6 45.78
Used Michelin Porsche Cup 27/68-18 on Speedline 43.82

Michelin is at about 60%ish, I got them used

I will weigh all 4 Hoosier R6 when I install/bleed brakes this weekend.

Am I in trouble against 18 GT3s next week at Watkins

vms4evr

I only have an analog bathroom scale. My wife swears it is not accurate Unfortunately it really is pretty accurate.

I've got some relatively new Hoosier A6s. Fronts are 315/30-18 on Speedlines. Rears are 335/30-18 on CCW Classic 2 piece. I'll weigh them tomorrow.

The unscientific answer is I would rather pick up the Speedlines than the CCWs. You can feel the difference easily. I've never picked up a lighter 18" wheel than the Speedline.

Graham

froggy47

I agree,

If I were wtw I'd want the xtra strenght, but autox & track day speedline is a fine rim. I am looking for my 4th set.

froggy47

One or two might know how to drive.

drivinhard

I'm not sure I've actually ever seen posted accurate weight from a nice scale for a CCW classic, anybody have a spare 17x10/17x11 or 18x10/11?

The Speedlines are crazy light. I'm always amazed at how many folks (mostly street guys) dump them for a $3k set of aftermarket wheels that weight more.

Also the 17x11 GM GS wheels aren't far behind the 18x10.5"

here's another interested tid bit from the past on the paint on the wheels:

Quote:
Originally Posted by drivinhard
There was a guy on the Z06forum who stripped the paint off a set of 01 forged, and IIRC, it was ~ 1.1 lb per wheel. I'd pull the thread up but their server took a dump a week or so ago and lost the last 6 months of postings.
<responded>
It was I.

I went out and weighed them again. The painted/clearcoat no center cap 18" x 10.5" OEM's are 22lb each.. and on the same scale the stripped OEM 18" x 10.5"s weigh in at 20.5lbs.

Who knew they still used lead paint... on wheels..

vms4evr

Ok so using my scale.

Speedline, Z06 rear, 18x10.5. With Hoosier A6, 315/30-18. They were used once and have some clag on them, but not bad. 45lbs.

CCW, 2-peice Classis, polished center. 18x12. With Hoosier A6, 335/30-18. Same as above. Used once, some clag. 50lbs.

According to Tire Rack. The A6 is 27lbs in both 315 and 335. So that would make the Speedline 18lbs and the CCW 23lbs.

Found an old CCW Classic, 3-peice, anodized center. 18x10. 20lbs.

The original CCW Classics seem lighter than the newer style. Never weighed them but after humping them around I noticed the difference.

I agree with you Mark. For doing AX or DE the Speedlines are the perfect balance of weight, durability, and cost. Especially considering people unload them on here pretty cheap. I thought of sending a pair of rears out to be widened to 18x12. They would probably come out close in weight to the CCWs but not as structurally sound. So it doesn't seem worth the cost/effort.

AU N EGL

CCW Classics are for 18x12" ~ 21 lbs
CCW Classic tracks are for 18x12" ~20 lbs

the new Classic LM for 18x12" ~ 21.5 lbs

the Classic LM is for BBKs

CCW C14s, or C140s 18x12" ~ 26 lbs

drivinhard

just an update on this, my bare 18x10.5 rear speedlines are 20.7 lb.

43.0 lb with a 275/35/18 sticker A6 Hoosier on them

The 295/30/18 Hoosier's are 1 lb more...

rustyguns

nice! got to love stock rims!

sperkins

Sounds like Santa came early for somebody.

BTW - I just thought about something. My old as dirt 315 R6's are costing me 23 points!

drivinhard

275 A's should be a 14 pt tire for you right, next year?

sperkins

Yeah but I doubt I'll run the A6 unless I can bag a couple of free ones at Rd ATL (which is gonna be tough if Barry shows up). I'll probably go with the Hankook if they ever come off of national backorder ($100 savings per set over the Ho's). You may want to look into that too since the 3 extra points for the A6 is a killer in TTA for a C5Z.

Jeez....why did I just say that?

drivinhard

The 16 pt config I ran the car in this past year, simply becomes a 19 pt config, I doubt I will change tire stuff much, unless there's a totally different tire contingency, with similar performance to the A6.

so are you running TTB or TTA in Dec? I saw TTA on the sign up sheet. I can't keep up with your flip flopping